Oxidative C5-H Amination of Imidazo[1,2-a]pyrimidines via Iodine Catalysis

Abstract

An iodine-catalyzed oxidative C—H amination of imidazo[1,2-𝑎]pyrimidine at C5 position with secondary cyclic amines using tert-butyl hydroperoxide as an oxidant under an open atmosphere at 60 °C has been accomplished. This simple protocol features metal-free reaction conditions, operational simplicity, and a broad substrate scope with high tolerance for various functional groups. Mechanistic studies suggest an anionic pathway for the regioselective amination reaction, proceeding through the in situ formation of an active 𝑁-iodoamine intermediate.