Synthesis of new cyanoethyl derivatives from 3-oxotriterpenoids

Abstract

Reaction of 3-oxotriterpenoids and steroids with acrylonitrile in the presence of BnEt₃NCl and 30% KOH in dioxane proceeds with the formation of 2,2-biscyanoethyl derivatives substituted in the α-position to 3-oxo group. In the presence of several α-hydrogen atoms at the 3-oxo group the reaction of cyanoethylation involved the positions C⁴ and C⁵, leading to 2,2,5-tricyanoethyl and 2,4-dicyanoethyl derivatives. The cyanoethylation of tetracyclic compounds occurred with the formation of monocyanoethyl derivatives with an overall increase in the yield.