# — 157 — 



ketones. It is probable that in the condensation-products which are 

 originally formed the ethylenic bond is not in the semicyclic position, but 

 occurs within the ring, or the bodies may present a mixture in which 

 the second modification exceeds the first. It may be assumed that ad- 

 dition preceeds condensation, in which case the additive product must 

 possess the formula I shown below, and a compound of this type may 

 as readily be converted into II as in III. 1,3- and 1,4-Methylci/cZohexanone 

 and acetone gave rise to 1,3- and 1,4-methylc^/cZohexene acetone which were 

 reducible by Paal's method into 1,3- and 1,4-methylc^/dohexyl acetone. 



OH 



CH 2 COCH 



i 



J>= CHCOCH 3 \__S~ GH2 C0CH3 



ii in 



In our last October Report, p. 146, we referred to the ketonic acid 

 C12H20O3 which had been prepared by O. Wallach 1 ) from cyclohexyl- 

 hexanone by oxidation with chromic acid in glacial acetic acid, and which 

 he supposed to be a <?-hexahydrobenzoyl-w-valeric acid. Wallach has 

 recently been able to prove the correctness of his supposition 2 ). He 

 split up cz/cZohexylhexanone-^so-oxime by heating in a sealed tube with 

 hydrochloric acid, and thus obtained an amido-acid which, when oxidised 

 with potassium permanganate in faintly alkaline solution, yielded the keto 

 acid C12H20O3. The formation of this ketonic acid from the amido acid 

 proves that the amido acid is 6-c^/dohexyl-e-amido-n-caproic acid and that 

 for the ketonic acid the formula C 6 HiiCO(CH2)4C0 2 H must be regarded 

 as having been established. For from the amide of the ketonic acid 

 Wallach obtained a ketoximic acid C 6 HiiC(CH2)4C0 2 H which was very 



NOH 

 readily rearranged by means of phosphorus pentachloride. In the course 

 of this reaction a compound was formed which was isomeric with the 

 oximic acid used. This compound, when heated in a sealed tube with 



.hydrochloric acid, was split up into q/cZohexylamine and adipic acid. 



ftdence it follows that the conversion-product of ketoximic acid must have 

 the formula C 6 HiiNHCO(CH2)4C0 2 H: that the isomerisation must have 

 proceeded as follows: C 6 H 11 C(CH 2 ) 4 C0 2 H— ^C 6 H 11 NHCO(CH 2 )4C02H; 



HON 



and that the fundamental ketonic acid can only have possessed the structure 

 C 6 H 11 CO(CH 2 )4C02H. 



x ) Liebigs Annalen 381 (1911), 102. 

 2 ) Ibidem 389 (1912), 169. 



