10.1039/c5nj02378e
The study presents a novel one-pot method for the catalytic cyclopropanation of various alkenes with unsubstituted hydrazones. The process utilizes iodosobenzene as an oxidant to convert hydrazones into diazo compounds, which are then cyclopropanated in the presence of a nickel(II) catalyst, Ni(OH)2. This method allows for the efficient generation of cyclopropane products under mild conditions (80°C) within a short time frame (5 minutes to 4 hours) and with moderate to good yields (42–91%). The protocol is applicable to a wide range of substrates, including aryl alkenes with different electronic effects, aliphatic alkenes with halogen functional groups, and alkyl acrylates. The study also explores the reaction mechanism and provides a promising approach to synthesizing cyclopropane compounds, which are prevalent in natural products and have significant value in pharmaceutical chemistry.