Hypervalent Iodine(III) Promoted Direct Synthesis of Imidazo[1,2-a]pyrimidines

An efficient and mild synthesis of imidazo[1,2-a]pyrimidine derivatives has been developed from readily available pyrimidyl arylamines or enamines through a hypervalent iodine-promoted intramolecular C-H bond cycloamination reaction. This protocol allows for the facile construction of biologically active bicyclic imidazo[1,2-alpha]pyrimidine skeletons as well as other imidazo[1,2-alpha]-type fused heterocycles.