13470-26-3Relevant articles and documents
Low-temperature Syntheses of Vanadium(III) and Molybdenum(IV) Bromides by Halide Exchange
Calderazzo, Fausto,Maichle-Moessmer, Caecilie,Pampaloni, Guido,Straehle, Joachim
, p. 655 - 658 (1993)
Halide-exchange reactions of VCl4 or MoCl5 with dry HBr at temperatures between ca. -50 and +20 deg C afforded the corresponding bromides, VBr3 or MoBr4, in good yields, presumably via the formation of unstable higher-valent bromide intermediates which undergo spontaneous loss of bromine.In corresponding reactions with HI the exchange was incomplete and mixed halides were obtained.At room temperature the VCl4-HI system gave VCl3 in an almost quantitative yield.By reaction of MoBr4 with tetrahydrofuran (thf) was isolated and its crystal structure determined: orthorhombic, space group Pbcn (no. 60), a = 8.812(2), b = 13.882(5), c = 14.279(3) Angstroem, Z = 4, R = 0.063.The molecule has the usual meridional geometry, typical of other derivatives (X = Cl or I).
Preparations, structures, and properties of sulfato-bridged dinuclear and tetranuclear vanadium(III) complexes with a dinucleating ligand, 2-oxo-N,N′-bis(2-pyridylmethyl)-1,3-propanediamine-N,N′-diacetate
Kanamori, Kan,Matsui, Naoto,Takagi, Kentaro,Miyashita, Yoshitaro,Okamoto, Ken-Ichi
, p. 1881 - 1888 (2006)
New dinuclear and tetranuclear vanadium(III) complexes with sulfato bridge(s), [{VIII(H2O)}2(μ-hpnbpda)-(μ- OH)(μ-SO4)]·5.25H2O (1) and [V III4(μ-hpnbpda)2(μ-OH) 2(μ-SO4)2]·12H2O (2), where hpnbpda is an alkoxobridging dinucleating ligand, 2-oxo-N,N′-bis(2- pyridylmethyl)-1,3-propanediamine-N,N′-diacetate, were prepared, and their structures were determined by X-ray crystallography. The vanadium(III) center in 1 adopts heptacoordinate structure while that in 2 has a hexacoordinate structure. In 2, the two dinuclear vanadium(III) units bridged by the alkoxo group of hpnbpda are further linked by two hydroxo and two sulfato bridging groups, resulting in a dimer-of-dimers structure. Measurement of the temperature dependence of the magnetic susceptibility of 1 revealed that the two vanadium(III) ions are antiferromagnetically coupled with J = -5.9 cm -1 and g = 1.90.
Heptacoordinate vanadium(III) complexes containing a didentate sulfate ligand. X-ray structures of [V2(SO4)3{N, N′-bis(2-pyridylmethyl)-1,2-ethanediamine}2] and [V(SO4){N,N,N′, N′-tetrakis(2-pyridylmethyl)-1,2-ethanediamine}]+ and their solution properties
Kanamori, Kan,Kameda, Eiji,Okamoto, Ken-Ichi
, p. 2901 - 2909 (1996)
Several vanadium(III) complexes with a tetradentate N,N′-bis(2-pyridylmethyl)-1,2-ethanediamine (bispicen) or a hexadentate N,N,N′,N′-tetrakis(2-pyridylmethyl)-1,2-ethanediamine (tpen) ligand were prepared and characterized by UV-vis and Raman spectroscopy. Of these complexes, the structures of two vanadium(III) complexes with a didentate sulfate were determined by X-ray crystallography. [V2(SO4)3(bispicen)2] crystallizes in the monoclinic space group ClIc with a=25.083(7), b=24.236(5), c=15.708(5) A, β=114.96(2)°, Z=8, and R=0.087. The complex containing the [V(SO4)-(tpen)+ cation crystallizes in the orthorhombic space group Aba2 with a=20.1836(8), b=19.793(1), c=15.6107(7) A, Z=8, and R=0.069. Both complexes adopt a heptacoordinate pentagonal bipyramidal structure in which the didentate sulfate is situated in the pentagonal plane. The heptacoordinate structure of the tpen-SO42- complex is stable in an aqueous solution, whereas the bispicen-SO42- complex is easily aquated to yield a hexacoordinate oxo-bridged dinuclear species.
Syntheses, Characterization, and Properties of Vanadium(III) Complexes Containing Tripodal Tetradentate Ligands with Single Pyridyl Groups
Kanamori, Kan,Kameda, Eiji,Kabetani, Takatsugu,Suemoto, Taiko,Okamoto, Ken-ichi,Kaizaki, Sumio
, p. 2581 - 2590 (2007/10/03)
The syntheses, characterization, and properties of (1a), (1b), (2), and Br2 (3) are described, where pda (N-(2-pyridylmethyl)iminodiacetate), bpg (N,N-bis(2-pyridylmethyl)glycinate), and tpa (tris(2-pyridylmethyl)amine) are tripodal tetradentate ligands with single pyridyl groups.Complexes 1a, 1b, and 2 were characterized on the basis of their electronic and Raman spectra.The structure of 3 was determined by X-ray crystallography.Complex 3 crystallizes in the P space group with the following unit cell dimensions: a=11.505(5), b=11.509(5), c=16.348(7) Angstroem, α=103.73(2) deg, β=103.71(2) deg, γ=93.26(3) deg, and Z=2.The V-O-V angle is 175.3(2) deg and the V-μ-O distances are 1.783(2) and 1.784(2) Angstroem.In complex 3, the four unpaired electrons are ferromagnetically coupled.It was found that there is a positive correlation between 2 * νas(V-O-V) and the energy of the oxo-to- V(III) charge-transfer transition for single oxo-bridged dinuclear vanadium(III) complexes including the present complexes.This correlation is discussed in terms of the ? character of the V(III)-μ-O bond that is affected by the remaining donor groups.
