Asymmetric 1,4-addition of arylboronic acids to 2,3-dihydro-4-pyridones catalyzed by axially chiral NHC-Pd(II) complexes

Abstract

Axially chiral cis-chelated bidentate bis(N-heterocyclic carbene)-palladium(II) complexes are effective catalysts for the asymmetric conjugate addition of arylboronic acids to 2,3-dihydro-4-pyridones, producing the synthetically and biologically important 2-aryl-4-piperidones in moderate-to-high yields (up to 96%) along with excellent enantioselectivities (up to >99.5% ee) in most cases under mild conditions.