A copper-catalyzed multi-component reaction accessing fused imidazo-heterocycles via C-H functionalizationElectronic supplementary information (ESI) available. See DOI: 10.1039/c5ra09025c

An efficient synthesis of fused imidazo-heterocycles is described using Cu(OTf) 2 in [bmim]BF 4 by the multi-component reaction of pyridin-2(1 H )-one or thiazol/benzo[ d ]thiazol-2(3 H )-ones with O -tosylhydroxyl amine and acetophenones under microwave irradiation. The present method is very rapid and the product formation occurs via a C-H functionalization/tandem addition-cyclization process. The ionic liquid containing copper triflate is recovered and reused four times. An efficient synthesis of fused imidazo-heterocycles is described using Cu(OTf) 2 in [bmim]BF 4 by the multi-component reaction of pyridin-2(1 H )-one or thiazol/benzo[ d ]thiazol-2(3 H )-ones with O -tosylhydroxyl amine and acetophenones under microwave irradiation.