Aldol reactions of γ‐ and ϵ‐methylene in 5‐membered heteroaromatic compounds

초록

5‐Methyl‐2‐thiophenecarboxaldehyde (1a) and 3‐methyl‐2‐thiophenecarboxaldehyde (6) underwent intermolecular aldol reactions in which the methyl group behaved as active methylene in the presence of potassium cyanide. 5‐Methylfurfural (1b) gave only 5,5′‐dimethylfuroin in the presence of potassium cyanide. But 1b formed an intermolecular aldol reaction product when sodium hydroxide was used. Copyright © 1995 Journal of Heterocyclic Chemistry