Chlorine-free catalysis for the synthesis of dialkyl carbonate via oxidative carbonylation of alcohols

With the global phase-out of the phosgenation processes, oxidative carbonylation of alcohols to synthesize short-chain dialkyl carbonates (especially DMC, DEC) is considered as a promising route under the guidance of “green chemistry." Despite the good initial performance of chlorine-containing catalyst, including CuCl, CuCl₂, PdCl₂, CuCl₂-PdCl₂, etc., the loss of chlorine during reaction results in the catalyst deactivation, equipment corrosion, and environmental problems. The chapter is to review the progress in oxidative carbonylation of alcohols promoted by chlorine-free catalysts. The catalyst development and process improvement as well as mechanistic understanding are discussed.