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

Keywords: Density functional calculations / Homogeneous catalysis / P ligands / Ruthenium / Palladium / S ligands 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 nBuLi 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

Dinuclear Tetrapyrazolyl Palladium Complexes Exhibiting Facile Tandem Transfer Hydrogenation/Suzuki Coupling Reaction of Fluoroarylketone

“…Indeed, a similar order of reactivity was reported with higher transfer hydrogenation activity for 4-fluoroacetophenone compared to its bromo-analogues. 24 These results suggest that fluoro substituent in 4-haloacetophenone induces highest activity in reductive hydrogenation of its carbonyl group into alcohol. We, therefore, suggest that the productive tandem reaction for 4-fluoroacetophenone, unlike its chloro-and bromo-analogues, is due to the result of a facile reductive transformation of keto group into alcohol, which undergo a subsequent C-C coupling reaction with phenylboronic acid (see the reaction sequence under caption of Table 2).…”

A ruthenium(ii) bis(phosphinophosphinine) complex as a precatalyst for transfer-hydrogenation and hydrogen-borrowing reactions

“…§ [Ru(η 6 -p-cymene){1-Bu-2-P(S)Ph 2 -3-Me-5,6-Ph 2 -PC 5 H}Cl], a Ru complex of a phosphacyclohexadienyl anion bearing a sulfur donor, was also shown to perform poorly as a catalyst requiring 2.5 days at 80°C to go to completion. 6 A catalyst with a higher activity (full conversion after 1 minute at room temperature) has been demonstrated with a Ru complex bearing NH functionality that undergoes ligandactivation with base, 37 and a Ru pyridyl-phosphole complex has shown full conversion at extremely low loadings (5 × 10 −6 mol%) at 90°C. 38 § Activation of the precatalyst with KO t Bu could affect the phosphinine moieties (leading to B and C) as well as substituting the Cl ligands.…”

“…Thermal ellipsoid plots (50%) of the molecular structures of 2 (A) and 4 (B, Ph rings in 4 are displayed without thermal ellipsoids for clarity). Selected bond distances (Å) and angles (°) for 2: P(1)-C(1) 1.754 (3), C(1)-C(2) 1.423(4), C(2)-C(3) 1.404(4), C(3)-C(4) 1.393(4), C(4)-C(5) 1.396(4), C(5)-P(1) 1.749(3), C(1)-P(2) 1.847(3), C(1)-P(1)-C(5) 103.6(1), P(1)-C(1)-P(2) 119.9(1); for 4: P(1)-Ru(1) 2.310(2), P(2)-Ru(1) 2.342(2), P(3)-Ru(1) 2.241(2), P(4)-Ru(1) 2.369(2), Ru(1)-Cl(1) 2.430(2), Ru(1)-Cl(2) 2.477(2), P(1)-Ru(1)-P(2) 69.89(6), P(3)-Ru(1)-P(4) 70.32(5).…”

New anionic and dianionic polydentate systems featuring ancillary phosphinosulfides as ligands in coordination chemistry and catalysis

“…Palladium chloride complexes such as 3 proved to be particularly robust and could be employed as very efficient catalysts in CeC (Suzuki) and CeB (SuzukieMiyaura) coupling reactions. Coupling reactions of pinacolborane with iodoarenes yielded the corresponding boronic esters with excellent yields with low catalyst loading (TON between 5 Â 10 3 and 10 Â 10 3 ) [17].…”