Selective Reduction of Nitroarenes with Silanes Catalyzed by Nickel N‐Heterocyclic Carbene Complexes

An efficient catalytic system for the reduction of nitroarenes to amines was developed using a well‐defined nickel–NHC (N‐heterocyclic carbene) complex as catalyst and phenylsilane as reducing agent. The excellent activity of the catalyst provides access to anilines containing a wide array of reactive functionalities at 20 °C, and without using any base or additive. Notably, the catalytic system allows the reduction of 5,10,15,20‐tetra‐(nitrophenyl)porphyrin (TNPP) and CuII β‐nitroporphyrin to the corresponding aminoporphyrins. Half‐sandwich catalysts: Well‐defined NiII–NHC (N‐heterocyclic carbene) complexes were used as catalysts for the reduction of nitroarenes to amines with silanes at 20 °C. Excellent yields and chemoselectivities were obtained for a wide range of nitroarenes, including nitroporphyrines.