. In R .

\ V, o. "flu -

. n 3.... . ....... ~ : Wu”

H n- .L . w» “cl“

”n“ M ”.o c» r. 4‘ c V .0 V‘.¢“‘O
. .. . . . .

a w m. ‘. cc ..... . .. 1 .
r \ ... x. .. a. .... a4 _ .....
. ._ . q. A ... . s . ...u.- ... ..
.... . r. . m”.-. . .1 Rd 0.. v; he
ate as.“ ... ... aw mm . a ma...
H. .J v z r...“ . i . .. cm...»
..x 2.... . m r... u. . $5. ... .-
. L . t .... . . .. ‘ w . rm.“
3 . a .3 u a i. i .a
. . . m . a.“ .. ...u n ... 2w... «5..
u . r. n. 1.. a3 . ...Ac ’11 O
“..4. .. .s . In” "x; a. H «\U r. A . r
L . a . .

’-
I
Q
:\
s:-
4‘
u:
.
8.
z'
'
D
d‘
’2
'¢

1 . a Q. ”53‘
. o o I . ...
.n. . .4. — . u. . I‘d 0.1M. _ .‘
.M . . .u it 49... m .
mm 3 .. .. M. A
m _ ”wan . ... .... . 1...;
\I . Q.“.. 4‘ Q. I
a . d O . - ‘IJ .- r .
Q . .. . . . . .
. u. L a: a .
Q. .1“ mojud n31
. . . - L
PA...” .- .. Ir.“

5 g 2 :5.

 

1m

 

  
 

LIBRARY

Michigan State
University

 

 

 

AN INVESTIGAIION OF CHEEICAL METHODS FOR THE SYRTHESIS CF
tlphI-AKINO-hotl*BUTEEOIO ACID (VINYLGUICINE)

3y
LEOPHAS roan

A Thonia

Submitted in partinl fulfillment of the
requirementl for the degree of

RHSTER OF SCIENCE
Department of Chemistry

Michigan 8tgto Univorlity
lust Lansing, Michigan.

1956

t...‘t...fi‘.l.$$$$tt‘tltttt.ttfittfififififiltfit.fifi‘t.t$.btfi¢$.!¥$..#QQC0.0QOQ¥Q.

ACKNOWLEDGMENT
The author would like to express his sincere appreciation to Doctor
James L. Peirley for suggesting this problem and for his guidance and
assistnnce during the entire course of this investigation and during the

preparation of this document.

Qttfifit.tfittfitfifihfiIt’tttfiit......‘fi......‘OQ!...OO$QQO'.O.DO$QtfitO0.0...’O.‘

m DWESTIGA'IION cr Gasman. METHODS ma 1:53 sum-5513 or
alpha-utmo-bem-Bu'rmcxc ACID (vnrzmucnm)

IIDPHIS FORD

AN ABSTRACT

Submitted in partial fulfillment of the
requirements.fmr<UMIdkmwee of

fiMSTER.OP’SOIENCE

thwartnentemftnumdstry
1956

Approved W

 

iBSTRACT

ihe interconversione between hococerine, tErooninc. and el3.e-
aminobutyrlc acid have been demonstrated. The mechnni m involved in
the convrrni on or horoecrine to irrecm no has not been establm had
experimentally. Eavever, it has bccn postulated that Eozoavrine under-

509' do?"drati n to a13ha-nmino-bctn~butenoic acid (vin'lplycinc} and

bccctee rehydrated to give rice to i reonins. Thu», sevrrnl attanpts
have been made to carry cut a cEeaical eynthclls of vinylgl3cine far
he purpces 3f testing iii: an: other ififorice.

hen: unnuccsccful attempts were gale to :rc;nr3 alpha-crino-heta.
gannn-dibr-:cbut3ric sc id (1) ard a133e~arine-vinylnccianiirile (II)-
It was 3ro*oac3 to 0513‘; n 71 rvl- ;.ycinc t‘rougl the dcbro:i.nt‘ on of (I)
or by t‘e Eyirclysie cf (II). Futher attetrte «Ere :nflc to cyntEeaiae
vin3- 15 q'cine tEroz:f‘ tE e melanin ester synthesis. fhin involved the

3re3ernticn of 3Etf.elinide diet‘ylmnloncte and reacting vi 2-bramo-l~
absncl. 1, ?-¢ brancetfinnc. and ecetelfehyde uning 33ridine no a catalyst»
“he chycrati-vn c;f t‘.e errivcry alcohol resulting frtu t c ccnflensation

failed {of -ve g‘t.a1i:.iée vir;‘. r.eloni c ertcr. The deiydrchclogenatian

';tEal 31 ‘chc ie-brwrnc‘” 1‘-¢-M E31-

cf the resulting oil, alleged
nelorste, with 63 :bccquent hydro lysin and cccnrbOHJlat..n. rrve a 6; fit

for on unlnewn a-ino acid when subjectm cto geper c?r$1t3 {rafh . The
dc.yd ru 10 n cf the andencntiG product. alleged 31t'91131sc(3133.a-?3 irony-
ethyl)-Cietk;lnalcnete. obtained by reect'ng :cc1(-lde‘3‘e or: p! :thslimide

diet‘yl: elonnte failed to give a vinyl group. Unsuccessful results

were also obtained when 130 3E1hnllml£e diethglunlcnatc was re,laced

by forrylawinn-dictfiylzalcnatc and subjected to the care t33c reactions

glvcn above. lotassium 3EtEclinide dicthylnnlonctc failed to react

with clea-chloro-vinylncetonltrllc 1n tie mortal way.

The author was barn January 1?. 1379. The bacEclcr of aciencc degree
was conferred to E1; in June, 195% a% a. and T. College, Greensboro, 3.0.
23 we: a upecial research assistant. on a ngcrnaent cycncércd project.
from lth-lifioo filth pert-time reocarch. ha taught {ancrcl chemlctry from
19§C~l$51 at a. and To College.

fie carved in the cililcry service for two years ans was employed
by the government one year as a cEczint. 3E0 cbcvc 3caltlon an n ohcmlnt
vac reel“. d for tEe purpose at engaging in grecuntc etudy in tho field

of cEcnlctry. Thus, he catered EicElgan State the ayrlng quarter of I?" c

 

 

2503
I. IKTRCZCCEICR L h k -w 1
11. KISTtRICAL — ~—~~A w A - : 2
A. LL’MBLLIS L G? as. 1: 0 mos - . r 2

 

3. CHLFICAL'

1. Th» preparaticn and prapertieo of substances
related to alpha-aminc-betc-butenoic acid —---- 10

2. Proposed pathways for the oynthesia of alpha-

 

 

amino-botn-butanoio acid ~ “- ~ “‘ A 15
III. EXILLIILKTAL A f , _ A “ A “:“2 L w“ *— + A ~: 50
‘0 A; LEI“ 5Y3“ fiiSISI

1. Reaction of dlbromoactolein. ammonium chloride,
and sodium cyanide — :* * w * 50

 

2. Reaction of acrolein, ammonium chlmride. and
sodium cyanide “‘~v—~ w “ ‘w ‘ “‘ 56

 

 

5. Preparation of vinylglycollc nitrile “ - ~ .— ~_;; fifl
4. ireparation of alpha-chloro-vinylacetonitrilo .-~ 33

5. Rea.ct1an of a1pha-chloro-vinylacetonitrile with
potasei 2m phthalirM’a ““A “ ~ * * ~ 39

 

3. EALCNIC ESTER SYETNESISI

 

1. {reparation of forzylaminomelonio erter “- ~ 40
2. Preparation of aodio-fortylaminoxalnnic eater -- 43

3. Reactien of: noeio-farzylaminoaalonic enter with
ethylencbrozohydrin ~f "w _- AL TA he

 

h. fi.oaction of formylaninomalonic enter with tests!-
dehyde WA : ~* ~— 7 * :~ w~‘ ~ «w “5

 

 

5. ire; aretion O! et‘ “’1 honobrorzomelenate - ~—~: M

PACE

 

(3. Preparation of potassium phthal i: 133 — — ‘ ~= 3+5
7. {reparatian of phthalimirfie diet'zylralmmte ...—...... ‘35
o. Ercgaraiion of aodio-phthal‘giin €1et£*_knlonnte- #6

9. Reaction of codio-phthalizidc diot‘v1.alonnto with
1,2—dibromoethane w w __v 46

 

10. thsdrohalorenetion reaction uaing potaaeiam
a iie in liquid ar:.onia w: 49

 

11. -.enction of ao‘ifi—rht‘alitifia diethylmaionate

 

 

 

 

with 2—bramo-1-ethanol w v . ~ 51

12. Reactian of acetaldehyde with phthali:ide
diothylzalonatc : w *‘ .2
IV; LIS"CL~,ifR A: RESULTS _ __ A _ A“** y}
7. SEQ-"SALE? -~* A - — — :~ ~ :: 59.

BIBch.rzf-z.u‘-IEY-— 7 ~ * ~ * M ~ - 61

 

(1)

INTRODUCTION

luring the pact decade ccientific investigator. have recorded many
new obeervatione, learned new facts. and propoeed new theoriee concerning.
the pathwaye of biOgeneeie of the organic constituente of biological eyetene.
Of theee varioue ccnetituenta, the important group of alpha-amino acide hae
received considerable attention. Nevertheleee, many uncertaintiee remain
ac to the preciee nature of the reactione involved in the eyntheeie and
transformations of come of theae compounde. Ancung these uncertaintiee
is the nature of the mechanicnc which bring about the interconvereionc
pceeible amoung threonine, homo-crine and aminobutyric acidt One pceeibil-
ity here ie that each of theee compound. may be converted to a common
intermediate, alphe-amino-beta-butenoic acid (vinylglycine). which then.lay
give rice to each of the other compounde by the addition of water or hydrogen.
A direct teet of thin poeeibility hee not yet been poeeible. for the
postulated intermediate. vinylglycine, hae never been prepared and ite
properties are accordingly unknown. in inveetigaticn or varioue nethcde

for the chemical eyntheeic of thin compound has therefore been undertaken.

(2)

HISTORICAL
A. Amino Acid ketabclisns
Experimental results obtained by Horowitz. Tees, and Fling (l. 2).

using nethionineless and threonineless mutants of Neurospora crassa, gave
specific evidence for the following relationship between the bicsynthesis

of threonine and methionine.

..LC) Homoserins -$§2--§>~ Threcnine
f
um...) emu” 4&2“; ”ammo. ...—....)

Honcsystcine ---->- Rethionine
Buss (5) has shown that there are at least three genetically different

mutants in the group blocked at Stage-A.vhich grow when supplied with cysta~
thionins but not when.supplied with cysteine. Fling and Horowitz (4) used
these mutants to carry out experiments to obtain a futher insight on the
conversion of cysteine to cystathionine. The results of a cross-feeding
experiment showed that the Extracts of any of the three mutants supported

the growth of a threcninslees mutant. No. 55fi25 (blocked at Stage B), and

of a homoserineless mutant, No. 5150A (blocked at Stage 0). The active
fractions from extracts of methionineless mutant 9666*will support the growth
lot homoserinsless mutant 51504 in the absence of threonine (only L-honcserine
will support normal growth of strain filfioh in the absence of threonine).
Chromatographic and biological results provided strong evidence for the

presence of thomoserine in extracts of methionineless mutant 9666 and of a

(5)

double mutant 9666-55h23. Since extracts of a methionineless mutant of
Reurcspcra ggsgga contained two substances, one active for threonineless
mutant 35425 and one for homoserineless mutant 515Gb, one may regard this
as being very strong evidence to support the theory that methionine can
be converted to L-homoserine and threonine under the experimental conditions
used with these specific strains of Neurospora gggggn. Strain 51504 was
employed by Horowitz et al (2) in conducting the following study. Strain
5l504 was orginally classified as a threonineless mutant, since threonine
was the only amino acid tested upon‘which it showed any growth. Of twenty-
five amino acids tested in concentrations of one mg. per 20 cc. of medium.
only DL-threonine supported growth. Futher study of the growth requirements
of strain 5150# showed some factor or factors present in casein hydrolysate
stimulated growth in the presence of small amounts of threonine. although
no response was obtained with casein hydrolysate alone.

flethionine was the only aeino acid tested.wlich stimulated growth in
the presence of threonine. Attempts to replace the threonine portion of
the requirement were carried out by supplying each of twenty-five amino
acids in the presence of methionine. none of which replaced threonine.
ruther tests were made to determine whether known precursors of methionine
are able to fulfill the methionine requirements of the mutant, and the
results showed that cystathionine and homocysteine (as the thiolactons).
but not cysteine, will support growth of strain 51504»when supplied together
with threonine. Thus, the authors reasoned that the cleavage of cystathionine

to yield homocysteine and the methylation of homoeysteine proceeds normally

(k)

in the mutant, but that the synthesis of cystathionine from cysteine is
blocked. This suggested that cystathionine and threonine have a common
precursor whose synthesis is blocked in the mutant. To futher substantiate
this theory the authors searched for a substance which, when supplied to
the organism, would satisy both the methionine and threonine requirements.
DL-Homoserine was synthesized and found to be active when tested on strain
51504. The activity of DL-homoserine for strain.§l§04 is equal to or better
than that of a mixture of DL-threonine and DL-methionine. a fact which adds
weight to the idea that homoserine is a normal biological precursor of threo-
nine and methionine. Thus, it appears that homoserine acts as a precursor
for both methionine and threonine infl!eurospora.g§22§a. The authors suggested
that the conversion of homoserine to threonine may involve the dehydration.
of homoserine to the beta-gamma-unsaturated amino acid with subsequent re-
hydration to threonine. It was glso suggested that homoserine may act as a
specific amino group. or even hydroxyl. donor to the immediate precursor of
threonine. I

In similar experiments with twelve amino acid-requiring mutant strains
of Bacillus subtilis Teas (5) found that seven required threonine, two re-
lquired threonine and methionine but could use homoserine instead. and three
required threonine and methionine but could not grow on homoserine alone.
The indications are that in Bacillus subtilis. as in.Neurospora.g£=33a.
honcserine is a precursor of both threonine and methionine. Cohen and
Hirsch (6) carried out the conversion of L—homoserine into L-threonine hy

using a suspension of Escherichia coli and threonine synthese. Threonine

(5)

was found to be destroyed by threonine deaminase at a rate preportional to

the threonine concentration. Futher experiments were conducted by Hirsch and
Cohen (7) which gave evidence of L-homoserine as an intermediate in the trans-
formation of L-aspartic acid into L-threonine by Eh 2223, Escherichia ggli,
type ML converted L-homoserine to L-threonine, and also transform L-aspartic
acid to L-threonine. However, mutant ML 52 can not synthesise L-threonine
from L-homoserine, but transforms L-aspartic acid only to L-homoserine. In
the unmutated XL E, ggli_no L-homoserine is detectable since it is converted
very rapidly to L-threonine.

Umbarger (8) carried out quantitative growth experiments with three-
nineless mutants of E} 2212, Strain RES-60 grew rapidly on L-threonine or
DL-homoserine but grew slowly on D-threonine, alpha-ketobutyrate, alpha-
aminobutyrate, or L-isoleucine. Delluva (9) grew E, 2212.1” glucose-phos-

phateeNHAOl medium with either 01‘-labeled oxalacetate, aspartate, or formats.

The distribution of 014 in the threonine and serine indicated that a four-
carbon unit was the source of threonine. Kalan and Ceithaml (10) carried
out experiments which involved the biosynthesis of methionine in E, gait.
Pour groups of methionine-requiring mutants of £3 gall, strain V, were
isolated by the penicillin.method, one of which would grow on alpha-amino-
butyric acid, homoserine, alanine, valine, isoleucine, as well as methionine,
homocysteine, and cystathionine. The results obtained from these experi-
ments are consistent with the hypothesis that a four-carbon unit, amino

acid, is a precursor of methionine in E, coli. Cohen, Hirsch, Niesendanger,

and Rieman.(ll) found that extracts of E, coli converted L-aspartic acid to

(6)

L-threonine. Extracts of’gy ggli_EL 52 possesses a glucose-é-phosphate
dehydrogenase which can couple with the system reducing the aspartate to
homoserine through triphosphopyridine nucleotide (TEN). Extracts of g}
3232.3 184 can not reduce aspartyl phosphate to homoserine. Extracts of

a third mutant are able to couple dehydroEenation of glucose-6-phosphate
with reduction of aspartate, but homoserine is not formed. The sequence for
converting aspartate to homoserine is postulated to be: ”M beta-
aspartyl-phosphate M X ~~~-> khomoserine. with homoserine
as substrate, extracts of E9 ggli'B 18# form small amounts of an alpha-keto
acid in addition to threonine. Extracts of E, ggli_(12) were found to re-
duce aspartic acid to homoserine in the presence of glutanic acid, tri-
phosphopyridine nucleotide, and adenosinetriphoaphate (AEP). Homoserine

was transformed to threonine in the presence of ATP and pyridoxal phosphate.
Black and Wright (15) carried out an experiment which demonstrated an enzy-
matic reduction of beta-aspartyl phosphate to homoserine. Watanabe, Xonishi
and Shimura (14) demonstrated the biosynthesis of threonine from homoserine
in aqueous extracts of acetone-dried baker's yeast.

Several experiments have demonstrated the conversion of threonine to
amincbutyric acid. Culture filtrates of various bacteria grown in casein
hydrolysate medium were examined by paper chromatography by holwod and
Froomn(15) for the appearance of new ninhydrin spots. It was found that
washed suspensions of Staphylococcus £25329 cultures produced alpha-amino—
butyrie acid from threonine possibly by the removal of the hydroxyl group.

Lien and Greenberg (16) carried out both in vitro and in 23!? experiments

(7)

which demonstrated the interconversion of threonine and aminObutyrio acid.
In th‘.2P*I$EEP eXperiments, radioactive threonine was incubated with a
suspension of cytoglasmic macro granules of rat liver in a synthetic medium.
In the i2;zizg experiments, each rat was injected intraperitoneally with one
to ‘6 mg. of CIA-labeled threonine dissolved in 1 cc. of water. The results
from both 12_vit£p and in lilo experiments gave evidence that DL-threonine-
2-01‘ was converted to alpha-aminobutyric acid.

The identification of alpha-amincbutyric acid formed during threonine
incubation was based on a positive reaction with ninhydrin, the coincidence
of the ninhydrin spot of known alpha-aminobutyric acid with the radioactive
materiap from the peaks as determined by radioautOgraphy after two-dimensional
chromatoEraphy on paper, and the very close coincidence of the radioactive
peak and the ninhydrin peak when a portion of the material was rechromato-
graphed with 13 mg. of known alpha-aminobutyric acid on a Dower column.

The tentative identification of the few micrOgrane of alpha—aminobutyric
acid, by Lien and Greenberg was based largely upon chromatographic evidence.
In order to verify the previous identification, a large scale enzymatic
preparation of alpha-aminobutyric acid was performed by Lien and Greenberg
(17) using “ls-labeled DL-threonine. The yield of alpha-aninobutyric adid
was much higher when threonine was incubated with a rat liver homogenate

in KGl-KHCO, buffer than when the incubation was carried out in the cyto-
plasmic macro granule system. The alpha-aminobutyric acid was characterised
by conducting a nicro-Kjeldahl nitrogen determination, an infra-red spectrum,

and a chemical degradation. The fact that the transformation proceeds by

(8)

he way of alpha-ketobutyric acid suggests a deamination step, with sub-

sequent ”Insemination to form alpha-aminobutyric acid as follows:

an, - son as? of .93
s-cs-os—coos ......) CHE-CIFCo-COOH -—-—-.>CH5--ca2 «coon

 

03°
(Threonine) - '
”son ' (transamination 1m,
L—é caresses-coon e w .— CHz-CH err-coon
- ctr-13 " (.1 pha-dminobutyric)
acid

In a study of serine and threonine deaminase activities of wild type
Neurcs ora gragga, the formation of alpha-ketobutyric acid from threonine
has been demonstrated to take place in cell-free extracts of E: 35322: by
Reissig (13). Lenti and Grille (19) found that in quiescent suspensions
cf'gh ggli_there is active deamination of DL-threonine to alpha-ketobutyric
acid.

Heyns and Walter (20) demonstrated, by chemical means, the formation
of alpha-aminobutyric acid from threonine. Threonine hydrochloride heated
a few degrees above the n.p. (lhOeZ) decomposed with gas evolution and
darkening, and after a few minutes alpha-aminobutyric acid was formed.

Only threonine gave this reaction: under similar conditions eerine gave
alanine. Vieland and Birth (21) have conducted similar experiments.
Armstrong and Binkley (22) reasoned that alpha-aminobutyric acid may serve
as a substitute for methionine and threonine, involving a mechanism.as
simple as a1pha-beta-dehydr0genation followed by readdition of water to the

unsaturated amino acid formed.

mag - an Nib HOB w?
635-0112434003 —-—-—) cares c-coca ......) on; 48434003
on

\7I

Diets lacking in methionine and in threonine, but adequate in all other
respects, were administered to young white rats, and the ability of alpha-
aminobutyric acid to substitute for each of these was tested. The results
showed that alpha-auinobutyric acid can neither substitute for threonine
nor provide the four-carbon chain for the synthesis of methionine under
the conditions of the experiment. Armstrong and Binkley (25) conducted
OXpOriments to deterrine whether young white rats were able to carry out
the synthesis of methionine from honoserine, choline, and cystine. as a I
results of the growth experiments it was concluded that DL-homoserine in
the presence of cystine and choline will not substitute for methionine
under the conditions specified. Fronageot and Clauser (24‘ deronstrated
the non-reversibility of the conversion of methionine and threonine to alpha-
aminobutyric acid in the rat.

EXPeriments conducted by Fairley (25) demonstrated that either amino-
butyric acid, homoserine and threonine could support the growth of certain
pyrimidineless strains of.§:crasea. Aminobutyric acid and homoserine were
about equal in ability to promote growth, while threonine was considerably
poorer in this respect. These results indicate that, although the compounds
are interconvertible or convertible to a common intermediate, homoserine is
not converted to aminobutyric acid through threonine, and strengthens the
possibility that vinylglyoine may be the central compound in the inter-

conversion reactions.

.e Obesicels .
Several theoretical patrways for the chemical synthesis cf alpha-seine-

bete-butrnoic acid (vinylglycine) may be proposed. but. I search for the
proper conditions to transform tfiese theoretical yethuays into practice!
epplicetions fey prove to be less fruitful. As has been indicated. s search
of the literature revealed that vinylglycine has not been refortec in any
respect. ihus, in etterpts to synthesize this compound the pretaration end
chenicel behavior of cornounce possessed of molecular structures closely re~
lated to that or vinylglycine shouli be of rrcet significance.

Before one ettctrts to carry out sny tyee of synthesis. which eight
lead to the formation ff e coopeund such as vinyiglycinc, : ny 'ignifioent
factors are considered. for instance: the stability of tLe con ound. is
it most stable as BbCh. es s salt. or sees other derivative; what are the
significant groperties of each intermediate {or c specific s1nthesis; whet
conditione are necessary to sctivats the lest reectinn in the forestion of
the finel yrouuct, and will these conditions be suificiently Greetic to
promote cecotjceition or structural changes in tie zolecule as it is fir ed;
end cost of all, is the compouna stable unner norsul conditions, i.«. roan
tenycreture, if not, to what conditions must said surgeon: be subjected to

ffect stabilization, and what eppvosch aheuli be enrlcyed to unuesk those
ideal con;iiiona without effecting the compound in the process of doing so.
in sbsolute answer for these and ot or questions about a compound which hes
not been eynt‘csized csn not be obtained, but one can take use of e theoreti-
cal cprroec? end whatever correlations can be derived by e“ploving the be-
hsvicr of closely related substances.

Linetosd, Fable. and 3oor~an (26) node a study of 4ctiods for the

preparation Of [geolefinic colds with unbrenchsd cheins. end :rcnuued that the

(11)

result: are applicable to acids substituted by alkyl grout: at the delta-
carbon or beyond. lg-n-Butenoic acid, prepared by the triethenolamine
baee-catalyzed method, was obtained in an optimum yield from malonic acid
and an excess of acetaldehyde. The method of Houben (27) gave vinylecetic
acid from ally]. bromide, and carbon dioxide by the firignard reaction. This
compound yielded a dibrozide corresponding to that prepared by Fichter and
Sonneborn (28). Using essentially the method of Bruylent (29), Linetead,
Noble, and Boornan obtained the beet yields of vinylecetic acid. by starting
with allyl cyanide. It was found that Vinylacetic acid, although easily
isomerized, is not an exceptionally unstable substance when kept at room
temperature in the pure state. Vinylecetic acid gives the reaction of a
carboxyl compound and of an olefin practically independently of each other
because there is no conjugation of the uneaturetion in the two groups. On
boiling with dilute acids or alkaliee, vinylecetic acid changes to crotonic
acid. Gaseous HBr caueee this change even at zero degrees. Concentrated
alkaliee produces two molecules of acetate by shifting the double bond and
splitting the alpha-beta unsaturated cofipound as it is formed. The change
from beta-gamma to alpha-beta unsaturation in a straight chain acid in easy
becauee of the greater lebility of the alpha hydroEen as comeared with the
gamma hydrogen. In one reaction, vinylacetic acid shows a complication
betleen its two reactive groups. It readily changes to butyrolactone
becaueetthe carbcxyl and ethylene linkages can approach each other closely
in epacc (50). This is a very general property of beta-gamma unsaturated

acids, and particularly the four-carbon acids.

\ldl

Remband ()1) made a study of intranolscular transpositions and influences
of acids, esters, and nitrile groups on intrsmolecular transpositions of the
sllyl type. Double decomposition reactions with alpha-substituted‘unsatursted
compounds of the formula RCH=CH~GH¥R' gave 'normal products‘ of the type
RDIFOlleCH-R' and 'abnormal produits' ROB-CflH-R' by intramolecular trnns~
pcsitic: of the sllyl type. Ramband mzde a study of the influence that the
nature of the radicals R and R' has on the crentiation of the reactions
giving rise to two classes of products and in particular the effect of CR.
DOOR, 0008' on reactions in‘which an sllyl transposition is possible. The
isomerization is proposed to take place in the sense RCB=CHHCHBR' ----€>
ROE-Citefi-R' by the migration of a negative group (anionotrogy) or by the
shift of a hydrOgen atom. RCMH-iH-R' ”..., RCHz-Cfiwx-R' (prototrcphy).
A series of reactions were carried out on CH2 CH-OH-R"where R' is as follows:
3' equal on (I), 3' equal coon (II). R' equal cool»):I (III). 3' equal COOEt (H),
R' equal COOPr (V), leaving 8' intact but substituting the alcoholic 'OH‘
group by another negative group (Cl, Br, 100 and N-Etz). The direct acetyl-
stion of I, II, III, and IV with lcONa went normally and gave satisfactory
yields of alpha-acetina which were extremely resistant to isomerization.

The acetylation of trans-gamma-mrdroxycéotonic acid, HO-OEZ-CPFCH-GOOH.

gave the expected gamma-acetin, AcO~CHé-CH:CHbCOOH. The action of AcORu

on game-brominated esters, Br-CHz-CB‘ZCH-COOR. gave gums-acetins by I totally
normal reaction. The alpha-acetins were sapontfied normally to the acid by

the action of dilute alkalies. The more stable garlna-acetins gave. after

heating with KCH for several days, a hydroxy acid with all the characteristics

(15)

of gamma-hydroxyorotonic acid. Saponification of the gamma-bronoesters with

cold AgCH gave game-hydroxy esters. In a chilled solution of K08 and Ba(08)2

the saponification of the gamma-bromo esters gave gamma-bromocrotonio acid.

On boiling, the hydrolysis became complete, he reaction remained normal

and gave gamma-hydroxycrotonic acid. The genus-bromo compounds gave gamma~

amines on treatment with anhydrous dimtthyl amine, (085)2NK, in dry ether.
Chloronation of Cngzcl‘i-CH-CN, CHflH—CH-COOEe, CHECK-CH-COOEt, and

CH2=CH-CH-CCOPr, with 80012 2: the presencSHbf pyridine gavSHexcellent

OH
yields of the expected alpha-chlor-o-derivatives. fiama-Mdroxycrotonic acid

was chloronated normally to the known gamma-chlorocrotonic acid. The abnormal

reactions by anionotropy according to the scheme d! f CH2:CH-CH+R ----;i
I

CHz-CH=CH-R.were studied by the bromonation of the alpha-aIGOhols, the trans-

I
formation of the alpha-bromo-derivatives into acetins and alcohols, and the

action of Ca3r2 and H01 on the alpha-chlcro compounds. The prototropic

abnormal reactions following the scheme 0:1,:cu-cs-a ----) carom-a
' x I

were investigated by the action of NaCH on the alpha-chloro compounds, the
action of NH5, EtREH, and AcONa on the alpha-chloro esters, the action of
strong acids on the alpha-chloro esters and nitriles, the action of bases
on alpha-hydroxy acids and esters, the action of acids on the alpha-hydroxy

compounds, and the action of PBr on the alpha-hydroxy nitriles. The results

. 3
have been compared with those Obtained in analogous studies where the ON,
OOOH. and 0003 functions were replaced by a hydrocarbon residue or by a

hydroEen atom. From a comparison of the tabulated results it is evident

that the presence of a groupk COOH, 000R, or ON, in the alphanposition to

(1")

a negative group susceptible to migration, acts as a stabilizer and hinders
the a1pha,gamma-migration by allyl transposition to a certain extent. It
favors the migration of the hydrOgen atom attached to the same carbon atom.
The gammacsubstituted acids, nitriles, and esters do not seem to give any
abnormal reactions either by anionatropy or by prototropy.

Ramband (52) conducted futher investigations on the preparation and
behavior of alpha-hydroxyvinylacetic acid and some of its derivatives. Large

quanitites of pure vinylglycolic nitrile, CHé:CH-CH~CN and from it the correo
OH '
spending acid and cater have been prepared. These compounds react with $0012

and A020 in the normal way without any isomerization or transposition of
any kind. lhe ganma-bromo-crotonates yields shines, and acetins by normal
reactions. I. passing dry H01 in cold solutions of vinylglycolic nitrile,

CHéZCH-CH-CN, in he-CH, Et-CH, and pr-Cfi, boiling the saturated solutions
under rgglux, penring the reaction mixture into a large volume of cold water
and extracting with Et20, gave the esters CH§=CH-CH-CCCK3, CHé:%HFCH-000Etg
OHé:QH~g§~COOrr. The hydrolysis of vinylglycolicogitrile by diéutSHHCl at

zero degrees gave a yellow sirup which is laborious to extract hith Et20

and difficult to purify either by distillation or by isolation of the zinc-

salt. Treatment of alpha-hydroxypentenonitrile with Ac 0 and AcCKa gave

2

alpha-hydroxyvinylacetio acid, CHéZCH-CH-OOCH, which absorbs bromine. The
DH

drapwise addition of $061 to cold mixtures of the esters of vinylglycolic

2
acid with pyridine gave the alpha-chloro-derivatives. gains-Hydroxycrotonio
acid reacted violently and gave gamma-chlorocrotonic acid, ClCHa-CH=CH-COOH.

The saponificstion of the methyl ester of alpha-chlorovinylacetic acid by

(15)

heating with dilute HCl for three hours gave the acid, CH2 CH—CE-CCCH,
which absorbs bromine. Cl

This docurent is prinarily concerned with the investigation of synthetic
methods appicable to the synthesis of vinylglycine. Thus, with an intimate
evaluation of prOpcrties, methods of preparption, and specific reactions of
closely related substances, a number of pathways have been proposed and
investigated with respect to the above synthesis.

Should acrolein lend itself to the general reactions of aldehydss, with
minimum condensation and polymerization, it would serve as an excellent
starting material for this synthesis. Both the olefinic and aldehyde group.
are sensitive to oxidation. hild oxidation (takes place even in air} give;
glyceric acid, CH2 h-CROH-COOH, and nore vigorous oxidation breaks the chain.
The unsaturated nature of acrolein is shown by its great instability and

tendency to polymerize. However, according to houreu, acrolein can be

preserved for much longer periods by the addition of small quantities of

 

other substances, themselves easily oxidizable (phenols, hydrcquinons, etc.)-
The olefinic group can be protected by bronination.vhile the aldehyde group
is entered into reaction. Thus, it appears that, after the protection of the
sthylenic group by bromination, the Strecker synthesis might be applicable
to the formation of alpha-unino-beta,gamma-dibromocyanohydrin (II), with
subsequent debromonation cf the amino nitrile (II) to give the unsaturated
compound (V), which could readily be hydrolyzed to alpha-amino-beta-butenoio
acid (IV), or the debromonaticn of the dibrcmo amino acid (111) would also

give (1?), However, the debromination of (III) would probably prove to be

(16)

less practical, since the product (IV) has a very good chance cf forming
tho corresponding lactone under the conditions which would be in effect
during the debrouination. The above course of reactions are illustrated by

the follcwlng equations:

 

 

031720214210 / Bra — w>~ BrCHz-CIBr-CHC
(I)
ma?
BrCHZ-CHBr-CHO ,1 Imam / NaCN ”...”; BrCH9-CI-IBr-CH-CN
(II)
3:39 :32
Bronz-crar-cazcu A ) BrCHe-CHBr-CH-COCH
1 ‘(Im

- Bx"2 $~ Bra

$1912 NH

Cflzifl-CH 2-: A ~ A > CH2:CH-CH2-CCOH
(V) (IV)

Attempts were made to prepare (V) directly by a mod1€icntion of tho

 

 

 

original Strecker synthesis employed by Barker and Skinner (55), Zellnaky '
and Standnikoff (5h. 55). Elld hydrolysis of (V) would give (IV). The
.Irooctlons are as follows:

EH

 

worm-cm ,4 mam ,4 Nam-z ......>. CHZEH.CHECN
(V)
“Ha . NH
CHZZCH—CI{=C}I _ A > cg :ca—caz-ccoa
2
(IV)

Ramband (31, 52) and Glottofeld (56) prepared vinylglycollo acid (VI)

from acrololn. Ramhand converted tho alcohol group of (VI) to the chloro-

(17)

derivative (VII) by reacting it with $6012 and pyridine. hany unsuccessful

groups. One

attempts were made to replace the chloro-group also with other
such attempt involved reacting (VII) with KH5 which would normally give the
corresponding alpha-amino derivative, but an abnoreal reaction reaulted.
Hanover, no attenpte were made to react (VII) with potassium phthalimide.

The high temperature necessary for this reaction to go at a reasonable rate
makes it questionable, cc to whether (VII) will undergo polymerization rather
than rcect in the normal way. Should this reaction proceed in the normal way,
it would give rise to an intermediate (VIII) which could readily be hydrolyzed

to giVO (IV).

on
CHEER-CEO } Nam: / AcCH -—---> CHZZCH-CH-Cli
(V!)
on Cl
Cszcfi-CB-CN { cool2 ,1 pyridine -...) CHECH-Ch-CN
(VII)
Cl
Clizl'CE-I—CII-CN / x- 63,4 -.......>. CHECK-CH-I<C>(H4
on c
(VIII)

 

q//CO NH
. p 2
CHEER-Ciro \co>6H4 > CIIQZCH-CH-COOH
CN .
(IV)

Attempts were made by Voorhees (57) to introduce the vinyl group
directly into malonic ester through the reaction of vinyl brouide with the
lodium derivative of phenylmalonic ester. All attempts in this direction
were unsuccessful. Voorhees and Skinner (58) made attempts to prepare
vinyl eneIOgc of barbital (veronel) end phenobarbital (luminal) by the

introduction of the halogen ethyl group into the mono—alkyleted melonic ester,

(13)

with subsequent elimination of halOgen acid directly or indirectly, and
condensation of the resulting compound with urea. They atterpted to prepare
dimethyl phenyl-vinylnalonete through the following ketcne but the reduction

did not proceed in the desired manner.

ottz5--c)Co'J‘c:<:n5 (reduction) > CIIaZCHXCISCPia
06} kcccv ’ orv '~ .5063;

f . ’1;-
/ 5 L w

(Dimethyl phenyl-ecetylmulonete) (Zfinethyl phenyl-vinylmnlonate)

 

I

Diothyl beta-chloroethyl-ethylmalonatc nee obtained in “CflIyield from
the condensation of ethylene chlorc-icdide with ethyl nalonic ester. The
conversion of dinethyl ethylchlorcethylnelonnte to dinetkyl ethyl-vinylmelo-
hate was attempted by refluxing with freehl powered Calcium oxide in xylene
and with sodium.ethylate in ether resulted in the recovery “f the unchanged
ester. floating in sealed tubes in ether solution with sodium ethylate re-
lulted in the breakdown to lower boiling esters. Then the diethyl ethyl-
chloroethylmalcnnte vac heated with dinethyl amine in absolute other in a
sealed tube diethyl beta-diuethylamine-ethylmelonnte was obtained. All of
the above methods foiled to be applicable for the introduction 01“ a vinyl
group in substituted melonic esters.

Cope and Ecfilvnin (59) proposed two seemingly possible cathode of
synthesis of vinylethylnalcnic enter. The first of tfiese invalved the
preparation of the quaternary salt (II) and tLe decomposition of the corre-
sponding base by distillation into the vinylethyloalcnic ester. The pregn-

ration of salt (II) was attempted by reacting trimethylauino with ethyl-

(19)

(beta-bromoethyl)-malonic ester (I). This reaction, when carried out under
conditions which gave a satisfactorfiy rrte of reaction, gave tetramethyl-
ammonium bromide rather than salt (II). She malouic esier Mus isolated as

the hydrochloride of ethyl(beta-dimethyl-amincethyl)-malonic ester (III).

 

(Cfljhfi ,l BrCHQ-CHP-f-(CCOEt)2 > (ca;)z.:-c:z.,-cx~:2-o-(coost)2
’ ‘ it ’ “ n
(I) (11)
3" 0‘1 " *4 "a --'H - oo; -3! ".1: --- ‘I:
c.531- / “3,2. «2 2-360 H)2(CI5),)\ ,4 (”532' -> (c 9143::
(III)

It was found that 93% of (II) precipitated when the reactants were allowed

to stand in other solution for several weeks. But, due to the poor yield

and the time required, the authors abanooned this methoi as being imprectical.
The second and successful method of synthesis of vinylethylmolonic ester 1n~
valved the reaction of 1,2-dibromoethene with sodio-ethyluelonic ester, fol-
lowed by the reduction of the ethyl(bcta-bromovinyl)-nalonic ester (IV) with

zinc dust and alcohol at 170 degrees to vinylethylmalonic ester (V).

arcszczmr / 2;: "

C-(Et)(CCCEt)2 ........>. gramme-(Etywocawa
(IV)
ma). 03:: Ii-C-(EtXCCCl—Et)2
(V)
The above reactions are somewhat wisleafiing in their singlicity for the
preparation of etly1(beta-bromov1ny1)-malon1c ester (IV). The cost favor-

dbl. conditions of reaction produced elong with (IV) an approximately equal

quen$1ty of e high-boiling, bromine-free tricerboxyllc ester. This compound

(20)

was shown to be 5,6,Crtricarbetioxyccstinc-fi (VIII), which has formed from

ethyl(betn-bronoviny1)-nslonic ester by the following reactions.

(.) BrCZtCEi—C-(EtXCCC‘Et)? ,1 Bit-OH -----—>- BrCEPCIi—fifi-fi‘CCE‘t
' t

 

0:6-(OEt)2
(VI)
(1:) BrCl‘d'JII-(fH-COOSt F ~> arose-omc-cocm
m. -t
(VII)
_/ _ GOEt CCEt
(c) BrCHj-CELiD-CCOEt ,6 Ixa C-(Et)(UCCEt)2 9 Et- -cn.,-c~.. -Et
"- kt (.30th
(VIII)

The orgin of the alcohol necessary for reaction (e) was uneleeinsble at
first since the reaction between 1,2-dibromoethene and sodio-ethylmelonio
ester hsd been carried out in absolute ether. But. s further insight into
the reaction involved in the formation of the sodio-etbylmalonic ester showed
thet only 77% of the theoretical quantity of hydrogen was evolved, thus 23%
of the sodium used had reduced the malonio ester instead of forming the
sodium derivative, which provided sufficient alcohol for the reaction to

take place in the formation of covpound (VIII).

Sorensen and Anderson (40) reacted two moles of sodio-phthslimidmalonis
ester with one sole of 1,2-dibromoethsne end obtained ethylene-Bis(phthelimid-
melanin ester). By using an excess of 1,2-dibromcethsne (41) end carrying
the reaction a step further, they obtained the lectone of bets-oxyethyl-
phthelimidnalonic ester. The lactone was believed to have been formed from
phthalimide(beta-broeoethyl)-melonic ester by the loss of ethyl bromide. No
attempts were made to isolate end characterize the slleged intermediate in

this experiment. (gamma-Iromopropylpbthelimidmslonic ester has been prepsred

(21)

by this method. Banner (#2) et el. carried out reactions involving the de-
hydrohlegenation of 2-phenyl-1-bronopr09nne and 2-phenyl-1-bromobutsne with
potassium aside in liquid sozonia to form largely unrearrenged olefins. The
reaction or 2-phenyl-l-bronebutsne in the presence of less than an equivslent
of potassium aside gave 2-phenylbutene-l, while the reaction of this bromide

with an excess of potassium snide yielded 2-phenylbutene-2 as shown below:

(excess bromide)

/ 63“

(2-phenylbutene-l)

 

CHx-Cfrg-CH-CHQ-B
a C(Hh ‘\\k(excess K-flflp)
. V "=9 CH

 

30' ‘23;

6-4 (2-phenylbutene-2)
The fornation of 2-pheny1butene-2 is explained on the basis of the prototropio
change of 2-pheny1butene-l, which was presumably first forred, the change to
2-phenylbutene-2 being brought about by the base.

Should a bromide be prepared which could be dehydrohsIOgenated to give
the corresponding olefin and possessed of 1 structure which would not permit
prototropic isomerization, one could introduce a vinyl group into the proper.
structure which would give rise to alphaeemino-beta-butenoic acid. Thus, it
was concluded that phthslimide(beta-bromoethy1)-diethylmelonste (XVIII) would
he 1 suitable compound to test this theory. The synthesis of (XVIII) may
be ecconpliebed by starting with diethylmalonete and preparing monobromo~
diethylmelonate (XV), which gives phthslimide diethylralonnte (XVII) when

condensed with potassium phthelimide (XVI). By prOperly designing and

carrying out the reaction it should be possible to condense 1,2-dibromo-

(22)

ethane with the sodio-deriwativs of (XVII) to give rise to (XVIII). However,
the stability of (XVIII) may prove to be a major factor. The dehydrohalo-
genstion of (XVIII) with potassium amide in liquid ammonia would give rise
to (XIX), which would forn.(XIII). (XIV), and (IV) upon hydrolysis. acidifi-
cation, and decarboxylation respectively. It would be necessary to use an
excess of potassium amide in the dehydrohaIOgcnation of (XVIII), since the
liquid ammonia would react with the ester to liberate ethanol which would
subsequently react with the potassium amide forming ammonia and potassium
ethylate, leaving no potassium amide to dehydrohslogenate the bromide. The
yield of (XIX) is also questionable, since the dehydrohaIOgenation reaction
will be competing with the formation of the corresponding azino compound.

The reactions involved are as follows:

 

 

005$ 003%
3-3 {81-2 -~ —~>H-Br
002% OOET
00\ (IV)
“fie/6H“ ,1 xon > x”<:>634
(m)
OOEt OOEt
H ‘3' " “‘<::>e“4 ......) “’}<>6HA
OOEt OOEt

(XVII)

com.
1' <>534
com
OOEt

«v- 406%

000m.

com.

00E?-

3 2%

(mg

33432.0?!”

CH

“A

00X
CHECK ~N32

COOK

OCH

CH ”CH

2" ““2

00H

(25)

com
I Ni .0.“ -—---§ a" «($3634
cont

/ srcngcnzsr --->

 

1‘ ma

,cucIw

 

cont
0
3:032an @634
cost

(XVIII)

Dung
CH2=CH 06%
om;2

(XII)
00X

OHé:CHC H2
K

(XIII)

OOH

CHZ‘ZCH Re
R

(m)

CHZ'ZOH-ggz-OOOH
(IV)

It was of interest to further the basic idea involved in the preparation

of (XI) and (IV), primary and secondary alcohol functions respectively. by

(2“)

replacing the formylaminc group with a phthalimide group, employing essentially

the some experimental eonditions. The reactions involved in the preparation

of the primary alcohol function are as follows:

OOEt

N: "' «(Iii/0634 f Br-CHz-Cfia-OH

com.

——>

 

c (-BOH)
“82.082 ‘. 6H4 ‘ww‘v w

 

at.
cazcn 0:):63‘ ,l xoa

 

 

2

OOEt
00K

03503 4112 / H01 2: u: w :5
00K
OOH

- (cog)

032.0?! 4182 - w A i

OOH

HO-CH 2482<f€> 631‘
CE“.

(XX)

003+.
CHZ'ICH Q 654-
com.

(111)
x

CHEER-ring
cox

(XIII)
a
03593 m2
3
(XIV )
cnzch—rcgz-cooa
(IV)

(25)

The reaeticns involved in the preparation of the secondary alcohol

funetion are as follows:

 

 

 

mm 1mm
H @6114 7‘ 035430 } Pyridine A org-g?! 4:)?“
com com.
(x111)
cont , cost
( ~ HOB ) 0
085-33 <:>6Hh A - ~ A A), cnzzca >634
COOEt com
(XXI)
com , cox
China-Q5114 / KOH __.....>. cagzcu 2
OOOEt cox
(x111)
00X 003
032203 4:32 I 801 A e > 0851511 «KHZ
‘ cox ' coca
(11v)
003
c5213 4:32 : (- 302 )__> cafes-5:300:33
con (IV)

Several methods have been employed for the introduction and protection
of an amino group on malonie ester in the synthesis of alpha-amino acids.

Redemann and Dunn (45) carried out a nitroeation reaction‘using butyl nitrite

(26)

and nalonic ester, with subsequent preparation of the acetylaminomalonic

ester (4h). The acetylation of the amino group gives a relatively poor yield
by this method. Galat (#5) used sodium nitrite and acetic acid in preparing
nitrosomalonic ester. Subsequent reduction of this compound, by the procedure
of Conrad and Schulse (#6), will give formylaminonalonic ester which may be
employed as an intermediate in the preparation of alpha-amino acids. Galst
(45) has employed formylaminomalonic ester as an intermediate in the synthesis
of amino acids. By using this intermediate one can enjoy several advantages;
higher yields, reduction of nitrosonalonic ester (II) to formylaminomalonie
ester (1) without having to prepare the N-derivative in a separate step. Thus,
it was felt that this intermediate (X) may be useful in the preparation of
formylamino(beta-hydroxyethyl)-diethylmalonate (11). Subsequent dehydration
of (XI) would give rise to foraylamino~vinyl~diethylmalonate (XII). providing
no structural rearrangements occured. Hydrolysis of (111), base catalysed,
would give the salt of amino-vinylmalonic acid (XIII). By liberating the
free acid (XIV), decarboxylation could be accomplished without too many dil-

ficulties forming (IV) as follows:

com Rt

H-H fNaONO/WQH-Rzo

mm own

(I!)

com. com
81-330 I Zn-dust / HCFTCH ”A R ~Nfl-CCH

cmm mm

(1)

OOEt
H ~NH-OOH

OOE‘L

cost
at '

-NH-COH

OOE‘t

OOOEt

”He-CH -NH-OOH

2
COM

003
CH? -NH-COH

OOEt

00K
CHER 4332
000K

H
OIL-.6 -NH
2

001‘!

(27)

I Hi .0131. ---—-->-

I Br-CH ~03 ‘ -0H

2

2

"-"€3’

 

I» xon

I HUI

 

(“002)

r—v—w—y—W

OOE‘t

Na - -NH-COH
OOEt,

OOEt

HO-CH2-0H2 423-003

Rt
(XI)

Et

(r‘

cnésca- eunacon
cost
(XII)
cox
032293 oaaz
cex

(XIII)

003
082.10%}! 2

COOH

(XIV)

N32

cages-enemas

(IV)

(28)

The major problem which will be confronted in this synthesis involves the
dehydration of the primary alcohol function without effecting the remainder
of the molecule. Further attempts were made to prepare a similar compound
which would undergo dehydration with greater ease. Thus, the dehydration

of foraylamino-alpha-hydroxyethyl-diethylmalcnate (XV), containing a secondary
alcohol function adjacent to a tertiary carbon atom, would g1ve rise to the
vinyl compound (XII). providing no molecular rearrangoent cccured. Subse-
quent hydrolysis, acidification, and decarboxylation of (XII) would give

rise to (IV) going through (XIII) and (XIV). The reactions involved are as

follows:

COL-It joost
a ‘H-OOH I CH -CHO I Pyridine ...; on ~03 ~NH-ccH

 

 

 

5 5 on
COOEt cost
(I) (I?)
lit cost.
( - HOB )
cafe org-con --~_ —: _ A e ‘2)- 032:0 .nn-cca
on
cmm mm
(111)
cost 001
,. _ - __ .
cares awn-cos I xoa >u cares 2
doom 1:
(am)
‘ 003
0112ch- ‘Nfig I H01 - e _ >s (Jazz-.0
cocx °°3

(XIV)

(29)

 

con
(- cc ) NH2
032434-5212 -— r - e gnu—9 CHZ'ZCH-CH-COCH
con (IV)

The limiting factors in the above synthesis may involve the extent and
rate which the aldol condensation between acetaldehyde and (X) will go in
the formation of (IV). Malonic acid readily condenses with aldehydes in
the presence of organic bases, but the methyl, ethyl, and propyl esters
would be expected to effect the condensation to different degrees, as well

as the substituted group.

(5°)

EXPERIMENTAL

AGROLEIN SYNTHESIS:
Experiment-l-as

A 2 l. two-necked round—bottom flask was equipped with a stirrer and
a dropping funnel so arranged that the stem almost touched the stirring rod.
Into the flask was placed 150 cc. of carbon tetrachloride, 66.6 cc. ( 1 mole)
of freshly distilled acrolein stabilized with hydroquinone. The flask was
placed in an icedwater bath, the stirrer started and 55 cc. (1.0) moles)
of bromine was added to the drapping funnel. A small stream of bromine was
allowed to flow until the addition‘was complete. The ice-water bath was
replaced by a water-bath and the dropping funnel replaced by a condenser.
The mixture was refluxed for one hour. leaving a pale yellow solution. The
earbon tetrachloride was removed by distillation under reduced pressure.

The product. l.2-dibromopr0pionaldehyde, was distilled over at Séf/lem.
giving a pale yellow fuming liquid.

Ammoniun.chloride(59.0 g.) was dissolved in 185 cc. of water. cooled
to 6,, and combined with the l,2-dibr0mopropionaldehyde obtained above
(0.79 mole). The flask was provided with a mechanical stirrer and placed
in an ice-water bath. The stirrer was started and a solution containing
49.0 g. of NaCN dissolved in 140 cc. of water, previously cooled to 16’,
was added a few milliliters at a time so that the temperature did not exceed
66’at any time. The mixture was stirred one hour after the addition of the

RaCN solution had been completed, then the ice-water bath was removed and

the stirring continued two hours at roon.tenperature. a reddish sirup had

(31)

began to settle out at this point. The flask was steppered and allowed to
sit at room temperature twelve hours. The reaction mixture was strongly
acidified with hydrochloric acid and evaporated under reduced pressure to
about 550 cc., than an equal volume of concentrated hydrochloric acid was
added to the concentrate and refluxed for one hour; The mixture was then
evaporated almost to dryness in a round-bottom flask with constant mechanical
stirring, at about 116: then heated to l2d’for a period of thirty minutes,
leaving a dark viscous mass. This mass was extracted with a mixture of metha—
nol-ethyl ether (1031) using 200 cc. portions, leaving a large amount of
salts. The extracts were combined, filtered, and evaporated to dryness,
giving a brown, gummy, semi-crystalline residue. The residue was extracted
with several 25 cc. portions of hot water, leaving a black resinous mass.

The hot water extract was heated to led’and treated with powdered basic
lead carbonate, in small portions, until effervesence ceased. The mixture
was cooled to about é’and filtered. The red filtrate was treated with 325
to remove the lead. The lead sulfide was filtered off under a slight vacuum.
then filtered under the influence of gravity. The red filtrate was evaporated
on the steam-bath until crystals began to;fcrn, then transferred to a beaker
and allowed to cool. The crude crystals were filtered off and the filtrate
was again evaporated on the steam-bath as before, cooled, filtered, and the
crude crystals combined. The residue was washed three times with absolute
alcohol and the crystals collected by centrifugation. The filtrate was
evaporated again giving more crystals, which were washed with absolute alcohol

and combined with the above. The crystals were dissolved in the minimun

(52)

volume of water, treated with Norite, heated to boiling, allowed to stand
for ten minutes, and filtered. The filtrate was evaporated on the steam-
bath until crystals began to form, cooled throughly and filtered. The crys-
tals were washed with absolute alcohol three times using 10 cc. protions.
The filtrate was evapcrated to about two-thirds of its volume, allowed to cool
and more crystals formed. The white crystalline compound was very soluble in
water, very slightly soluble in absolute alcohol, and insoluble in acetone
and ether. The compound possessed both nitrOgen and bromine.

Anal. found: a. 15.5% (mero-Kjeldahl)

calcd. for ChH7OéNBr28 N, 5.56%

The crystals were dissolved in dilute hydrochloric acid and evaporated
to almost dryness. The residue was extracted with ten 25 cc. portions of
methanol-ethyl ether (lOsl) solution. The residue obtained upon evaporation
of the extract was dissolved in 300 cc. of water, heated to 106: and treated
3

2
and filtered. The filtrate was evaporated on the stems-bath until crystals

with basic lead carbonate as before, cooled throughly and treated with B

began to form, cooled, and the crystals filtered off. The nitrogen content

of the purified crystals was 14.1%, less than the original by 1.2 %L

Experiment-l-bs

A 2 1. two-necked round-bottom flask was provided with an efficient
mechanical stirrer, and a long stem dropping funnel with the stem about
three or four centimeters from the bottom of the flask. The equipped flask
was placed in an ice-dry ice~bath. Into the flask was placed 250 cc. of

001“ and 250 cc. (5.45 moles) of acrolein stabilised with hydroquinone

K39)

(freshly distilled). 190 cc. (5.58 moles) of bromine was placed in the dropp-
ing funnel. The stirrer was started and a small stream of bromine was allowed
to flow into the mixture until the addition was complete. The cold-bath was
removed and the mixture refluxed for ten minutes. The reaction.mixture was
then concentrated under reduced pressure until free of carbon tetrachloride.
The product, 1,2-dibr0mopropinnaldehyde, was distilled over at adrllamm.
giving a pale yellow liquid. 578.0 g. (1.75 moles) of dibromoacrolcinweere
added to a flask equipped with an efficient mechanical stirrer and placed
in an ice-dry ice-bath. The stirrer was started and the dibromoacrolein
cooled to -5: then a solution containing 187.25 5. (5.5 moles) of KHhGl
dissolved in 550 cc. of water, cooled to 0, wae added. The mixture was
stirred vigorously for 15 minutes and a solution, previously cooled to ~15.
containing 171.4 g. (5.5 moles) of NaON dissolved in 550 cc. of water was
added at a rate so that the temperature remained below 25’(about two houre).
The stirring was continued for three hours at room temperature. then the
flask was tightly stoppered and allowed to stand for 1h hours. The reaction
mixture was strongly acidified with H01 and evaporated to about 850 cc. In
equal volume of concentrated H01 was added and the mixture refluxed for three
hours. allowed to stand 12 houre and evaporated almost to dryness. The residue
was extracted with 5.5 1. of ethyl ethernmethanol (lot) in 200 cc. portions
to remove the hydrochloride of the dibromo-amino acid.

The extract was evaporated to approximately one-half its volume and a
volume of watet equal to the volume of solvent removed was added. Thie process

was continued until most of the organic solvent had been removed. The water

(31+)

solution of the material was treated with Korite. brought to the boiling
point, allowed to stand for 15 minutes, and filtered. The filtrate was
heated to loa’and treated with basic lead carbonate until effervescence
ceased. The mixture was throughly cooled and filtered. The filtrate was
treated with B28 and filtered. The filtrate was evaporated on a steamrbeth
to about #50 cc.. and four volumes of absolute methanol was slowly added to
the hot filtrate, giving rise to a gelatinous precipitate upon cooling.
The mixture was filtered and the filtrate evaporated on the steam-bath until
crystals began to form, cooled, and the liquid decanted. The precipitate
was washed with cold absolute alcohol until most of the red color had been
removed. The evaporation of the filtrate with subsequent cooling was con.
tinued as long as crystals could be obtained which could be washed free of
the reddish-brown material with methanol. Care was taken after the second
evaporation of the filtrate to prevent a very impure product from precipi-
tating. The precipitates were dissolved in the minimum volume of hot water
and filtered into five folumes of absolute alcohol. Crystallization of a
white substance occured upon cooling. The material was recrystallised
three times and subjected to nacro-Ijeldahl nitrOgen determination.

Anal. found: N. 12.34}

calcd. for 043702N3r2' N. 5.56;

Ekperiment-l-cs
A 2 l. two—necked round-bottomed flask was equipped with an efficient
mechanical stirrer and a long stem dropping funnel so arranged that the

stem was extended well below the surface of the liquid. Into the flask

(55)

were placed #00 cc. of 061 and 112.12 3. (2 moles) of acrolein stabilised

a
with hydroquinone (the acrolein used in this experiment was not distilled,

since former experiments gave evidence of considerable polymerisation even

when specific psecautions were taken to prevent excess heating during the
distillation). 106 cc. (2.06 moles) of bromine were placed in the dropping
funnel. The stirrer was started and a small stream of bromine was allowed

to flow until the addition was complete. The reaction.mixture was concentrat-
ed under reduced pressure, using a water-bath at #5; until the 0014 was removed.
The product, 1,2-dibromoacrolein, was distilled over at Sff/lSmm.

118 g. (2 moles) of NHACI and 98 g. (2 moles) of KaGN were dissolved in
the smallest volume of water and cooled to -16; then placed in a flask provided
with an efficient mechanical stirrer. The stirrer was started and 216 g.

(1 mole) of dibronoacrolein and sufficient methanol to get it into solution
were added. The temperature remained below 00 for a few minutes, then it rose
sharply to a very high temperature with subsequent formation of a turbid
system, followed within a few minutes with the formation of a dark heavy
sirup which settled out on standing. The reaction mixture was allowed to
stand at room temperature for nne hour before the product was extracted with
ethyl ether. The ether extract was dried over anhydrous magnesium.sulfats
and filtered. The filtrate was concentrated under reduced pressure at room
temperature to remove the ether. leaving a dark heavy sirups

The sirup was divided into two equal parts and subjected to both acid
and base hydrolysis. The hydrolysate from the base-hatalyzed hydrolysis
was made acid with hCl and both reaction mixtures were worked up using

the same procedure employed in eXperiment-l-b. A dark resinous material

 

 

(56)

resulted from thie Operation which failed to give a Euro product as a
result of several crystallizatione.
Anal. fmmd’ N. 15.27.:

CfilOde for 0487027531‘23 N, 505(%

Experiment-Q-e:

A 2 1. two-necked round-bottcntfleek wee eqnipped with e mechanieel
stirrer end e thermometer. Into the flask were placed 1350 cc. of anhydroue
ethyl ether, 66.6 00. (1 mole) of freshly distilled acrolein, and 120 g. of
gleciel ecetie acid. The fleek wee )leced in en ice-bath, the stirrer was
started end allowed to continue throughout the reaction. 98.0 g. (2 melee)
Of'NeCN end 117.6 g. (2.2 moles) of 33401 were mixed well by grinding to e
powder. This mixture of HaCN end fiHhCl nee added to the content of the
fleck over a period of two houre. A.fev milliliters of water (10 to 15 cc.)
were edded to initiate the reaction. The temperature was kept between Kit.
Goduring the addition. The mixture wee permitted to sit over night in the
ice-bath without reviving the bath. The stirring wee continued the next
morning at room temperature for three houre, giving a total reaction time'
of 24 hours. By this time the solution poaeoeaed an intense yellow eolor.

The yellow ether solution wee decanted from the solid material, which
wee extracted with two 250 cc. portions of ethyl ether and then with
acetone until most of the yellow color wee removed. The extracts were
combined, filtered, and dried over anhydrous magnesium sulfate. The filtrate
we: evaporated on the steam-bath until the ether was completely removed.

A dark resinous mass resulted which did not add bromine or decolorixe e

(37)

solution of KHnOh.

Egreriment-2-b:

A 2 1. two-necked round-bottom flask was equipped with a mechanical
stirrer end e thermometer. To the flask was added 117.6 g. (2.2 roles)
of NH401 dissolved in 500 cc. of water, h5.0 g. of glacial acetic acid,
66.6 cc. (1 mole) of acrolein stabilized with hydroquinone, and sufficient
methanol (100 cc.) to dissolve the ecrolein. The flask was placed in e
dry ice-methanol-hath, the stirrer was started, and the mixture cooled to
~26: 98.0 g. (2 moles) of NeCN was dissolved in 400 cc. of water and added
to the cold mixture with vigorous stirring. The NaCN solution was added at
euch e rate that the temperature was maintained between Zdabelow zero and
~15 (required about 35 minutes). it the end of the He‘ll”: addition the man:
In! removed from the dry ice-methanol-bath until the temperature of the
reaction mixture reached «2, then it was placed in an icedwater bath. The
nixture was stirred vigorously for six hours, with a maximum temperature of
i: then two more hours at 5: then allowed to stand at room temperature for
three hours. The yroduct was extracted with ethyl ether and dried over
enhydroue magnesium sulfate, then filtered. The filtrate was concentrated
under reduced pressure until it was free of ether, using a water-bath just
warn.encugh to prevent cooling as the ether evaporated. A sirupy yellow
eubetence resulted, however, a resinous substance resulted within enohour -

vhich did not add brorine or decolorize a solution of XFnOA.

(33)

Experiment—)3

 

1 5 1. two~necked round—bottom flack was equipped with an ifficient
mechanical stirrer and a dropping funnel. Into the flask were placed
347.2 g. (6.2 moles) of acrclein stabilized with hydrcquinone, 3.2 1. of
dry ethyl ether, and 513 g. of glacial acetic acid. The stirrer was started,
then #30 g. (8.7 moles) of powdeded NaCE was placed in the dropping funnel
and euepended in dry dthyl ether and added over a period of two hours. a
few milliliters of water (Ste 10 cc.) were added to initiate the reaction.
The stirring wee continued for nine hours at room temperature after the
addition of the NaCR had been completed. The reaction mixture was filtered
under a slight reduced pressure. The salts were washed twice with 800 cc.
portions of dry ethyl ether. The straw-yellow ether solution was filtered
again (gravity). The filtrate was concentrated under reduced preeeure te -
-remove the ether and other volatile solvents. The temperature of the water-
bath did not exceed 65,6uring the porcesc of concentration. The resulting
yellow oil was subjected to a much lower pressure by eanOying a highs
vacuum punp. Vinylglycolic nitrilc boils at 65f/120mm.,but it was learned
from.former experiments that a great deal of polymerization occured under
theee conditions, therefore the crude compound was used. #66.0 g. of crude
vinylglycolic nitrile were obtained from the 3&7.2 g. of acrolein.

1 one-liter two-necked round-bottom flask was equipped with a thence-
meter, mechanical stirrer. and two dropping funnels eo arranged that the
tips were very close to the etirring rod. The flack was placed in an ice-
salt water-bath. To the flask was added 166 g. (2 moles) of crude vinyl-

glycolic nitrile which was diluted in two volumes of dry ethyl ether.

"5
\M
\O
V

238.0 g. (2 moles) of 80019 and 158.2 g. (2 moles) of yyridine were added

to the two dropping funnels. The stirrer was started and a temperature of
a

v5 were obtained before the addition of $0012 and pyridine was started.

There was always a slight excess of 8001 in the reaction flack. fly the

2

end of this addition the temperature of the reacting mixture had reached

25: Every drop of pyridine produced a turbidity which turned dark rapidly
and acquired a airupy characteristic. The mixture nae allowed to stand

for one hour in the cold bath with etirring, then treated cautiously with
200~cc. of water and extracted with ethyl ether, dried over anhydroue an‘
hydrous magnesium sulfate, and filtered. The filtrate was concentrated
under reduced pressure. using a water-hath at a temperature not greater
than 50: to rerove the ether. 80.0 co. of a dark brown liquid, crude alpha-
ohloro derivative of vinylglycolio nitrile, resulted which wae not distilled
to prevent further polymerization.

The crude compound obtained above (80.0 5.. 0.79 mole) was combined
with 277.6 g. (1.5 moles) of potassium phthalimide and heated on the steam-
bath for six hours, then heated for one hour in an oil-bath at 150: The
reaction mixture was cooled and treated with 200 cc. of water. A water
insoluble dark resinous mace remained in the vessel which was insoluble in

alcohol, acetone and other, and was therefore abandoned.

(a)

KiLCTi-IC sates arm-sore:

 

Experiment-h:

Forrylsninomqlonio ester.- To a mixture of 152.C cc. (1 mole) of freshly
distilled ethyl nelonste and 170.0 cc. (5.0 moles) of glacial acetic acid
was added a solution of 190.0 g. (2.75 moles) of sodium nitrite in 275 cc.

of water. The mixture was stirred during the addition of nitrite and main-
tained below 20: After the addition had been completed, the nixture was
atirred for on sdditionsl four and one-half hours at room terpersture. The
product, nitroceunalonic ester, was extracted with chloroform and the solvent
removed 12 33233 on s water-bath. The residue, a yellow oil amounting to
about 185.0 5., was dissolved in 300 cc. of technical ferric acid (90;), and
the mixture was transferred into a three-necked flask provided with a thermo-
nerer, a stirrer, an. a reflux condenser. A small enount of technical sinc~
dust was added and the mixture was stirred and heated until the reaction
started. There was an induction period for several minutes after which the
reaction proceeded vigorously, unless only a small amount of zinc-dust was
present at this stage. 150.0 g. of zinc-dust was then added through the
condenser at such a rate that t’e temperature was maintained betunln175~3§
without external heating. After the addition of zinc-dust had been comyleted
(twenty to thirty minutes), the mixture was filtered hot, the filter-cake

of zinc-formats throughly washed with foggic acid and the filtrate evaporated
35,1222? on a water-bath. The residue, which was an oil containing a small
quantity of zinc-formats, was fractionslly distilled 32.12229 and the fraction

0
boiling between 150 and 132 at 2-5 mm. of mercury was collected. It solidified

\“u 1

into a white crystalline mass which had a melting noint of h3-h5: the yield
was lO#.O g. (51.2%).

Note: One may find difficulties in fractionating the residue left after

the volatile solvents have been removed, however, this may be overcome by
employing the following method. The residue to be fractionated is placed

in a pyrex poundvbottom flask (not over 5C0 cc.) and joined to a Claisen
distillation head which is connected to an adaptor designed for vacuum distil-
lation. The system appears to be most efficient when the reciving flask is
not larger than 250 cc. The apparatus is connected to an espiratcr uhich
will reduce the pressure to 12-15 cm. of mercury. The temperature of the
oil-bath is gradually increased until it has reached 145: The aspirator is
allowed to operate at maximum efficiency with the oil-bath at 140° until .11
substances which will distill under these conditions have teen removed

(total time was three to four hours). The reaction.flask is removed from

the hot bath, allowed to cool, and the vacuum is released. The second fract~
ion is collected by connecting the apparatus to a high-vacuum pump (properly
connected to an acetone-dry ice trap) and allowing it to evacuate the system
to its maximum ability, hen the temperature of the oil-bath is slowly incre-
ased until the fraction immediately below the one desired to be collected is
completely stripped off, that is, this fraction is taken up to 12§oet 2-5 mm.
The reaction flask is cooled before the vacuum is released. The third fraction
will be that of the range desired, 15C- to 15205”. 2-5 mm. It is Very inportant
that the pure have evacuated the system to its maximum ability before heating
of the reacting flask is started, then the proper adgustments of pressure

and temperature are made. The fact that a fiery dark material in thd reaction

 

(42)

flask appears should not be interpted that the compound desired has decom-
posed, the dark eateriel is mostly due to zinc ferrete decoeyosition, etc.
Sadie—formylaminoralonic ester.- 5.66 g. (0.25 mole) of he were dissolved

in #72 cc. of absolute ethanol, to which 53.0 g. (0.25 mole) of formylamino-
malonio ester were slowly added with stirring. One-liter of benzene was

added to the mixture and distillation was continued until one-liter of benzene-
cthanol azetrope distillate had been obtained, tlen more benzene was added

and the distillation continued in this way until the residue was completely
free of ethanol, leaving the sodio-forzylaminomelonic ester suspended in

250 cc. of benzene.

To this suspension was added hC.O g. (0.3? mole) of ethylene bromohydrin
and s few crystals of Eel. The flask was provided with a condenser equipped
with s CsCl2 tube to prevent moisture from entering and allosed to react at
room temperature for 59 hours. A pals yellow solution resulted and a large
amount of salt settled out. The reaction mixture was filtered, and the sslts
rushed with anhydrous ethyl ether. The filtrate was concentrated under ro-
duccd pressure, in a nitroEcn atmosphere, to remove the benzene and unreactcd
cthylcnebronohydrin, leaving s pale yellow 011. 50.5 g. of the pale yellow
oil were dissolved in seven volumes of benzene and refluxed over 22.1 g. of
9205 for four hours. The flask was provided with a condenser equipped with
n Cs012 tube to prevent moisture from entering. The reaction mixture was
fractionated under reduced pressure. The first fraction consisted of benzene
snd 1 small snount of water, and the second fraction consisted of other

VOlstile substances, leaving I solid residue. Ksither one of the fractions

TI
3

 

#17...— s

(’6)

or residue would add bromine or decolorize Kflnoh solution. Thus, s more

accurate fractionstion.was not conducted.

Ergerimentffip

An ethereal solution of acetaldehyde was prepared by heating an excess
of paracetaldehyde with e few drops of sulfuric acid (1.5 cc. of cone. H2804
{:1
end 1.) cc. of water) in e water-bath. The evolved aceteldehyde was passed f““'

umverd through s short inclined condenser to remove any parecetaldehyde. E

It was dried by passing through u tube eonteining 6e012 and collected in 80 cc.

 

of dry ethyl ether cooled by en external bath of ice~bsth.

To this solution were edded #9.0 g. (0.2# mole) of formylaminomnlonie
ester end h9.0 g. of pyridine. The mixture was kept for two days at élsnd
then one day at room tempereture. The ether and pyridine were removed by.
distillation under reduced pressure, using a water~bath st 36:"lesving en
elmost white residue. The product was erystsllised several times by dis»
solving in the minimum volume of hot benzene end adding high-boiling ligroin
(d, 0.72-0.74) until a permanent oloudynees occured, then placed in the
freezingocompsrtrent of s refrigerator for crystallization. The yield we:
26»O g. of e corpound which possessed e sharp melting point of 49-55:

lnal. found: C, 47.96: H, 6.50; II, 6.77

£7.88 6.27 6.15
cslcd. for Glofil GIN O, k8.55; H, 6L9); N, 5.66

7 o
A 250 cc. round-bottom flask was equipped with a condenser provided
with e 0:012 tube. Into the flask was placed 5.0 g. of P905 and 2.0 g. of
alleged alpha-hydroxyethylfornyleminomslonic ester dissolved in 100 cc. of

ethyl propionate, and refluxed for three hours. The liquid was decanted

(At)

fror the solid material and fractionated under reduced pressure. The fraction
containing the product gave a positive Bayer's test for unsaturetion. Ho
citrrpts were made to carry out the next series of reactions to arrive at
,alphs-amino-beta-butcnoic acid or even characterize the substance which gave

the above test, since only trscos of the material more present.

ggperimenteé—a:

Ethyl monobrocomslonate.- A 5 l. three-necked round-bottom flask was fitted
with a stirrer, a reflux condenser, and a separatory funnel with the stem
extended far enough to be below the liquid surface. The condenser was equipped
with a tube leading into a container to trap most of the Ear gas which would

be evolved during the reaction. In the flask were placed 1120 g. (7 moles)

of freshly distilled diethyl malonate and 1050 cc. of 001“. 371 cc. (ILZI
moles) of bromine was placed in the separatory funnel. The stirrer was started,
and a small volume of bromine was run into the solution. The flask was heated
by means of s heating-contel until the reaction started. Then the remaining
volume of brorine was added gradually at such a rate as to keep the liquid
boiling gently. It was then refluxed until no sore HBr gas woe evolved (about
1.5 hours). The rixture was cooled and washed five times with 550 cc. portions
of fifiiflsgcofi solution. It was then distilled under reduced pressure, frectione
being taken up to 1369/h0 rm. and st 130-1550/40 mm. The lower boiling
fraction was redistilled. The fractions boiling at 150-1550/40 mm. were
combined and redistilled under reduced pressure. The product boils at 132-

0
156 /53 mm. (121-125a/16 mm.), which amounted to about 1250 g. (75.77% yield).

(#5)

Potassium phthalinidew .200 g. or phthalinide were dissolved in h 1. of
boiling hot absolute methanol by heating in a 5 brand-bottom flask on

the steam-bath. To this hot solution 76 g. of XOR, dissolved in 500 cc.

of 75% methanol. was added slowly with stirring. The final solution was
cooled at once and the potassium phthalimide which precipitated was filtered
off. To this filtrate was added another 200 g. of phthalimide and dissolved
by heating on the steam-bath, and imediately upon effecting this solution.
76 g. of KCH dissolved in 500 cc. of 75% methanol were added slowly with
stirring. The solution was cooled, and the potassium phthalimide filtered
off. The two portions of potassium phthalimids were combined and washed with
acetone to remove any now-reacted phthalimide. This procedure gave 85-88%

yield of the product on the basis of the #00 g. of phthalimide used.

Phthalimide diethylmalonate.- 550 g. (2.97 moles) of potassium phthalinide
and MO 3. (1.42 moles) of nonobrcmomalonic ester were combined, well mixed.
and brought to lhooover a period of twenty minutes. The yellow mass was
heated for one hour at a temperature between 11350150q , with constant stirring.
While the content of the flask was hot it was poured into a large beaker and
dissolved in 2.5 l. of boiling-hot 50% alcohol, crystals appeared upon cooling.
The crystalline mass was washed with 2 1. of water. The product was purve-
rised in a large mortar and added to a beaker containing water. then filtdred
\mder auction. The product was washed three noEtines with water and filtered
under suction, and drying was accomplished by allowing the product to remain
under suction. 518 g. (92% yield) of phthalimide diethylmalonate was obtained

The compound possesses a faint yellow color, but almost gave a colorless solution

 

(*6)

in benzene and alcohol. This degree of purity vac obtained from the compound
by dieeolving in warm methanol and elowly adding water until the proper cone

ditionc for cryetallization.wee reached.

Bodio-phthalimide diethylmalonate.- 25.0 g. (1 mole) of Na were dissolved

in 900 cc. of abeolute ethanol, tovhioh were added 505.1} g. (1 mole) of
phthelimide diethylmalonete and 1.5 l. of benzene. The mixture was distilled
until one liter of benzene-ethanol azetrope wee collected. This vac contin~
ued until all traces of ethanol had been removed, and finally all of the

benzene wee difltilled off leaving a dry yellow substance, eodio-phthalimide

i

diethylnalonate. A 2 l. round-bottom flask was provided with a condenser
equipped with a 051012 tube. To the flack were added 158.2 g. (0.58 mole)
of eodio-phthalimide diethylmalonate, 921.2 g. (4.9 moles) of 1.2-dihromo-
ethane, and one liter of benzene, then heated on the steam-bath for 75 hours.
The reaction mixture wee cooled, and filtered under auction. The recidue
wee vaahed twice with 100 cc. portions of‘lry'ethyl ether. A futher insec-
tigetion of this residue revealed that it vac largely unreaoted eodio-phthal~
imide diethylmalonnte with a small quantity of inorganic bromide. The fil-
trate was concentrated under reduced pressure, using a water-bath, until
the ether, benzene, and unreacted 1,2-dibromoethane was removed, leaving
a dark residue.

Upon crystallization of thie residue phthalimide die hylmalonate wee
recovered, and a very emall amount of an organic bromide. Thus, the reaction

proceeded only to a very alight extent when hen-one was empIOyed as a eolvent.

(#7)

Inperinent-é-hs

This experiment is a reproduction of echriment-é-a in the preparation
of the sodio-phthalimide diethylmalonate.
Phthalimide(beta-bromoethyl)-diethylmalonate.- To a 5 l. round-bottom flask
equipped with a condenser provided with a CaClz tube were combined 527.0 g.
(1 mole) of sodio-phthalimide diethylnalonate, 517 cc. (6 moles) of 1,2-
dibromoethane, and 2 l. of high-boiling ligroin. The mixture was well
nixed and heated on the steanebath, with occasional stirring. for 24 hours,
then cooled and filtered. The lumpy residue was ground to a powder, using
a.mcrtlr and pectha and returning to the flask and covered with 5 moles of
1,2edibromoethane and the filtrate. floating on the steam-hath was continued
for 96 haurs more, then filtered while hot. The residue was washed twice
with 200 cc. portions of dry ethyl ether. Crystals began to form as the
filtrate cooled. The mixture was filtered giving residue-l. The filtrate
was concentrated under reduced pressure, using a water-bath between 75-60,
to about #50 cc. Upon cooling more crystals settled out, which were filtered
off under suction giving residue-2.

Residues.» l and. 2 were coabined and washed with two 200 ... portions
cf dry ethyl ether and dried under suction, leaving 15.5 g. The resulting
residue was found to be unreacted sodio-phthalimide diethylnalonate. The
filtrate was concentrated under reduced pressure. using a water-bath at
90.95: leaving a heavy reddish oil weighing 229.5 g. The oil was distilled
Her reduced pressure eftee unsuccessful attempts were made‘to crystalline

it. An overall fraction.was distilled over, using an oil-bath, up to

 

 

(“8)

e
210 / 1-3 m. leaving 25 g. of a black tar residue. The dictilhtc was

fractionated giving the following fractions.

 

fractions B.P. (#0.) weight Sggs.)
1 41671-3 n. 21.5
11 154462716 m. 26.1
111 166-1669/1-5 mm. 115-7
IV ‘black tar residue' 60.0

Fractions 1. II, and III were clear oils which crystallized on standing.
Fraction III was crystallised from benzene and high-boiling ligroin, which
gave 56.) g. of a white compound, n.p. 759(uncorrected), which was broninc-
free. The compound was soluble in ethyl ether, dimethyl ketone, alcohol.
benzene, insoluble in water, and high-boiling ligroin.

Anal. found: 0, fiche} H. 5001’ H. 5e51,, 'NO Bromine'
$9.45 #.96 5.59

The heavy oil. alleged phthalimide(beta-bromoethyl)-diethylmalonate,
contained bromine and nitrogen but was not characterized quantitatively.
Fractions 1. II. and 111 did not contain bromine. Thus, the compound

decomposed when subjected to the conditions used in the fractionation.

ggperinent-G-cg

lbs sodio-phthalimide diethylmalonate was prepared by the same procedure
employed in experiment-é-a.

To the flask were added 138.2 g. (0.53 mole) of sodio-phthalhnide
disthylmalonate and 1 Kg. (5.} holes) of 1.2-dibromocthane, then heated on

the stealrbath. with occasional stirring, for 122 hours. I‘large amount

(59)

of salt settled out and the liquid possessed a deep red color. The content
of the flask was cooled thrOughly. filtered under suction and gravity respec-
tively. The filtrate was lancentrated under reduced pressure. using a water-
bath at 85: leaving 100 g. of a heavy red-brown oil which contained nitrogen
and bromine. The heavy oil, alleged phthalimide(beta-bromoethyl)-diethyl-
malonate. failed to crystallize from a number of solvent systems.

Lfiguld‘fihs was prepared by passing anhydrous NH

5
(the container was provided with a CaCl2 to keep out moisture). using dry

gas into a Dewar flask

ice-acetone as the cooling agent. 5.74 g. (0.096 mole) of clean K and a few
small pieces of rusty wire gases were added to 200 cc. of liquid NH) and
allowed to stand, with occasional shaking, until dissolved (about 1.5 hours).
5.0 g. (0.012 mole) of the heavy oil were dissolved in 50 cc. of anhydrous
ethyl ether and added rapidly, with shaking, to the solution of KéNHz

(0.096 mole) in liquid ammonia. The reaction flask was provided with a

CaOl2 tube and allowed to react in the Dewar flask for 18 hours. The reaction
mixture was poured into an evaporating dish and allowed to remain at roo-
temperature until all of the liquid ammonia had evaporated leaving a
yellowish powder. Containers which will permitd the concentration of ammonia
gas to build up should be avoided during this evaporation, since a conesne
tration of 15 to 20% of NE, in air is explosive. This powder was treated
with water cautiously, using a medicine dropper, until certain that all
excess K-NH: had reacted, then enough water was added to dissolve the amide
and filtered under suction. giving a straw-colored filtrate and a residue

which.wss washed with cold water. The white residue did not add bromine

(50)

or decolorize KMnOh solution. The straw-colored filtrate was combined with
an equal volume of concentrated KCH solution and gently refluxed until ammonia
was no longer evolved (about 5 hours). The reaction.mixture was cooled to
10° and neutralized with 6 N sulfuric acid. previously cooled to 09. The acid
was added dropwisehvith the container in an ice-bath so that the temperature
could be maintained below 55: A white substance, water insoluble, settled
out. The material was filtered off under suction and washed twice with 15 cc.
portions of cold water. The white substance was phthalic acid. The filtrate
was adjusted to pH 7 more accurately at this point and concentrated under
reduced pressure using a water-bath at #5: (it was found that the correspond-
ing malonic acid would undergo decarboxylation at about éé’in acid media),

to 20 so. The salts which separated out were filtered off under suction.
giving a straw-colored filtrate, The neutral straw-colored filtrate. alleged
amino-vinylmalonic adid solution, was made acid with one drop of 6 R hydro-
chloric acid and placed in a ‘ter-bath at 60-650until 002 was no longer
evolved, as shown by a white precipitate of Ba005 when the gas was passed
into a saturated Ba(OH)2 solution. The resulting solution was cooled to

room temperature and neutralized to pH 7, then cooled to 6: More salts
separated out which was filtered under suction. The filtrate added bromine
and dccolorized a xenon solution at room temperautre within one minute pro-
ducing a brown precipitate, and gave a positive ninhydrin test. The filtrate
which gave the above tests, a solution of alleged alpha-amino-beta-butenoic
acid. was concentrated to about one-halt its volume and placed in the ice-

box. This stimulated the precipitation of more salt. This process of

(51)

concentrating the filtrate to remove a few milliliters of solvent and
cooling was continued until the crystals which separated out gave a slight
positive test for unsaturation with KMnOh solution.

The resulting filtrate, homoserine, and threonine were subjected to

paper chromatography using 6' X 22‘ strips of Hhatman § 1 paper.

ltpesimentejz

Sodio-phthalimide diethylmalonate was prepared by the same procedure
employed in eXperiment-é-a.

A 500 cc. round-bottom flask was equipped with a condenser provided with
a OaCl2 tube. To the flask was added 165.5 g. (0.5 mole) of sodio-phthalimide
diethylnalonate, 100 g. (0.6 mole) of 2-bromo-l-ethanol, and a few crystals
of NaBr. The mixture was heated on the steam-bath 49 hours, with occasional
shaking. The reaction mixture was cooled and extracted with four 500 cc.
portions of dry ethyl ether and filtered. The filtrate was concentrated
under reduced pressure to remove the ether, then the temperature of the
water-bath was increased to 50. and the concentration continued until the
unreacted 2vbromo-l-ethanol had been removed. The residue, 2.7 g. of an
oil, was dissolved in 150 cc. of benzene and added to a 250 cc. round-batten.
flask, equipped with a condenser and OaOl2 tube, containing 10.0 g. of P205
and slowly refluxed three hours. The reaction fixture was cooled, filtered,
and the residue extracted with two 100 cc. portions of dry ethyl ether. The
filtrate and ether estracts were combined and concentrated under reduced
pressure until all benzene and other had been removed. The iceidus, alleged
phthalimide-vinyl~diethylmalonate, did not add bromine or decolorise KMn04

solution.

Fxperiment-B:
. An ethereal solution of excess acetaldehyde was prepared by the same
method employed in experiment-5.

To this solution were added 76.) g. (0.25 mole) of phthalimide diethyl-
malonate, and pyridine. The mixture was kept for three days with a maximum
temperature of l§.and finally one day at room temperature. The reaction .
mixture was subjected to a vacuum distillation, using a water-bath at 55::
to remove the ether and pyridine leaving a dark oil and some solid material.
The mixture was filtered and the residue (70.5 g.) was characterized, aftér '
three crystallizations, on the basis of the nitrogen content derermined 4
by the macro-Kjeldahl method. The dark 011 failed to give a crystalline pro-
duct from various solvent systems and decomposed upon distillation attempts
at 1-) mm. of mercury. 2.0 g. of the oil was dissolved in 100 cc. of benzene
and refluxed over 5.0 g. of P205 for three hours. Thr reaction.mixture was
cooled and the solution decanted from the residue, which was washed with
two 50 cc. portions of dry ethyl ether. The bensene solution and ether
extracts were combined, filtered, and concentrated under reduced pressure
until the residue was free of benzene and ether. The residue failed to add

bromine or decolorize KKnO solution.

1,

(53)

DISSCUSSICH AND RESULTS

In experiment-l-a l.2-dibron0propionaldehyde was prepared by the
bromination of acrolein in G3Cl#.'”0uring the removal of the 001A the reaction
mixture often reacted gigcrcusly giving a dark brown brittle polymer. This
behavior may be explained as follows; the 0014 being removed by distillation
cOntained unreacted bromine which probably took part in a substitution reaction
liberating HBr in the system, catalyzing the polymerization of the aldehyde.
HydrOgen bromide gas will promote the polymerization of the aldehyde (acrolein)
even at zero degrees. This was avoided by starting with acrolein which possess-
ed the minimum degree of polymerization and would add the theoretical amount
of bromine. The dibromoacrolein was subjected to the conditions employed by
Baker and Skinner (55) in their modification of the original Strecker synthesis.
A‘white crystalline compound was obtained which contained both nitrogen and
bromine. The percentage nitrOgen found was 15.5%5 while the calculated for
alpha-amino-beta,gammaodibromocyanohydrin was 5.56%} The compound was found
to be mostly ammonium salts. Further crystallizations failed to give a pure
compound. It is felt that the aminocyanohydrin.was only formed to a very
slight extent.

The lower temperature employed in experiment-l-b did not improve the
product any. Experiment-l~e employed the Zelinsky and stadnikoff (3#, 55)
modification of the original Strecker (#7) synthesis to 1,2-dibronopropion-
aldehyde, giving a dark heavy sirup. Both acid and base hydrolysis of thee
material, with subsequent purifiication, gave a dark heavy oil which formed

a dark resinous substance within one hour at room temperature. Experiment-Z-a

(54)

employed the Zelinsky and Stadnikoff modification of the original Strecker
synthesis to non-brominated acrolein, freshly distilled. A reddish-brown
resinous material was obtained at the stage where the aninocyanohydrin
should have been obtained. Experiment-z-b was a repeat of experinent~2-a,
except that a much lower temperature was used, The lower temperature of
reaction did not prevent the polymerization of the product. in experiment-5
vinylglycolic nitrile was prepared and characterized by the method of Glatter-
fold and Econ (36) and the corresponding alpha-chlorocyanohydrin was prepared
by the method of Rarband (32). Attempts were made to condense this chloro-
derivative of vinylglycolic nitrile with potassium phthalimide, which was
prepared by the method of Hale and Britten (58). The temperature necessary
to promote a reasonable rate of reaction was sufficient to polymerize the
chloro-derivative, giving rise to a solid dark mass. he reaction would

not go using high-boiling ligroin or benzene as solvents.

The method of Galat (#5) was utilized in experiment-A to prepare fornyl-
amino-diethylaalonate, from which the sodio-derivative was prepared, and
reacted with 2-bromo-l-ethanol. No unsaturated compound was formed when
the dehydration of the product was attempted using P205 and bensdne. An
aldol condensation reaction was attempted in experiment-5 between fornyl-
amino-diethylnalonate and acetaldehyde, using pyridine as a catalyst. Ana-
lytical results for carbon, hydrogen, and nitrogen determinations indicated
that the coupound was almost totally unreacted ester. however, an unsaturated
compound, alleged formylamino-vinylmalonic ester, was obtained by refluxing

an ethyl prepionate solution of the compound over P205. The quantity of

(55)

unsaturated material was insufficient to characterize. Thus, it can not be
concluded that the positive Bayer's test was only due to the alleged compound.
Ekperiment-é-a involves the preparation of ethyl monobroaonalonate by a method
submitted by Palmer and hchherter (49), potassium phthalinide by the method

of Hale and Britten (#8), and phthalimide diethylmalonate by Gabriel's (50)
method, fron.ehich the sodio-derivativc was prepared. ihe condensation of

the sodio-derivative and 1.2-dibromoethane would not go using benzene as a
solvent, but in experiment-é-b the condensation was carried out using high~
boiling ligroin as a solvent, giving rise to a heavy reddish oil. After

the oil failed to give a crystalline product it was fractionated at 1-5 mm.

of mercury, leaving a black tarry residue. Fraction I was mostly high-boiling
ligroin, while 11 and III were the same, as shown by m.p's. after crystallie
aation from benzene and ligroin. The crystalline product nelted at 7} (un-
corrected).

Anal. found: c, 59.40; a. 5.c1; a. 5.31; 'xo Bromine'
59.h5 4.96 5.59 'uo ash'

calcd. for 017HISO€NBrs
0. 49.50: H. 4-40: N. 5.59: Br. 19.59
It is quite Ovident that the 'bronine-containing oil‘I undergoes decom-
position vhen distilled at 1-5 mm. of mercury to yield a bromine-free compound.

The decomposition is believed to have proceeded in the following order.
COEt

coat
0 ( - 023531' ) rig-one
Br-CH .0” H _“ “ r :: k
2 2 6 4 \”<::::96“
ccoat ' 4
(b)

(t) o=c----o

 

(56)

(a) (b)
:1 0- 19-51 71' C-- 59-55
8- Moo H-- has
Bru- 19e50

00H >5fla
‘ H “CH
...—...> 2>2 — x;- rig-CH2 H-T-o
("A ....o“...

 

czc-mo
(d)
(c)
N: 0" 56.70 57: 0"" 61.80
H“ 3.50 H“ 3090
11- 5.08 5—- 6.00

One may conclude that, on the basis of the per cent nitrogen found,
the crystalline product is a mixture of compounds (c) and (d).

The condensation of sodio-phthalimide diethylnalonate and 1,2-dibromo-
ethane was carried out in eXperiment-é-c in the absence of high~boiling
ligroin, allowing one of the reactants to act as a solvent. The product
was a heavy reddish-brown oil, containing both nitrOgen and bromine. The
oil, alleged phthalimide(beta-bromoethyl}-diethylnalonate, was subjected
to the proper conditions for dehydrohaIOgenation using potassium amide in
liquid ammonia. An unsaturated compound was obtained which added bromine
and decolorized KLnOh solution. The final product, alleged alpha-amino-
betaebutenoic acid, added bromine, decolorized XEnOA solution, and gave a
positive ninhydrin test. No attempts were made to remove the material from
the solution (5 so.) at this point. The following results were obtained

when this material was chromatOgraphed along with homoserine and threonine

(37)

using 6' X 22' stripe of hhatman # 1 paper in n-BuGH-formic acid-mater
(77'13-15 per cent respectively) solvent system.
(a) Unknown (alleged vinylglyoine)

(b) Hemoeerine

 

(c) Homoeerine / Threonine

(d) unknown / Homoserine f Threonine

r' ".‘.
I

Jr! (,7:

o ’ a- ‘ I-..

13; . 1+: .c .

.1 s v \ - a

‘:"l \l'. .
~9~ -O- - 9-. 0

 

 

Application (a) gave rise to two spots, 1 and 2. Snot 2 has a Rf

A

value of 0.h2, which corresponds somewhat to the Rf value of 0.46 listed

for glycine in n-BuCH-formic acid-water (600-50-50-reepectively) solvent

(58)

system (51), while spot 1 does not correspond to any value listed for amino
acids. Iomoserine and threonine were not resolved under the conditions
employed here, as shown by application (0), giving only spot h which sorrow
sponds to spot 5 from application (b). Application (d) gave rise to spots
5, 6, and 7. Spot 7 corresponds to spot 2 or glycine, while spot 6 corse-
sponds to spots 5 and #, homoeerine and threonine. Spot 5 is relatively
close to spot 1 in Rf value, that is, it may be concluded from this particular
situation that spots 1 and 5 are due to the sane substance. Spots 2 and 7
or glycine would be expected if traces of phthalimide diethylmalonate were
present in the sample of alleged phthalimide-vinylmalonic amide undergoing
hydrolysis. No attempts were made to slut spots 1 and 5, or even better,-
to apply larger quantities of the unknown to a heavier paper and elute for
characterization purposes. .However, attempts were made to crystallize the
material (4.5 cc.) from alcohol and water, which resulted in a total non-
recovery of any material which added bromine or decolorized lino“ solution.
The replacement of the fornylamincmalonic ester function by the phthalr
imide function to obtain the beta-hydroxyethyl-dsrivative (primary alcohol)
in experiment-7 and the alpha-hydroxyethyl-derivative (secondary alcohol)
in sxperiment~8 gave little or no achievements, under the conditions employed,

in so far as the introduction of a vinyl group into a malonic ester derivative.

(59)

SUPRAR!

The following is a summary based on the conditions specified in the
procedure employed for each reaction.
1. Various modifications of the original Strecker synthesis failed to yield
a stable dibromo-alpha-aminocyanohydrin, starting with 1,2-dibrosopr0pionalde-
hyde. A.white crystalline compound, containing bromine and approximately
three times the calculated per cent of nitrOgen, was obtained by carrying
the synthesis through without isolating he alpha-aninocyanohydrin.
2. Resinous materials were obtained on attempts to prepare the alpha-amino-
cyanohydrin derivative from acrolain.
5. Unsuccessful attenpts were made in condensing potassium phthalimide
and alpha-chloro-vinylacetonitrile.
h. ihs preparation of forsylaminonslonic ester and the corresponding sodio-
derivative was conducted. Treatment of the sodio-derivative with 2-bromo-ln

ethanol and subsequent refluxing over POO failed to give a vinyl-derivative

5
of nalonic ester. However, an aldol condensation reaction involving acet-
aldehyde, forsylasinomelonic ester, and pyridine as a catalyst, with cube
sequent refluxing in benzene over P205 gave a very small quantity of a sub-
stance which added bromine. Further investigations along this line wsse
abandoned since it was Iebeled as being impractical on the basis of the yield
and the rate of the reaction.

5. The condensation of sodio-phthalimide diethylmalonate with 1,2-dibrono-

ethane gave an oil, alleged phthalimide(beta-bromoethy1)-diethylmalonate,

which decomposed rapidly when distilled at 1-5 mm. of mercury giving a

(‘0)

bromine-free compound. when the oil was carried through a series of reactions,
after dehydrohaIOgenation with potassium amide in liquid ammonia, to the stage
where alpha-amino—beta-butenoic acid should have been present, two spots were
obtained when the material was subjected to paper chromatography. One spot
corresponded to glycine, while the other spot did not correspond to any Wat-vino
acid.
6L The replacement of the foruylamino function by the phthalimide function
in the corresponding derivative of diethylmalonate failed to aid in the
introduction of a vinyl group when the primary and secondary alcohol functions
were introduced and subsequently subjected to refluxing in benzene over P205.
7. All experiments which involved acrolein as the starting material gave
resinous materials regardless of the conditions used. The stability of
acrolein is not great enough to be subjected to the conditions necessary for
the reactions to go. lhue, it is felt that alpha-amincebetasbutenoio acid
(vinylglyoine) can not be obtained by the pathways proposed using acrolein
as the starting material.

All attempts made to introduce a vinyl group on formylaninonalonio
ester and phthalimide diethylmalonate failed. Hewever, the results obtained
in this area of reactions were sufficiently favorable to establish that the
vinyl derivative, of the above mentioned structures, is probably a practical
synthesis under a set of conditions different from those specified in this

document.

1.

2.

5.

k.
5.

7.
8.
9.
10.
11.

12.

13.
1h.

15.
16.
17.
13.
19.

(61)

3 I .31..IC:G-fiAf IT

Horewitz. }.H.. J. 3101. Ohem.. 21;, 255 (19h7).

Teas, H.J.. Rcrowitz, 3.3.. and Fling, K., J. 3101. Chem., 113, (51 (1943).
Buss, 3.3.. Fh.D. Dissoration, Stanford University (1944); Teas, H.J..
Horowitz. R.H.. and Fling. 5.. J. 3101. Chem.. £129 (51 (1943).

Fling, F., and Horowitz, E.H.. J. 3101. Chen.. 1293 277 (1951).

Tens, H.J., J. 3act.. 22, 95-135 (1956).

Cohen. 6.5., and attach, m.L.. Compt. rend.. 3:5; lace-h (1953).
Hirsch, N.L.. and Cohen, G.N.. Compt. rend.. 22g, 2333-40 (1933).
Umberfer, m.a.. J. 8ncter101.. 5:, 225-9 (1955).

Eelluva, A.E.. Arch. Biochem. Biaphys.. £2, #45-46 (1955).

Kalan. 8.3., and Coithzml. J.. J. Bactor101., {2, 293-5 (195#).

Cohen. G.fi., Hiraoh, k.Lw. Eioaendanger, 5.3.. and Kiaman, 8..

CO" to rend” 223' 17464 (19%).

":5

Cohen. c.n., Birlch. M.L., wiesendanger. 8.3.. and Kiaman. 3..
Conrt. rond.. 222, 15h2-4 (1954).

Black, 8.. and wright. 0.3.. J. An. Chem. 500., 15, 5766 (1953).
Entanaho, Y.. Fonichi, 8.. and Shimura. K.. J. Biochem. (Japan).
32) 557‘45 (1955)-

yolwod, A.J.. and freon. 3., J. Gen. m1crobiol., 3, 561-7 (1950).
Lion, 0.6.. and Grecnberg, D.M.. J. 3101. Chem.. £22, 657 (1952).
Lien. 0.6..and Grecnbcrg, D.E.. J. 3101. Chas.. £22, 5&7-71 (1953).
301901;. J.L.. Arch. Biochenu, 2g; 25A (1952).

Lenti. 0.. und Grillo. fl.A., Attt accd. Sci. Karine, class. sci.

f1... ”.31.. O “to. {5.5, 26C‘57 (1951“1952).

55-
56.
37-

35.

’40.

(62)

Reyna. F., and fialter, %.. finturwiasonachafton, 22, 5CJ (1952).
Kielrnd, 7.. and hirtk. L.. Cher. Ber.. £2, #63-73 (19&9).

Armstrong, F.5., and Sinkley, F.. J. 3101. Chem., 122, 1359-(5 (1§49).
arcetrong, r.r., ard Binkley, F.. J. Biol. Chem., lZfl, 939-52 (19#3).
Fromawrot. 0.. and Clauser, 8.. BiocPim. at Bioyhya. écta, :, 4?2-26
(1949).

Fairley, J.L.. J. 31.1. Chem., ;_3, 347-51 (1?5h).

ninetead, R.§., Koblo. 3.6.. and Boorwan, £.J.. J. Chem. Soc.

2222; 557-61.

HOuben. J.. Chem..3¢r., iii 2397 (ISCB).

Fichter. l".. and Sonneborn. 1"" Chem. Bar” :2. 95-3 (15%).

Bruylnnt. P.. Bull. Soc. Chim. *1 223 (19?2).

Hhitmore, 3., Crgnnic Chemistry (tea), P. 252. 2 nd. edition.

Rnnband, 3.. 3u11.. Soc. Chim., (5) 1, 1236—52 (1934).

Rarband, 3.. Bull. Soc. Chim.. (5) A, 1§l7¥41 (1934).

Barker, A.L., and Skinner. 0.5.. J. Au. Chem. 800.. fig} #67-14 (19?4).
chinnky, 3.. and at.dn1korr.wc., Chem. 3ct., :2, 1722 (1906).
iolinsky, s.. and atadnikofr. G., Chem. Ber.. 31, 2c61 (1995).
Glattefeld, J.W.E.. and fioen, H.B.. J. Am. Chem. Soc., 21, 1‘06 (1935).
Voorhrea, V., fh.D. Dissertation, University of hisconain (19?h)3

J. Am. Chem. Soc., fig, llah-27 (1925).

Voorhoen, 7.. and Skinner, 6.5.. J. Am. Chem. Soc., 31, 1124-27 (1925).
Goya, A.C.. and lcElvain, 8.k.. J. Am. Chem. 800.. 2g, 5511*19 (1952).
Sorenean, S.P.L.. and Andersen, A.C.. Zoitschr. f. thsik. Chauie, 3d..

2g; 265-66 (1923).

((-5)

Soreneen, 8.P.L.. and Andersen, 1.6.. Zeitschr. f. ihysik. Cheaie, 3d..
2g} 273-75 (1933 .

Router, 0.3., 31911, 1.5.. Bright. ..E., unfl Renflew, t.3., J. Am.
Chem. Soc.. 552 (1947).

fiedcnann, 0.3.. and Dunn. 1.5.. J. 3101. Chem., 122, 5&1 (1959).
Snyder. n.n., and ssith. c.w., J. Am. Chem. Soc.. £1} 33c (lskh).
Calat, 1., J. An. £60.. $2, $55 (19b7)o

Conrad, 1., and Schulte, 1., Chen. 3.:., 5;, 735 (lgcg).

attacker. 1.. Ann., 12, 27 (135C); Block, R.J., Chem. Rev., :2,

523 (19fif).

3.1., r.J., and Britten, 5.0., J. Am. Chen. Soc., £3, an) (1919).
Palmer, 0.5., and [chhartsr, F.K.. Crg Synth., Collective V01. 1.

r. 2&9.

Gabriel, 5., and Kroseberg, K., Chem. Ber.. 2‘, h26¥8 (1358).

Block, R.J., Durrum, E.L., Zweig, 6.. A manual of paper chromatography

and paper electrOphoresin.

magma: LIBRARY

Date Due

Demco-293

 

 

 

 

 

 

 

 

4.116318 ... CHEMISTRY LIBRARY
c.2 0rd, Leoplas

An investigation of chemical
methods fior the synthesis of alnha
amino—beta-butenoic acid (vinylglycin

 

H

 

WITH @1117) [i (iujffl'fljtmfgfimfl‘s