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1.
Lewis K. Panell Henry M. Fales John P. Scovill Daniel L. Klayman Douglas X. West Ramon L. Tate 《Transition Metal Chemistry》1985,10(4):141-147
Summary Californium-252 plasma desorption mass spectra were recorded for complexes of the anions of various thio-and seleno-semicarbazones of 3-acetylpyridines(1–4) with the transition metal ions iron(III) and cobalt(II). Positive ion spectra gave clear evidence of the cation present and fragmentation with loss of ligands or parts of ligands was straightforward. Negative ion spectra likewise provided evidence of the intact anion except with tetracoordinate metal halide systems [MX4]– which lost one or more halide atoms. Evidence of fragmentation of the ligand and recombination of the fragments with the metal ion was also observed in the negative ion mode. Spectra were used to revise the structure of a complex previously reported as [FeLCl2](1) to [FeL2]+[FeCl4]–. 相似文献
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Sunhong Park Shim Sung Lee 《Journal of inclusion phenomena and macrocyclic chemistry》2011,71(3-4):429-434
Two isomeric NS2-macrocycles incorporating a xylyl group at ortho (o -L) and meta (m -L) positions were employed and their copper complexes (1?C5) were prepared and structurally characterized. The copper(II) nitrate complexes [Cu(L)(NO3)2] (1: L = o -L, 2: L = m -L) for both ligands were isolated. In each case, the copper center is five-coordinated with a distorted square pyramidal geometry. Despite the overall geometrical similarity, 1 and 2 show the different ligand conformation due to the discriminated packing pattern. Reaction of o -L with copper(II) perchlorate afforded complex 3 containing two independent complex cations [Cu(o -L)(H2O)(DMF)(ClO4)]+ and [Cu(o -L)(H2O)(DMF)]2+; the coordination geometry of the former is a distorted octahedron while the latter shows a distorted square pyramidal arrangement. In the reactions of copper(I) halides (I or Br), o -L gave a mononuclear complex [Cu(o-L)I] (4) with a distorted tetrahedral geometry, while m -L afforded a unique exodentate 2:1 (ligand-to-metal) complex [trans-Br2Cu(m-L)2] (5) adopting a trans-type square-planar arrangement. 相似文献
3.
Seleem HS Mostafa M Hanafy FI 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2011,78(5):1560-1566
The stability constants of three isomeric quinolyl hydrazones; {4,6-(para); 4,7-(meta) and 4,8-MeBHQ(ortho)} towards some bivalent metal ions have been determined in 75% solvent (dioxane, isopropanol, ethanol and methanol)-water by a pH-titrimetry. The insertion of the Me-group in the 8-position decreases the stability of the complexes to a great extent. The complexation of the ortho-derivative is endothermic, whereas that of the para-derivative is exothermic. Using the solvent parameters, the stability constants of the para-derivative towards Co(II), Ni(II) and Cu(II) ions were evaluated in aqueous medium by five different methods. Also, the electronic absorption spectra of the ortho-hydrazone have been studied in solvents of various polarities to investigate the dependence of the band shift (Δ?) on the solvent parameters viz. 1/D, Z, E(T), DN, AN and (α, β, π*). The interaction of the hydrazones with CoCl(2)·6H(2)O afforded an octahedral complex in case of the ortho-hydrazone and square planar complexes in case of the meta- and para-hydrazones. 相似文献
4.
Ring currents induced in the ferrocene molecule and its two hypothetical isomers (η4-C4H4)Fe(η6-C6H6) and (η3-C3H3)Fe(η7-C7H7) by an external magnetic field directed along the principal axis are plotted within the ipsocentric approach (at the B3LYP/6-31G∗∗//B3LYP/6-31G∗∗ level). The carbocyclic ligands in all three species are found to be aromatic, i.e. to support individual diatropic ring currents, with formal charges that are consistent with the 4n + 2 rule and the +2 oxidation state of iron. 相似文献
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Siedle AR Webb RJ Behr FE Newmark RA Weil DA Erickson K Naujok R Brostrom M Mueller M Chou SH Young VG 《Inorganic chemistry》2003,42(4):932-934
Triazapentadienides, C(3)F(7)-C(=NR)-N=C(NHR)-C(3)F(7), result from the reaction of primary amines RNH(2) with the fluorinated imine C(3)F(7)-CF=N-C(4)F(9). The aniline derivative (R = Ph) is a weak monoprotic acid in dmso. Its conjugate base exhibits an extensive coordination chemistry. It acts as a bidentate ligand toward the molecular fragments Pd(C(3)H(5)), Rh(c-C(8)H(12)), Ir(c-C(8)H(12)), and Rh(CO)(2). The chelates [C(3)F(7)-C(NPh)-N-C(NPh)-C(3)F(7)](2)M, M = Mg, Mn, Fe, Co, Ni, Cu, Zn, and Pd, were prepared. In the crystallographically characterized Co complex, the metal is 3d(7), S = (3)/(2) and tetrahedrally coordinated. Spin densities at carbon in the C(6)H(5) and C(3)F(7) groups were estimated from the (1)H and (19)F contact shifts. Spin delocalization onto phenyl sp(2) carbons is approximately 10 times greater than onto the fluorinated sp(3) carbons. 相似文献
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Pairs of isomeric heterodinuclear complexes, [(cod)Ir(mu-PNNN)M(L)]BF4 and [(L)M(mu-PNNN)Ir(cod)]BF4, with switched metal arrangements are prepared in a specific manner by simply changing the addition order of the reagents. 相似文献
8.
Fogel Y Kastler M Wang Z Andrienko D Bodwell GJ Müllen K 《Journal of the American Chemical Society》2007,129(38):11743-11749
The selective oxidation of the perimeter of an extended polycyclic aromatic hydrocarbon (PAH), namely a six-fold tert-butylated tetrabenzo[bc,ef,hi,uv]ovalene, led to the formation of an alpha-diketone. The newly installed carbonyl centers allowed this building block to be converted into the largest known heteroatom-containing PAHs (up to 224 atoms in the aromatic core) by way of the quinoxaline ring condensation reaction. The tert-butyl substituents caused a distortion of the usually planar aromatic frameworks, which hampered the aggregation tendency of the extended aromatic pi-systems and led to extraordinarily high solubilities. All of the systems described here, even the giant phthalocyanine, could thus be purified using standard chromatographic techniques and characterized using typical spectroscopic methods. For the first time, fully resolved 1H NMR spectra of soluble, diamagnetic, 98- and 104-atom-containing aromatic systems are presented. The computed and experimental UV/vis spectra emphasize the dependence of the characteristic alpha-, p-, and beta-bands upon the size of the PAHs. It was also possible to obtain the largest known ligand to yet be complexed around a ruthenium center. A quadrupolar solvatochromic effect was observed when two donating PAH moieties were fused to an accepting quinoxaline center, in which case the photoluminescence spanned a range of about 80 nm. Electrochemical properties of the new nanographenes were investigated using cyclic voltammetry, and this showed quasi-reversible reductions. 相似文献
9.
四苯骈卟啉及其金属配合物的合成 总被引:1,自引:0,他引:1
卟啉类化合物作为电子给体在光合作用模拟研究中占据着重要位置 ,在卟啉环上引入供电子基团以增大共轭体系 ,常有利于卟啉环的给电子作用 ,过去常用的卟啉化合物为四苯基卟啉及其衍生物 ,但由于空阻作用 ,四个亚甲基上的苯基不能很好与卟啉环共平面而降低了共轭效应 ,为了寻求一种更有利于卟啉环共轭大Π键形成的结构 ,我们合成了比四苯基卟啉共平面效果更好的卟啉化合物———四苯骈卟啉 (H2 TBP)及其与Ni2 + 、Co2 + 、Zn2 + 的金属配合物以及研究它的给电子作用效果。四苯骈卟啉配合物早在 1 92 8年就为人们所认识[1] ,但其研… 相似文献
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Emanuel Vogel 《Journal of heterocyclic chemistry》1996,33(5):1461-1487
The cornucopia of novel porhyrinoid macrocycles that - as a result of a symbiotic link between annulene and porphyrin chemistry - has emerged from the Cologne laboratory over the last decade is reviewed. 相似文献
12.
M. B. Ummathur 《Journal of the Iranian Chemical Society》2007,4(2):244-255
A new series of unsaturated polycarbonyl compounds in which the keto group attached to olefinic linkage has been synthesized by the reaction of acetoacetanilide and aromatic aldehydes under specified conditions. The existence of these compounds predominantly in the intramolecularly hydrogen bonded enol form has been well demonstrated from their IR, 1H NMR and mass spectral data. Details on the formation of their complexes with Ni(II), Cu(II), and Zn(II) and their nature of bonding are discussed on the basis of analytical, IR, 1H NMR and mass spectral data. 相似文献
13.
V. A. Kogan S. I. Levchenkov L. D. Popov I. A. Shcherbakov 《Russian Journal of General Chemistry》2009,79(12):2767-2775
Structure, tautomeric rearrangements, acid-base properties and complex formation ability of 1-hydrazinophthalazine hydrazones
and their coordination compounds with transition metals are considered. The main factors influencing the structure and physicochemical
properties of the complexes, biological activity of phthalazine hydrazones and their complexes are discussed. 相似文献
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Shaya Y. Al‐Raqa Ahmed M. Sh. ElSharief Saied M. E. Khalil Abdulkhaliq M. Al‐Amri 《Heteroatom Chemistry》2006,17(7):634-647
Halogenated imidazo(pyrazine,[1,4]diazocine and quinoxaline), 9,10‐anthraquinone‐ [6,7‐e], phenanthroline[5,6‐e] {imidazo[4,5‐b]pyrazine}, and naphtho[1,8‐ef]imidazo[4,5‐b][1,4] diazipen were obtained through interaction of imidazolidineiminothiones with the corresponding diamino compounds. Imidazo[4,5‐e] triazine and pyrrolo[2,3‐d]imidazole were prepared when the iminothiones were reacted with thiocarbohydrazide and with ethylphenyl acetate, separately. Some of the synthesized compounds exhibited better biological and antitumor activities. © 2006 Wiley Periodicals, Inc. Heteroatom Chem 17:634–647, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20244 相似文献
16.
Kyu Suk Choi 《Macromolecular Symposia》1990,33(1):55-63
Thiosemicarbazide, phosphoric acid and amidoxime derivatives of chitosan were synthesized and their ability for metal ion adsorptions was discussed. Thiosemicarbazide derivative, synthesized by treating chlorodeoxychitosan with ammonium thiocyanate followed by treatment with hydrazine, was considered to have cross-linked network structure. Phosphoric acid derivative containing both N-phosphonic acid and phosphoric acid groups was synthesized by cyanoethylation of chitosan using acrylonitrile, followed by treatment with hydroxylamine. These derivatives were found to adsorb effectively infinitesimal concentration (ppb order) of uranyl ion in seawater. Stability constants of some metal ion chitosan chelates were determined. To improve the selectivity in the adsorption of metal ions, a novel method utilizing metal ion as a template was adopted, and the results are discussed. 相似文献
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Vlasov P. S. Kiselev A. A. Domnina N. S. Popova E. V. Tyuterev S. L. 《Russian Journal of Applied Chemistry》2009,82(9):1675-1681
A series of complexes of chitosans of various molecular weights (3000–150000) with copper, iron(II), and zinc sulfates were
examined. Participation of amino groups of the polymer in coordination bonding with the metal was proved by IR spectroscopy.
The affinity of chitosan for iron ions was enhanced by introducing phenolic fragments into the polymer. 相似文献
19.
《Journal of Coordination Chemistry》2012,65(6):621-627
Cephradine (Hcephra) interacts with transition metal ions to give [Fe(cephra)Cl2] and [M(cephra)Cl] complexes (M?=?Mn(II), Co(II), Ni(II), Cu(II) and Zn(II)) which were characterized by physicochemical and spectroscopic methods; a tetrahedral geometry is suggested for their structures where cephradine behaves as monoanionic tridentate ligand. The complexes have been screened for antibacterial activity against several bacteria, and the results showed that all metal complexes tested had lower antibiotic activity than the free ligand. 相似文献
20.
Cefoxitin (Hcefoxi) interacts with transition metal ions to give [M(cefoxi)Cl] complexes [M=Fe(III), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II)] which were characterized by physicochemical and spectroscopic methods. A tetrahedral geometry is suggested for their structure, where the cefoxitin behaves as a monoanionic tridentate ligand. The complexes have been screened for antibacterial activity against several bacteria, and the results show that they are less active than the parent cefoxitin. 相似文献