Molecular Structure of Bis[salicylaldehyde-2-hydroxyanilato(2—)]vanadium(IV) By the reaction of tris(acetylacetonato)vanadium(III) with salicylaldehyde-2-hydroxyanil the non-oxo vanadium(IV) complex of this ligand was prepared. Bis[salicylaldehyde-2-hydroxyanilato(2—)]vanadium(IV) has a distorted octahedral structure. Crystallographic data see “Inhaltsübersicht”. 相似文献
Reactions and Thermal Behaviour of Nonoxo Vanadium(IV) Complexes. Crystal Structures of Methoxo-oxo[thenoyltrifluoroacetone-salicylhydrazonato(2–)]vanadium(V) and Methoxo-oxo[benzoylacetone-salicylhydrazonato(2–)]vanadium(V) The persistence of non-oxo vanadium(IV) complexes in dichlormethane/methanol/water solutions was studied by UV/VIS spectroscopy. The reaction products methoxo-oxo-[thenoyltrifluoroacetone-salicylhydrazonato(2–)]vanadium(V) and methoxo-oxo[benzoylacetone-salicylhydrazonato(2–)]vanadium(V) were isolated and characterized by X-ray analysis. The thermal behaviour of non-oxo vanadium(IV) complexes was checked. 相似文献
Titanium(IV) Complexes with Tridentate Diacidic Ligands. Crystal Structure of Bis[2,6-diphenacylpyridinato(2–)]titanium(IV) The titanium(IV) chelates with 2,2′-dihydroxy-azobenzene, salicylaldehyde-2-hydroxyanil, 2-(2′-hydroxyphenyl)-8-quinolinol, 2,6-diphenacylpyridine as well as with aroylhydrazones of salicylaldehyde, benzoylacetone and thenoyltrifluoroacetone were synthesized by ligand exchange reactions of titanium(IV)-isopropoxide. The compounds are red or black in colour and were identified by distinct molecular peaks in the mass spectra. The crystal and molecular structure was determined for bis[2,6-diphenacylpyridinato(2–)] titanium(IV). Crystallographic data see “Inhaltsübersicht”. 相似文献
Force field calculations were performed on a series of 27 transition metal complexes of titanium(IV), vanadium(IV/V), copper(II), nickel(II), molybdenum(IV/V), rhenium(IV/V), and tin(IV) with a broad variety of di- or tridentate ligands in order to find a reliable scheme for determining the molecular structure of such chelates with the new Extensible Systematic Force Field (ESFF). A good agreement between theoretical results and experimental data was achieved. In some cases an unspecific fitting of the force field was necessary. 相似文献
Vanadium Complexes with Tridentate Diacidic Ligands. The Crystal Structures of Bis[acetylacetonato-thiobenzoylhydrazonato(2-)]vanadium(IV), Methoxo-oxo-[salicylaldehyd-thiobenzoylhydrazonato(2-)]vanadium(V), and Methoxo-oxo-[salicylaldehydbenzoylhydrazonato(2-)]methanol Vanadium(V) By template reactions of bis(acetylacetonato)oxovanadium(IV) and bis(salicylaldehydato)oxo-vanadium(IV), respectively, with benzoylhydrazine, thiobenzoylhydrazine, and 2-aminophenol the vanadium(IV) complexes V(LLL)2 of tridentate azomethine ligands LLL were synthesized. The complexes were characterized by EPR spectroscopy and by absorption spectroscopy. From the complex V(LLL)2 ( 1 ), in which LLL is acetyl-aceton-thiobenzoydrazonate(2-), the crystal structure analysis was solved. The vanadium atom in 1 is coordinated trigonal-prismatically by two N, 0 and S atoms. Furthermore, the 0x0 vanadium(V) complexes[VO(LLL)(OCH,)] (6) with LLL = salicylaldehyd-thio-benzoylhydrazonato(2-) and [VO(LLL)(OCH3)· -CH3OH] (7) with LLL = salicylaldehydbenzoylhydrazonato(2-) were identified by X-ray diffraction and by IR spectroscopy in the reaction products. Crystallographic data for 1, 6 , and 7 see ?Inhaltsübersicht”?. 相似文献
The synthesis and structural characterization of four new trimethylplatinum(IV) iodide complexes of 2,2′‐bipyridine ligands {[PtMe3(4,4′‐Clbipy)I] ( 1 ), [PtMe3(4,4′‐Brbipy)I] ( 2 ), [PtMe3(4,4′‐CNbipy)I] ( 3 ) and [PtMe3(4,4′‐NO2bipy)I] ( 4 )} are reported. The 1H NMR spectra of the complexes reveal the presence of two chemically distinct methyl groups in the complexes. X‐ray crystal structures of complexes 1 – 4 show that the platinum metal center in each of the complexes form distorted octahedral structure being surrounded by methyl groups, bipyridine ligand, and iodine atom. Furthermore, the crystal packing study shows that self‐assembly of the complexes are governed by weak hydrogen bonding and other non‐covalent interactions such as π ··· π, halogen ··· π and C–H ··· π interactions. Complex 1 exhibits infinite one‐dimensional zigzag chain structure and other three complexes form infinite ladder type structures. 相似文献
The preparation of oxovanadium(IV, V) coordination compounds with 2‐acetylpyridine‐2‐furanoylhydrazone (Hapf) is described. [VO(apf)(acac)] was prepared from oxovanadium(IV) diacetylacetonate [VO(acac)2] by reaction with Hapf in methanol or dichloromethane. The complex is paramagnetic and its EPR spectrum is consistent with an octahedral coordination for the vanadium(IV) atom. Voltammetry studies of [VO(apf)(acac)] indicate an irreversible oxidation, in agreement with the chemical behavior of the compound in solution. The vanadium(IV) complex undergoes slow oxidation in alcoholic solution, losing the acetylacetonate ligand to form [VO2(apf)] and [V2O2(μ‐O)2(apf)2]. The crystal structures of these last compounds were determined by X‐ray diffraction methods. [V2O2(μ‐O)2(apf)2] crystallizes monoclinic [P21/c, Z = 2, a = 817.400(10), b = 1650.90(3), c = 984.70(2) pm, β = 112.7190(10)°]. The crystal structure consists of dimeric units, in which two μ‐oxo ligands subtend asymmetric bridges between the vanadium atoms in a very distorted octahedral coordination. In the crystal of [VO2(apf)], orthorhombic [Pnma, Z = 4, a = 1630.000(10), b = 675.10(4), c = 1136.40(2) pm], the vanadium(V) atom is pentacoordinated. 相似文献
Unsymmetrical and symmetrical mononuclear and insoluble polynuclear oxo-vanadium(IV) Schiff-base complexes were prepared and characterized. The complexes [VO(5-x-6-y-Sal)(5-x′-6-y′-Sal)en)] (where x, x′ = H, Br and y, y′ = H, OMe) were obtained in monomeric form while for x or x′ = NO2 polymers were produced. In the case of [VO(5-x-6-y-Sal)(5-x′-6-y′-Sal)pn)] with a six-member N–N chelating ring, oxo-vanadium(IV) complexes were polynuclear. The tetradentate N2O2-Schiff-base ligands are coordinated in the equatorial plane of oxo-vanadium(IV). Electrochemical and spectroscopic data (UV–Vis and IR) suggest importance of coordination geometry and the substiuents on phenyl rings and the bridge group. Electron density of the vanadium center decreases by the electron-withdrawing groups on the ligand while electron density on vanadium increases via σ-donation of phenolic oxygen. 相似文献
Complexes with N,N,N′,N′-Tetrakis(2-hydroxybenzyl)ethylenediamine (H4tben). Crystal Structure of Ti(tben) The complexes of N,N,N′,N′-tetrakis(2-hydroxybenzyl)-ethylenediamine with titanium(IV), vanadium(IV), manganese(IV), and tin(IV) were synthesized and characterized by mass spectrometry. The Mössbauer date were evaluated for the tin compound. The molecular structure of the titanium(IV) complex was determined by X-ray structural analysis, crystallographic data see “Inhaltsübersicht”. 相似文献
Complexes of Vanadium and Titanium with Salicylaldehyde benzoylhydrazone and 2-(2′-Hydroxyphenyl)-8-quinolinol. Crystal Structure of μ-Oxo-bis[oxo{2-(2′-hydroxyphenyl)-8-quinolinato(2-)}-vanadium(V)] . By reaction of titanium(IV)-isopropoxide and bis(acetylacetonato)-oxovanadium(IV) with salicylaldehyde benzoylhydrazone and 2-(2′hydroxyphenyl)-8-quinolinol, respectively, the metal complexes of the tridentate diacidic ligands were synthesized and characterized mass spectrometrically. The mass spectra of the titanium compounds correspond to the expected bisligand complexes whereas several species are demonstrable in the case of vanadium. Crystals of μ-oxo-bis[oxo{2-(2′-hydroxyphenyl)-8-quinolinolato(2-)}-vanadium(V)] were isolated and characterized by X-ray structural analysis. The complex exhibits C2 symmetry, accordingly the μ2-oxygen atom is situated on the 4 axis. The VOV bridge is angular with the unusually small bond angle of 107.3°. The coordination polyhedron is distorted octahedral. The compound additionally contains one molecule of chloroform per formula unit which is disordered in two positions. Crystallographic data see “Inhaltsübersicht”. 相似文献
Four novel oxovanadium(IV) binuclear complexes have been synthesized, namely [(VO)2(IPHTA) (L)2SO4 (L denotes 2,2′-bipyridine (bpy); 1,10-phenanthroline (phen); 4,4′-dimethyl-2,2′-bipyridine (Me2bpy) and 5-nitro-1,10-phenanthroline (NO2-phen)), where IPHTA is the isophthalate dianon. Based on elemental analyses, molar conductivity measurements, IR and electronic spectra studies, it is proposed that these complexes have IPHTA-bridged structures and consist of two vanadium(IV) atoms in a square-pyramidal environment. The complexes [(VO)2(IPHTA)(Me2bpy)2]SO4 (1) and [(VO)2(IPHTA)(bpy)2]SO4 (2) were characterized by variable temperature magnetic susceptibility (4–300 K) and the data could be well fitted by the least-squares method to a susceptibility equation derived from the spin Hamiltonian operator,
. The exchange integral, J, was found to be −26.8 cm−1 for (1) and −31.0 cm−1 for (2). These results are commensurate with antifferomagnetic interactions between two oxovanadium(IV) ions within each molecule. The influence of different terminal ligands on magnetic interactions between the metals of this kind of complexes is also discussed. 相似文献
A series of new complexes of oxovanadium(IV) [VO(L)(B)] and ruthenium(II) [Ru(CO)(PPh3)2(L)] ( 1.1- 1.3, 2.1–2.3 ) (H2L = dehydroacetic acid Schiff base of S‐methyldithiocarbazate, H2smdha ( 1 ) or S‐benzyldithiocarbazate, H2sbdha ( 2 ); B = 2,2′‐bipyridine (bpy) or 1,10‐phenanthroline (phen)) have been synthesized. The structure of these complexes was authenticated using elemental analyses and spectroscopic techniques, and their magnetic properties and electrochemical behaviour were studied. The molecular structures of oxovanadium(IV) complexes [VO(smdha)(bpy)]?CH2Cl2 ( 1.1 ) and [VO(sbdha)(phen)]?2H2O ( 2.2 ) were confirmed using single‐crystal X‐ray crystallography. Analytical data showed that the ligands 1 and 2 are chelated to the metal centres in a bi‐negative tridentate fashion through azomethine N, thiol S and deprotonated hydroxyl group. The antioxidant activity of the synthesized compounds was tested against 2,2‐diphenyl‐1‐picrylhydrazyl) radical, which showed that the complexes demonstrate a better scavenging activity than their corresponding ligands. The cupric ion reducing antioxidant capacity method was also employed and the total equivalent antioxidant capacity values were found to be higher for the oxovandium(IV) complexes. DNA binding affinity of the compounds was determined using UV–visible and fluorescence spectra, revealing an intercalation binding mode. Higher cytotoxicity for the complexes compared to their ligands was found against human liver hepatocellular carcinoma (HepG2) and breast adenocarcinoma (MCF7) cell lines using MTT assay. 相似文献
Tin(IV) Complexes with Tridentate Diacidic Ligands By template reactions including bis(acetylacetonato)-dichloro-tin(IV) and O-aminophenol as well as o-aminothiophenol, benzoylhydrazine, and thiobenzoylhydrazine the tin chelates of tridentate diacidic ligands containing ligator atoms were prepared. To characterize the compound, IR, UV-VIS and Mössbauer spectroscopy were used. Crystal structure analyses demonstrate the existence of disturbed octahedral structures. Bis[acetylacetonbenzoylhydrazonato(2-)]tin(IV): space group P21/c, Z = 4, 2501 observed unique reflections, R = 0.045. Lattice dimensions at 20°C: a = 992.3, b = 2405.5, c = 1071.8pm, β = 116.94°. Bis[acetylacetonthiobenzoylhydrazonato(2-)] tin(IV): space group P21/c, Z = 4, 3603 observed unique reflections, R= 0.029. Lattice dimensions at 20°C: a = 1581.5, b = 947.8, c = 1644.9pm, β = 90.32°. 相似文献
Tin(IV) Complexes with Tridentate Diacidic Ligands — 119Sn NMR and 119mSn Mössbauer Studies The tin(IV) chelates of tridentate diacidic azomethines of acetylacetone resp. salicylaldehyde with benzoylhydrazine, thiobenzoylhydrazine, 2-hydroxyaniline and 2-mercaptoaniline as well as with the ligands 2-(2′-hydroxy-4-methylphenyl)-6-(2″-hydroxyphenyl)pyridine, 2-(2′-hydroxyphenyl)-8-quinolinol and 2.6-diphenacylpyridine were synthesized. The compounds were characterized by IR-, UV/VIS-, MS-, 119Sn NMR and 119mSn Mössbauer spectroscopy. They exist as a mixture of geometrical isomers. 相似文献