Org. Synth. 1946, 26, 21
DOI: 10.15227/orgsyn.026.0021
DI-(p-CHLOROPHENYL)ACETIC ACID
[Acetic acid, di-(p-chlorophenyl)]
Submitted by Oliver Grummitt, Allen Buck, and Richard Egan.
Checked by Lee Irvin Smith, R. T. Arnold, and Paul N. Craig.
1. Procedure
A mixture of 400 ml. of diethylene glycol (Note 1) and 49.5 g. (0.14 mole) of 1,1-di-(p-chlorophenyl)-2,2,2-trichloroethane (Note 2) is placed in a 1-l. three-necked flask fitted with a stirrer, a reflux condenser, and a thermometer. To this is added a solution of 63 g. (1.12 mole) of potassium hydroxide in 35 ml. of water. The mixture is stirred and refluxed for 6 hours at such a rate that the temperature is maintained at 134–137° (Note 3) and (Note 4). The mixture is allowed to cool and, with vigorous stirring, is poured into 1 l. of cold water. The insoluble material is filtered and washed twice with 50-ml. portions of warm water (Note 5). The filtrate is then boiled gently for 5 minutes with 2 g. of Norit; the carbon is removed, the filtrate is acidified to litmus with 20% sulfuric acid (approximately 120 ml.), and then an additional 30 ml. of acid is added. The mixture is cooled to 0–5°; the precipitate is collected by filtration under suction, washed free of sulfate ions with water, and dried at 100–110°. The product is di-(p-chlorophenyl) acetic acid melting at 163–165°; it weighs 27–28.5 g. (69–73%). For purification, this material is dissolved in 100 ml. of boiling 95% ethanol, the solution is filtered, and approximately 45 ml. of water is added to the boiling filtrate until it just becomes turbid. The solution is then cooled to 0–5°, and the solid is removed by suction filtration. The material weighs 25–26 g. and melts at 164–166°.
2. Notes
1.
Diethylene glycol with a boiling range of 230–270°, from Carbide and Carbon Chemicals Corporation, is satisfactory.
2.
A purified grade of
1,1-di-(p-chlorophenyl)-2,2,2-trichloroethane (DDT) melting at
105–106° should be used. It can be obtained by crystallizing the technical material from
ethanol. Thus,
100 g. of technical DDT melting at
81–96°, when crystallized from
550 ml. of 95% ethanol, gave about
70 g. of material melting at
105–106°.
3.
The intermediate product,
1,1-di-(p-chlorophenyl)-2,2-dichloroethylene,
1,2 can be isolated readily. The mixture is gradually (7–8 minutes) heated to reflux temperature and is then refluxed 2 minutes. The mixture is cooled and poured into 1 l. of cold water, and the product is removed by suction filtration, washed well with water, and dried. The yield of crude product melting at
83–86° is
43.5 g. (
97%). This may be purified by crystallization from
200 ml. of 95% ethanol; the product weighs
39.5 g. and melts at
86.5–88°.
4.
Longer reaction times or higher temperatures favor the formation of
di-(p-chlorophenyl) methane; see Note 5.
5.
The insoluble material consists of
silica,
1,1-di-(p-chlorophenyl)-2,2-dichloroethylene and a small amount of
di-(p-chlorophenyl) methane3 (melting at
54–55° when purified), formed by decarboxylation of the acid.
3. Discussion
Di-(p-chlorophenyl) acetic acid has been made by the action of
alcoholic potassium hydroxide on
1,1-di-(p-chlorophenyl)-2,2-dichloroethane;
2,4 by the action of
barium hydroxide on DDT in
ethylene glycol;
4 and by the condensation of
chlorobenzene with
glyoxylic acid.
4
This preparation is referenced from:
Appendix
Chemical Abstracts Nomenclature (Collective Index Number);
(Registry Number)
silica
1,1-di-(p-chlorophenyl)-2,2,2-trichloroethane (DDT)
alcoholic potassium hydroxide
ethanol (64-17-5)
sulfuric acid (7664-93-9)
carbon,
Norit (7782-42-5)
chlorobenzene (108-90-7)
potassium hydroxide (1310-58-3)
ethylene glycol (107-21-1)
barium hydroxide (17194-00-2)
glyoxylic acid (298-12-4)
diethylene glycol (111-46-6)
Di-(p-chlorophenyl)acetic acid,
Acetic acid, di-(p-chlorophenyl) (83-05-6)
1,1-di-(p-chlorophenyl)-2,2,2-trichloroethane (50-29-3)
1,1-Di-(p-chlorophenyl)-2,2-dichloroethylene (72-55-9)
di-(p-chlorophenyl) methane (101-76-8)
Di-(p-chlorophenyl) acetic acid
1,1-di-(p-chlorophenyl)-2,2-dichloroethane (72-54-8)
Copyright © 1921-, Organic Syntheses, Inc. All Rights Reserved