Organic–inorganic hybrid material, dichloro N,N'-(1,2-phenylene)bis(2-aminobenzamide) cobalt(II)@Al-SBA-15: an environment friendly catalyst for the synthesis of 3-benzoxazol-2-yl-chromen-2-ones

Abstract

A new organic-inorganic hybrid material, CoCl2N,N'-(1,2-phenylene)bis(2-aminobenzamide)@Al-SBA-15, was synthesized by modification of Al-SBA-15 with (3-chloropropyl) trimethoxysilane (CPTMS), then the ligand was covalently attached to CPTMS@Al-SBA-15 and finally addition of CoCl2 to form the complex. The mesoporous CoCl2NN'PhBIA@Al-SBA-15 was an efficient catalyst in the preparation of 3-benzoxazol-2-yl-chromen-2-one derivatives through reaction of different coumarin-3-carboxylates and 2-aminophenol derivatives. The nanocatalyst increased rate and facility of the aforementioned reaction and had influence in the green synthesis of different 3-benzoxazol-2-yl-2H-chromen-2-one derivatives. The nanocatalyst was characterized by N2 adsorption–desorption, Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), powder X-ray diffraction (XRD), and energy dispersive spectroscopy (EDS). Some advantages of this procedure are mild reaction condition, high yields of 3-benzoxazol-2-yl-2H-chromen-2-one, short reaction times, environmentally benign, recoverability of the catalyst and reusability without significant loss of its catalytic performance.