A New Mixed P,S‐Bidentate Ligand Featuring a λ 4 ‐Phosphinine Anion and a Phosphanyl Sulfide Group − Synthesis, X‐ray Crystal Structures and Catalytic Properties of Its Chloro(cymene)ruthenium and Allylpalladium Complexes

1,3,2‐Diazaphosphinine ( 1 ) reacts successively with diphenylacetylene and diphenyl(1‐propynyl)phosphane sulfide to afford the P,S‐bidentate phosphinine 3 . Reaction of n BuLi with 3 followed by complexation with [RuCl 2 (C 10 H 14 )] 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 [PdCl 2 (η 3 ‐C 3 H 5 )] 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)