Umpolung coupling of pyridine-2-carboxaldehydes and propargylic carbonates via N-heterocyclic carbene/palladium synergetic catalysis†
Abstract
The umpolung cross-coupling reaction of pyridine-2-carboxaldehydes and propargylic carbonates has been developed for the first time through N-heterocyclic carbene/palladium cooperative catalysis with the judicious selection of the palladium catalyst, ligand and N-heterocyclic carbene, giving the propargylic ketones regioselectively.