Highly selective custom reduction products for hydrogenation of CO2-derived urea derivatives or carbamates

Abstract

Catalytic hydrogenation of CO₂-derived urea derivatives or carbamates provides an indirect and efficient solution for the chemical transformation of CO₂ under mild conditions, avoiding the high temperatures and pressure required for direct catalysis to overcome the thermodynamic energy barrier and the low yield of the targeted product. However, the reported catalyst systems focus mainly on the preparation of one specific product, especially switching the product type requiring external acid/base additives, which limits the development of this protocol. Here, we report a promising route for the hierarchical reduction of CO₂-derived urea derivatives or carbamates using an Ir-based PNP pincer catalyst system, enabling the selective production of specific chemicals (methanol, formamides, N-methylamines, or N,N-dimethylamines) for the first time by altering reaction conditions, especially the reaction temperature. This work demonstrates the significant potential of urea derivatives or carbamates hydrogenation for indirect conversion of CO₂ to valuable chemicals and fuels, provides a facile temperature-dependent product-switching strategy in one catalytic system.