Ce(SO4)2⋅4H2O as a highly efficient catalyst for the one-pot synthesis of tri- and tetra-substituted imidazoles under solvent-free conditions

A solvent-free one-pot convenient synthetic route for rapid synthesis of various tri- and tetra-substituted imidazole derivatives has been developed using Ce(SO4)2⋅4H2O as an efficient catalyst with high catalytic activity in the three-component reaction (3-CR) of benzil or benzoin, aromatic aldehydes, and ammonium acetate, as well as in the four-component reaction (4-CR) of benzil, aryl aldehydes, benzyl amine, and ammonium acetate. These protocols provide an excellent and versatile synthetic scaffold for construct of various heterocycles containing imidazole as a core frame.