206 



AROMATIC ALDEHYDES AND KETONES 



[114 A. 



tion with manganese dioxide suspended 

 in water (Schmidt, Germ. Pat. 20909 

 of 1883; Ber. 16,448). 



Benzal chloride gives benzoic alde- 

 hyde on heating with acetic acid in 

 presence of zinc chloride, &c. ( Jacobsen, 

 Ber. 13, 2013; 14, 1425; Germ. Pat. 

 11494 of 1879, and suppl. Pat. 13127 

 of 1880 Ch. Ind. 3, 384 ; 4, 202) ; 

 or with strong sulphuric acid and subse- 

 quent treatment with water (Oppen- 

 heim, Ber. 2, 213) ; or with anhydrous 

 oxalic acid (Anschiitz, Ann. 226, 18). 



Or benzylamine (from benzyl chloride 

 and ammonia ; see under benzyl mustard 

 oil [169 ; H]) gives the oximeof benzoic 

 aldehyde among the products of oxida- 

 tion by monopersulphuric acid (Bam- 

 berger and Scheutz, Ber. 34, 2262). 

 Benzylamine gives the aldehyde by 

 oxidation with sulphuric acid and a di- 

 chromate (De Coniuck and Combe, 

 Comp. Rend. 127, 1222). 



Or benzylaniline (from benzyl chlor- 

 ide and aniline) gives benzaldehyde on 

 oxidation with dichromate and sulphuric 

 aci 1, &c. (Meister, Lucius, and Briining, 

 Eng. Pat. 10689 of 1896); the sul- 

 phonic acid of benzylaniline also gives 

 benzaldehyde when oxidised in alkaline 

 or neutral solution (Ibid. Ch Centr. 

 1897, 2, 1063). Benzylidene deriva- 

 tives are formed as the first products, 

 and the aldehyde results from their 

 hydrolysis in these processes. Di- 

 benzylaniline can be similarly con- 

 verted into benzaldehyde by oxidation 

 (I/jifL Ch. Centr. 1900, 2, 460: for 

 further list of patents by this firm 

 relating to the production of aldehydes 

 from benzylidene compounds see under 

 p-hydroxybenzaldehyde [119 ; E]). 

 Benzylideneaniline gives benzoic alde- 

 hyde by the action of acil chlorides 

 (Garzarolli-Thurnlackh, Ber. 32, 2277). 



Toluene on treatment with chromium 

 oxychloride and decomposition of the 

 product with water gives benzoic alde- 

 hyde (Etard, Ann. Chim. [5] 22, 225). 

 The aldehyde is also among the pro- 

 ducts of the electrolysis of a mixture 

 of toluene, alcohol, and dilute sulphuric 

 acid (Renard, Jahresber. 1881, 352 ; 

 also Merzbacher and Smith, Journ. Am. 

 Ch. Soc. 22, 723; Puls, Ch. Zeit. 25, 



263), and among the products of oxida- 

 tion of toluene by potassium persulphate 

 (Moritz and Wolffenstein, Ber. 32, 433), 

 by manganese peroxide in presence of 

 sulphuric acid (Soc. Chim. d. Usines du 

 Rhone, Germ. Pat. IQI22I of 1897; 

 Ch. Centr. 1899, 1, 959 ; 107722 of 

 1898; Ch. Centr. 1900, 1, 1113; 

 Weiler, Ber. 33, 464), or by nickel or 

 cobalt oxides (Bad. An. Sod. Fab. 

 Germ. Pat. 127388 of 1900; Ch. 

 Centr. 1902, 1, 150). 



Benzene gives benzoic aldehyde when 

 carbon monoxide and hydrogen chloride 

 are passed through the hydrocarbon in 

 the presence of aluminium chloride and 

 cuprous chloride (Farb. vorm. F. Bayer 

 & Co., Germ. Pat, 98706 of 1897 ; 

 Ch. Centr, 1898, 2, 951 : see also 

 Reformatsky, Journ, Russ. Soc. 33, 

 154). According to Kiichler and Buff 

 (Germ. Pat. 126421 of 1899; Ch. 

 Centr. 1901, 2, 1372) this process does 

 not work with aluminium chloride, but 

 gives good results with the bromide or 

 iodide. 



Benzene and chloroform give a small 

 quantity of benzaldehyde among other 

 products by the action of ferric chloride 

 (Meissel, Ber. 32, 2422). 



Or from benzene and hydrogen cyanide 

 [172] by passing the latter gas with 

 hydrogen chloride through the hydro- 

 carbon in presence of aluminium chloride, 

 and decomposing the product with acid 

 (Farb. vorm. F. Bayer & Co., Eng. Pat. 

 19204, Aug. 1897; Journ. Soc. Ch. 

 Ind. 17, 838). 



From benzene, acetic acid, and hydro- 

 gen cyanide [172] through iminobenzoyl- 

 methyl cyanide (benzacetodinitrile) by 

 the action of sodium on a mixture of 

 benzonitrile and acetonitrile in dry ether 

 (Holzwart, Journ. pr. Ch. [2] 39, 242), 

 i 2 -cyanacetophenone by the action of 

 hydrochloric acid on the imino-cyanide 

 (Meyer, Ibid, 243), benzoylacetimino- 

 ethyl ether by the action of alcoholic 

 hydrochloric acid on the cyanoketone 

 (Haller, Bull. Soc. [2] 48, 24), benzoyl- 

 acetic ester by the action of dilute 

 alcohol on benzoylacetiminoethyl ether 

 (Ibid. 25), and then as below under C. 



NOTES : Acetonitrile is obtained from am- 

 monium acetate [Vol. II] through acetamide and 



