Reactions of 'Cage' Dione with Primary Amines;Revision of an Earlier Report

摘要

Reactions of pentacyclo[5.4.0.0~(2,6).0~(3,10).0~(5,9)]undecane-8,11-dione(1,'cage' dione)with primary amines(i.e.benzylamine,aniline,methylamine and 2-aminoethanol)leading to the adducts 4a-d in good yields are described.In all cases the transannular cyclization process was observed and oxa-bridged products 4a-d were obtained.Isolated compounds were identified as hemiacetals or their internal salts.The type of the formed product is dependent on basicity of the used amines.Subsequent dehydration of the initially obtained adducts in boiling benzene led to monoimines 3a-d.