Products from cyanoethylation of 2-octanone

Abstract

2-Octanone has been cyanoethylated with solid KOH as catalyst, in dimethoxyethane (DME) as reaction solvent, and with KOH solution in Zert-butyl alcohol; both mono-and dicyanoethylated products have been examined. No product of cyanoethylatian in the terminal position (on methyl) could be detected. In DME as solvent, there were obtained 3-03-cyanoethyl)-2-octanone (3) and a small amount of 3,3-bis(/3-cyanoethyl)-2octanone (4), but the principal product was 5 resulting from cyclization of 4. In feri-butyl alcohol as solvent, under a variety of conditions, none of 4 could be isolated, only 3 and 5. Mass spectrometry was of significance in establishing the structure of 5, and interesting fragmentation patterns were observed. Acid-catalyzed hydrolysis of cyclic product 5 yielded none of the expected diketone, only an acidic product which proved to be the keto diacid which would result from hydrolysis of the open-chain keto dinitrile 4. Acid-catalyzed methanolysis of 5 yielded an initial product whose structure was established as the hemiketal (9) of the keto nitrile which would result from hydrolysis of the imino group in 5. This structure exhibits two hydroxyl absorptions and two

Cyclization of Cyanoethylated Ketones as a Route to 6‐Substituted Indole Derivatives

“…In 1972, Cason et al . reported incorrectly that base‐induced condensation of 3,3‐biscyanoethylated octane‐2‐one will give rise to 4a , that is, a Thorpe cyclization, which in principle should be evident from work reported by Colonge and by Pfleiderer . In fact, condensations leading to 3‐aminocyclohex‐2‐enones 5 will invariably occur.…”