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71.
72.
Francisco Hueso-Urea Miguel N. Moreno-Carretero Antonio L. Peas-Chamorro Jos M. Amig Vicente Esteve Tony Debaerdemaeker 《Polyhedron》1999,18(27):1666-3636
From reactions between different Cu(II) salts and the Schiff base 6-amino-5-formyl-1,3-dimethyluracil-benzoylhydrazone (H2BEZDO) in alcohol, six new copper complexes with simplified formulas [Cu(HBEZDO)(H2O)(MeOH)]NO3 (1), [CuCl(HBEZDO)(DMF)] (2), [CuBr(HBEZDO)]·2H2O (3), CuBr(HBEZDO) (4), Cu(ClO4)(HBEZDO)·H2O (5), and Cu(SO4)1/2(HBEZDO)·1H2O (6) were isolated. The structures of compounds 1, 2 and 3 have been established by means of XRD diffraction methods. In the three compounds, the Schiff base acts as a tridentate monodeprotonated ligand through the N(6), N(51) and O(52) atoms, making two five- and six-membered chelate rings. In the structure of 1 and 2, the solvent molecules are coordinated giving square-based pyramidal environments, with the basal plane completed by a MeOH (1) or Cl (2) and the apical positions occupied by the oxygen atom of a water (1) or a DMF molecule (2). The molecular unit of the complex [CuBr(HBEZDO)]·2H2O (3) is defined by a square-plane containing the three donor atoms of the organic ligand and a bromide ligand (Cu–Br 2.384 Å), but there is a stronger tetragonally elongated pyramidal geometry around the metal, the apical position of the polyhedron being occupied by a weakly bound-to-copper bromine atom (3.086 Å) of a neighbouring molecule. This fact gives the appearance of an apparent dimer with very asymmetric bromine bridges, in which there are no exchange interactions between metal centres. Also, infrared, magnetic and EPR data of the isolated complexes are reported. 相似文献
73.
Crystal Structures of the Terpyridine Complexes [Cd(terpy)Cl2], [Cu(terpy)(CN)Cl], and [Cu(terpy)][Cu(CN)3] · H2O By reaction of cadmium chloride with 2,2′ : 6′,2″-terpyridine (“terpy”) in water/acetone crystals of [Cd(terpy)Cl2] ( 1) were formed. The compound crystallizes monoclinic, space group P21/c, a = 1111.70(10), b = 823.10(7), c = 1643.00(14) pm, β = 93.913(1)°, Z = 4. Starting from mixtures of different molar ratios of copper(II) chloride, terpyridine, and KCN in water/methanole, two complexes of different composition were obtained. At the molar ratio of 1 : 1 : 2 a copper(II) coordination compound with both halide and pseudohalide ligands, [Cu(terpy)(CN)Cl] ( 2 ), was formed which also crystallizes monoclinic, P21/c, a = 1065.6(3), b = 824.6(2), c = 1644.5(7) pm, β = 98.214(3)°, Z = 4. At a molar ratio of 1 : 1 : 10 a partial reduction of copper(II) occured with formation of a mixed valency compound [Cu(terpy)][Cu(CN)3] · H2O ( 3 ) which crystallizes in the hexagonal space group P6522, with a = b = 800.29(1), c = 4771.05(7) pm, Z = 6. Compounds 1 and 2 are structurally similar, the coordination of the metal atoms is square pyramidal. Networks are formed by hydrogen bridges. In 3 the copper(II) ions show a distorted square planar coordination by the three N atoms of the terpy ligand and one N atom of a bridging CN– group, the copper(I) atoms, however, show trigonal planar coordination by three CN– ligands to which the water molecules are bonded by hydrogen bridges. Thus helical chains are formed which stretch in the direction of the screw axes. The EPR spectrum of 3 was measured. 相似文献
74.
S. Anfang J. Grebe M. Mhlen B. Neumüller N. Faza W. Massa J. Magull K. Dehnicke 《无机化学与普通化学杂志》1999,625(8):1395-1400
Synthesis and Crystal Structures of the Phosphoraneiminato Complexes [AlCl2(NPEt3)]2, [GaI2(NPEt3)]2, and [GaI2(NPPh3)]2 [AlCl2(NPEt3)]2 ( 1 ) is made according to the known method by reaction of aluminium trichloride with the silylated phosphaneimine Me3SiNPEt3 in acetonitrile; it is isolated as colourless, moisture sensitive crystals. The phosphoraneiminato complexes [GaI2(NPEt3)]2 ( 2 ) and [GaI2(NPPh3)]2 ( 3 ), on the other hand, are obtained by redox reactions as pale yellow crystals; ( 2 ) of “gallium(I) iodide” with Me3SiNPEt3 in toluene and ( 3 ) of gallium with N-iodine triphenylphosphaneimine, INPPh3, in tetrahydrofuran. 1 and 3 are characterized spectroscopically and by crystal structure determinations; 2 is characterized only crystallographically. 1 : Space group Pbca, Z = 4; lattice dimensions at –70 °C: a = 1232.6(2), b = 1341.1(2), c = 1393.4(3) pm, R1 = 0.0315. 1 forms centrosymmetric molecules in which the Al atoms are linked via Al–N bonds of the two (NPEt3–) groups; with 185.0 and 184.4 pm these bonds are of almost the same lengths. 2 : Space group Pbca, Z = 4; lattice dimensions at –80 °C: a = 1380.0(1), b = 1311.0(1), c = 1429.1(1) pm, R1 = 0.0273. 2 crystallizes isotypically with 1 . The gallium atoms of the centrosymmetric Ga2N2 four-membered ring are connected with Ga–N distances of equal length (190.9 pm). 3 · THF: Space group P212121, Z = 2; lattice dimensions at –140 °C: a = 1494.6(1), b = 1536.3(1), c = 974.6(1) pm, R1 = 0.0382. 3 forms dimeric molecules in which the gallium atoms are linked via the N atoms of the (NPPh3–) groups to form a non-planar Ga2N2 four-membered ring of C2 symmetry with Ga–N bonds of equal lengths – within standard deviations – of 194.7 pm. The phosphoraneiminato groups are arranged in a synperiplanar way. 相似文献
75.
Crystal Structure of the “Supramolecular” Complex [Cs2(18-crown-6)][HgI4] with Unusually Coordinated Cs Ions The reaction of 18-crown-6, 1,4,7,10,13,16-hexaoxacyclooctadecane, with HgI2/CsI in methanol yields crystals of [Cs2(C12H24O6)][HgI4]. The compound crystallizes monoclinically, space group P21/c, Z = 4, a = 1574.8(3), b = 1067.0(3), c = 1693.2(6) pm, and β = 98.29(3)º. The structure consists of a network made up of two different types of [Cs-(18-crown-6)-Cs]2+ cations, interconnected by [HgI4]2? anions. The cations form an “anti-sandwich” structure with relatively short Cs ? Cs distances of 382 pm in the first type of cations and a longer distance of 480 pm in the second type of cations. 相似文献
76.
Reactions of MoNCl3 and WNCl3 with Elemental Fluorine. Crystal Structures of [MoO2F2(THF)2] and [WF4(NCl)(CH3CN)] The nitrido chlorides MoNCl3 and WNCl3 as well as WCl4(NCl) react with elemental fluorine forming the N-chloro imido complexes MoF4(NCl) and WF4(NCl), which were characterized by IR spectroscopy. With tetrahydrofurane MoF4(NCl) reacts to give [MoF4(NCl)(THF)], which in THF solution slowly converts into [MoO2F2(THF)2]. From WF4(NCl) with acetonitrile the complex [WF4(NCl)(CH3CN)] is obtained. Both donor acceptor complexes were characterized by crystal structure determinations. [MoO2F2(THF)2] : Space group P21/n, Z = 4, structure solution with 1823 unique reflections, R = 0.033 for reflections with I > 2σ(I). Lattice dimensions at ?40°C: a = 636.2, b = 1119.5, c = 1625.2 pm; β = 93.92(1)º. The compound has a monomeric molecular structure with the fluorine atoms in trans-position to one another and with the oxygen atoms of the THF molecules in trans to the oxo ligands. [WF4(NCl)(CH3CN)] : Space group P21/m, Z = 2, structure solution with 1119 unique reflections, R = 0.038 for reflections with I > 2σ(I). Lattice dimensions at 20°C: a = 511.7, b = 714.9, c = 1002.5 pm; β = 102.59(10)º. The compound has a monomeric molecular structure in which the nitrogen atom of the acetonitrile molecule coordinates in trans-position to the N-chloro imido group W?N? Cl. The structural parameters of this group are WN = 172.2 pm, NCl = 161.1 pm, WNCl = 178.6º. 相似文献
77.
Michael Plate Sigrid Wocadlo Werner Massa Kurt Dehnicke Harald Krautscheid 《无机化学与普通化学杂志》1995,621(3):388-392
Functionalized Alkyne Complexes of Tungsten(VI). Syntheses and Crystal Structures of [WCl4(Et? Se? C?C? Se? Et)(THF)] and [WCl4(Et? Te? C?C? Te? Et)(THF)] The title compounds have been prepared by reactions of [WCl4(SEt2)2] with the alkynes Et? X? C?C? X? Et (X = Se, Te) in CCl4 solution and subsequent addition of tetrahydrofurane. Both complexes were characterized by crystal structure determinations. [WCl4(Et? Se? C?C? Se? Et)(THF)]: Space group P21/n, Z = 4, structure determination with 2942 unique reflections, R = 0.038. Lattice dimensions at 20°C: a = 934.2, b = 1639.5, c = 1189.5 pm, β = 96.497°. [WCl4(Et? Te? C?C? Te? Et)(THF)]: Space group P21/n, Z = 4, structure determination with 4097 unique reflections, R = 0.067, Lattice dimensions at ?70°C: a = 899.2, b = 1691.9, c = 1213.3 pm, β = 96.82°. The complexes have monomeric molecular structures with the oxygen atom of the THF molecules in trans-position to the side-on bound alkyne ligands. 相似文献
78.
Felora Heshmatpour Dirk Nußhr Ralf Garbe Sigrid Wocadlo Werner Massa Kurt Dehnicke Helmut Goesmann Dieter Fenske 《无机化学与普通化学杂志》1995,621(3):443-450
Syntheses and Crystal Structures of the Phosphorane Iminato Complexes [MCl2(NPPh3)]2 with M = Al and Ga, [SbCl2(NPMe3)(DMF)]2, and of the Phosphorane Imine Complex [Ph3PNH · BF3] · THF The phosphorane iminato complexes [MCl2(NPPh3)]2 with M = Al and Ga and [SbCl2(NPMe3)(DMF)]2 are formed as colourless crystals by reactions of the anhydrous trichlorides MCl3 (M = Al, Ga, Sb) with the corresponding silylated phosphorane imines Me3SiNPR3 in acetonitrile and in dimethyl formamide, respectively. The phosphorane imine derivative [Ph3PNH · BF3] · THF is formed from Me3SiNPPh3 and boron trifluoride etherate in boiling tetrahydrofuran. The compounds are characterized by their i. r. spectra and by crystal structure analyses. [AlCl2(NPPh3)]2 : Space group P1 , Z = 1, structure solution with 1 585 observed unique reflections, R = 0.061. Lattice dimensions at ?70°C: a = 917.6, b = 1 053.5, c = 1 145.2 pm, α = 111.72°, β = 100.80°, γ = 109.95°. [GaCl2(NPPh3)]2 : Space group P1 , Z = 1, structure solution with 2 586 observed unique reflections, R = 0.066. Lattice dimensions at ?70°C: a = 917.5, b = 1 058.3, c = 1 153.7 pm, α = 105.52°, β = 107.75°, γ = 109.88°. In both compounds the metal atoms are linked to planar M2N2 four-membered rings via the N-atoms of the phosphorane iminato groups. [SbCl2(NPMe3)(DMF)]2 : Space group P21/n, Z = 4, structure solution with 3 805 observed unique reflections, R = 0.038. Lattice dimensions at ?70°C: a = 1 913.0, b = 726.8, c = 2 040.7 pm, β = 113.62°. The unit cell contains two symmetry independent dimeric molecules, in which the antimony atoms are centrosymmetricly μ2 linked via the N-atoms of the phosphorane iminato groups. Along with the oxygen atom of the dimethyl formamide molecule the Sb atoms achieve a ψ-octahedral environment. [Ph3PNH · BF3] · THF : Space group C2/c, Z = 8, structure solution with 2 048 observed unique reflections, R = 0.058. Lattice dimensions at ?70°C: a = 2 460.4, b = 869.2, c = 1 978.0 pm, β = 116.35°. 相似文献
79.
Alternative Ligands. XXXII [1]. Novel Tetraphosphane Nickel Complexes with Tripod-Ligands of the Type XM′(OCH2PMe2)n(CH2CH2PR2)3 – n (M′ = Si, Ge; n = 0 – 3) Tripod Ligands of the type XM′(OCH2PMe2)n(CH2CH2PMe23 – n (M′ = Si, Ge; n = 0 – 3) ( 1 – 6 , Table 1) have been used together with PPh3 or PMe3 for the preparation of novel tetraphosphane complexes of Nickel. The representatives LNiPPh3 ( 7 – 12 ) are obtained by reaction of Ni(COD)2 (COD = 1,5-cyclooctadiene) with the corresponding ligands and PPh3 in toluene in moderate yields. The synthesis of the derivatives LNiPMe3 ( 13 – 18 ) is partly ( 16 – 18 ) accomplished in analogy to the Ph3P-complexes; compounds 13 – 16 are obtained in higher yields by reaction of Ni(PMe3)4 with the respective ligand. As a rule, 13 – 18 cannot be separated from by-products. The trinuclear complex FSi(CH2CH2PMe2)3[Ni(PMe2CH2CH2)3SiF]3 ( 19 ) is formed together with 18 in the reaction of Ni(COD)2 with 6 and PMe3. The new compounds have been characterized (if possible) by analytical (C, H), but in general by spectroscopic investigations (IR; 1H-, 13C-, 19F-, 31P-NMR; MS). A weak, but significant Ni → Si interaction through the cage is indicated by the following results: (i) Large low-field shifts δδF of 35.2 ppm ( 12 ), 38.3 ppm ( 18 ) and 37.7 ppm ( 19 ); (ii) 6J(PF) coupling constants [or 3J(PNiSiF) through the cage] of 6.0 Hz ( 12 ) and 7.6 Hz ( 18 ) together with a low-field shift δδSi of 12.8 ppm ( 12 ); (iii) NiSi distances of 3.95 Å in 7 and 3.92 Å in 12 , accompanied by a compression of the cage along the Ni ··· Si axis. An additional release from the high charge density on Ni results from π-backbonding to the phosphane ligands. 相似文献
80.
H.-J. Mai S. Wocadlo H.-C. Kang W. Massa K. Dehnicke C. Maichle-Mssmer J. Strhle D. Fenske 《无机化学与普通化学杂志》1995,621(5):705-712
Phosphanimine and Phosphoraneiminato Complexes of Iron. The Crystal Structures of [FeCl3(Me3SiNPEt3)], [FeCl2(Me3SiNPEt3)]2, [FeCl2(NPEt3)]2, and [Fe(O2C? CH3)2(NPEt3)]2 The phosphanimine complexes [FeCl3(Me3SiNPEt3)] (red-orange) and [FeCl2(Me3SiNPEt3)]2 (colourless) have been prepared by reactions of Me3SiNPEt3 with FeCl3 and FeCl2, respectively, in CH2Cl2 suspensions. Thermal decomposition of these donor-acceptor complexes in boiling toluene leads to the phosphoraneiminato complex [FeCl2(NPEt3)]2 (black), whereas [Fe(O2C? CH3)2(NPEt3)]2 (brown) is formed from iron(II) acetate and Me3SiNPEt3 in boiling acetonitrile. The complexes are characterized by IR spectroscopy and by crystal structure determinations. [FeCl3(Me3SiNPEt3)] (1) : Space group P21/c, Z = 8, structure determination with 4 673 unique reflections, R = 0.033. Lattice dimensions at ?15°C: a = 1 607.8, b = 1 602.0, c = 1 417.2 pm, β = 106.56°. 1 forms monomeric molecules with tetrahedrally coordinated iron atoms. Bond lengths in average: Fe? N = 196.9 pm, Fe? Cl = 219.7 pm. [FeCl2(Me3SiNPEt3)]2 (2) : Space group P21/c, Z = 4, structure determination with 4 992 unique reflections, R = 0.048. Lattice dimensions at 20°C: a = 1 457.9, b = 1 685.4, c = 1 507.3 pm, β = 116.74°. 2 forms dimeric molecules, which are associated by chloro bridges. The iron atoms are tetrahedrally coordinated with trans positions of the phosphanimine ligands. Both lengths in average: Fe? N = 202.2 pm, Fe? Clterminal = 224.7 pm, Fe? Cl bridge = 241.0 pm. [FeCl2(NPEt3)]2 (3): Space group P21/n, Z = 2, structure determination with 2763 unique reflections, R = 0.039. Lattice dimensions at ?70°C: a = 799.1, b = 1009.0, c = 1441.9 pm, β = 93.45°. 3 forms centrosymmetric dimeric molecules, in which the tetrahedrally coordinated iron atoms are associated by the nitrogen atoms of the phosphoraneiminato ligands. Bond lengths in average: Fe? N = 191.4 pm, Fe? Cl = 222.7 pm. [Fe(O2C? CH3)2(NPEt3]2 (4): Space group P21/n, Z = 2, structure determination with 3005 observed unique reflections, R = 0.034. Lattice dimensions at -65°C: a = 886.4, b = 1444.6 pm, β = 90.60°. 4 forms centrosymmetric dimeric molecules, in which the octahedrally coordinated iron atoms are associated by the nitrogen atoms of the phosphoraneiminato ligands with bond lengths Fe? N of 191.9 and 195.0 pm. The acetate groups are coordinated in a chelating fashion. 相似文献