Cyrene Dimethyl Acetal: Potential Alternative Solvent for Pd‐Catalyzed Homogeneous Aminocarbonylation of Iodo(hetero)arene Compounds

Two potential biomass-derived Cyrene-based reaction media, i.e., Cyrene dimethyl and diethyl acetals, were synthesized and tested as potential polar aprotic alternatives to fossil-based common N,N-dimethylformamide in aminocarbonylation protocols. New solvents were first characterized by their temperature-dependent physicochemical properties, including vapor pressure, density, viscosity, heat capacity, and surface tension. Based on their characteristics, Cyrene dimethyl acetal (CyDiOMe) was selected and used in the Pd-catalyzed aminocarbonylation of iodobenzene and morpholine as a model reaction for optimization. Under optimized conditions, a wide substrate scope was demonstrated for the synthesis of various carboxamides with high conversion (up to 95%) and selectivity in a short reaction time. Twenty-nine products were isolated, proving the applicability of CyDiOMe in Pd-catalyzed aminocarbonylation.