Directed Dilithiation of Diaryl Compounds: Preparation of Tricyclic Pharmaceuticals Based on the Dibenzoheteroazepine Skeleton

Abstract

A facile synthesis of pharmacologically important dibenzo [b,fl[1,4]heteroazepine based tricyclic compounds is reported. Reaction of diaryl compounds such as o-amino-diphenyl ether and o-amino-diphenyl sulfone with n-butyllithium yielded the C,A/-dilithio-diaryl species in excellent yields. These dilithio intermediates were reacted with appropriate ester moieties to synthesize tricyclic compounds based on the dibenzo[b,/][1,4]heteroazepine framework.