114 C-R] 



BENZOIC ALDEHYDE 



209 



may be heated with aniline, and the 

 anilide hydrolysed by heating- with acid 

 (Fab. Prod. Chim. Thann & Mul- 

 house, Germ. Pat. 94018 of 1896; Ch. 

 Centr. 1897, 2, 1166: see also Bou- 

 veault, Bull. Soc. [3] 17, 363). 



Or from benzoic acid and ethyl alcohol 

 and acetic acid through benzoylacetic 

 ester [Vol. II] by the action of sodium 

 ethylate on a mixture of ethyl benzoate 

 and acetic ester (Claisen and Lowman, 

 Ber. 20, 653), and reduction of the 

 benzoylacetic ester to phenyl-/3-lactic 

 acid by sodium amalgam (W. H. Perkin, 

 junr., Trans. Ch. Soc. 47, 254). The 

 latter acid gives benzoic aldehyde on 

 electrolysis of a dilute solution of the 

 potassium salt (v. Miller, Hofer, and 

 Moog, Ber. 27, 469). 



From benzoic acid and acetoacetic ester 

 [Vol. II] through benzoylacetoacetic 

 ester (Bonne, Ann. 187, i ; Fischer and 

 Billow, Ber. 18, 2131 ; Nef, Ann. 266, 

 99), the sodium derivative of which is 

 decomposed by aqueous ammonia with 

 the formation of benzoylacetic ester 

 (Claisen, Ann. 291, 71). From the ester 

 through phenyl-/3-lactic acid as above. 



Benzoic acid is converted into benzo- 

 nitrile by dehydrating the ammonium 

 salt by heat or dehydrating agents 

 (Fehling, Ann. 49, 91 ; Laurent and 

 Gerhardt, Jahresber. 1849, 327 ; Hof- 

 mann and Buckton, Ann. 100, 155 ; 

 Henke, Ann. 106, 276 ; Wohler, Ann. 

 192, 362 ; Anschiitz and Schultz, Ann. 

 196,48; Henry, Ber. 2, 307). Benzo- 

 nitrile and acetonitrile givebenzaldehyde 

 through iminobenzoylmethyl cyanide, 

 1 2 -cyanacetophenone, benzoy lacetimino- 

 ethyl ether, beuzoylacetic ester (see 

 under A), and then through phenyl-/3- 

 lactic acid as above. 



NOTE : For further references to the pro- 

 duction of benzonitrile from benzoic acid see 

 under benzyl mustard oil [169 ; A]. For 

 syntheses of benzonitrile from benzene see the 

 note under A above. 



Or benzonitrile and ethyl alcohol com- 

 bine in presence of hydrogen chloride 

 to form benzimidoethyl ether (Pinner, 

 Ber. 16, 353 : general synthesis). The 

 ether on reduction with sodium amalgam 

 in acid solution gives benzoic aldehyde 

 (Henle, Ber. 35, 3041). 



Or from benzoic acid and methyl 

 alcohol by the interaction of benzoyl 

 chloride and zinc methyl (Popoff, Ber. 

 4, 720), and treatment of the aceto- 

 phenone so produced as under G-. 



Benzoic acid and hydrazine interact 

 with the formation of benzhydrazide, 

 and this in presence of alkali condenses 

 to benzalbenzoylhydrazine. The latter 

 is decomposed by dilute acids into ben- 

 zoic acid and aldehyde and hydrazine 

 (Curtius, Ber. 33, 2559). 



[D.] Phenylacetic acid [Vol. II] gives 

 a trace of benzoic aldehyde on electroly- 

 sis of an acidified solution of the potas- 

 sium salt (Petersen, Bull. Acad. Roy. 

 Dane. 1897 ; Ch. Centr. 1897, 2, 520). 

 Benzoic aldehyde is also among the pro- 

 ducts of oxidation of phenylacetic acid 

 by dilute sulphuric acid and manganese 

 dioxide. 



Phenylacetic acid gives dibenzyl ke- 

 tone on distillation of its calcium salt 

 (Popoff, Ber. 6, 560; Young-, Trans. 

 Ch. Soc. 59, 623). Benzoic aldehyde is 

 among the products of the photochemical 

 oxidation of the ketone (Emily Fortey, 

 Trans. Ch. Soc. 75, 871). 



[E.] From cinnamic acid [Vol. II] 

 through phenyl-a-chlor-/3-lactic acid by 

 combination with hypochlorous acid 

 (Glaser, Ann. 147, 79), phenyl-/3-lactic 

 acid by reducing the chloro-acid with 

 sodium amalgam (Ibid. 86), and then as 

 above under C. 



Or the chloro-acid, on treatment with 

 alcoholic potash, gives /3-phenyloxyacry- 

 lic = phenylglycidic acid (Glaser, Ann. 

 147, 98), and this yields phenyl-/3- lactic 

 acid on reduction with sodium amalgam 

 (Plochl, Ber. 16, 2823). 



Or cinnamic acid can be combined 

 with hydrogen bromide to form i^brom- 

 hydrocinnamic = phenyl - ft - brompro- 

 pionic acid (Fittig and Binder, Ann. 

 195, 132; Anschiitz and Kinnicutt, 

 Ber. 11, 1221). The latter gives phenyl- 

 /3-lactic acid on boiling with water (F. 

 and B. loc. cit. 138). 



Or cinnamic ester can be brominated 

 so as to give phenyl-a/3-dibrompropionic 

 = a/3-dibromhydrocinnamic ester, and 

 this, by the action of alcoholic potash, 

 gives phenylpropiolic acid(W. H. Perkin, 

 junr., Trans. Ch. Soc. 45, 172 ; Lieber- 



