The Contribution Made by Triphenylphosphane in the Putative Catalysis by Ruthenium Species in Conjugate Additions of β‐Dicarbonyl Compounds
Triphenylphosphane catalyzes conjugate additions of β-dicarbonyl compounds to π-acceptor olefins and dialkyl azodicarboxylates. Formation of quaternary centers at the nucleophiles has been achieved. The catalytic action of tris(triphenylphosphane)ruthenium(II) chloride and tetrakis(triphenylphosphane)ruthenium(II) hydride is at least partially due to the phosphane ligand.