Trifluoroacetic acid-promoted Michael addition–cyclization reactions of vinylogous carbamates

Abstract

A simple and efficient methodology has been developed for the synthesis of pyrrolobenzoxazine and 3-arylamino coumarin derivatives promoted by trifluoroacetic acid. The initial step in the current protocol involves a Michael addition of the 1,4-benzoxazinone derivatives, a novel class of vinylogous carbamates to the Michael acceptors and subsequent cyclization.