216 



AROMATIC ALDEHYDES AND KETONES [119 A-E. 



and oxalic acid [Vol. II] through the 

 following stages : Picric acid (from 

 phenol) is converted into picrylphenol 

 by the action of picryl chloride on 

 potassium phenate. Oxalic acid is con- 

 verted into ethyl oxalate, and the latter 

 into ethyloxalyl chloride [120 ; B], 

 which combines with picrylphenol in 

 the presence of aluminium chloride to 

 form picryl-p-hydroxyphenylglyoxylic 

 ester : 



(NO,) 3 C 6 H, . O . C 6 H 4 . CO . CO 2 C,H 5 . 



The latter on hydrolysis with alcoholic 

 potash gives p-hydroxyphenylglyoxylic 

 acid, and this on distillation in vacua, 

 or on heating with dimethylaniline, 

 yields (with p-hydroxybenzoic acid) p- 

 hydroxybenzoic aldehyde (Bouveault, 

 Bull. Soc. [3] 17, 947). 



NOTE : For technical production from 

 phenol by condensation with/orwu'c aldehyde [91] 

 and p-toluylhydroxylamine-m-sulphonic acid 

 (from p-nitrotoluene-m-sulphonic acid), and 

 decomposition of the condensation product by 

 heating with dilute acids or alkalis, see Geigy's 

 Germ. Pats. 103578 of 1898 ; Ch. Centr. 1899, 

 1, 926 ; 105103 of 1898 ; Ch. Centr. 1900, 1, 

 239 J i579 8 of l8 9 8 5 Ibid - 523- 



[B.] Cinnamic acid [Vol. II] or its 

 ester on nitration gives (with ortho-) 

 paranitrocinnamic acid or ester (Mit- 

 scherlich, Journ. pr. Ch. 22, 192; Ann. 

 Chim. [3] 4, 73; Kopp, Comp. Bend. 

 53, 634 ; Beilstein and Kuhlberg, Ann. 

 163, 1 26 ; Tiemann and Opermann, 

 Ber. 13, 2059; Miiller, Ann. 212, 124; 

 Drewsen, Ibid. 150). The p-nitro-acid 

 (or ester) on oxidation gives p-nitro- 

 benzoic aldehyde (Baeyer, Ber. 14, 2317 : 

 see also Easier, Ber. 16, 2714), which 

 combines with hydroxylamine to form 

 an oxime (Gabriel and Herzberg, Ber. 

 16, 2000), and this reduces to the oxime 

 of p-aminobenzoic aldehyde (Ibid. 2001), 

 which, by the action of acids, yields the 

 p-amino-aldehyde (Ibid. 2002). The 

 latter gives the hydroxy-aldehyde by 

 the diazo-method (Walther and Bret- 

 schneider, Journ. pr. Ch. [2] 57, 538). 



Or cinnamic acid can be combined 

 with bromine or with hypobromous acid, 

 and the product converted into co-brom- 

 styrene by heating with water (Glaser, 

 Ann. 154, 1 68). The bromstyrene on 

 nitration gives (with another isomeride 



and p-nitrobenzoic acid) a-p-nitrophenyl- 

 /3-bromnitroethylene, NO 2 . C 6 H 4 . CH : 

 CBrNO 2 , and this, on boiling with 

 water, yields p-nitrobenzoic aldehyde 

 among other products (Fliirscheim, 

 Journ. pr. Ch. [2] 66, 16). 



[C.] Styrene [7] by the action of 

 nitric or nitrous acid gives i^-nitrosty- 

 rene = phenylnitroethylene (Simon, 

 Ann. 31, 269; Blyth and Hofmann, 

 Ann. 53, 297 ; Priebs, Ann. 225, 328), 

 which, by further nitration, yields 4 : i 2 - 

 dinitrostyrene (Priebs, loc. cit. 348). 

 The latter, on heating with strong sul- 

 phuric acid at 110, gives p-nitrobenzoic 

 aldehyde (Friedlander and Mahly, Ann. 

 229, 213). Subsequent steps as above. 



[D.] From lenzoic aldehyde [114] and 

 methyl alcohol [13] by the action of 

 nitromethane on the aldehyde at 160 

 in presence of zinc chloride (Priebs, 

 Ann. 225, 321), which gives i 2 -nitro- 

 styrene. Subsequent steps through 

 dinitrostyrene, p-nitrobenzoic aldehyde, 

 &c., as above. 



NOTE : Nitromethane is prepared from 

 methyl iodide and silver nitrite (Bewad, Journ. 

 Russ. Soc. 24, 126 ; Meyer, Ann. 171, 32). 

 Formed also from potassium chloracetate and 

 potassium nitrite (Kolbe, Journ. pr. Ch. [2] 5, 

 427; Preibisch, Ibid. 8, 310: see also under 

 glycerol [48 ; K ; L], and hydrogen cyanide 

 [172 ; J ; Y]). 



Or from benzoic aldehyde and succinic 

 acid [Vol. II] through phenylisocrotonic 

 acid by heating the aldehyde with suc- 

 cinic anhydride and sodium succinate 

 (Perkin, Journ. Ch. Soc. 31, 394), or 

 with sodium succinate and acetic anhy- 

 dride (Jayne, Ann. 216, 100; Leoni, 

 Ann. 256, 64). Phenylisocrotonic acid 

 by the action of fuming nitric acid 

 gives i 2 -nitrostyrene (Erdmann, Ber. 17, 

 412), which can be treated as above. 



[E.] From benzene [6 ; I, &c.] or 

 toluene [54] by various processes : 



From benzene and formic aldehyde 

 [9l] through phenylhydroxylamine 

 (Bamberger, Ber. 27, 1347; 1548; 

 Wohl, Ibid. 1432), which condenses 

 with the aldehyde to form a polymeric 

 anhydro-derivative of p-hydroxylamine- 

 benzyl alcohol. The diazo-derivative 

 of the latter, on heating with water, 

 gives p-hydroxybenzoic aldehyde (Kalle 



