80545-62-6Relevant articles and documents
Hydrogen activation by an aromatic triphosphabenzene
Longobardi, Lauren E.,Russell, Christopher A.,Green, Michael,Townsend, Nell S.,Wang, Kun,Holmes, Arthur J.,Duckett, Simon B.,McGrady, John E.,Stephan, Douglas W.
supporting information, p. 13453 - 13457 (2015/03/30)
Aromatic hydrogenation is a challenging transformation typically requiring alkali or transition metal reagents and/or harsh conditions to facilitate the process. In sharp contrast, the aromatic heterocycle 2,4,6-tri-tert -butyl-1,3,5-triphosphabenzene is shown to be reduced under 4 atm of H2 to give [3.1.0]bicylo reduction products, with the structure of the major isomer being confirmed by X-ray crystallography. NMR studies show this reaction proceeds via a reversible 1,4-H2 addition to generate an intermediate species, which undergoes an irreversible suprafacial hydride shift concurrent with P - P bond formation to give the isolated products. Further, para-hydrogen experiments confirmed the addition of H2 to triphosphabenzene is a bimolecular process. Density functional theory (DFT) calculations show that facile distortion of the planar triphosphabenzene toward a boat-conformation provides a suprafacial combination of vacant acceptor and donor orbitals that permits this direct and uncatalyzed reduction of the aromatic molecule.
Phosphane, phosphite, phosphido complexes of vanadium(V)
Preuss,Steidel,Vogel,Overhoff,Hornung,Towae,Frank,Reiss,Mueller-Becker
, p. 1220 - 1228 (2008/10/09)
Complex formation of tert-butylimidovanadium(V)trichloride (1) with phosphanes und phosphites has been studied. Syntheses of phosphidovanadium(V) compounds tC4H9N=VCp(NHtC4H 9)[P(SiMe3)2] and tC4H9N=VCp(NiProp 2)(PR2) (R = SiMe3, Ph) are described starting from the corresponding chlorovanadium(V) complexes. The reaction of 1 with silver hexafluorophosphate yields a bis(fluoro)phosphidovanadium(IV) complex [(μ-PF2)2V2Cl2(N tC4H9)2]; as primary intermediate product of the unknown redox reaction a cationic vanadium(V) complex [tC4H9N=VCl2 · PPh3]+PF6- has been isolated. 1 reacts with an excess of diisopropylamine forming tC4H9N=V(NiProp2)Cl 2 (16); in addition the following diisopropylamido-tert-butylimidovanadium(V) compounds tC4H9N=VCp(NiProp2)Cl (3) and tC4H9N=V(NiProp2)X 2 (X = CH2CMe3, OtC4H9, CH3COO) has been prepared. All compounds obtained are characterized by 1H, 51V, 31P NMR spectroscopy. The X-ray diffraction analysis of 16 and 3 indicate a planar coordination sphere of the amido nitrogen atom.
Compounds with Vanadium-Nitrogen and Vanadium-Oxygen Multiple Bonds
Hills, Adrian,Hughes, David L.,Leigh, G. Geffery,Prieto-Alcon, Rafael
, p. 3609 - 3618 (2007/10/02)
Vanadium nitrido complexes are generally not accessible by routes successful in rhenium and molybdenum chemistry.The vanadium-nitrogen triple bond is reactive, and easily forms phosphiniminato complexes, two of which and V(NPMe2P