共查询到20条相似文献,搜索用时 15 毫秒
1.
Zinc(II) and mercury(II) complexes were prepared by reacting isatin-3-thiosemicarbazone (ISTSCH) with zinc(II) acetate or mercury(II) bromide. The complexes were characterized by IR, Raman, diffuse reflectance, 1H and 13C NMR spectra and elemental analysis. Tetrahedral structures for Zn(ISTSC)2 and Hg(ISTSCH)Br2 are suggested. 相似文献
2.
《Journal of Coordination Chemistry》2012,65(14):1251-1262
Formation of ternary Cd(II) and Hg(II) complexes with cytidine 5′-monophosphate (CMP) and triamines has been studied. Complexes M(CMP)(H x PA) and M(CMP)(PA) (M?=?Cd, Hg; PA?=?polyamine) were detected and overall stability constants and equilibrium constants for their formation determined. The mode of coordination in the complexes has been proposed on the basis of the equilibrium and 13C, 31P NMR and IR studies. In the Hg(II) systems, metalation involves the donor endocyclic N(3) atom, the CMP phosphate group and nitrogen donor atoms of PA. Relative to the Hg/CMP binary systems, the presence of a polyamine in ternary systems does not change the metal–nucleotide mode of coordination. In ternary systems including Hg(II) ions, the occurrence of noncovalent interactions has not been detected. Cd(II) ions form molecular complexes as well as protonated species. Introduction of a polyamine to the Cd/CMP system changes the coordination mode of the nucleotide. The phosphate group of CMP is inactive in binary complexes (metalation by the N(3) atom) but is involved in coordination in heteroligand species. In contrast to other polyamines studied, in the system including 1,7-diamino-4-azaheptane (3,3-tri), the phosphate group of CMP in Cd(CMP)(H3,3-tri) does not participate in metalation but is engaged in intramolecular noncovalent interactions that stabilize the complex. 相似文献
3.
Neat reaction between HgI2 and 1-methyl-2-(phenylazo)imidazole (Pai-Me) under microwave irradiation has isolated a novel compound whose structure shows intercalated HgI2 in the layers of Pai-Me. They exist independently in interpenetrated arrays. In a solution phase study, the same reaction has synthesized an iodo-bridged azoimidazole-Hg(II) complex, [Hg(RaaiR')(mu-I)(I)]2 (RaaiR' = 1-alkyl-2-(arylazo)imidazole). The structures have been characterized by X-ray diffraction studies. Chloro-bridged Hg(II) complexes of azoimidazoles, [Hg(RaaiR')(mu-Cl)(Cl)]2, are also known. These complexes upon irradiation with UV light show trans-to-cis isomerization. The reverse transformation, cis-to-trans isomerization, is very slow with visible light irradiation. Quantum yields (phi t-->c) of trans-to-cis isomerization are calculated, and the free ligand shows higher phi than their Hg(II) complexes. The cis-to-trans isomerization is a thermally induced process. The activation energy (Ea) of cis-to-trans isomerization is calculated by controlled temperature reaction. The Ea's of free ligands are much higher than that of halo-bridged Hg(II)-azoimidazole complexes. Chloro-bridged Hg(II) complexes show lower Ea's than those of iodo-bridged complexes. DFT calculation has been adopted to rationalize the experimental results. 相似文献
4.
The reactions of the title ylide {(C6H5)3PCHCOC6H4OCH3)} (MBPPY) with mercury(II) chloride and mercury(II) bromide in equimolar ratios using methanol as the solvent produces crystals of [(MBPPY) · HgCl2]2 (1) and [(MBPPY) · HgBr2]2 (2), respectively. Single crystal X-ray analyses reveal the presence of centrosymmetric dimeric structures containing the ylide and HgX2 (X = Cl or Br) in both cases. The IR and NMR data of the product [(MBPPY) · HgI2]2 (3), formed by the reaction of mercury(II) iodide with the same ylide, are similar to those of 1 and 2. Analytical data indicate a 1:1 stoichiometry between the ylide and Hg(II) halide in each of the three products. 相似文献
5.
Jozef Svorec Štefan Lörinc Jan Moncol Milan Melník Marian Koman 《Transition Metal Chemistry》2009,34(7):703-710
The synthesis and characterization of four new solid complexes, Cu(tolf)2L2 (tolf = tolfenamate, L = 2-pyridylmethanol (2-pyme), 3-pyridylmethanol (3-pyme), nicotinamide (na)) and Cu(tolf)2(dena)2(H2O)2 (dena = N,N-diethylnicotinamide) is reported. The composition and stereochemistry as well as the mode for ligand coordination have been determined by elemental analysis, IR, electronic and EPR spectra. The carboxyl group of the tolfenamate anion coordinates to the Cu(II) atom as an unidentate or as a chelating ligand. The EPR spectra of the powdered solids are consistent with spin S = ½. The crystal structure of Cu(tolf)2(dena)2(H2O)2 has been determined at 293 K. The Cu(II) atom has a tetragonal–bipyramidal arrangement (CuO4N2). The spectroscopic data indicate that each copper(II) atom in Cu(tolf)2L2 has a tetragonal–bipyramidal environment built up by bidentate unsymmetrically coordinate tolfenamates and unidentate N-donor atom ligands. 相似文献
6.
A solid-phase microextraction method coupled with a flame photometric detector was developed for the analysis of organophosphorus pesticides in water. Two kinds of fiber (100 mum polydimethyl siloxane (PDMS) and 85 mum polyacrylate (PA) fibers) were used and compared. Parameters that may affect the extraction, such as the duration of absorption and desorption, temperature of absorption, ionic strength, elutropic strength, and concentration of humic acid were investigated. Higher sensitivity and lower detection limits were achieved using a PA fiber than using a PDMS fiber. The detection limit is less than 0.3 mug l(-1) for most of the analytes, except for mevinphos (420 mug l(-1)). The precision is better than 9%. 相似文献
7.
The azide ligand has been receiving intense attention in the rapid growth of literature in the field of molecular magnetism. Primarily, azide ion functions as a bridging ligand and magnetic coupler of paramagnetic metal ions. This review is centered on the study of diverse structural and magnetic properties of copper(II) azido complexes. Some of the trends identified could serve as a privileged starting point for the further development of this promising area. 相似文献
8.
Goldcamp MJ Edison SE Squires LN Rosa DT Vowels NK Coker NL Krause Bauer JA Baldwin MJ 《Inorganic chemistry》2003,42(3):717-728
A library of tripodal amine ligands with two oxime donor arms and a variable coordinating or noncoordinating third arm has been synthesized, including two chiral ligands based on l-phenylalanine. Their Ni(II) complexes have been synthesized and characterized by X-ray crystallography, UV-vis absorption, circular dichroism, and FTIR spectroscopy, mass spectrometry, and room-temperature magnetic susceptibility. At least one crystal structure is reported for all but one Ni/ligand combination. All show a six-coordinate pseudo-octahedral coordination geometry around the nickel center, with the bis(oxime)amine unit coordinating in a facial mode. Three distinct structure types are observed: (1) for tetradentate ligands, six-coordinate monomers are formed, with anions and/or solvent filling out the coordination sphere; (2) for tridentate ligands, six-coordinate monomers are formed with Ni(II)(NO(3))(2), with one monodentate and one bidentate nitrate filling the remaining coordination positions; (3) for tridentate ligands, six-coordinate, bis(mu-Cl) dimers are formed with Ni(II)Cl(2), with one terminal and two bridging chlorides filling the coordination sphere. The UV-vis absorption spectra of the complexes show that the value of 10 Dq varies according to the nature of the third arm of the ligand. The trend based on the third arm follows the order alkyl/aryl < amide < carboxylate < alcohol < pyridyl < oxime. 相似文献
9.
Lee D DuBois JL Pierce B Hedman B Hodgson KO Hendrich MP Lippard SJ 《Inorganic chemistry》2002,41(12):3172-3182
The synthesis, molecular structures, and spectroscopic properties of a series of valence-delocalized diiron(II,III) complexes are described. One-electron oxidation of diiron(II) tetracarboxylate complexes afforded the compounds [Fe(2)(mu-O(2)CAr(Tol))(4)L(2)]X, where L = 4-(t)BuC(5)H(4)N (1b), C(5)H(5)N (2b), and THF (3b); X = PF(6)(-) (1b and 3b) and OTf(-) (2b). In 1b-3b, four mu-1,3 carboxylate ligands span relatively short Fe...Fe distances of 2.6633(11)-2.713(3) A. Intense (epsilon = 2700-3200 M(-1) cm(-1)) intervalence charge transfer bands were observed at 620-670 nm. EPR spectroscopy confirmed the S = (9)/(2) ground spin state of 1b-3b, the valence-delocalized nature of which was probed by X-ray absorption spectroscopy. The electron delocalization between paramagnetic metal centers is described by double exchange, which, for the first time, is observed in diiron clusters having no single-atom bridging ligand(s). 相似文献
10.
p-Anisaldehyde thiosemicarbazone (PAT) has been used to isolate the complex compounds of the general formula [M(PAT)X2]H2O where M(II) = Zn, Hg, Cd and Cu, and X = Cl or SO4. Probable structures for the complex compounds have been proposed on the basis of elemental analysis, conductometric, spectral and magnetic susceptibility data. The toxicity of the isolated complexes and ligand has been evaluated on pathogenic fungus. 相似文献
11.
D. Carmona R. Thouvenot L.M. Venanzi F. Bachechi L. Zambonelli 《Journal of organometallic chemistry》1983,250(1):589-608
The mono-hydrido-bridged complexes (PEt3)2(Ar)Pt(μ2-H)Pt(Ar)(PEt3)2]-[BPh4] (Ar = Ph, 4-MeC6H4 and 2,4-Me2C6H3) have been obtained by treating trans-[Pt(Ar)(MeOH)(PEt3)2][BF4] with sodium formate and Na[BPH4]. The cations [PEt3)2(Ar)Pt(μ2-H)Pt(Arb')(PEt3)2]b+ (Ar = Ph and Arb' - 2,4-Me2C6H3 and 2,4,6-Me3C6H2 have bee identified in solution. Their b1H- and b31P-NMR data are reported. The X-ray crystal structure of [(PEt3)2(Ph)Pt(μ2-H)Pt(Ph)(PEt3)2][BPh4] is reported. 相似文献
12.
Godoy Netto Adelino V. Frem Regina C.G. Mauro Antonio E. Santos Regina H.A. Zoia Jussara R. 《Transition Metal Chemistry》2002,27(3):279-283
Mononuclear palladium(II) complexes containing both pyrazole-type ligands and thiocyanate, of general formula [Pd(SCN)2(L)2] {L = pyrazole (HPz) and 1-phenyl-3-methylpyrazole (phmPz)} have been prepared and characterized by elemental analysis, i.r. and n.m.r. spectroscopy and by single crystal X-ray diffraction methods. The Pd atom in these structures lies on the crystallographic inversion center; in a square-planar coordination geometry made by two sulfur and two nitrogen atoms of the ligands, both in trans positions. 相似文献
13.
Aziza K. Shehata Gamila Y. Ali Amina A. Soayed Ali El-Dissouky 《Transition Metal Chemistry》1996,21(2):117-122
Summary (4,5-Dimethyl-3-pyrazolyl)aldazine, L, reacts with nickel(II) salts to form 11 and 12 complexes. The 11 binuclear systems involve two ligands bridging two nickels, in which L behaves as a tetradentate ligand, and the nickel(II) complexes have pseudo-octahedral stereo-chemistry. Some of the 11 and 12 complexes contain coordinated H2O and bridging OH. Structures of these complexes are proposed on the basis of elemental analyses, conductivity, spectral data (u.v.-vis. and i.r.) and magnetic susceptibilities. 相似文献
14.
15.
Ramadan M. El-Bahnasawy El-Sayed El-Shereafy Tahani I. Kashar Yousry M. Issa 《Transition Metal Chemistry》1995,20(2):104-106
Summary Copper(II) phenylhydrazoacetylacetone isonicotinoyl hydrazone complexes were prepared at two different pHs and characterized by elemental analysis and various physical techniques. In neutral solutions monoligand complexes (1) and (2) were obtained, but the bisligand complex (3) was obtained from solution at pH 10. The ligand H2L behaved either as monobasic bidentate or dibasic tridentate towards cupric ions. Magnetic and spectral data suggest square planar structures for [CuL·H2O]·H2O but an octahedral structure for [Cu(HL)2·2H2O]·3H2O.Author to whom all correspondence should be directed. 相似文献
16.
《Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy》1978,34(7-8):667-671
The following rhodanine (HRd) complexes of zinc(II), cadmium(II), mercury(II) and mercury(I) have been prepared and studied by i.r. spectra: M(Rd)2(NH3)2 (MZn, Cd) with a 4N,2S-six-coordination; Zn3(Rd)4(CH3COO)(OH), Cd2(Rd)3(HRd)3(CH3COO)(H2O) in which the acetato anion is bicoordinated; Hg(Rd)2, Hg2(HRd)3(BF4)2·0.5(HAc or EtOH), Hg(HRd)(CF3COO)2·H2O in which both the ligands HRd and Rd− are S,N-bonded to the metal; Hg(HRd)2Cl2, Hg(HRd)4(ClO4)2 in which the ligand HRd is S-bonded; Hg3(Rd)3 · NH3 with S,N-bonded Rd− ligand. 相似文献
17.
Novel complexes of tris(aminomethyl)phosphanes with platinum(II): Structural, spectroscopic, DFT and biological activity studies 总被引:1,自引:0,他引:1
Rados?aw Starosta Aleksandra BykowskaMaciej Barys Anna K. WieliczkoZdzis?aw Staroniewicz Ma?gorzata Je?owska-Bojczuk 《Polyhedron》2011,30(17):2914-2921
Two new platinum(II) complexes with tris(aminomethyl)phosphanes: [trans-PtCl2{P(CH2N(CH2CH2)2NCH3)3}2] (1Pt) and [trans-PtCl2{P(CH2N(CH2CH2)2O)3}2] (2Pt) were prepared and characterized with NMR and UV-Vis spectroscopies. Their structures were investigated by X-ray crystallography and DFT methods. TDDFT calculations were employed to interpret the electronic spectra of the complexes. Obtained results are not unequivocal, however population analysis indicate, that the character of HOMO and HOMO−1 orbitals depend strongly on the electron donoring properties of the phosphane ligand. Biological activity of 2Pt complex, which is more stable and more soluble in polar solvents than 1Pt, was examined in vitro on the Vero cell line (IC50 = 12.5 μM). At higher concentrations it induces apoptosis, probably due to changes of the cell cytoskeleton. Luminescence quenching studies and CD spectroscopy of interactions of 2Pt with HSA and BSA indicate that these albumins bind the complex slightly - without altering their tertiary structures, however HSA interacts with 2Pt noticeably stronger than BSA. It was also found that 2Pt does not cleave supercoiled pUC18 plasmid. 相似文献
18.
19.
20.
Agnieszka Pladzyk Joanna Olszewska Katarzyna Baranowska Anna Maria Dziurzyńska 《Transition Metal Chemistry》2010,35(7):821-827
Cobalt(II) tri-tert-butoxysilanethiolates with 2,5-dimethylpyridine, 3,4-dimethylpyridine and 3,5- dimethylpyridine co-ligands have been synthesized
by reaction of bimetallic [Co{μ-SSi(O
t
Bu)3}{SSi(O
t
Bu)3}(NH3)]2 with the appropriate pyridines. The complexes were characterized by elemental analysis, single-crystal X-ray structure determination,
IR and UV–Vis spectroscopy. These complexes are tetra- or penta-coordinated with CoN2S2 and CoNO2S2 cores, respectively. 相似文献