What is the difference between mono- and biphosphine ligands? Revealing the chemoselectivity in Pd-catalysed carbenation of bromonaphthalene

Abstract

Ligand-controlled chemoselectivity is an important topic in organometallic chemistry. In this work, DFT calculations were used to reveal the chemoselectivity of a Pd-catalysed three-component dearomative carbenation of bromonaphthalene with diazo compounds and allylborates. When a monophosphine ligand was used, ligand exchange with a diazo compound was favored by the release of a phosphine ligand. Therefore, a three-component coupling reaction could occur. However, when a biphosphine ligand was used, ligand exchange between the phosphine and the diazo compounds was difficult. Therefore, the Suzuki–Miyaura coupling product was observed in this case, without the participation of the carbene moiety.