80545-62-6Relevant academic research and scientific papers
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.
Sulfinylamine metathesis at oxo metal species - Convenient entry into imido metal chemistry
Rufanov, Konstantin A.,Kipke, Jennifer,Sundermeyer, Joerg
, p. 1990 - 1997 (2011/04/16)
The exchange of terminal metal oxo functionalities by N-organo and N-sulfonylimido functionalities via metathesis with bent, thus very reactive sulfinyl amines R-NSO and sulfinyl sulfonylamides R-SO2-NSO is described. It is demonstrated that in many cases sulfinyl amine metathesis offers a more convenient entry into imido complex synthesis than the much better investigated isocyanate metathesis at oxo complexes or condensation reactions with amines and silylated amines. Improved syntheses for some known key compounds and several new complexes of the type [V(NR)Cl3] and [M(NR)2Cl2] (M = Cr, Mo, W) are described. Emphasis is put on the synthesis of formerly unknown base free Lewis acids with electron-withdrawing N-substituents such as haloaryl and sulfonylaryl. Surprisingly, even [CrO2Cl2] is selectively transformed by sulfinylamines into aryl imido derivatives without any reduction by sulfur dioxide. The molecular structures of novel haloaryl imido complexes [Cr(NAr)2Cl2] Ar = C6F5 and 2,4,6-Cl3C6H2 as determined by X-ray crystallography are reported. The Royal Society of Chemistry 2011.
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.
Coordination Compounds of tert-Butyliminovanadium(V) Trichloride with O-Donor-Ligands
Preuss, F.,Hornung, G.,Frank, W.,Reiss, G.,Mueller-Becker, S.
, (2008/10/08)
The reaction of tert-butyliminovanadium(V) trichloride (1) with cyclic and acyclic ethers, ethylene carbonate and thietane has been studied. The1:1-complexes have a different stability; reversible and irreversible cleavage of ether in the coordination sphere of the vanadium atom rearranging in ω-chloroalkanolato lignads are observed. The reaction of 1 with 2-chloroethanol, 3-chloropropanol and 5-chloropentanol yields the complexes tC4H9N=V(OR)Cl2 (R=CH2CH2CH2CH2CH2Cl) and [tC4H9NV(OR)Cl2]*ROH;in the presence of triethylamine the disubstituted compounds tC4H9N=V(O R)2Cl are formed. The (51)V NMR spectra are discussed. The crystal structure of [tC4H9N=VCl3*DME] (12) and [tC4H9N=V(OCH2CH2Cl)Cl2*HOCH2CH2Cl] (13) has been determined. The vanadium atoms in 13 have a distorted octahedral coordination and are linked by the oxygen atoms of the 2-chloroethanolato lignads forming a binuclear complex. In solution molecular weight measurement and (51)V NMR data indicate the equilibrium between a mononuclear complex (13) and its isomer [tC4H9N=V(OCH2CH2Cl)2Cl*HCl].
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
Reaction of Oxovanadium(V) Trichloride with tert-Butylamine and Silylated Derivatives
Preuss, Fritz,Fuchslocher, Edith,Leber, Edith,Towae, Willi
, p. 271 - 277 (2007/10/02)
The reaction of VOCl3 with tert-butylamine and silylated derivatives has been studied.O=VCl2tC4H9(R)> (R = SiMe3, SiMe2NHtC4H9), O=V(OSiMe3)2Cl and binuclear vanadium(V) complexes with bridging oxo and nitrogen ligands have been prepared; their spectroscopic data (1H NMR, 51V NMR, IR) are reported.A simple route for preparing tC4H9N=VCl3 and tC4H9N=V(O)Cl>n is described including complex formation with pyridine and chloride ions. - Keywords: Amino and Iminovanadium(V) Compounds, Preparation, 51V NMR Spectra
Synthesis and Properties of tert-Butyliminovanadium(V) Compounds tC4H9N=VX3 (X = Cl, RCOO)
Preuss, Fritz,Towae, Willi
, p. 1130 - 1135 (2007/10/02)
tC4H9N=V(OSiMe3)3 has been prepared by reaction of NH4VO3 with HNSiMe3(tC4H9).This compound is the starting material for the synthesis of C6H5N=V(OSiMe3)3 and tC4H9N=VCl3 by transamination with aniline or redistribution with VOCl3, respectively.The properties of the trichloride are studied by chemical reactions such as redistribution, complex formation and substitution with silver carboxylates.All compounds are monomeric in solution, probably containing a nitrogen vanadium triple bond.The structure of 2,2'-dipyridyl complexes tC4H9N=VX3*C10H8N2> (X = Cl, CH3COO) has been found to be octahedral with meridional arrangement of chloride or acetate ligands. - Key words: tert-Butyliminovanadium(V) Trichloride and Tricarboxylates, 1H NMR Spectra, IR Spectra
