Mechanochemical synthesis of carbene copper complexes for CO2 hydrogenation to formate

This paper reports mechanochemical synthesis of carbene copper complexes for catalytic hydrogenation of CO 2 to formate with H 2 . Significantly improved in catalytic activity was acquired by adding triethoxysilane activator, affording the highest TON up to 5720. Stoichiometric reactions are managed to support the rationality of the pivotal steps in proposed catalytic cycle for the cleavage of H 2 and activation of CO 2 . • Mechanochemical synthesis of carbene copper complexes without any solvents. • Hydrogenation of CO 2 to formate with H 2 catalyzed by carbene copper complexes. • The best TON of 5720 was acquired by using CAAC 1 CuO t Bu as catalyst and triethoxysilane as an activator.