Notes on scientific research. 143 



On a new a,fi-ketonic alcohol C 9 Hi O 2 , compare p. 150 of this Report. 



From atractylol, Seisi Takagi 1 ) obtained, by reduction with hydrogen and platinum 

 in glacial acetic acid, dihydroatractylol Ci 5 H 2 8 as a viscid oil, [«] D i20 + 14.9°. 



Aldehydes. 



K. W. Rosenmund and F. Zetsche 2 ), by catalytic dehydrogenation by means of the 

 "copper-quinoline-nitro-body" and of oxygen, obtained from primary aliphatic, aromatic 

 and equally hydrocyclic alcohols the aldehydes, from secondary alcohols the ketones. 

 Tertiary alcohols remain unaffected. The following examples are cited by the authors: — 

 benzophenone from benzhydrol (yield, 92 per cent), "fermentation" valeric aldehyde from 

 "fermentation" amyl alcohol (80 per cent.), acetaldehyde from ethyl alcohol (52 per cent.), 

 propionic aldehyde from propyl alcohol (5 per cent.), isobutyric aldehyde from isobutyl 

 alcohol (75 per cent.), o-chlorobenzaldehyde from o-chlorobenzyl alcohol (86.2 per cent.), 

 fural from furyl alcohol (74 per cent.). The method is particularly suited with the 

 difficultly, or non-volatile, alcohols; with the volatile alcohols, the method offers no 

 advantages compared with the usual processes. 



The method worked out by Rosenmund and Zetsche 3 ) for the catalytic preparation 

 of aldehydes from the corresponding acid chlorides lends itself likewise to the prepa- 

 ration of polyaldehydes, as the authors found in community with Chr. Flutsch*). The 

 following aldehydes were obtained by this method, with an average yield of 75 to 

 85 percent.: — octanedial = suberic dialdehyde (di-semicarbazone, m. p. 183 to 185°; 

 dioxime m. p. 152°); phen-dimethylal-1,3 = isaphthalic dialdehyde, m. p. 88 to 89°; 

 phen-dimethylal-1,4 = ferephthalic dialdehyde, m. p. 116°. (M/iophthalic dialdehyde, 

 however, was unobtainable from the o-phthalic acid chloride, probably the o-acid 

 dichlorides are rearranged to the asymmetric form owing to the palladium chloride 

 formed in the reduction. 



I 

 The following process for preparing aromatic hydroxyaldehydes has been patented 



in the U. K. in favour of the Societe chimique des usines du Rhone 5 ): — Phenols or 



their derivatives are treated at suitable temperatures with formaldehyde in presence 



of a nitroso compound, such as nitrosobenzene, nitrosonaphthalene, or p-nitroso- 



dimethylaniline. If necessary, a condensating agent, e. g., hydrochloric acid, is added. 



When the reaction has passed off the solvent is removed by distillation and the hydroxy 



aldehyde worked up as usual. 



The specification deals with the preparation of vanillin by starting from guajacol, 

 formaldehyde, and j9-nitrosodimethylaniline. In the same manner anisic, protocatechuic, 

 ;>-hydroxybenzoic, and salicylic aldehydes are obtainable. 



Closely related to this process is the method specified by H. Haakh 6 ): — Phenols, 

 or derivatives thereof, are allowed to react with formaldehyde, or bodies splitting off 

 formaldehyde, and aromatic nitroso compounds, e. g., ^-nitrosodimethyl(ethyl)aniline, 

 /v-nitrosophenol, in presence of a condensing medium (hydrochloric acid). By this 

 method, anisic aldehyde may be prepared from anisole, and vanillin from guajacol. 



: ) J&urn. phorm. Hoc. Japan 1921, N° 473. Cf. also p. 47 of this Report. — 4 ) Berl. Berichte 54 (1921), 

 2033. -- ») Cf. Report 1918, 122. — 4 ) Berl. Berichte 54 (1921), 2888. — . B ) Brit. Pat. 161679, April 13, 

 1921 ; cf. also French Pat. 523407, Aug. 18, 1921, and Swiss Pat. 95560, Nov. 1. 1921. — 6 ) Brit. Pat. 157850, 

 Febr. 17, 1921. As per Chem. Zentralbl. 1921, IV. 121. 



