Visible-light-enhanced photocatalytic Sonogashira reaction over silicon carbide supported Pd nanoparticles

Abstract

Sonogashira reaction of aryl halides with terminal alkynes can be realized by a visible-light-driven heterogeneous catalytic route using silicon carbide supported Pd nanoparticles as the catalyst under copper-, and ligand-free conditions. Under the irradiation of visible light, the photo-generated electrons excited in SiC can quickly transfer to Pd nanoparticles through the Mott-Schottky contact, and make them electron-rich. The electrons of Pd particles become energetic by absorbing the energy of visible light, and then transfer to halogen atoms to facilitate the cleavage of carbon-halogen bond in aryl halides. The final carbon-carbon formation is achieved by the substitution reaction and reductive elimination processes.