Brønsted acid-catalyzed Reactions of Unprotected N-heterocycles with Aryl/Aryl Diazoalkanes

Abstract

The chemoselective C−H functionalization of unprotected N-heterocycles is a challenging task in organic synthesis. Herein, we report on a Brønsted-acid catalyzed reaction of aryl/aryl diazoalkanes with unprotected N-heterocycles to selectively allow for C−H functionalization at the C3-position under mild reaction conditions and short reaction time without the need of protecting groups. The general applicability of this method was further expanded towards protected indole and unprotected pyrrole heterocycles.