Journal of the American Chemical Society published new progress about Amination catalysts. 277306-29-3 belongs to class chiral-phosphine-ligands, and the molecular formula is C32H40FeP2, Related Products of 277306-29-3.
Roy, Amy H.; Hartwig, John F. published the artcile< Oxidative Addition of Aryl Tosylates to Palladium(0) and Coupling of Unactivated Aryl Tosylates at Room Temperature>, Related Products of 277306-29-3, the main research area is palladium oxidative addition phenyl tosylate mechanism kinetics; crystal structure palladium phenyl bromo ferrocene diphosphine chelate preparation; mol structure palladium phenyl bromo ferrocene diphosphine chelate; aryl tosylate unactivated cross coupling Grignard palladium catalyst; biaryl unsym preparation.
Aryl tosylates are attractive substrates for Pd-catalyzed cross-coupling reactions, but they are much less reactive than the more commonly used aryl triflates. The authors report the oxidative addition of aryl tosylates to Pd(PPF-t-Bu)[P(o-tolyl)3] [PPF-t-Bu = 1-diphenylphosphino-2-(di-tert-butylphosphinoethyl)ferrocene] and to Pd(CyPF-t-Bu)[P(o-tolyl)3] [CyPF-t-Bu = 1-dicyclohexylphosphino-2-(di-tert-butylphosphinoethyl)ferrocene] at room temperature to produce the corresponding Pd(II) aryl tosylate complexes (shown as I; R = Ph, X = OTs 3; R = cyclohexyl, X = OTs 4). In the presence of added bromide ions, arylpalladium(II) bromide complexes I (R = Ph, X = Br 5 ; R = cyclohexyl, X = Br 6) were formed. The structures of 5 and 6 were determined by x-ray crystallog. The rate of oxidative addition was accelerated by addition of either coordinating or weakly coordinating anions, and the reactions were faster in more polar solvents. The mild conditions for oxidative addition allowed the development of Pd-catalyzed Kumada couplings and amination reactions of unactivated aryl tosylates at room temperature The catalysts for these mild couplings of aryl tosylates were generated from Pd precursors and the sterically hindered Josiphos-type ligands that induced oxidative addition of aryl tosylates to Pd(0) at room temperature Thus, coupling reaction of XC6H4OTs (X = 2- and 4-MeO, 4-CF3, 4-Me) or of mesityl tosylate or of 1-naphthyl tosylate with aryl Grignard reagents ArMgBr (Ar = 4-tolyl, 4-FC6H4, 4-MeOC6H4) in PhMe in presence of 0.1-1.0 mol % Pd(dba)2 and PPF-t-Bu at either 25° or 80° gave the corresponding biaryls in 40-86% yields.
Journal of the American Chemical Society published new progress about Amination catalysts. 277306-29-3 belongs to class chiral-phosphine-ligands, and the molecular formula is C32H40FeP2, Related Products of 277306-29-3.
Referemce:
Phosphine ligand,
Chiral phosphine ligands in asymmetric synthesis. Molecular structure and absolute configuration of (1,5-cyclooctadiene)-(2S,3S)-2,3-bis(diphenylphosphino)butanerhodium(I) perchlorate tetrahydrofuran solvate