Controllable cyanation of carbon-hydrogen bonds by zeolite crystals over manganese oxide catalyst

The synthesis of organic nitriles without using toxic cyanides is in great demand but challenging to make. Here we report an environmentally benign and cost-efficient synthesis of nitriles from the direct oxidative cyanation of primary carbon-hydrogen bonds with easily available molecular oxygen and urea. The key to this success is to design and synthesize manganese oxide catalysts fixed inside zeolite crystals, forming a manganese oxide catalyst with zeolite sheath (MnOx@S-1), which exhibits high selectivity for producing nitriles by efficiently facilitating the oxidative cyanation reaction and hindering the side hydration reaction. The work delineates a sustainable strategy for synthesizing nitriles while avoiding conventional toxic cyanide, which might open a new avenue for selective transformation of carbon-hydrogen bonds.
Sustainable strategies for nitrile synthesis are needed. Here, the authors report an environmentally benign, selective heterogeneous catalyst for the synthesis of nitriles by the oxidative cyanation of carbon and hydrogen (C-H) bonds, which comprises nanoscale manganese oxide catalysts fixed inside a zeolite crystal.