Diethyl malonate as leaving group: Facile synthesis of some 1,3,4-benzotriazepines and benzotriazepinones

Abstract

Reaction between 2-(2′,2′-bis-carboethoxyvinylamino)-benzophenones, resulting from the condensation of 2-aminobenzophenones with diethyl ethoxymethylenemalonate, and hydrazine hydrate yields 5-hydroxy-5-phenyl-1,3,4-3H-4,5-dihydrobenzotriazepines or their double bond isomers. These products on acetylation afford O,N,N-triacetates, which on treatment with ammonia are transformed into 4-phenylquinazolines. Structure proof of these substances is reported.