Nickel-catalyzed cyanation of C—S bond using CO2 and NH3

Abstract

Catalytic cleavage of C—S bonds is an important approach in the construction of functionalized molecules. Herein, we developed the catalytic synthesis of nitriles from thioethers, utilizing CO₂ as the carbon source for the first time. This work addressed the challenge of avoiding toxic cyanides by generating the “CN” group via isocyanate intermediates from CO₂ and NH₃ with the aid of Ni-phosphine catalysts and hydrosilane. A wide range of aryl thioethers were efficiently converted into the corresponding aryl nitriles, demonstrating good functional groups tolerance including fluorine, morpholine, piperazine amide, and cyano group. Additionally, chloride anion played essential roles probably through facilitating the generation of Ni (I) species by promoting Ni—S bond cleavage, thus enhancing the overall reaction efficiency.