Organonickel phosphine complexes as catalysts in crosscoupling of 2-chloro-5-(trifluoromethyl)pyridine with (2,4-difluorophenyl)boronic acid

Abstract

Arylnickel phosphine complexes have been studied for more than a decade as a substitute for palladium catalysts for cross-coupling reactions because of the considerable cost of platinum-group metals. Simple replacement of palladium by nickel in catalytic systems often leads to a decrease in catalytic activity, therefore optimization of the reaction conditions and selection of appropriate ligands is required. The decrease of activity in the dppf-containing precatalyst when replacing Pd on Ni in the cross-coupling reaction of alpha-pyridyl halides with boronic acids is especially noticeable due to deactivation of the nickel catalyst 1 during the reaction [1,2].