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91.
《Journal of Coordination Chemistry》2012,65(11):1820-1826
Mononuclear O,O-coordinated complexes K2(MLCl2) M = Zn(II), Cd(II) and dinuclear complexes (MZnLCl2R2)x along with dinuclear N,N-coordinated complexes (M′ZnH2LCl2R2)y (where M = Zn(II), Cd(II), Hg(II) and M′ = M and Sn(IV); R = Cl, CH3; x = 0, ?2; y = 0, +2) of N′-1-,N′-2-dihydroxy-N-1-,N-2-dipyridin-2-ylethanedimidamide (H2L) have been prepared. All complexes have been characterized by 1H NMR, IR, EI-mass spectroscopy and elemental microanalysis. These results are in agreement with our prediction for structures of mono and dinuclear complexes of H2L and L?2 with Zn(II) in the gas phase by theoretical studies. 相似文献
92.
《Journal of Coordination Chemistry》2012,65(16):2728-2735
A new Schiff base, {1-[(2-hydroxy-naphthalen-1-ylmethylene)-amino]-4-phenyl-2-thioxo-1, 2-dihydro-pyrimidin-5-yl}-phenyl-methanone, has been synthesized from N-amino pyrimidine-2-thione and 2-hydroxynaphthaldehyde. Metal complexes of the Schiff base were prepared from acetate/chloride salts of Cu(II), Co(II), Ni(II), Zn(II), and Cd(II) in methanol. The chemical structures of the Schiff-base ligand and its metal complexes were confirmed by elemental analyses, IR, 13C-NMR, 1H-NMR, API-ES, UV-Visible spectroscopy, magnetic susceptibility, and thermogravimetric analyses. The electronic spectral data and magnetic moment measurements suggest mononuclear octahedral and mononuclear or binuclear square planar structures for the metal complexes. In light of these results, it was suggested that this ligand coordinates to each metal atom by hydroxyl oxygen, azomethine nitrogen, and thione sulfur to form octahedral complexes with Cd(II) and Zn(II). 相似文献
93.
《Journal of Coordination Chemistry》2012,65(5):868-883
The reaction of copper(II) salts with (E)-N-(2-hydroxy-1,2-di(pyridin-2-yl)ethylidene)aroyl hydrazide (H2L1, H2L2, H3L3) or (E)-N-(2-hydroxy-1,2-di(pyridin-2-yl)ethylidene) isonicotinohydrazide (H2L4) afforded the complexes [(L)Cu(H2O)3], [(H2L)Cu(OAc)(H2O)], [(HL)Cu(OAc)] n , [(H2L)Cu(H2O)](ClO4)2 and [(H2L)Cu(OAc)(H2O)], where n = 1 or 2 and L is the dinegative ion of the ligands. The ligands and their complexes are characterized by elemental analyses, spectral (IR, NMR, electronic, and ESR) and magnetic studies. The FT-IR indicates that the ligands are neutral or anionic polydentate. The number of the coordinating centers depends on the nature of the metal used and the reaction conditions. The room temperature magnetic moment values, electronic spectra and ESR data indicate square planar, trigonal bipyramidal, square pyramidal, and distorted octahedral ligand fields around copper(II). Thermal decomposition of the complexes was monitored by TG and DTG under N2 and the thermal decomposition mechanisms are given. The compounds were screened for their antimicrobial activities on some Gram-positive and Gram-negative bacterial species. The free ligands are inactive against all studied bacteria. The complexes have variable activity with the most active [(H2L)Cu(H2O)](ClO4)2, where H2L is H2L1 or H2L2. The minimum inhibition concentrations for these two complexes were determined. These biological activity results are related to the structures of the compounds. 相似文献
94.
95.
Preparation and Crystal Structures of Silver(I) Mixed Ligand Complexes with Bibenzimidazole and Triphenylphosphane: [Ag(PPh3)2(bbimH2)](COOCH3) · 2 CH2Cl2 and [{Ag(PPh3)2}2(μ-bbim)] · 4 CH2Cl2 The title compounds are obtained from silver acetate, 2,2′-bibenzimidazole and PPh3. They are characterized by their IR, 1H-NMR, 31P-NMR spectra and crystal structure determinations. [Ag(PPh3)2(bbimH2)](COOCH3) · 2 CH2Cl2: Reaction in CH2Cl2. Space group C2/c, Z = 4, 3129 observed unique reflections, R = 0.033. Lattice parameters at 203 K: a = 1450.8; b = 1556.2; c = 2316.4 pm; β = 99.69°. The crystal structure is built up by monomeric molecules with distorted tetrahedral coordination of the silver atom (AgP2N2) and bibenzimidazole as a bidentate ligand. The acetate ion is linked to the NH-groups of the bibenzimidazole by hydrogen bonds. [{Ag(PPh3)2}2(μ-bbim)] · 4 CH2Cl2: Reaction in fused PPh3 at 180 °C. Space group P 1, Z = 1. 9227 observed unique reflections, R = 0.051. Lattice parameters at 203 K: a = 1276.5; b = 1352.1; c = 1408.1 pm; α = 96.97; β = 115.87; γ = 96.84°. The crystal structure is built up by centrosymmetric molecules with distorted tetrahedral coordination of the silver atoms (AgN2P2) and bibenzimidazolate(2–) as tetradentate bridging ligand. 相似文献
96.
Binuclear Antimony(V) Complexes with Bridging Diphenylphosphato Ligands The binuclear antimony(V) complexes Cl3Sb(O)[(C6H5O)2PO2]2SbCl3 ( 1 ), Cl3Sb(O)[(C6H5O)2PO2](OCH3)SbCl3 ( 2 ), Cl3Sb(O)[(C6H5O)2PO2](OH)SbCl3 ( 3 ) and Cl4Sb[(C6H5O)2PO2]2SbCl4 ( 4 ) are prepared by reaction of diphenylphosphoric acid with antimony(V) chloride, water and methanol in different molar ratios. The progress of the reactions was controlled by the 31P-NMR signals. 1 crystallizes triclinic in the space group P1 with a = 918.8, b = 1312.9, c = 1395.8 pm, α = 91.91, β = 101.36, γ = 95.90° and Z = 2. 2 to 4 crystallize in monoclinic space groups: 2 : C2/c, a = 2753.4, b = 1156.1, c = 1476.7 pm, β = 98.01° and Z = 8; 3 : P21/c, a = 1234.8, b = 1471.8, c = 1263.4 pm, β = 107.15° and Z = 4; 4 : P21/n, a = 1943.8, b = 940.8, c = 2015.6 pm, β = 109.87° and Z = 4 resp. The NMR spectra are discussed and some IR data are communicated. 相似文献
97.
Reaction of tert -Butyl-phosphaalkyne with Molybdenum Complexes The reaction of tBuC≡P with [(CH3CN)3Mo(CO)3] leads to the complex [Mo(CO)4〈Mo(CO)2(η4-P3CtBu){η4-P2(CtBu)2}〉] 1 as well as to the alkyne complexes [Mo(CO)4〈{P3(CtBu)2}{Mo(CO)2(CtBu)}{η3-P2(CtBu)2}〉] 2 and [Mo(CtBu){η4-P2(CtBu)2(CO)}{η5-P3(CtBu)2}] 3 . All compounds are characterized by X-ray structural analysis, by NMR- and IR spectroscopy and by mass spectrometry. In complex 1 a 1,3-diphosphacyclobutadiene and a 1,2,4-triphosphacyclobutadiene are connected by two molybdenum carbonyl centres. In 2 a 1,3-diphosphacyclobutadiene is π- and a novel 1,2,4-triphospholyl ligand is σ-bonded at two Mo centres. A characteristic feature of 3 besides a π co-ordinated 1,2,4-triphospholyl ligand is a 3,4-diphosphacyclopentadienone as ligand, formed via CO insertion during the cyclodimerisation of two phosphaalkynes. 相似文献
98.
Synthesis, Structure, and Photolysis of Isocyanato Complexes of Rhenium The ReIII isocyanato complex Re(NCO)3(PMe2Ph)3 yields from the reaction of ReCl3(PMe2Ph)3 with an excess of NaOCN in EtOH. It crystallizes in the triclinic space group P 1 with a = 991.8(6), b = 1180.7(6), c = 1348.8(5) pm, α = 89.85(1)°, β = 94.12(1), γ = 111.56(1)°, Z = 2. In the mononuclear complex with an octahedral coordination of the Re atoms the phosphine and isocyanato ligands exhibit a meridional arrangement. By using a deficient amount of NaOCN the mono isocyanato complex Re(NCO)Cl2(PMe2Ph)3 is formed, and part of the educt is transformed to its isomer [(Me2PhP)3Re(μ-Cl)3Re(PMe2Ph)3]Cl3. The mono isocyanato complex forms monoclinic crystals with the space group P21/n and a = 1467.5(7), b = 1310.6(7), c = 1603.2(8) pm, β = 112.08(1)°, Z = 4. The isocyanato ligand is in trans position to a Cl atom, and the phosphine ligands are coordinated in a meridional arrangement. [(Me2PhP)3Re(μ-Cl)3Re(PMe2Ph)3]Cl3 · 2 EtOH crystallizes in the hexagonal space group P63/m with a = 1332.6(2), c = 2300.1(7) pm, Z = 2. The dinuclear complex cation occupies with its center a special position with the symmetry C3h. Photolysis of Re(NCO)Cl2(PMe2Ph)3 results in the cleavage of the isocyanato ligand with release of CO and formation of the nitrido complex ReNCl2(PMe2Ph)3. The reaction of ReNCl2(PMe2Ph)3 with NaOCN affords the complex ReN(NCO)2(PMe2Ph)3. It crystallizes in the space group P21/n with a = 943.0(3), b = 2635.2(4), c = 1212.6(5) pm, β = 109.88(1)°, Z = 4. In this nitrido complex, like in the educt, the phosphine ligands form a meridional arrangement. The nitrido ligand is in trans position to an isocyanato group. The distance Re≡N is 165.9(6) pm. 相似文献
99.
Miraç Ocak Nurhan Gümrükçüoğlu Ümmühan Ocak Hans-Jurgen Buschmann Eckard Schollmeyer 《Journal of solution chemistry》2008,37(11):1489-1497
Six new triazole compounds were synthesized. These compounds containing the substituted benzylidenamino group were obtained
by reaction of 3-(pyridine-4-yl)-5-p-tolyl-4-amino-4H-l,2,4-triazole 1 with the corresponding aldehyde. The reduced forms were prepared with NaBH4 in methanol. The structures of the compounds were determined by IR, 1H NMR, and 13C NMR spectral data, and their interaction with cations such as Li+, Na+, K+, Rb+, Cs+, Ba2+, Sr2+, Ca2+, Cu2+, Cr3+, Co2+, Ni2+, Zn2+, Cd2+, Pb2+ and Ag+ were investigated by using UV-visible spectrophotometry. Of the tested metal cations, Cu2+, Cr3+, Co2+, Ni2+, Zn2+, Cd2+, Pb2+ and Ag+ complexed with the ligands. The complex stability constants (log 10
K) were measured in slightly acidic aqueous media at 25.0±0.1 °C. These stability constants were determined by measuring the
increase in solubility of the nearly insoluble ligand molecule due to complex formation with a soluble cation, and this method
is discussed. It was found that the position of chlorine atoms on the benzene ring strongly affects the complexation of Cu2+ ion with these ligands. 相似文献
100.