A New Mixed P,S‐Bidentate Ligand Featuring a λ4‐Phosphinine Anion and a Phosphanyl Sulfide Group − Synthesis, X‐ray Crystal Structures and Catalytic Properties of Its Chloro(cymene)ruthenium and Allylpalladium Complexes

Abstract

Abstract1,3,2‐Diazaphosphinine (1) reacts successively with diphenylacetylene and diphenyl(1‐propynyl)phosphane sulfide to afford the P,S‐bidentate phosphinine 3. Reaction of nBuLi with 3 followed by complexation with [RuCl2(C10H14)]2 gave two diastereoisomers 5a,b. Variable‐temperature NMR spectroscopy and ONIOM DFT calculations were carried out to rationalize their formation. Complexes 5a,b were used as catalysts in hydrogen‐transfer hydrogenation (TON up to 200). Reaction of MeLi with 3 followed by complexation with [PdCl2(η3‐C3H5)]2 yielded two diastereomers 7a,b, which were used as catalysts in the Suzuki−Miyaura cross‐coupling reaction of aryl bromides with pinacolborane to yield the corresponding arylboronic esters (TON up to 799000). (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)