Visible-light-driven carbonylation reaction over palladium supported on spherical-like graphitic carbon nitride

Exploring sustainable catalysts for the transition-metal-catalyzed carbonylation and acknowledging the corresponding interior mechanism are of great interest. Herein, palladium supported spherical-like graphitic carbon nitride catalyst (Pd@s-CN) was prepared through a microwave-assisted approach, where s-CN with larger surface area was synthesized via an exfoliation and refluxing method. The spherical-like structure of s-CN can offer abundant space preventing the agglomeration of Pd and creating more active sites for carbonylation reaction. Notably, with iodobenzene as the substrate, Pd@s-CN achieved 92% yield of benzoic acid, and its performance was better than that of PdCl 2 and Pd/C catalysts. The effects of thermal, light source and catalyst structure were investigated. Ultimately, the reaction mechanism of photocatalytic carbonylation was proposed. This environmentally friendly photocatalytic carbonylation method is expected to provide a new idea for carbonylation and other related organic synthesis reactions.