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Preparation and crystal structure of the oxalato-bridged CrIII–AgItwo-dimensional compound {Ag3(H2O)[Cr(dpa)(ox)2]3}n·2nH2O (dpa = 2,2′-dipyridylamin…
2004
The reaction of the mononuclear complex [Cr(dpa)(ox)2]− (dpa = 2,2-dipyridylamine) with Ag+ in aqueous solution affords the two-dimensional compound {Ag3(H2O)[Cr(dpa)(ox)2]3}n·2nH2O (1) whose structure has been determined by single-crystal X-ray diffraction. Six crystallographically independent metal atoms (three chromium and three silver atoms) occur in 1. The three [Cr(dpa)(ox)2]− units in 1 act as ligands towards the silver atoms through the two oxalate groups. Each oxalate group acts as bridging ligand adopting five coordination modes: bis-bidentate, bis-bidentate/monodentate (outer), bis-bidentate/monodentate (inner), bidentate/bis-monodentate (outer) and bidentate/monodentate (outer).…
Vanadium complexes with multidentate amine bisphenols
2014
The reaction of VO(acac)2 (acac(-) = acetyl acetonate) with tripodal glycine bisphenol H3L(1) under an ambient atmosphere yields a hexacoordinated vanadium(iv) complex [V(acac)(L(1))] (1). The corresponding reactions with tripodal 2-propanolamine bisphenol H3L(2) and potentially pentadentate ethoxyethanolamine bisphenol H3L(3) lead to the oxidation of the metal centre and formation of mononuclear oxovanadium(v) complexes [VO(L(2))] (2) and [VO(L(3))] (3), respectively. Alternatively, these latter two complexes can be prepared using VOSO4·5H2O or VO(OPr)3 as a precursor. The CV of 1 in an ACN solution shows a reversible one-electron process at E1/2 = +1.18 V, whereas 2 and 3 have an irrevers…
Comprehensive Uranium Thiophosphate Chemistry: Framework Compounds Based on Pseudotetrahedrally Coordinated Central Metal Atoms
2013
The new ternary compounds UP2S6, UP2S7, U(P2S6)2, and U3(PS4)4 were prepared from uranium metal, phosphorus pentasulfide, and sulfur at 700 °C. The crystal structures were determined by single-crystal X-ray diffraction methods. UP2S6 (I) crystallizes in the ZrP2S6 structure type [tetragonal, P42/m, a = 6.8058(7) A, c = 9.7597(14) A, Z = 2], which consists of central uranium(IV) atoms coordinated by P2S64– anions (staggered conformation). The anions are two-dimensional connectors for four uranium cations arranged in one plane. The structure of UP2S7 (II) [orthorhombic, Fddd, a = 8.9966(15) A, b = 15.2869(2) A, c = 30.3195(5) A, Z = 16] is closely related to the monoclinic ZrP2S7 structure ty…
Benzothiazolethione complexes of coinage metals: from mononuclear complexes to clusters and polymers
2019
Abstract The reactions of 2(3H)-benzothiazolethione (Hbtt) with [AuCl(tetrahydrothiophene)] and CuBr2 were studied, and found to yield a tetranuclear cluster compound [Au(btt)]4 [1] and a polymeric structure [CuBr(btt-btt)]n.nTHF (2). Crystallographic and spectroscopic methods were used for the characterization. In 1, the monoanionic ligand acted as a bidentate bridging N,S-donor giving a molecular cluster structure of an asymmetric coordination isomer. In the formation of 2, the ligand was dimerized by forming a S–S bond after deprotonation, and coordination via nitrogen donors to metal atoms took place leading to a polymeric structure. To clarify the diversity of reactions of Hbtt with co…
X-X through-cage bonding in Cu, Ni, and Cr complexes with M3X2 cores (X=S, As).
2008
Density functional calculations on trinuclear complexes bridged by two sulfur atoms, [(tmeda)(3)Cu(3)(mu-S)(2)](3+), [(tmeda)(3)Ni(3)(mu-S)(2)](2+), and [(tmeda)(3)Ni(3)(mu-S(2))](4+), as well as on the formation of [(tmeda)(3)Cu(3)(mu-S)(2)](3+) from a dinuclear [(tmeda)(2)Cu(2)(mu-S(2))](2+) complex and a mononuclear [(tmeda)Cu(eta(2)-S(2))](+) fragment, are reported. A qualitative orbital analysis of the M(3)X(2) framework bonding is presented for the case in which each metal atom M has a square planar coordination sphere completed by one bidentate or two monodentate ligands (that is, [(L(2)M)(3)X(2)] compounds). It is concluded that a framework electron count (FEC) of 12 corresponds to …
Synthesis, Crystal Structures and Properties of [Cu(L1)2(py)2(H2O)](H2O) [HL1 = N-(5-ethyl-[1,3,4]–thiadiazole-2-yl)-toluenesulfonamidate] and [Cu(L2…
2007
A series of new N-sulfonamidate ligands and their cooper(II) complexes, [Cu(N-(5-ethyl-[1,3,4]-thiadiazole-2-yl)-toluenesulfonamidate)2(py)2(H2O)](H2O) (1) and [Cu(N-(5-ethyl-[1,3,4]-thiadiazole-2-yl)-benzenesulfonamidate)2(py)2(H2O)] (2) have been synthesized and characterized. The X-ray crystal structures of the complexes 1 and 2 have been determined. In the both two complexes, the Cu2+ ion is five-coordinated, forming a CuN4O chromophore. The ligands act as monodentate, coordinating the metal ion through a single Nthiadiazole atom. The molecules from the reaction medium (pyridine and water) also participate to the coordination of Cu2+ ion as monodentate ligands. Both two complexes have a…
New Cu(II) and Zn(II) complexes of benzolamide with diethylenetriamine: synthesis, spectroscopy and X-ray structures
2000
Abstract New benzolamide (H2bz, 5-phenylsulfonamide-1,3,4-thiadiazole-2-sulfonamide) zinc(II) and copper(II) complexes with diethylenetriamine were synthesized and characterized. The crystal structures of the [M(Hbz)2(dien)] (M=Cu(II), Zn(II); dien=diethylenetriamine) complexes were determined. The metal centre adopts a near regular square pyramidal geometry. The benzolamidate anion acts as a monodentate ligand through the thiadiazole N atom contiguous to the deprotonated sulfonamido group. Spectroscopic properties are in good agreement with the crystal structures. The EPR and electronic spectroscopic studies showed that the copper(II) species doped into the zinc(II) complex adopts a near s…
Synthesis and characterization of a Cu(II) complex of 2-benzylmercapto-5- methyl-1,3,4-thiadiazole (C10H10N2S 2)
2008
A Cu(II) complex of 2-benzylmercapto-5-methyl-1,3,4-thiadiazole was synthesized and characterized. The crystal structure of the copper complex and the free ligand were determined by single-crystal X-ray diffraction at room temperature: {[Cu(C10H10N2S2) 2(Cl)2], P1 triclinic, a = 8.1450(2) Å, b = 8.1690(2) Å, c = 10.8180(3) Å, α = 97.4040(12)°, β = 101.6270(11)°, γ = 116.1431(14)°; C10H10N2S2 ligand, Pbca orthorhombic, a = 8.7938(7) Å, b = 9.6491(7) Å, c = 25.3552(18) Å}. The metal complex framework consists of discrete units that provide crystalline stability through a network of van der Waals contacts. The Cu(II) is coordinated by two chloride ions and two 2-benzylmercapto-5-methyl-1,3,4- …
Design of single chain magnets through cyanide-bearing six-coordinate complexes
2005
Abstract The design and preparation of stable cyanide-bearing six-coordinate complexes of formula [MIII(L)(CN)x](x + l − m)− (M = trivalent transition metal ion and L = polydentate blocking ligand) are summarized here. Their use as ligands towards either fully hydrated metal ions or coordinatively unsaturated preformed species, to afford a wide variety of low-dimensional metal assemblies whose nuclearity, dimensionality and magnetic properties can be tuned, is also reviewed. Special emphasis is put on the appropriate choice of the end-cap ligand L whose denticity determines the number of coordinated cyanide groups in the mononuclear precursors. Among the different new spin topologies obtain…
[Cr(dmbipy)(ox)2]−: a new bis-oxalato building block for metal assembling. Crystal structures and magnetic properties of XPh4[Cr(dmbipy)(ox)2]·5H2O (…
2010
The synthesis, X-ray structure and variable-temperature magnetic study of new compounds of formula PPh4[Cr(dmbipy)(ox)2]·5H2O (1), AsPh4[Cr(dmbipy)(ox)2]·5H2O (2), {Ba(H2O)2[Cr(dmbipy)(ox)2]2}n·17/2nH2O (3) and {Ag(H2O)[Cr(dmbipy)(ox)2]}n·3nH2O (4) (PPh4+ = tetraphenylphosphonium cation; AsPh4+ = tetraphenylarsonium cation; dmbipy = 4,4′-dimethyl-2,2′-bipyridine; ox2− = oxalate dianion) are reported herein. The isomorphous compounds 1 and 2 are made up of discrete [Cr(dmbipy)(ox)2]− anions, XPh4+ cations [X = P (1) and As (2)] and uncoordinated water molecules. The chromium environment in 1 and 2 is distorted octahedral with Cr–O and Cr–N bond distances varying in the ranges 1.950(2)–1.9782…