— 147 — 



The two isomeric trimethylcyclohexanones, methyl- 1 -dimethyl -3, 3- 

 cyclohexanone - 5 (dihydroisophorone) x ) , and methyl - 1 - dimethyl -3,3- 

 cyclohexanone - 6 , readily form oximes of the m. p. 84 to 85 , and 

 108 to 109 respectively, from each of which by treatment with 

 dilute sulphuric acid two isomeric isoximes are obtained. The higher- 

 melting, more difficultly soluble a - modifications of the isoximes melt 

 at in to 112 and 113 to 11 6° respectively, the ^-modifications at 

 at 82 to 84 and 106 to 108 respectively. 



In agreement with previous observations made with 1-menthone 2 ), 

 Wallach also succeeded in producing from 1,3-methylcyclohexanone, 

 by reduction of the /S-oxime, /?-methylcyclohexylamine. The use of 

 the ammonium formiate method 3 ) for this reaction resulted, in addition 

 to the primary, also in much of the secondary base. But it could 

 now be proved that this consists of a mixture of physically isomeric 

 bases, of which two were isolated by fractionated precipitation with 

 formic acid. a-Cyclodimethylhexylamine forms a hydrate which, with 

 loss of water, melts at 46 to 48 ; the /?-forms hows no tendency to 

 crystallise with water, but remains liquid. From the a -base, the following 

 derivatives were produced: 1. The benzoyl compound (C 7 H 18 ) 2 N 

 • COC 6 H 5 , m. p. 141 ; Md — 34,646° (in ethereal solution). 2. The 

 nitroso compound (C 7 H 13 ) 2 : N • NO, m. p. 83 to 84°; [a] D — 34° (in 

 ethereal solution). 3. The phenyl carbamide, m. p. 174 to 176°. 

 The /5-base gave the following derivatives; 1. The benzoyl com- 

 pound, m. p. 151°; Md — 11,877° (in alcoholic solution). 2. The 

 nitroso compound, which could not be obtained in a well-crystallised 

 form, m. p. between 62 and 70°, rotation lower than in the a-compound. 

 3. The phenyl carbamide, m. p. 137 to 138°, has a more feeble 

 rotation than the derivative of the a-base. The hydrochloride of the 

 a-base (m. p. 285°) is separated off more quickly than that of the /?-base 

 (m. p. 211°); nitrate and nitrite dissolve with difficulty and are fairly 

 stable. 



By the action of chlorine on cyclohexanone there is obtained, 

 according to E. Bouveault aud E. Chereau 4 ), a-chlorocyclohexanone. 

 But in addition to this, condensation -products are formed, owing to 

 the action of the hydrochloric acid formed. In order to prevent the 

 formation of free hydrochloric acid, the chlorination is carried out in 

 the presence of calcium carbonate in water, and the cyclohexanol 

 is chlorinated instead of the cyclohexanone. Chlorocyclohexanone 

 boils at 82 to 83° (10 mm. pressure) and melts at 23°. The chlorine 



') Comp. Report April 1903, 93. 



2 ) Liebig's Annalen 300 (1898), 278; Report October 1898, 49. 



3 ) Comp. Report April 1906, 134. 



4 ) Compt. rend. 142 (1906), 1086. 



