THE CONDENSATION OF SOME OF THE DIPHENYL ALKYL
CARBINOLS WITH PHENOL IN THE PRESENCE OF
ANHYDROUS ALUMINUM CHLORIDE

fcy
Richard

Ives Jackson

A THESIS
Submitted to the Graduate School of Michigan
State College of Agriculture and Applied
Science in partial fulfillment of the
requirements for the degree of
DOCTOR OF PHILOSOPHY"

Department of Chemistry
1940

ACKNOWLEDGMENT
To Dr* R* G* Huston, tiio author wish©
to express his thanks for his invaluable
aid and advice in the accomplishment of
this work.

TABLE OF CONTENTS
page
I

Introduction

1

II

Historical

2

III Discussion
(1) Preparation of the Diphenyl Alkyl
Carbinols

5

(2) Condensation of the Diphenyl Alkyl
Carhinols and the Diphenyl Alkenes
with Phenol
(3) Preparation ofDerivatives

10
17

(4) Identification of Compounds and
Proofs of Struct\ire

20

(5) Interpretationof Results

25

IV

Experimental

32

V

Summary

39

VI

Bibliography

40

-1-

I

Introduct ion
In 1916, Huston and Friedeman (1) condensed benzyl

alcohol with benzene in the presence of anhydrous alum­
inum chloride. This work was followed, in 1924, by the
condensation of benzyl alcohol with phenol by Huston (2).
In 1927, Huston, Lewis and Grotemut (3) condensed
benzohydrol, methyl phenyl carbinol, and ethyl phenyl
carbinol with phenol.
Attempts to condense diphenyl ethyl carbinol, di1 T>V*o«Tr1

n - n v rW
t±
n/w
l
0r

n

a

1

w UkX V dbMW *
•|

onH

rl 1

1 a n
- n v n njp*
wl
W

w

binol with benzene were carried out in 1933 and 1934

—

by

Huston and Wilsey (4) and Huston and Hradel (5). No
condensation resulted, but the carbinols underwent de­
hydration.
The condensation of diphenyl methyl carbinol with
phenol in the presence of anhydrous aluminum chloride
was reported by Welsh and Drake (6 ) in 1938.
To investigate further the use of anhydrous alum­
inum chloride as a condensing agent, the author has con­
densed the following diphenyl alkyl carbinols with phen­
ol: diphenyl ethyl carbinol, diphenyl n-propyl carbinol,
diphenyl iso-propyl carbinol, diphenyl n-butyl carbinol,
diphenyl iso-butyl carbinol, diphenyl sec-butyl carbin­
ol, diphenyl tert-butyl carbinol, and diphenyl n-amyl
carbinol.

-2-

II

Historical
The condensation of alcohols with phenol has been

accomplished by the use of numerous condensing agents,
a few of which are anhydrous aluminum chloride, zinc
chloride, magnesium chloride, alkali bisulfites, sulfur­
ic acid, phosphoric acid, and perchloric acid.
The first condensation of alcohols with phenol was
reported by Liebmann (7) with the use of zinc chloride
as condensing agent. The first use of anhydrous aluminum
chloride as a condensing agent for alcohols and aromatic
compounds was in 1897 when Nef (8 ) mentioned the forma­
tion of diphenyl methane from benzyl alcohol and benzene.
Huston and Friedeman (1) repeated this work and report­
ed a 30$ yield of diphenyl methane. Huston and Friedeman (9) later condensed aromatic secondary alcohdls

and

mixed aliphatic-aromatic secondary alcohols with benzene,
and Huston (2) oondensed benzyl alcohol with phenol,
anisole, and phenetole.
In 1926, Huston and Sager (10) attempted to conden­
se the following primary alcohols with benzene: methyl,
ethyl, n-propyl, n-butyl, iso-butyl, iso-amyl, phenyl
ethyl, phenyl propyl, and allyl. With the exception of
allyl alcohol, which gave a 16$ yield of allyl benzene,
no condensation resulted. Allyl alcohol was condensed
with phenol by Huston and Newmann (11).
Triphenyl methane was the only product isolated

-3

from the attempted condensation of triphenyl carbinol
with benzene by Huston and Davis (12) in 1927.
In 1924, Huston and Goodemoot (13) condensed cyclobutyl, cyclo-pentyl, and cyclo-hexyl carbinols with ben­
zene. As expected, cyclo-butyl carbinol showed the
greatest reactivity.
Only dehydration of the carbinols resulted when
Huston and Wilsey (4) and Huston and Hradel (5) and
Huston and Macomber (14) attempted to condense diaryl
alkyl carbinols and dialkyl aryl carbinols with benzene.
Up to this time, the investigations in this field
had indicated that, if an alcohol is to be successfully
condensed with benzene or phenol in the presence of an­
hydrous aluminum chloride, its alpha carbon must be un­
saturated, that is, double bonded or a member of a ben­
zene ring or strained alicyclic ring.
The formation of cumene from iso-propyl alcohol
and benzene by Huston and Hsieh (15) in 1936 was the
first successful condensation involving a saturated
aliphatic alcohol. Huston, Hsieh, and Fox (15),(16)
later condensed the tertiary butyl, amyl, and hexyl al­
cohols with benzene and phenol. Subsequently, some of
the tertiary heptyl and octyl alcohols were condensed
with benzene and phenol by Huston and co-workers (17).
Results similar to those of Huston, Hsieh, and Fox
were obtained by Tzukervanik and co-workers (18) in

4-

their condensations of some of the simple secondary and
tertiary aliphatic alcohols with benzene and toluene.
In 1938, Welsh and Drake (6 ) reported the conden­
sation of diphenyl methyl carbinol with phenol. However,
none of the diphenyl alkyl carbinols used in this in­
vestigation have been condensed with phenol.

-5-

III

Discussion

(1) Preparation of the Diphenyl Alkyl Carbinols
Diphenyl ethyl carbinol has been prepared from eth­
yl magnesium iodide and benzophenone by Klages (19),
Hell and Bauer (SO), Sabatier and Murat (21), from di­
ethyl mercury, benzophenone and sodium by Schorigen (22),
from ethyl propionate and phenyl magnesium bromide by
Masson (23), and from propionyl chloride and phenyl mag­
nesium bromide by Gilman, Fothergill, and Parker (24).
Diphenyl n-propyl carbinol has been prepared from
ethyl butyrate and phenyl magnesium bromide by Masson
(23), Sabatier and Murat (21), Scraup and Freundlich (25),
and Schlenk and Bergmann (26). Klages and Heilmann (27)
claim to have prepared it from n-propyl magnesium
iodide and benzophenone. However, Scraup and Freundlich
(25) and Schlenk and Bergmann (28) claimed that his
product was benzohydrol resulting from the reduction of
the benzophenone by the Grignard reagent. Sabatier and
Murat (21) reported a very small yield of the carbinol
from n-propyl magnesium chloride and benzophenone; the
principal product was benzohydrol.
Diphenyl iso-propyl carbinol has been prepared from
ethyl iso-butyrate and phenyl magnesium bromide by
Sabatier and Murat (21), Levy (29), Ramart-Lucas and
Salmon-Legagneur (30), Schlenk and Bergmann (28)r and
from iso-propyl magnesium iodide and benzophenone by

-6-

Sabatier and Murat (21). In this laboratory (31) an at­
tempt to prepare it from iso-propyl magnesium bromide
and benzophenone gave benzohydrol as the principal pro­
duct.
Diphenyl n-butyl carbinol has been prepared from
ethyl n-valerate and phenyl magnesium bromide by Schlenk
and Bergmann (26).
Diphenyl iso-butyl carbinol has been prepared from
methyl iso-valerate and phenyl magnesium bromide by
Sabatier and Murat (21) and von Auwers (32).
Diphenyl sec-butyl carbinol has not been prepared
as far as the author has been able to determine.
Diphenyl tert-butyl carbinol has been prepared
from trimethyl acetophenone and phenyl magnesium bromide
(33) by Ramart-Lucas (34), and from the ethyl ester of
trimethyl acetic acid and phenyl magnesium bromide by
Schlenlc and Racky (35) and by Bateman and Marvel (36).
Diphenyl n-amyl carbinol has been prepared from
ethyl caproate and phenyl magnesium bromide by Masson
(23) and Schlenk and Bergmann (26).
For this investigation, the diphenyl alkyl carbin­
ols, with the exception of diphenyl ethyl carbinol,
were prepared from phenyl magnesium bromide and the coresponding acid chlorides, the method of Gilman,
Fothergill, and Parker (24).
2 CgHgMgBr-^- RC0C1

> (C6H 5 )2C (R )OMgBr - h MgBrCl

(C6H5 )2C(R)0MgBr -f- HOI

> (C6H5 )2C (R)OH -H MgBrCl

-7

Diphenyl ethyl carbinol was prepared from ethyl propion­
ate and phenyl magnesium bromide.
In addition, diphenyl n-propyl carbinol, diphenyl
iso-propyl carbinol, and diphenyl n-amyl carbinol were
prepared from the corresponding esters and diphenyl npropyl carbinol was prepared from butyrophenone. The
yields of the carbinols from the acid chlorides and es­
ters were 65$ to 80$.
Diphenyl sec-butyl carbinol was prepared from
methyl ethyl acetyl chloride and phenyl magnesium brom­
ide in 65$ yield. It is a light yellow, viscous liquid.
Its structure was proved by dehydration and oxidation
of the resulting hydrocarbon with chromic acid. Benzo­
phenone and methyl ethyl ketone were isolated, the lat­
ter as its semicarbazone, M.P. 143* (37).
C6H5
H 0-C-CH(CH,) (C2H5)

C6H5

C6H 5
------

»

C=C(CH3) (C2H5) -f- HsO

c6h5

C6H5
C5H5
CrC(CH3 )(C2H5 )-*-Na2Cr2C>7 -t*HAo— * C=0 4-0=C(CH3) (C2H5 )

Cq Rq

CgHs

-8-

Physical Constants of th© Diphenyl Alkyl Carbinols
Compound_____________________ M.P.______________ B.P.
diphenyl ethyl carbinol

94-5°

128-9°/ 1 ram.

diphenyl n-propyl carbinol
diphenyl iso-propyl carbinol

128-30°/ 2 mm.

52-3°

125-6°/ 1 ram.

diphenyl n-butyl carbinol

133-4°/ 1 mm.

diphenyl iso-butyl carbinol

129-30°/ 1 mm.

diphenyl sec-butyl carbinol

126-7°/ 1 ram.

diphenyl tert-butyl carbinol

124-5°/ 1 mm.

diphenyl n-amyl carbinol

46-7°

142-3°/ 1 ram.

Physical Constants of the Dehydration Products of
Compound
M.P.
B.P.
1,1 diphenyl 1-propene

51-2°

94-5°/ 1 mm.

1,1 diphenyl 1-butene

115-6°/ 2 mm.

1,1 diphenyl 2 methyl 1-propene

101-2°/ 1 ram.

1,1 diphenyl 1-pentene

112-3°/ 1 ram.

1,1 diphenyl 3 methyl 1-butene

110-2°/ 1 mm.

1,1 diphenyl 2 methyl 1-butene

108-9°/ 1 ram.

2,2 diphenyl 3 methyl 3-butene

102-3°/ 1 ram.

1,1 diphenyl 1-hexene

130-1°/ 1 mm.

-9-

B.P.

Sp. G.

Index of Refract ion

177-8°/ 16 ram.
178-9°/ 15 ram.

1.0428

.5727

191-2®/ 15 ram.

||o1.0478

njf’l .5658

184-5°/ 15 mm.

If!1.0430

n§5°l .5682

185-6°/ 15 ram.

||I1. 0445

a§5*l .5664

185-6°/ 14 mm.

H ? 1.0546

178-9°/ 15 ram.

.5731

204-5°/ 15 ram.
the Diphenyl Alkyl Carbinols
B.P.
B.P.

Sp. g .

Index of
Refract ion

151-2°/ 16mm. 281-2°/ 743mm.
164-5°/ 15mm. 288-9°/ 743ram.

25*

1.0096

n£° 1.5950

155-6°/ 15mm. 285-6°/ 743ram.

1.0004

ng5°1.5962

180-1°/ 19mm. 300-1°/ 743mm.

||ri.0022

n^5°i.5942

169-70? 18mm. 292-3®/ 743ram.

|^0.9813

n^5°1.5816

165-6°/ 18mm.

0.9944

n^5°1.5822

156-7®/ 15mm.

f 5l 0.9790

n§5°1.5759

180-1°/ 17mm. 305-7®/ 738mm.

P5®
gg*0.9987

n^5*1.5968

-10-

(2) Condensation of the Diphenyl Alkyl Carbinols with
Phenol in the Presence of Anhydrous Aluminum Chloride
The eight diphenyl alkyl carbinols were conden­
sed with phenol by the following procedure:
Anhydrous aluminum chloride is added, with stir­
ring to a mixture of phenol and diphenyl alkyl carbinol
dissolved in petroleum ether. After standing three to
four days, the mixture is decomposed with ice and HC1,
extracted with diethyl ether, and the ether removed.
mV> A

xuo

^

A M a1 A
}jxx^
iasj± sz yjx

4
*

5M

u u io

%wA “
■
»
1
—
4 .■
»

A

iu a u u i c

«
"
*M A

a i o

A AM A
*M A 4
»A A

o c p a x a u o u

A«M

i x u iii

^ V
*A

uno

M AM

xavjii.—

phenolic compounds by the use of alcoholic KOH and pet­
roleum ether. The phenolic and non-phenolic fractions
are separately fractionally distilled.
For the discussion of the products, the condensa­
tions of the eight diphenyl alkyl carbinols with phenol
are divided into three groups involving the condensa­
tions of (1 ) the diphenyl primary-alkyl carbinols, (2 )
diphenyl secondary-alkyl carbinols, and (3) a diphenyl
tert-alkyl carbinol.
(1) Products from the Condensations with Phenol of
the Five Diphenyl primary-Alkyl Carbinols: Diphen­
yl Ethyl Carbinol, Diphenyl n-Propyl Carbinol, Di­
phenyl n-Butyl Carbinol, Diphenyl iso-Butyl Carbin­
ol, and Diphenyl n-Amyl Carbinol.
From the fractional distillation of the non-phen­
olic fractions, two types of compounds were obtained,

-11-

diphenyl alkenes, resulting from the dehydration of the
carbinols, and small amounts of high-boiling, viscous
materials distilling over wide ranges ( 180-250*/ 3 mm*).
These latter materials probably contained dimers of the
diphenyl alkenes but were not investigated because they
occurred in amounts too small to permit their purifica­
tion.
The principal products isolated from the phenolic
fractions were, besides unused phenol, the condensation
products ( p-hydroxy triphenyl primary-alkyl methanes ).
Small amounts of higher boiling materials ( above 230°
at 3 mm. ) were obtained. Because they could not be
crystallized, or distilled without decomposition, they
were not investigated. They may consist of disubstituted
phenols or products resulting from the condensation of
the unsaturated dimers of the diphenyl alkenes with
phenol. Their solubility in aqueous KOH indicates that
they are not disubstituted phenols.
The diphenyl alkenes, 1,1 diphenyl 1-propene, 1,1
diphenyl 1-butene, 1,1 diphenyl 1-pentene, 1,1 diphenyl
2 methyl 1-butene, and 1,1 diphenyl 1-hexene resulting
from the dehydrations of diphenyl ethyl carbinol, diphen­
yl n-propyl carbinol, diphenyl n-butyl carbinol, diphen­
yl iso-butyl carbinol, and diphenyl n-amyl carbinol re­
spectively, were also condensed with phenol with the
formation of the same products as from the condensations
of the corresponding

carbinols with phenol.

-12-

The p-hydroxy triphenyl primary-alkyl methanes
were obtained, for the most part, in yields of 30$ to
40$,
(2) Products from the Condensations with Phenol of
the Two Dinhenyl sec--Alkyl Carbinols: Diphenyl
iso-Propyl Carbinol and Diphenyl sec-Butyl Car­
binol,
From the fractional distillation of the non-phenolic fraction, obtained from the condensation of diphenyl
iso-propyl carbinol with phenol, were isolated iso­
propyl benzene, 1,1 diphenyl 2 methyl 1-propene ( from
the dehydration of the carbinol ), and a small amount
of a viscous liquid ( B.P. 200-50°/ 3 mm.). This vis­
cous material was not investigated.
From the phenolic fraction were isolated unused
phenol, p-benzyl phenol, p-hydroxy triphenyl iso-propyl
methane, and a small amount of higher boiling material
( above 220°/ 3 mm.) which decomposed on distillation.
The yields of p-hydroxy triphenyl iso-propyl methane
varied greatly ( from 9$ to 73$ )•
Identical products were obtained from the conden­
sation of 1,1 diphenyl 2 methyl 1-propene with phenol.
From the condensation of diphenyl sec-butyl ce.rbinol with phenol were obtained, in the non-phenolic
fraction, sec-butyl benzene, 1,1 diphenyl 2 methyl 1butene, and a small amount of high boiling, viscous ma­
terial, and, in the phenolic fraction, phenol, p-benzyl

-13

phenol, p-hydroxy triphenyl sec-hutyl methane, and a
small amount of higher boiling material. The yields of
p-hydroxy triphenyl sec-butyl methane were 12# and 13#.
Because it could not be obtained in sufficient
amounts, 1,1 diphenyl 2 methyl 1-butene was not conden­
sed with phenol.
In two condensations of diphenyl iso-propyl carbin­
ol and diphenyl sec-butyl carbinol with phenol, where
the condensation mixtures were decomposed with ice only
and the phenolic and non—phenolic fractions immediately
separated with the use of alcoholic KOH and petroleum
ether, small alounts of the carbinol were recovered in
the non-phenolic fractions. Apparently, in the presence
of HC1, the temperature necessary to remove the diethyl
ether is sufficiently high to cause dehydration of the
carbinols.
(3) Products from the Condensation of Diphenyl
tert-Butyl Carbinol with Phenol
The attempted condensation of diphenyl tert-butyl
carbinol with phenol, by the procedure used for the
other carbinols, gave only phenol, 2,2 diphenyl 3 methyl
3-butene, and 2,2 diphenyl 3 chloro 3 methyl butane.
When a mixture of phenol and diphenyl tert-butyl car­
binol, dissolved in petroleum ether, was added dropwise,
with stirring, to anhydrous aluminum chloride suspended
in petroleum ether, a 6# yield of 2,2 diphenyl 3 (p-hydroxy phenyl) 3 methyl butane was obtained. The conden­

-14-

sation of P.,2 diphenyl 3 methyl 3-hutene , the dehydra­
tion product of diphenyl tert-hutyl carbinol, with phen­
ol gave a 15% yield of 2,2 diphenyl 3 (p-hydroxy phenyl)
3 methyl butane. In the condensations with diphenyl
tert-butyl carbinol and 2,2 diphenyl 3 methyl 3-butene,
only very small amounts of higher boiling materials
were formed.

-15-

Pro&uots of the Condensation of the Diphenyl
Alkyl Carbinols with Phenol
Condensation Product

B.P.

B.P.

p-hydroxy triphenyl
ethyl methane

198-199°/ 1 ram.

259-260°/ 15 ram.

p-hydroxy triphenyl
n-propyl methane

196-197°/ 1 mm.

256-257®/ 15 ram.

p-hydroxy triphenyl
iso-propyl methane

198-199*/ 1 mm.

*245-255°/ 16 mm.

p-hydroxy triphenyl
n-butyl methane

182-183°/ 1 ram.

237-238°/ 13 ram.

p-hydroxy triphenyl
iso-butyl methane

196-197°/ 1 mm.

261-262°/ 15 ram.

p-hydroxy triphenyl
sec-butyl methane

195-196°/ 1 mm.

#p-hydroxy triphenyl
tert-butyl methane

205-206°/ 1 mm.

2,2 diphenyl 3 methyl
3 (p-hydroxy phenyl) butane
p-hydroxy triphenyl
n-amyl methane

195-200°/ 1 mm.

183-184°/ 1 mm.

256-257°/ 15 ram.

* The distillation of p-hydroxy triphenyl iso-propyl
methane at 16 mm. resulted in noticible decomposition.
# The p-hydroxy triphenyl tert-butyl methane was pre­
pared from diphenyl tert-butyl chloro methane and
p-anisyl magnesium bromide.

-16

Molecular
------ ...

x-w*

113-3.5°

*

*

*

Calculated
— a -----

Determined

C2lH 220

87.46%

6.99%

87.21%

7.22%

C32HS2°

87.37%

7.33%

87.30%

7.40%

C22H22°

87.37%

7.33%

87.25%

7.32%

C23H24°

87.30%

7.64%

87.30%

7.75%

C23h 24°

87.30%

7.64%

87.15%

7.75%

°23H24°

87.30%

7.64%

87.18%

7.62%

C23h 24°

87.30%

7.64%

87.38%

7.36%

0 23324°

87.30%

7.64%

87.55%

7.84%

°24H 26°

87.22%

7.90%

87.20%

7.98%

* These compounds were crystallized but, due to their
great viscosities and low melting points, they failed
to lose their crystalline form when heated above their
melting points.

-17

(3) preparation of Derivatives
The preparation of solid derivatives of the p-hydroxy triphenyl alkyl methanes and of 2,2 diphenyl 3 (phydroxy phenyl) 3 methyl butane was exceedingly diffi­
cult and not very successful. The derivatives attempted
were: phenyl urethanes, alpha naphthyl urethanes, di­
phenyl urethanes, aryloxy acetic acids, p-nitro benzyl
ethers, bromo derivatives, nitro derivatives, and the
benzene sulfonyl, p-bromo benzene sulfonyl, benzoyl,
p-anisoyl, 3,5 dinitro benzoyl, p-ohloro benzoyl, and
p-bromo benzoyl esters. The derivatives that were suc­
cessfully prepared are described, in tabular form, on
pages 18 and 19.

-18-

Derivatives of the p-Hydroxy Triphenyl Alley1 MethButane
Parent Compound_______ Derivat ive____________ M.P.
p-hydroxy triphenyl
ethyl methane

benzoyl
ester

p-hydroxy triphenyl
ethyl methane

p-bromo benzene
sulfonyl ester

p-hydroxy triphenyl
n-propyl metheme

3,5 dinitro
benzoyl ester

133-4°

p—hydroxy triphenyl
n-butyl methane

p—chloro
benzoyl ester

158-9°

2,2 diphenyl 3 (p-hydroxy
phenyl) 3 methyl butane
p-hydroxy triphenyl
tert-butyl methane

p-chloro
benzoyl ester

p-chloro
benzoyl ester

106-6.5°

*121®( needles
*129°( cubes )

183-4°

169-70°

* The derivative crystallized in two crystalline forms*
The analyses of halogen were carried out by the l^arr
bomb method. The analysis of nitrogen was by the micro
Dumas method.

anes and 2,2 Diphenyl 3 (p-Hydroxy Phenyl) 3 Methyl
Molecular
Analyses
Formula____________ Calculated___________ Determined
C28h 24°2

C-85.67#

H-6.16#

C-85.55%

H-6.29#

C27H2303SBr

Br-15.75#

Br-15.61%

c 29H24°6N 2

N-5.64$

N-5.80#

C30H27°2C1

Cl-7.79%

Cl-7.75^

C30H2702C1

Cl-7.79$

Cl-7.90^

C30H27°2C1

Cl—7•79$

Cl-7.62$

-20-

(4 ) Identification of Compounds and Proofs of Structure
The compounds, other than the condensation

prod­

ucts, which were isolated from the condensations of the
diphenyl alkyl carbinols with phenol, were identified
as follows:
1.1 Diphenyl 1-propene was identified by its melt­
ing point.
1.1 Diphenyl 1-butene, 1,1 diphenyl 2 methyl 1-propene, 1,1 diphenyl 1-pentene, 1,1 diphenyl 3 methyl 1butene, 1,1 diphenyl 2 methyl 1-butene, and 1,1 diphenyl
1-hexene were identified by their physical constants
( boiling points, densities, and indices of refraction ).
2.2 Diphenyl 3 methyl 3-butene was identified by
converting it to 2,2 diphenyl 3 chloro 3 methyl butane
by the method of Bateman and Marvel (36). 2,2 Diphenyl
3 chloro 3 methyl butane was identified by its melting
point, 108-9°(34).
Diphenyl iso-propyl carbinol was identified by its
melting point.
Diphenyl sec-butyl carbinol was identified by its
physical constants.
p-Benzyl phenol was identified by its melting point
and by its mixed melting point with a sample of p-benz­
yl phenol prepared from benzyl chloride, phenol, and
aluminum chloride.
Iso-propyl benzene and sec-butyl benzene were iden-

-21-

tifled by the melting points of their p-acetamino der­
ivatives (106* and 126°), prepared by the method of
Ipatieff and Schmerling (38).
The proof of structure of the condensation product
of diphenyl methyl carbinol and phenol was accomplished
by Welsh and Draice (6) by allowing the chloride of the
carbinol to react with p-anisyl magnesium bromide and by
subsequent conversion of the methoxyl group to a hydrox­
yl. The compound, p-hydroxy triphenyl methyl methane,
was also prepared by Julian and Gist (39) from fuchsone
( diphenyl methylene quinone ) and methyl magnesium
iodide and they prepared the corresponding methoxy com­
pound from p-anisyl diphenyl chloro methane and methyl
magnesium iodide.
The method of Welsh and Drake was not thought to
be generally desirable, except for the synthesis of phydroxy triphenyl tert-butyl methane, for the following
reasons: The chlorides of the diphenyl primary-alkyl
and diphenyl seoondary-alkyl carbinols are difficult to
prepare. They eliminate HC1 at room temperature to form
the diphenyl alkenes. The point of attachment of the
chlorine atom is not prooved. Their use involves the as­
sumption that the OH of the carbinol is replaced direct­
ly by Cl or, in case the reaction takes place by prelim­
inary dehydration and addition of HC1 to the resulting
double bond, the assumption that the chlorine atom is

-22-

directed to the position previously held hy the hydrox­
yl group. This latter assumption is supported by Markownikoff*s rule for the chlorides of the diphenyl pri­
mary-alkyl carbinols but not for the chlorides of the
diphenyl secondary-alkyl carbinols. The chloride of di­
phenyl tert-butyl carbinol is readily prepared, stable,
and its structure has been established by Ramart-Lucas
(34).
The synthesis of the p-hydroxy triphenyl alkyl
methanes from p-anisyl diphenyl methyl halides and al­
kyl magnesium halides ( one of the methods of Julian
and Gist ) was tried without success. The reactions of
p-anisyl diphenyl chloro methane with ethyl magnesium
bromide and of p-anisyl diphenyl bromo methane with
sec-butyl magnesium bromide both gave p-anisyl diphenyl
methane instead of the desired products, p-anisyl di­
phenyl ethyl methane and p-anisyl diphenyl sec-butyl
methane. Apparently this method is successful only when
the Grignard reagent used is incapable of exhibiting
any reducing action. Two attempts to prepare fuchsone
by the method of Bistrzycki and Herbst (41) were unsuc­
cessful.
The structure of the condensation product of di­
phenyl n-butyl carbinol and phenol was proved by the
following method:
p-Anisyl diphenyl carbinol was prepared from

-23-

p-anisyl magnesium bromide and benzophenone and from
p-anisoyl chloride and phenyl magnesium bromide. It was
condensed with malonic acid ( and the product decarboxylated ) by the method of Fosse (42) to give 3,3,3 panisyl diphenyl propanoic acid. The acid chloride was
prepared with the use of thionyl chloride and allowed
to react with ethyl magnesium bromide. The resulting
ketone, 1,1,1 p-anisyl diphenyl 3-pentanone, was red­
uced by the Clemmensen method (40) and the methoxyl
group changed to hydroxyl by the procedure of Welsh and
Drake (6). The p-chloro benzoyl esters of the condensa­
tion product and the synthesized product melted at
158-9

, mixed melting point 158-9 .
In an attempt to establish the structure of the

condensation product of diphenyl iso-propyl carbinol and
phenol, diphenyl iso-propyl chloro methane, prepared
from the carbinol and dry HC1 gas, was allowed to re­
act with p-anisyl magnesium bromide. The product was
converted to p-hydroxy triphenyl iso-propyl methane
( or 1,1 diphenyl 2 (p-hydroxy phenyl) 2 methyl propane)
by refluxing with conc. HBr and phenol. No solid der­
ivatives of this product or of the condensation pro­
duct could be prepared.
p-Hydroxy triphenyl tert-butyl methane, the expect­
ed condensation product of diphenyl tert-butyl carbinol
and phenol, was synthesized from p-anisyl magnesium

-24

bromide and diphenyl tert-butyl chloro methane (34),
with subsequent demethylation by the usual procedure.
The condensation product was compared with it and found
to be different. The condensation product was found to
be identical, by mixed melting points of the p-chloro
benzoyl esters, with the product obtained from the con­
densation of 2,2 diphenyl 3 methyl 3-butene with phenol.
It was therefore assumed to be 2,2 diphenyl 3 (p-hydroxy
phenyl) 3 methyl butane. To establish its structure
more definitely, attempts were made to condense 2,2 di­
phenyl 3 chloro 3 methyl butane (36) with phenol in the
presence of aluminum chloride, with sodium phenolate in
toluene solvent, and with p-anisyl magnesium bromide.
All three attempts were unsuccessful.

-25-

(5) Interpretation of Results
In the condensation of tert-alcohols with phenol
in the presence of aluminum chloride, two of the mechan­
isms advanced have been, (1) direct elimination of water
from the OH of the carbinol and the para H of the phen­
ol, and (2) dehydration of the carbinol followed by ad­
dition of phenol to the resulting

c6H5
(1) CH3CH2C-joH

ethylenic double bond.

^
H jC6H 40H

c6H5
>

CHgCHgC-CgH^OH

C6H5

C6H s

C*H5
C6H5
(2) CH3CH2C0H-------- >CH3CH=C

CgHg
CH3CH“—OCa H r
\
i
h ~ c 6h 4 o h

HgO

4

- -

H20

C6H5
96^5
> CH3CH2c-CrHaOH
3

The ’direct* condensations of the diphenyl primary-alkyl and dipheny secondary-alkyl carbinols with phenol
would be expeoted to give the same products as would
the condensations of the carbinol*s dehydration pro­
ducts. Thus, the fact, that the carbinols and the cor­
responding diphenyl alkenes both condense with phenol
to give identical products, demonstrates only that the
second mechanism is a definite possibility.
In one condensation of diphenyl ethyl carbinol
with phenol, in which less than the theoretical amount
of aluminum chloride ( The theoretical amount is assum­

-26-

ed to be one mole of aluminum chloride to three moles of
the carbinol.) was added to the solution of the carbinol
and phenol in petroleum ether, a small yield (19$) of
p-hydroxy triphenyl ethyl methane was obtained. If com­
plete dehydration of the carbinol were necessary before
any condensation could take place, no condensation pro­
duct would have been formed. This evidence, though far
from being conclusive, favors the first mechanism.
In the condensation of diphenyl tert-butyl carbin­
ol with phenol, ‘direct1 condensation would be expected
to give p-hydroxy triphenyl tert-butyl methane. Conden­
sation by the second mechanism, as well as condensation
of the dehydration product ( 2,2 diphenyl 3 methyl 3butene ) with phenol, would be expected to give 2,2 di­
phenyl 3 (p-hydroxy phenyl) 3 methyl butane. The pro­
ducts obtained from the condensation of the carbinol
and of its dehydration product were proved to be iden­
tical, Therefore, at least in the case of diphenyl
tert-butyl carbinol, the condensation takes place by
the second mechanism. The failure of 2,2 diphenyl 3
chloro 3 methyl butane to condense with phenol elimin­
ates the chloride as a possible intermediate.
The formation of p-benzyl phenol and iso-propyl
benzene and p-benzyl phenol and seo-butyl benzene re­
spectively from the condensations of diphenyl iso­
propyl carbinol and diphenyl sec-butyl oarbinol with

-27-

phenol was first thought to result from the breakdown
( with hydrogenation ) of the condensation products
under the influence of aluminum chloride.
CgH5
RCH( CH3 )C C g H ^ H

2 H — ► C6H5CH2C6H 40H

C6H5CH (CH3 )R

Ce«5
The isolation of p-benzyl phenol from the products
formed when p-hydroxy triphenyl iso-propyl methane is
distilled, with decomposition, at 15 mm. pressure, sup­
ported this idea. However, when p-hydroxy triphenyl
iso-propyl methane was dissolved in ligroin and treated
with aluminum chloride, no p-benzyl phenol or iso-prop­
yl benzene could be isolated. The products isolated, in
addition to undecomposed p-hydroxy triphenyl iso-propyl
methane and higher boiling materials, were phenol and
1,1 diphenyl 2 methyl 1-propene. Thus, it appears that
p-benzyl phenol and the sec-alkyl benzene are formed
during the process of condensation and not by decompo­
sition of the condensation product. The hydrogen donor
was not determined.

-28-

Condensations with Phenol
Carbinol

Phenol
grams moles

grams

moles

diphenyl ethyl carbinol

106

1/2

94

1

diphenyl ethyl carbinol

106

1/2

94

1

diphenyl ethyl carbinol

53

1/4

47

1/2

diphenyl ethyl carbinol

53

1/4

24

1/4

diphenyl n-propyl carbinol

45

1/5

40

diphenyl iso-propyl carbinol

113

1/2

73

3/4

diphenyl iso-propyl oarbinol

113

1/2

73

3/4

diphenyl n-butyl carbinol

120

1/2

73

3/4

diphenyl iso-butyl carbinol

120

1/2

73

3/4

diphenyl sec-butyl carbinol

120

1/2

73

3/4

diphenyl tert-butyl carbinol

120

1/2

73

3/4

diphenyl tert-butyl carbinol

60

1/4

37

3/8

127

1/2

73

3/4

diphenyl n-amyl carbinol

A1C13
grams moles

Condensation Product
grams
% yield

35

1/4

57

40

35

1/4

126

87

10

1/14

14

19

35

1/4

10

14

26

46

15

p-Benzyl
Phenol

Alkyl
Benzene

35

1/4

14

19

15 g.

10 g.

35

1/4

110

73

15 g.

10 g.

35

1/4

48

30

35

1/4

63

40

35

1/4

21

13

33 g«

10 g.

35

1/4

no condensation

18

1/8

4

6

55

1/4

46

30

-30-

Condensations with Phenol
Compound
grams moles
1,1 diphenyl 1-propene

64

1,1 diphenyl 1-butene

90

1/3

Phenol
grams moles
40
47

1/2
1/2

1,1 diphenyl 2 methyl 1-propene 105

1/2

47

1,1 diphenyl 2 methyl 1-propene

85

2/5

55

1,1 diphenyl 1-pentene

75

1/3

35

1/3

1,1 diphenyl 3 methyl 1-butene

75

1/3

35

1/3

1,1 diphenyl 3 methyl 1-butene

55

1/4

35

1/3

2,2 diphenyl 3 methyl 3-butene

40

1/6

35

1/3

1,1 diphenyl 1-hexene

80

1/3

35

1/3

2,2 diphenyl 3 chloro
3 methyl butane

65

1/4

47

1/2

-31

AlClrj
Condensation Product
p-Benzyl
Alkyl
grams moles
grams
jo yield______ Phenol_____Benzene
5

54

56

20

50

42

5

17

11

_ _ —

20

57

47

3 g.

40

36

5

15

14

15

14

18

8

15

5

4

25

25

1/6

1/6

5
25

1/6

no condensation

----------

5 g.

-32-

IV Experimental
Preparation of the Diphenyl Alkyl Carbinols
In a dry 3 L. 3 neok round bottom flask, fitted
with separatory funnel and CaClg tube, reflux condenser
and CaClg tube, and mechanical stirrer with glycerol
seal, place 60 g. magnesium, a few crystals of iodine,
and 10 g. bromo benzene dissolved in 100 cc. anhydrous
ether. Heat the mixture on the water bath until the re­
action begins. Remove the water bath and then add, with
stirring, a solution of 377 g. bromo benzene in 1 L. an­
hydrous ether at such a rate that the mixture refluxes
gently. Continue stirring for one hour after addition
is complete.
To the Grignard reagent, add dropwise, with cool­
ing and stirring, one mole of acid chloride or ethyl
ester ( or two moles of phenyl alkyl ketone ) dissolved
in 500 cc, anhydrous ether.
Decompose the mixture with ice and add sufficient
conc. HC1 to barely dissolve the basic magnesium salts
that are formed. Separate, and extract the aqueous lay­
er twice with 300 cc. portions of ether. Dry the combin­
ed ether solutions with a mixture of anhydrous NagS04
and anhydrous Na2C03 . After removal of the ether (steam
bath), the remaining liquid is cooled and allowed to
crystallize or is fractionally distilled at 2-3 mm.
pressure. The yield is 65-90% of the theoretical, based

-33-

on the aoid chloride, ester, or ketone.
Condensation of the Diphenyl Alkyl Carbinols ( and
Diphenyl Alkenes ) with Phenol
In a 1 L, 3 neck round bottom flask, fitted with
mechanical stirrer and glycerol seal, and CaClg tube,
place 70 g. phenol, 1/2 moles diphenyl alkyl carbinol
( or diphenyl alkene ), and 100 cc, petroleum ether. To
the mixture, with stirring, add 35 g. anhydrous alum­
inium chloride in small portions over a period of two
hours. Continue stirring for 4-6 hours and allow the
mixture to stand for 3-4 days.
Decompose the mixture with ice and HC1, separate
the petroleum ether layer, and extract the aqueous lay­
er twice with 50 cc. portions of diethyl ether. Combine
the ether solutions and remove the ether ( steam bath ),
To the residue add 500 cc. alcoholic K0H ( 1 g, K0H /
5 g. HgO / 4 g. methyl alcohol ) and extract the mix­
ture twice with 100 cc. portions of petroleum ether.
The petroleum ether extracts are combined, dried with
anhydrous NagS04 , the ether removed ( steam bath ), and
the residue subjected to fractional distillation. The
alcoholic K0H layer is acidified with 1-1 HC1 and twice
extracted with 100 cc. portions of diethyl ether, the
ether removed ( steam bath ), and the residue fraction­
ally distilled. The condensation product, which occurrs

-34-

in this fraction, boils in the neighborhood of 190 to
230°/ 3 mm. pressure.
Condensation of Diphenyl tert-Butyl Carbinol with
Phenol
In a 500 cc. 3 neck round bottom flask, fitted
with mechanical stirrer and glycerol seal, CaCl2 tube,
and separatory funnel, place 20 g. anhydrous aluminum
chloride and 100 cc. petroleum ether. Add dropwise,
with stirring, a solution of 60 g. diphenyl tert-butyl
carbinol and 37 g. phenol in 100 cc. petroleum ether,
over a period of one hour. Continue stirring for 4-6
hours and allow the mixture to stand 3-4 days. The re­
maining procedure is identical with the preceding one.
Synthesis of p-Hydroxy Triphenyl n-Butyl Methane
In a 1 L. 3 neok round bottom flask, fitted with
mechanical stirrer and glycerol seal and condenser set
for downward distillation, place 290 g. malonic acid
and 115 g. p-anisyl diphenyl carbinol. Heat on an oil
bath, with stirring, at 120-30° for six hours and then
raise the oil bath temperature to 170-80® for an addi­
tional hour. Discard the distillate, which consists of
water and acetic acid, cool the remaining liquid, and
add 300 cc. 20°Jo alcoholic K0H

and reflux for two hours.

Cool the mixture, dilute it with an equal volume of
water, and extract it with 100 cc. ether. The ether

-35-

layer, which contains p-anisyl diphenyl carbinol, is
discarded. To the alooholio KOH layer, add sufficient
cono. HC1 to make the solution acid to Congo Red paper,
cool, and extract the solution twice with 100 cc. por­
tions of ether. Combine the extracts and dry with anhyd­
rous NagS04 . Distill off the ether ( steam bath ) and
remove the last traces of ether and malonic acid by
heating on an oil bath at 180° under reduced pressure.
The yield of crude 3,3,3 p-anisyl diphenyl propanoic
acid is 85 g.
To the crude acid, add 50 g. thionyl chloride and
reflux the mixture for three hours. Remove the excess
thionyl chloride by distillation. The last traces of it
are removed by heating on an oil bath at 180° under red­
uced pressure. Crude 3,3,3 p-anisyl diphenyl propanoyl
chloride is a dark red, glassy, non-crystalline solid.
In a 250 oc. erlenmeyer flask fitted with reflux
condenser and CaCl2 tube, place 1.5 g. magnesium and a
few small crystals of iodine. Add 50 cc. anhydrous eth­
er and 1 oc. ethyl bromide and warm the flask ( water
bath ) until the reaction begins. Add, in small portions,
6 g. ethyl bromide dissolved in 75 cc. anhydrous ether,
allowing the reaction to subside after each addition.
In a 500 cc. erlenmeyer flask fitted with a reflux
condenser, place 20 g. 3,3,3 p-anisyl diphenyl propan­
oyl chloride dissolved in 200 cc. anhydrous ether. In

-36-

the top of the condenser, place a 250 oc. separatory
funnel held in place by a notched cork. Through the
separatory funnel, add dropwise, with cooling and agi­
tation, the solution of ethyl magnesium bromide. Decom­
pose the mixture with ice and HC1 and extract it with
400 oc. ether. Wash the ether layer with 10$ Na^COs
solution and remove the ether ( steam bath ). The resi­
due is crude 1,1,1 p-anisyl diphenyl 3-pentanone,
yield, 18 g.
The 1,1,1 p-anisyl diphenyl 3-pentanone is reduced
to p-anisyl diphenyl n-butyl methane by the Clemmensen
method (40) and the latter is converted to p-hydroxy
triphenyl n-butyl methane by the method of Welsh and
Drake (6).
Synthesis of p-Hydroxy Triphenyl iso-Propyl Meth­
ane and p-Hydroxy Triphenyl tert-Butyl Methane
In a dry 1 L. 3 neck round bottom flask fitted
with reflux condenser and CaClg tube, mechanical stir­
rer and glycerol seal, and separatory funnel, place 6 g.
magnesium and a few crystals of iodine. Add a solution
of 2 g. p-bromo anisole in 50 cc. anhydrous ether and
warm ( water bath ), with stirring until the reaction
begins. Add dropwise, with stirring, a solution of 48 g.
p-bromo anisole in 100 cc. anhydrous ether at such a
rate that the mixture refluxes gently. After addition
is complete, continue stirring for 2-3 hours.

-37-

To the p-anisyl magnesium bromide thus prepared,
add slowly 30,5 g, diphenyl iso-propyl chloro methane
( or 32 g, diphenyl tert-butyl chloro methane ) dissol­
ved in 100 cc, anhydrous ether. The flask is then trans­
ferred to the steam bath, the ether removed, and the
residue heated at 90-100° for 6-8 hours. The residue is
decomposed with ice and HC1 and extracted with ether.
The ether is removed ( steam bath ) and the residue is
distilled under reduced pressure. The fraction boiling
at 180-220° / 3 mm, is crude p-anisyl diphenyl iso-propyl methane { or p-anisyl diphenyl tert-butyl methane).
The p-anisyl diphenyl iso-propyl methane and p- anisyl
diphenyl tert-butyl methane are converted to p-hydroxy
triphenyl iso-propyl methane and p-hydroxy triphenyl
tert-butyl methane by the method of Welsh and Drake (6),
Diphenyl iso-propyl chloro methane was prepared
from diphenyl iso-propyl carbinol and dry HC1:
In a 100 cc. separatory funnel, plaoe 28 g. diphen­
yl iso-propyl carbinol dissolved in 25 cc. benzene, and
10 g. CaClg. Surround the separatory funnel with icewater and bubble dry HC1 gas through the solution of the
carbinol, at the rate of 4-5 bubbles a second, for one
hour. Immediately transfer the separatory funnel to the
flask containing the p-anisyl magnesium bromide and add
the solution of diphenyl iso-propyl chloro methane to
the Grignard reagent, ( Diphenyl iso-propyl chloro meth-

-38-

an© is very difficult to prepare because it spontaneous­
ly gives off HC1, at room temperature, to form 1,1 di­
phenyl 2 methyl 1-propene. Its preparation was attempted
unsuccessfully five times before it was finally obtained.
Diphenyl tert-biityl chloro methane was prepared
from diphenyl tert-butyl carbinol and thionyl chloride.
The excess of thionyl chloride was removed by heating
at 60

under reduced pressure.

Preparation of the p-Chloro Benzoyl Esters
In a 6 in. pyrex test tube, place 1.5 g. of the
phenol and 1 g. of p-chloro benzoyl chloride. Heat the
mixture gently with a very small flame until HC1 fumes
cease to be evolved. Reflux the mixture very gently for
an additional five minutes, cool, and add 5 g. solid
NagCOg and 20 cc. water and heat the mixture ( steam
bath ) for 4-5 hours to hydrolise the excess acid chlor­
ide. Cool the tube, place its contents in a 250 cc. sep­
aratory funnel, and dissolve the ester with 100 cc.
ether. Wash the ether solution with 1 0 % Na2C03 solu­
tion, dry with anhydrous Na2S04 , and evaporate the ether
solution to dryness. Recrystallize the ester from
ligroin.

-39-

V

Summary

(1) Five of the diphenyl primary-alkyl carbinols have
been condensed with phenol to give the expected p-hyd­
roxy triphenyl primary alkyl methanes.
(E) Two of the diphenyl secondary alkyl carbinols have
been condensed with phenol to give the p-hydroxy tri­
phenyl secondary-alkyl methanes, p-benzyl phenol, and
secondary alkyl benzenes.
(3) Diphenyl tert-butyl carbinol has been condensed with
phenol to give E,E diphenyl 3 (p-hydroxy phenyl) 3 meth­
yl butane.
(4) p-Hydroxy triphenyl tert-butyl methane has been
synthesized.
(5) The structure of one of the p-hydroxy triphenyl pri­
mary alkyl methanes has been established by synthesis.
(6) A new alcohol, diphenyl sec-butyl carbinol, has
been prepared, its structure established, and some of
its physical constants determined.

-40-

VI

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(2)

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-41-

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-42

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