A general route for synthesis of N-aryl phenoxazines via copper(i)-catalyzed N-, N-, and O-arylations of 2-aminophenols

Abstract

A novel copper(I)-catalyzed tandem reaction of N- and O-arylations of 2-[N-(2-chlorophenyl)amino]phenols was developed, by which a series of structurally novel N-aryl phenoxazines were synthesized efficiently. This success owes much to the discovery of highly efficient homogeneous copper(I)-catalyzed intramolecular O-arylation of chlorobenzenes under ligand-free-like conditions. Since 2-[N-(2-chlorophenyl)amino]phenols were prepared also by copper(I)-catalyzed N-arylation of 2-aminophenols, thus a general route for efficient synthesis of N-aryl phenoxazines was established via copper(I)-catalyzed N-, N-, and O-arylations of 2-aminophenols in two steps.