Synthesis of Pyrido[2, 3-a]phenoxazines and Pyrido[2, 3-a] phenothiazines via Successive SNAr Processes

摘要

An efficient method was developed for the synthesis of novel pyrido[2, 3-a]phenoxazines and phenothiazines. The base-promoted reaction of 8-chloro-5,7-dinitroquinoline with binucleophiles (o-aminophenols and o-aminothiophenols) results in substitution of the chlorine atom followed by replacement of the nitro group. In case of aminothiophenols the products of in situ Smiles rearrangement were isolated.