Graphitic Carbon Nitride (g-C3 N4 ) Supported Palladium Species: An Efficient Heterogeneous Photocatalyst Surpassing Homogeneous Thermal Heating Systems for Suzuki Coupling.

Abstract

Suzuki coupling is of paramount importance in C-C coupling reactions. However, Suzuki coupling reactions are generally catalyzed by homogeneous catalysts under thermal heating, which results in difficulties in the catalyst separation and consumes a relatively large amount of energy. g-C3 N4 /Pd has been successfully prepared for photocatalytic Suzuki coupling reactions. The g-C3 N4 /Pd is prepared through the reduction of a Pd source in the presence of g-C3 N4 . The Pd is found to exist as Pd nanoparticles and Pd(II) species on g-C3 N4 . Owing to the good light absorption of g-C3 N4 and the excellent catalytic activity of the Pd species, the g-C3 N4 /Pd shows an excellent photocatalytic performance in Suzuki coupling reactions with a TOF of 47.3 h-1 , which is almost twice that of a commercial homogeneous catalyst Pd(PPh3 )4 , under thermal heating. Moreover, g-C3 N4 /Pd displays very good recyclability and wide applicability for Suzuki coupling reactions. Our findings provide a green and sustainable method for the catalysis of Suzuki coupling reactions.