Metal–Organic Framework MIL-101(Cr) as an Efficient Heterogeneous Catalyst for Clean Synthesis of Benzoazoles

A metal–organic framework [MIL-101­(Cr)] was used as an efficient heterogeneous catalyst in the synthesis of benzoazoles (benzimidazole, benzothiazole, and benzoxazole), and quantitative conversion of products were obtained under optimized reaction conditions. The catalyst could be simply extracted from the reaction mixture, providing an efficient and clean synthetic methodology for the synthesis of benzoazoles. The MIL-101­(Cr) catalyst could be reused without a remarkable decrease in its catalytic efficiency.