CHLORINE DERIVATIVES OP M-CRESOL

A Thesis

Submitted to the Faculty of the
Michigan State College of Agriculture and Applied Science
in partial fulfillment of the requirements for

the Degree of

Doctor of Philosophy

by

Philip Stanley Chen

19 33

ProQuest Number: 10008481

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A cknowledgment

The author wishes to express
his thanks to Dr, R. C. Huston for his
kindly guidance and timely ercouragemnet
in accomplishing this work.

94610

Table of Contents

Page
Introduction

1-8

Experimental
Mono Chloro-m-cresols
2-Chloro-m-cresol

9-11

4-Chloro-m-cresol

11

6-Chloro-m-cresol

12-13

Mono chloro-m-cresols by direct chlorination 13Dichloro-m-cresols
4.6-Eichloro-m-cresol

14-15

2.6-Pichloro-m-cresol

15-16

2 *4-Dichloro-m-cresol

16

Dichloro-m-cresols by direct chlorination 16-17
Chlorination of mono chloro-m-cresols
Chlorination of dicbloro-m-cresols
Esterification
Summary

17-18
18
18-20
20

Introduction

This study had as its objective a survey of those
chloro derivatives of m-cresol in which the chlorine atoms
are ortho or para to the hydroxyl group. Information
concerning these compounds is meager and often conflicting.
MONO CHLORQ-WUCRESOLS
Gibson^- describes 2- chloro-m- cresol, as prepared
from its methyl ether, as massive ill-defined transparent
crystals melting at 55-56°. When prepared by the following
sequences it melted at 49-50°,
clusters of tetragons.

its crystalline form being

^
OH

HOOgS,

sooo:

V /IGH
s o g o :

The preparation and properties of 4-chloro-m-cresol
have been described by several investigators. A brief
discussion of their work is given below:
The earliest work done on the chlorination of
m — cresol was by Bied.ermanns , who by chlorinating m-ere sol

(1) Gibson, J. G h e m . Soc., 1926, 1424-8.
(2) Biedermann, Her., 6 , 325 (1873).

2

in the state of vapor obtained 4-chloro-m-cresol melting
at 56°.

- (P
The preparation of 4-chloro-m-cresol by chlorinat­

ing an exceedingly cold solution of m-eresol in glacial
©cetic acid was described in a patent taken out by Kalle
and Company^. The melting point of 66° given for 4-chloro
m-creol has not been supported by experiment data.
The 4- chloro-m-cresol was later prepared by Peratoner
and Condorelli^ from m-cresol by the action of sulfuryl
chloride. They gave the melting point as 52-53°.
Chlorination of a technical mixture of m- and pcresols was tried by Raschig5 , who found that the action
of sulfuryl chloride or chlorine on this mixture of
cresols is selective.

If only sufficient chlorine is

introduced to react with the m-cresol this alone is
attacked, and on subsequent distillation the p-cresol
will pass over at 200° followed by pure 4-chloro-m-cresol•
The 4 - chloro-m-cresol was also obtained by Liebrecht®
from the mixed cresols by a modified method. The 4-chlorom-cresol is separated from the isomers and the simultaneously
produced o-chloro-p-cresol by sulfonating the chlorinated
mixed cresols. While 4 - chloro-m-cresol is converted into
the sulfonic acid,

o-chioro-p-cresol remains unchanged

and can therefore be readily separated.

(3) Kalle and Co., D. R. P. 90847; 93694.
(4) Peratoner and Condorelli, Cfazz. chim.
28 I, 213 (1898).
(5) Raschig, D. R. P. 232071.
(6 ) Liebrecht, D. R, P. 233118.

ital.,

3

Gibson^obta.ined a mixture of three mono chloro-mcresols by treating m-cresol in carbon tetrachloride with
a saturated solution of chlorine in the same solvent.
4 - chloro-m-cresol distilled over at 231-.233° while the
2- and the 6- isomers distilled over at 196-197°. The
benzoyl and p-toluene sulfonyl esters of 4-chloro-mcresol melted at 86° and 98° respectively.
Chlorination of m-cresol with a mixture of both
sulfuryl chloride and chlorine was described in a recent
rt
patent taken out by Laschinger'• M-cresol is treated with
a mixture containing sulfur! chloride and a substantial
amount of uncombined chlorine,

the total amount of

chlorine being substantially no greater tha.n the amount
required to convert the m-cresol into 4-chloro-m-cresol.
The following sequence of r e a c t i o n s ^ w e

employed

gave 4-chloro-m-cresol as clusters of very fine needles
melting at 55.5°.

Tb.e first m e n t !on of 6- chloro-m-cresol v:as me.de
by Raschig®, who obtained It along with the 4-chloro— in­
ches ol in the chlorination of m-cresol by the action of
sulfuryl chloride. He was unable to isolate it in the

(7) Laschinger,

U. .
8 . 1847 566,

4
solid form.and describes it as a colorless liquid boiling
at 197° and with a camphor-like odor.
A s has b een mentioned before,

6- chloro-m-cresol

was one of the three mono chloro-m-cresols formed when

Tri­

cresol. ia carbon tetrachloride was treated with a
saturated solution of chlorine in the same solvent as
described by Gibson . The benzoyl ester prepared from
it melted at 31° (from alcohol) and 4-0° (from petroleum
ether), and the p-toluene sulfonyl ester at 98°.
The preparation of 6- chloro-m-cresol by diazotization has been described by Hodgson and Moore® who
prepared it from 4-chloro-m-nitrotoluene by first
reducing with tin and hydrochloric acid a n d then
s^lbjecting to diazotization and hydrolysis* The 6chloro-m-cresol melted at 45°•
A method for preparing 6- c&loro-m-eresol from
o-dichloro benzene was described by Kraay^. It was
prepared by substituting a methyl group in the para
position of 6-dichloro benzene and then treating the
resulting product with sodium methozide in methyl
alcohol. The formation of 6- chloro-m-cresol was also
checked by preparing it from S-amir.o-^ch loro toluene.
The preparation of 6- chloro-m-cresol in. the
present work was accomplished by the following
sequences* It melted at 46°.

(8 ) Hodgson and Moore, J. Chem. Soc*, 1996, 2036-40.
(9) Kraay,
Rec, trav. chim*, 49, 1082-92 (1930).

5

1
JTO

Cl
►NH

Cl
,OH

CH

CH 3

iOH
■>

Chlorination of m-cresol

in chloroform at 0°

gave a mixture of the three isomers. These were separated
by fractional distillation and seeding. As seen from above,
ehloroform has never been used as a solvent in the
chlorination of m-cresol,
DICHLORO-M-CRSSOLS
The properties of 4,6- dichloro-m-cresol which
we prepared by four different methods did not agree with
those described in the literature, v, Walther and Zipper

10

who prepared it by passing a calculated. amount of chlorine
into a warm solution of 4-chloro-m-cresol in aqueous
sodium hydrogen carbonate,

gave it a melting point of

45-46°; while Tanaka and Morikawa-*--^, who obtained it by

(10) V, Walther and Zipper, J, prakt, chem „,
(2) 91, 374 (1864).
(11) Tanaka and Morikawa, J. Chem. Soc. Japan.
51, 275-7 (1930).

,

chlorinating m-cresol in harbor tetrachloride in an
ice bath, reported the melting point as 58°, We obtained
a constant melting point of 71,5-72.5° and a boiling
point of 235-236°• The four methods we used for the
preparation of 4,6-dichloro-m-cresol are represented
by the following sequences:

OH

01

N ^ H3
Cl

OH

OH

01
NO

NH

'CH
Cl
The preparation of 2 ,4-dichlcro-m-cresol has
!also, been reported, Tanaka and. Morikawa-^ obtained it by
chlorinating m-cresol

in carbon tetrachloride at room

temperature and gave its melting point as 44°, Datta and
Mitter^,

who prepared it by replacing the corresponding

sulfonic acid groups in the m-cresol with chlorine,

(1 2 ) Datta and Mitter,

This Journal,

gave

41, 2033 (191

7

it a melting point of 45° and state that their compound
is identical with the dichloro-m-cresol prepared "by Claus
and Schweitzer-*'3 who gave its melting point as 46°®
-jJ
A s was pointed out by Crowther and McCombie-*-^, and also
supported by the work of Raiford-*-3, Claus and Schweitzer* s
dicholoro compound was most probably the 2,4,6- trichlorom-cresol of the same melting point. The same might be said
of the 2 ,4-dichloro-m-cresol prepared by Tanaka and Datts
and their coworkers•^The 2,4-dichloro-m-cresol we prepared
by careful chlorination of a cold chloroform solution
of 2 - chloro-m-cresol or 4 - chloro-m-cresol boiled at
234° and melted at 58°®
f f ,vy
Attention might also be called to the fact that in
Datta and Mitter*s work of converting the disulfonic acid
into the corresx^onding flichloro compound,

chlorine was

passed in to "saturation" and the resulting product not
analyzed. Furthermore,

they state that 2,4-dichloro-m-

cresol was also the sole product of chi or ins. ting m-cresolp-sulfonic acid. It is hard to see why the second atom
of chlorine should enter the 2-position more readily
than the 6-position^ ^while the reverse is more probable.
A

comparison of melting points might indicate that

the 4 ,6-dichloro-m-cresol prepared by v, Ralther and
Zipper was also the trichloro-m-cresol, while on the
other hand the 4,6^»dichloro-m-cresol prepared by Tanaka.

(13) Glaus and Schweitzer, Ber,, 19, 930 (1886),
(14) Crowther and McCombie, J. Chem. Soc,,
103, 545 (1913).
(15) Raiford, Am. Ghem. J., 46, 424- (191].).

8
and Morikawa might be the 2 ,4-dichloro-m-cresol*
The literature gives no description of* 2,61 *^
d i c h l o r o - m - c r e s p l . A s prepared by the following sequences
it boiled at 240.5-242.5° and crystallised from petroleum
ether in prisms melting at 27°.

Chlorination of a cold chloroform solution of mcresol with two mols of chlorine gave a mixture of the
three dichloro-m-cresols. From this, 4,6-dichloro-mcresol and 2 ,4-diehloro-m-cresol were separated by careful
fractionation,

cooling, and seeding. The fraction boiling

at 240.5-242.5° analyzed for two atoms of chlorine and
gave 2 ,4,6- trichloro-m-eresol when further chlorinated.
We believe it consisted of 2,6-dichloro-m- cresol wliich
failted to crystallize because of the presence of small
amounts of its isomers.
Each dichloro-m-cresol gave upon further chlorina­
tion in cold chloroform the same 2 ,4,6- trichloro-m-cresol
(fine prisms, m.p. 46°). This was also the only product
formed when m-cresol was chlorine.ted in chloroform with
three mols of Bhlorine.

9

Experimental

The chloro-m-cresols described "below were
purified by recrystallization from petroleum ether
and their esters from ethyl alcohol. All cases of
identity were established by the method of mixed
melting points.
MONO CHLORO-M-CRESOLS
2-Chloro-M-Cresol
From 2-nitro-m-cresol: 2-Nitro-m-cresol was
prepared from m-cresol lay nitration in fuming sulfuric
acid in the cold and reduced to the corresponding amino
compound according to Hodgson and Beard

1A

. Forty-four

grams of 2-amino-m-cresol was treated with hydrochloric
acid, diazotized, and converted into the corresponding
chlorine compound by the Sandmeyer method as modified
* bjr Marvel and McAlvain for the preparation of o- and pchloro t o l u e n e ^ * The 2-chloro-m-cresol thus obtained
boiled at 198-199° and melted at 49-50°. Yield 32 g.
Anal. Calcd. for C7H7 QC1: Cl, 24.91, Found:

Cl, 24.77.

By chlorination in fuming gulfuric a c i d : The
method here used is similar to the one given above for
the preparation of 2-nitro-m-cresol,

except that in the

place of nitric aicd, one mol equivalent of c h l o r i n e ^

(16) Hodgson and Beard, J. Chem. Soc,, 127, 498 (1925).
(17) "Organic Syntheses’1, Wiley and Sons, Vol. Ill, 33.
(18) Houben, "Die Methoden der organischen Chemie",
Leipzig, 1924, Vol. Ill, 799.
•' *7 7

v

10

was passed in the filming sulfuric acid solution. Chlorine
was not teadily a b s o r b e d . When the resulting oil separated
from the distillate was fractionated five times, it gave
a small fraction boiling at 198-199° and a larger fraction
at 199-205° which consisted mostly of the unreacted
m-cresol. The 198-199° fraction was set in the ice box
and seeded with 2- chloro-m-cresol prepared from 2-nitrom-cresol. The crystals that separated out from the oil
were suction filtered and re crystallized from petroleum
ether* The purified product melted at 49-50°.
By Chlorination of the sodium disulfonate:

One

mol of m-cresol was heated for three hours with 1.5 mols
of concentrated sulfuric acid. The mixture was cooled
and made alkai.ine with 5 mols of sodium hydroxide in
500 cc. of water.

It was then chlorinated with two mols

of chlorine generated from the calculated amount of
potassium permanganate and concentrated hydrochloric acid-**®,
while the solution was stirred and its temperature main­
tained at 40-50°* The alkaline reaction mixture was
distilled, with steam,

the flask being set In an oil bath

kepi at 150°. When no more oil distilled over,

steam

distillation was stopped and the content in the flask
evaporated to a thick paste. It was allowed to cool and
then acidified with 600 cc. of concentrated sulfuric
acid. Steam was again passed in and the oil bath, raised
to 200-210°, The oil was separated from the distillate
and fractions.ted. It gave after seven distillations a

11

15 g. fraction boiling at 195-200° and a larger fraction
(22 g.) at 235-245° which consisted of 2,6-dichloro-mcresol to be described later. The 195-200° fraction was
set in the ice box and seeded with 2- chloro-m-cresol. The
crystals that separated out were filtered at the pump and
purified, rru p* 49-50°.
4- Chloro-M-Cresol
From o-chlorotoluene:

0-chlorotoluene prepared

according to Marvel and McA. lvain*s method

17

was nitrated

according to Goldschmidt and H o n i g ^ , The resulting nitro
compound was reduced with tin-and hydrochloric acid. After
heating for haltff an hour to complete the reduction,

the

mixture was cooled, made alkaline with dodium hydroxide,
and steam distilled. The amine which solidified in the
distillate was recrystallized from ligroin, m. p. 83.5o 2 G .
Eleven grams of the 3-amino-6- chlorotluene was
treated with hydrochloric acid and diazotized in the
usual manner. The diazotized solution was heated on a steam
bath for half an hour during which time a dark oil
separated on top of the liquid. After steam distillation,
the distillate was salted out and extracted with ether.
Five and one half grams of 4-chloro-m-cresol distilled
over at 228-233°. Upon purification 4t came down in
clusters of fine needles melting at 55.5°.
Anal, Galcd. for CyH^OCl: Cl, 24,91. Found: Cl,

24.74.

(19) Boldsohmidt end Honig, Ber., 19, 2440 (1886).
(20) Bamberger, Ber«, 35, 3701 (1902).

12
6-Chloro-M-Cres ol
From p-toluidine:
nitrated,

The p-toluidine was acylated,

and hydrolyzed according to the method of

G a t t e r m a n n ^ • The hydrochloride was diazotized and poured
into a cold solution of cuprous chloride prepared by
Marvel and McAlvain s method
hour,

. A f t e r stirring for hne

the mixture was steam distilled. The distillate

was extracted with ether. The 3-nit.ro-4-chlorotoluene
oPP
distilled over at 258^262'
* When reduced with tin and
90
hydrochloric acid it gave the amine boiling at 228-232°~ ,
The diazotization and hydrolysis of J3-arnino-4chlorotoluene was accomplished under the same conditions
used in the preparation of 4- cbloro-m-cresol from 3-smino~
6- chlorotoluene* The 6- chloro-m-cresol came down in
rhombohedrons melting at 46°•
Anal; Calcd, for C^H^OCl: Cl, 24.91, Found: Cl, 24,69*
From -p-chlorotoluene:

The p - c h l o r o t o l u e n e ^ was

nitrated according to the method of Goldschmidt and
Honig-*-^ and the isomeric nitro chloroto3.uen.es were
separated by repeated distillation and filtration. The
liquid 3-nitro-4 - chlorotoluene was reduced, diazotized,
and hydrolyzed as

in the preseeding experiment. The

6- chloro-m-cresol melted sharply at 46° and was checked
by ester formation.

(21) Gattermann, Per,, 18, 1483 (1885),
(22) Gattermann and Falser, Per,, 18, 2600 (1885),

13
From 6- nltro-m-cresol:

Thirty one grams of

6- nitro-m-cresol prepared by Staedal and Kobb*s method

p rz

was reduced with stannous chloride according to the method
given by R a i f o r d 2 4 . The hydrochloride was filtered and
recrystallized to free from the tin. 6-Chloro-m-cresol was
prepared from it bjr the Sandmeyer method as described above.
10 g. were obtained, boiling at 195-200° and melting at 46°.
Mono Chloro-M-Cresols by Direct Chlorination
One mol of m-cresol chlorinated in 400 cc. of
chloroform at 0° with one mol of chlorine18 gave after
six distillations 33 g. boiling at 196-190°; 20 g. at
199-230°; and 70 g. at 230-238°. The 199-230° fraction
consists mostly of the unreacted m-cresol. The 230-238°
fraction gave upon purification 32 g. of 4-chloro-m-cresol
in fine needles, m. p. 55.5°.
The 196-199° fraction gave upon further distillation
18.5 g. boiling at 197-198°. When cooled to - 10° and seeded
with 6- chloro-m-cresol prepared from p-chlorotoluene, it
partially solidified. The crystals were filtered at once
by suction. The purified product melted at 46°.
The oil that remained after the complete removal
of 6- chloro-m-cresol was again chilled and seeded with
2- chloro-m-cresol prepared from 2-nitro-m-cresol. The
crystals fchich separated out were filtered by suction.

(23) Staedal and Kobb, Ann., 259, 210-211 (1890).
(24) Raiford, Am. Chem. J., 46, 419 (1911).

14
Thejr recrystallized in clusters of tetragonal crystals,

m. ,p. 49-50°.
D ICHROR 0-M-CRES ols
4,6~Dichloro-M-Cresol
From 6-nitro-m-cresol:
m-cresol

Chlorination of 6-nitro-

in cold chloroform or acetic acid solution with

two mols of chlorine gave only the 4-chloro-6-nitro-mcresol (m. p. 131-133°)8 ^. This was reduced with stannous
chloride and hydrochloric acid2 4 . The resulting hydro­
chloride was diazotized and. treated with a cold solution
of cuprous chloridelT. Upon steam distillation,

4,6-

dichloro-m-cresol separated out from the distillate as
an oil. When separated and purified,

it melted at 71.5-

72.5°. Its p-toluene sulfonate melted at 104-105°.
Anal. Calcd. for G^H^OClg:

Cl, 40.11. Found:

Cl, 40.39.

From 4,6-dlnitro-m-cresol:

The 4,6~dinitro-m-cresol
p 'Z
was obtained from 4-nitro-m-cresol"^ by nitration in
acetic acid solution according to Gibbs and Robertson
Jfifter standing overnight,

20

•

the reaction mixture was poured

into water and the oil that separated out was purified,
by distillation under vacuum. The product was separated
from unchanged 4-nitro-m-cresol by fractional crystalliza­
tion from benzene. Further re crystallization from1
, dilute

(25) Kenner, Tod, and Witham, J. Chem. Soc.,
127, 2349 (1925),- v. Walther and Zipper,
J. prakt. chem., (2) 91, 411 (1864).
(26) Gibbs and Robertson, J. Chem. Soc.,
105, 1889 (1914).

15
acetic acid gave a product melting at 71

J . Aft er reduc-

tion with stannous chloride and hydrochloric acid

P4-

, both

amino groups were diazotized and replaced with chlorine
by the Sandmeyer method-*-^. This method ga\re a smaller
yield of 4,6-dichloro-m-cresol than the preceeding method.
2 ,6-Dichioro-M-Cresol
From 4-nltro-m-cresol•

The 4-nitro-m-cresol
P 'Z

prepared b y the method of Staedal and Kobb

was

chlorine.ted with two mols of chlorine in glacial acetic
acid# The crystals that separated out were filtered off
and the filtrate poured, into a large quantity of water
from which another cron of crystals was obtained#
Recrystallized *from benzene both crops melted at 143°
po
with decomposition
. The 2,6-dichloro-4-nitro-m-cresol
was reduced with stannous chloride in the usual manner#
An:; attempt to liberate the amine from the hydrochloride
by means of ammonium carbonate was not successful#
Eight grams of the hydrochloride was diazotized
and the amino group replaced with hydrogen by means of
oq
an alkaline solution of stannous chloride
* The resulting
2 ,6-dichloro-m-cresol boiled at 240.5-242*5° and melted
at 27°. Yield 6 g.

(27) Will, Per,, 47, 712 (1914); Sane and Joshi,
J. Indian Chem. Soc#, -5, 299-301 (1928)#
(28) Raiford, This Journal, 36, 675 (1914). (J#A,g.S.)
(29) Houben, nDie faethoden der organIscheu Chemie ,
Leipzig, 1924, Vol. IV, 612.

16
Anal, Calcd, for* O ^ H ^ O C l ^ : Cl, 40.111, Pound:
SSL Chior i na t i on of the sodjurn su 1 fonate:

The

fraction boiling at 235-245° obtained in the preparation
of 2- chloro-m-cresol (page 1 0 ) was repeatedly fractionated.
Most of it came over at 240.5-242.5°, This was shown by
analysis,

ester formation, and chlorination to 2,4, 6-tri-

chloro-m-cresol to be identical with the 2 ,6-dichloro-mcresol prepared from 4-nitro-m-cresol.
2,4-Pichloro-M-Cresol
This compound as prepared by the chlorine.tion of
either 2- chloro-m-cresol or 4-chloro-m-cresol (see below)
came down in prismatic plates, melting at 58° and boiling
at 234°.
Anal. Calcd. for C^HgOClg: Cl, 40.11. Found: Cl, 40.20.
Pichloro-M-Cresols by Direct Chlorination
Chlorination of one mol of m-cresol in chloroform
solution at 0 ° with two mols of chlorine gave a mixture
which was separated By five distillations into the foil.owing
fr actions:
233-2 35°

20 g.

235-237°

82 g.

237-240°

27 g.

240-250°

13 g.

The crystals that separated

out from the first

three fractions upon standing were sBiliered at the pump
and purified. A yield of 6 0 ° g . of pure 4,6-dichloro-

17
m-cresol was obtained.
Crystals obtained from the mother liquor consisted
of a mixture of both the 4,6- and the 2,4-dichloro-m-cresols,
the separation of which could be effected by dissolving
in excess of petroleum ether and allowing to crystallize
slowly in the ice box. Under these conditions the less
soluble 2 ,4-dichloro-m-cresol was deposited around the
edge while the 4,6-

isomer was deposited at the bottom,

*

More of the 2 ,4-dichloro compound was separated
from the residual oil from which the crude 4,6-dichlorom-cresol had b ee n filtered, when this was allowed to
stand several days at - 10°. The total yield of 2 ,4-dichlorom-cresol was about 20 g.
After all possible 2,4— dichloro-m-cresol had. been
chilled ©ut,

the residual oil from the first three

fractions was combined with the fourth fraction, which
gave nocrystals,

and fractionated. A portion was

collected at 240.5-242.5° which corresponds to the
boiling point of 2, 6-dichloro-m-cresol. While we were
unable to isolate any of this compound (the 2 ,6-dichlorom-cresol melts at 27°) or to prepare a sharp melting
ester from it,

it did show two atoms of chlorine upon

analysis and was changed to 2 ,4,6- trichloro-m-cresol
when further chlorinated.
Chlorination of Mono Chioro-M-Oresols
Chlorination of each, of the mono chloro-m-cresols

18
in cold, chloroform with one mol of chl.orlne gave two
dichloro-m-cresols as follows:
2, 4-dichloro-m- cresol and
2-Chloro-m-cresol gave
2 .6-dichloro-m-cresol•
2,4-dichloro-m-cresol and
4-Chloro-m-cresol gave
4.6-dichloro-m-cresol•
4.6-dichloro-m-cresol and
6- Chloro-m-cresol gave
a ©mall amount of oil which
was doubtlees the 2 ,6- isomer.
The 2,4- and 4,6-dichloro-m-cresols were isolated
in the pure state. The 2,6- isomer was checked by formation
of the p-toluene sulfonic ester and further chlorination
to 2 ,4,6- trichloro-m-cresol»
Chlorination of the Dichloro-M-Cresols
A l l three dichloro-m-cresols gave almost theoretical
yield of 2,4 ,6-trichloro-m-cresol (m. p. 4 6 ° ) when
chlorine,ted in chloroform with one fiiol of chlorine. This
complete chlorination may be effected by chlorination
of m-cresol i&self in chloroform with three mols of
c hlorine»
Esterifi cation
The following esters of the various chloro-mcresols were prepared according to the method of Einhorn
and H o l l a n d ^ ,

(30) Einhorn and Holland, Anr.,

301, 95 (1898).

19
Table 1
Benpoyl Esters
Compound, Benzoyl
ester of m-cresol

Crys ta 11 ire form

2- chloro

clusters of prisms

4-chloro

needle-like plates

6- chloro

prisms

2 ,4-dichloro

fine plates

2 ,6- dichloro

clusters of small
prismatic plates
mats of very fine
needles
very fine prismatic
plates

4, 6-d.i chloro
2 ,4,6-trichloro

M • p . °C#

55-56

Chlorine
Calcd. Found
14.38

13.47

861

14.38

14.39

381

14.38

14.39

78-78.5 25.24

24.74

90.5 25.24

25,57

57.5 25.24

25.27

53

34.00

33.73

Table 2
Benzene Sulfunyl Esters
Compound, benzene
sulfonyl ester of
m-cresol

Crystalline form

F . p • On
c

2- chloro

prismatic plates

58-* 58 .5

4 - chloro

clusters of larye
needle-like plates
fine prisms

6- ch3.oro
2 ,4-dichloro
2 ,6- dichloro
4 ,6-dichloro
2,4,6-tri ohloro

fine needle-like
plates
thin lustrous plates

Chlorine
Calcd. Found
18.74

12.11

66

12,74

12.50

99

12.74

12.53

69.5

22.38

22.73

70

22.38

22 .82

22.38

22.01

30.28

30 .21

clusters of elongated 86
prisms
121
prismat&c plates

20

Table 3
P-toluene Sulfonyl Esters
Compound, p-toluene
sulfonylester of
m-cresol

Crystal.line form

2- chloro

fine lustrous prisms

96

12.13

11.75

4 - chloro

981

12.13

12.69

6- chloro

clusters of needle
like plates
prismatic plates

9.
3- 94!

12.13

11.92

2 ,4-dichloro

verv shinv plates

100- iei

21.43

21.72

2 ,6-dichloro

small prisms

92-92.5 21.43

21.21

4, 6-dichloro

very fine needles

104-105

21.43

20.69

2 ,4, 6- trichloro

nr isrr.a t.i c pla tes

92-93

29.12

29.24

P. n. °C

Chlorine
Calcd . Pound

*<

Summary
1 . Chlorination of m-cresol in chloroform with one
mol of chlorine gave rise to 2-, 4-, and 6- chloro-m-crosols.
2, Chlorination of m-cresol in chloroform with two
mols of chlorine gave rise to 2,4-, 2 ,6-, and 4,6-dichlorom - cr es ol s«
3 , The structures of the chloro-m-cresols were
proven by a number of methods.
4 . The benzoyl, benzene sulfonyl, and p-toluene
sulfonyl esters of all chloro-m-cresols were prepared.