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

ABSTRACT: 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 (MnO_x@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.

SUBMITTER: Wang L

PROVIDER: S-EPMC5440663 | biostudies-literature | 2017 May

REPOSITORIES: biostudies-literature

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

Wang Liang L Wang Guoxiong G Zhang Jian J Bian Chaoqun C Meng Xiangju X Xiao Feng-Shou FS

Nature communications 20170515

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 (MnO<sub>x</sub>@S-1), which ...[more]

PMID: 28504259

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