Mechanistic insight into the ligand-controlled regioselective hydrocarboxylation of aryl olefins with palladium catalyst: A computational study

Abstract

The density functional theory (DFT) calculations were employed to investigate the reaction mechanisms of Pd-catalyzed hydrocarboxylation of styrene with different ligands. The regioselectivity is controlled by the employed ligand. By using the ligand of tris[4-(trifluoromethyl)phenyl]phosphine, the electron-deficient p-CF3 group would cause the branched 2-arylpropionic acid to be the major product. The observed regioselectivity could be attributed to the electronic effects. In the presence of tris(2-methoxyphenyl)phosphine ligand, the bulky o-OMe group would reverse the reaction to produce linear 3-arylpropionic acid. Moreover, the existed CH···Π interaction could also account for the regioselectivity.