Well-defined Cp*Co(III)-catalyzed Hydrogenation of Carbonates and Polycarbonates

We herein report the catalytic hydrogenation of carbonates and polycarbonates into their corresponding diols/alcohols using well-defined, air-stable, high-valent cobalt complexes. Several novel Cp*Co(III) complexes bearing N,O-chelation were isolated for the first time and structurally characterized by various spectroscopic techniques including single crystal X-ray crystallography. These novel Co(III) complexes have shown excellent catalytic activity to produce value added diols/alcohols from carbonate and polycarbonates through hydrogenation using molecular hydrogen as sole reductant or (PrOH)-Pr-i as transfer hydrogenation source. To demonstrate the developed methodology's practical applicability, we have recycled the bisphenol A monomer from compact disc (CD) through hydrogenation under the established reaction conditions using phosphine-free, earth-abundant, air- and moisture-stable high-valent cobalt catalysts.

Automated summary

By utilizing high-valent cobalt complexes, carbonates and polycarbonates have been successfully catalytically hydrogenated into diols/alcohols, with the synthesis of novel Cp*Co(III) complexes. This method demonstrates excellent catalytic activity and the ability to recycle bisphenol A monomer from waste CDs.