4157
COMMUNICATIONS TO THE EDITOR
Dec., 1949
TABLE I DI-(p-CHLOROPHENYL) -ACETIC ACIDDERIVATIVES Compound
1 2 3 4 5 6 7 8 9 10
Methyl di-(p-chlorophenyl)-acetate Phenacyl di-(p-chloropheny1)-acetate Di-(p-chloropheny1)-aceticanhydride 2-(p,p'-Dichlorobenzhydryl)-benzimidazole Di-(p-chloropheny1)-acetylchloride Di-(p-chloropheny1)-acetamide Di-(p-chloropheny1)-acetanilide" Di-(p-chlorophenyl)-aceto-4-chloroanilide p,p'-Dichlorobenzhydryl phenyl ketone Di-(p-chloropheny1)-acetonitrileb
M. p., 'C. c d
Formula
37-39 132-133 104-105.5 246-248 Oil 152-154 205-206 258-260 9C-91 85-86
Ci5HizC120 CzzHlaC1~03 Cz8Hi8C1403 CzoHlaClzNz Ci4H~C130 CirH1iClzNO CzoHibClzNO CnoHl4ClaNO CzoHiaClzO Ci4HsClzN
Chlorine, % Nitrogen, % Mol. wt. Calcd. Found Calcd. Found Calcd. Found
24.6 17.8 26.1 20.1 35.4 25.3 19.9 27.2 20.9 27.1
24.2 17.9 26.3 19.4 34.9 25.0 19.9 27.3 20.9 25.8
295 295' 399 378 544 5480 7.95 7.81 5.00 4.60 3.93 4.03 3.59 3.65 341 353A 5.34
5.62
a Described by Gatzi and Stammbach, Helv. Chim. Acta, 29, 563 (1946), as melting 202-204' in a paper published after These m. p.'s Despite the sharp m. p., analysis shows that this compound is not pure. our synthesis had been done. are uncorrected. The m. p.'s of the corresponding diphenylacetic acid (m. p. 148-149') dtrivatives were taken from the In these exliterature for comparison; they are 1, 60'; 3, 98'; 5, 56-57'; 6, 167-168'; 7, 180-181 ; 9, 13C-137'. amples the diphenylacetic acid derivatives frequently are higher melting. e Saponification values of this ester ran 7.5-100% over the calculated, probably as the result of a secondary reaction of phenacyl alcohol with alkali. Boiling point rise molecular weights in benzene gave high values, indicative of association. This value was found by the Rast camphor By neutral equivalent. * By b. p. rise in benzene. method. f By saponification equivalent.
partially crystallized to give 1.5 g. of solid melting 83-85 '. Crystallization from 10 ml. of 95% ethanol gave 1.0 g. (18%) melting 85-86". Despite the sharp melting point, analysis indicated an impure compound.
COMMUNICATIONS
SHERWIN-WILLIAMS LABORATORY WESTERNRESERVEUNIVERSITY OLIVERGRUMMITT CLEVELAND 6, OHIO DEANMARSH RECEIVED AUGUST15,1949
pro
Dist. temp.,
GEOMETRIC ISOMERS OF 1-PHENYL-1 ,J-BUTADIENE
Sir :
T H E EDITOR
OC. Mm. C ~ S
F. p., OC.
71 11 -56.99 t 0 . 0 4
dZ%
0.9197
nzb
Molar ref.a
1.5822 47.25
4.52 * .04 .9232 1.6089 48.82 l-Phenyl-l,3-butadiene made by the hydrolysis trans 83 11 The molar refraction calculated from the Lorentzof the cinnamaldehyde-methylmagnesium bromide addition compound in 30% sulfuric acid1 Lorenz equation is 43.85. has been shown to be the pure trans isomer The boiling point, density and refractive index by its quantitative Diels-Alder reaction with are usually greater for the cis form of olefinic maleic anhydride.2 Varying the conditions of hydrocarbons. This is also true of piperylenee2 hydrolysis does not, as previously reported,a The exceptional behavior of the phenylbutadienes give the cis and trans forms but only the trans is noteworthy. is obtained. I n ultraviolet absorption spectra the cis form cis-l-Phenyl-1,3-butadienehas been made by shows a maximum a t 265-269 mp, molar extincultraviolet irradiation of the trans isomer. The tion 184 X lo2, and the trans a t 280 mp, molar cis compound does not react with maleic an- extinction 298 X lo2. An outstanding difference hydride a t room temperature. Irradiation of the in infrared absorption spectra is the 14.20-p band cis compound isomerizes it partially to the trans. for the cis and the 10.56-11 band for the trans The two isomers differ markedly in physical which are unique for each isomer. Neither geometric isomer adds sulfur dioxide properties : to give a cyclic sulfone. (1) Grummitt and Becker, THISJOURNAL, 70, 149 (1948). (2) Robey, Morrell and Wiese, zbid., 63, 627 (1941) and Craig, ibid., 66, 1006 (1943) differentiated cis and trans piperylenes by the greater reactivity of the trans isomer t o maleic anhydride. (3) Muskat and Herrman, ibid.. 63, 252 (1931).
MORLEYCHEMICAL LABORATORY WESTERNRESERVE UNIVERSITY OLIVERGRUMYITT 6, OHIO FRANK J. CHRISTOPH CLEVELAND 13, 1949 RECEIVED OCTOBER
