Mechanism of Ligand‐Controlled Chemoselectivity‐Switchable Ni‐Catalyzed C−N Cross‐Coupling of Amine

Abstract

Ni‐catalyzed C−N cross‐coupling of 5‐aminoindole and 2‐chloroquinoline provides a ligand‐controlled chemoselectivity‐switchable method for construction of arylamines. In this study, we employed density functional theory methods to elucidate the mechanistic details of this reaction and the origin of different chemoselectivity induced by Phen‐DalPhos and PAd2‐DalPhos. The calculation indicating that the catalytic cycle mainly proceeds through the oxidative addition of 2‐chloroquinoline, anion exchange with 5‐aminoindole and C−N reductive elimination. Meanwhile, the turnover‐limiting step is the reductive elimination of C−N bond. The intrinsic electric property of 5‐aminoindole (Phen‐DalPhos) control the chemoselectivity, leading to the preference of (hetero)aniline cross‐coupling. In addition, the stronger electron‐withdrawing ligand PAd2‐DalPhos, leading to the preference of indole N‐arylation