Mechanism and Origin of Nickel-Catalyzed Decarbonylative Construction of C(sp2)–C(sp3) Bonds from Carboxylic Acids and Their Derivatives

Nickel-catalyzed arylation of carboxylic acids provides a ligand-controlled chemoselectivity-switchable method for the construction of C(sp²)–C(sp³) bonds. Here, we employed density functional theory to provide a detailed understanding of the mechanism and origin of nickel-catalyzed ligand-controlled carbonyl transformation. This reaction generates decarbonylation products through oxidative addition, activation of C–C bonds, decarbonylation, binding of alkyl radicals with Ni(III) complexes, and final reduction elimination step. The activation of C–C bonds in aromatic carboxylate esters is more favorable than C–O bond activation because of the interaction between the nickel catalyst and the π orbitals of the substrate’s aromatic moiety during C–C bond activation. The induction effect of the ligand and the carbonyl group together determines the transfer tendency of the carbonyl group.