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1.  An x-ray structure analysis has revealed substantial diferrences in the conformational states of 2,3-(4-benzoyl)benzo-15-crown-5 and benzo-15-crown-5 in the crystal phase, differences related to realization of a trans-gauche-gauche' conformation in one COCCOC fragment in the 2,3-(4-benzoyl)benzo-15-crown-5.
2.  In nonpolar solvents, an equilibrium of several structures is realized in both compounds, an equilibrium with the participations of trans-gauche-trans, trans-gauche-gauche and trans-gauche-gauche' conformations. In a polar medium, there are no indications of the trans-gauch-gauche' conformation.
3.  Upon complexation of the ligands with calcium thiocyanate in acetonitrile, there are spectral indications of complexes with differing stoichiometry, with a large contribution of the structure from trans-gauche-trans conformations.
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 833–838, April, 1989.  相似文献   

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Summary Cobalt(II), nickel(II), palladium(II) and platinum(II) complexes witho-(OCD),m-(MCD) andp-chlorophenyldithiocarbamate (PCD) ligands have been synthesised and characterised by chemical analyses, molecular weight determinations, conductance measurements, electronic and i.r. spectral studies. The thermal behaviour of the complexes has been studied by t.g. and d.t.a. techniques in a static air atmosphere and heats of reaction of different decomposition steps have been calculated from the d.t.a. curves. The thermal decomposition products of the complexes were identified by elemental analyses and i.r. spectra.  相似文献   

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Several monomethinecyanine, merocyanine and styryl dyes were synthesized using a 5,6-(1,4,7,10,13-pentaoxacyclotridecane)-benzothiazole derivative as the starging reageni. A study was made of their spectral characteristics and the effect which complexing with alkaline and alkaline-earth metal salts had on their chromaticity.Organic Chemistry Institute, National Academy of Sciences of Ukraine, Kiev. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 992–996. Original article submitted March 12, 1996.  相似文献   

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The preparation and X-ray crystal structures of the adducts of 10-thiabenzo-15-crown-5 and 10-selenabenzo-15-crown-5 with PdCl2 are reported. [PdCl2(C14H20O4S)2] (1): or-thorhombic, space group Pbca with cell dimensions of a=17.285(5), 6=8.354(3), c=21.689(4) A, K=3131.9 A3, Z=4;R=0.0330 for 2301 reflections with I > 3o(I), [PdCl2(C14H2oO4Se)2] (2): monoclinic, space group P21/n with cell dimensions of a=18.928(4), b=8.912(3), c=9.813(2) A, β=96.90(2)0, V=1643.4 A3, Z=2; R=0.0289 for 2617 reflections with I> 3σ(I), Both complexes are monomeric, square-planar palladiurn(Ⅱ) compounds with the Pd(Ⅱ) ion situating on a crystal-lographic inversion centre, and the crown ligands all adopt the axial coordination with the Pd-S bond of 2.3233(7) A and the Pd-Se bond of 2.4357(3) A. Their complexing characteristics are discussed in brief.  相似文献   

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Summary TheN-aminorhodanine (L) complexes: PdLX, (X = Br or I), ML1.5Cl2 (M = Pd or Pt), PtL2X2 (X = Br, I or ClO4), PdL3(ClO4)2, PdL1.5Cl4 and PdL3(ClO4)4 have been prepared and investigated. The ligand is bonded to the metal ion through the aminic nitrogen atom as monodentate or through this atom and the thiocarbonylic sulphur atom when it acts as chelating or bridging ligand. The carbonylic oxygen atom is never coordinated.  相似文献   

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New benzo-15-crown-5 derivatives containing nitro, amine and imine groups were prepared. Nitro compound (1) was prepared after the reaction?4′,5′-bis(bromethyl)benzo-15-crown-5 and o-nitrophenol in the presence of NaOH. After reduction process by using hydrazine hydrate and Pd/C amine compound (2) was formed. New crown ether imine compounds (35) were synthesized by the condensation of corresponding crown ether diamine (2) with salicylaldehyde derivatives. Sodium complexes of the crown compounds (1a5a) form crystalline 1:1 (Na+: ligand) complexes with sodium perchlorate. Nickel(II) complexes (3b5b) with 1:1 (Ni2+:ligand) stoichiometries were also been synthesized from the Schiff bases (35). The results indicated that the Schiff base ligands coordinated through the azomethine nitrogen and phenolic oxygen. The extraction ability of compounds (1, 3, 4 and 5) were also evaluated in chloroform by using several alkali and transition metal picrates such as Li+, Na+, K+, Cr3+, Mn2+, Ni2+, Cu2+, Zn2+ and Pb2+.  相似文献   

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The reactions between four very simply substituted phospholes and the chlorides of Ni(II), Pd(II) and Pt(II) are described. The phospholes 1-phenylphosphole, 3-methyl-1-phenyl-phosphole and 3,4dimethyl-1-phenylphosphole all readily form bis-complexes of formula L2MCl2 [L = phosphole ligand and M = Ni(II), Pd(II) or Pt(II)] or tris-complexes of formula L3MCI2. 1-n-Butyl-3,4-dimethylphosphole appears to form stable complexes only with Ni(II). Evidence is put forward which indicates that the L2MCl2 complexes exist in a four-coordinate, square-planar monomeric/five coordinate equilibrium while the L3MCl2 complexes are primarily the ionic species [L3MCl]+ Cl? in solution. Comparisons are made with the behaviour of other simple phospholes which do not form Ni(II) complexes and the results are discussed briefly in terms of both aromatic and non-aromatic phosphole models.  相似文献   

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A new, potentially polydentate sulfur–nitrogen chelating agent, 2,6–bis(N-methyl-S-methyldithiocarbazato)pyridine (L) has been synthesized and characterized. With nickel(II) salts, the ligand yields complexes of empirical formula NiLX2·nH2O (X=Cl−, NCS− or NO3−; n=0 or 1) in which it behaves as a quadridentate NSSN chelating agent, coordinating to the nickel(II) ion via the two amino nitrogen atoms and the two sulfur atoms. Magnetic and spectral evidence support a distorted octahedral structure for these complexes. The ligand reacts with copper(II), platinum(II) and palladium(II) salts to yield homo-binuclear complexes of general formula [M2LX4]·nSol (M=CuII, PtII or PdII; X=Cl− or Br−; n=0.5, 1 or 2; Sol=H2O, MeOH or MeCOMe), in which each of the metal ions is in a square-planar environment. These complexes have been characterized by a variety of physicochemical techniques. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

11.
Summary Complexes of formulae Ni(HRS)2X2 (X=Cl or Br), M(HRS)2Y2 (M=Ni or Pd; Y=NO2 or C1O4), Pd(HRS)X2 (X=Cl, Br or I), Pt(HRS)X2 (X=Cl or Br), Pt(HRS)2(ClO4)2 and M(RS)2 (M=Pd or Pt) where HRS and RS denote 1-methyl-4-mercaptopiperidine in the zwitterionic or in the thiolato form, respectively, have been prepared and characterized. In all the complexes the ligands are coordinated exclusively through sulphur. Polymeric structures consisting of square-planar geometry with sulphur-bridged metal atoms are proposed in each case.  相似文献   

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苯并-15-冠-5-四溴合铟(III)酸钾,KInBr~4(C~14H~20O~5)~2,晶体属单斜晶系,空间群为C~2h^5-P2~1/n,晶胞参数a=14.402(3),b=15.082(3),c=17.262(5)A,β=93.42(2),Z=4.非氢原子的位置由Patterson函数及Fourier合成法找出,经全矩阵最小二乘法修正R=0.057.结构分析表明K^+和两个苯并-15-冠-5(B-15-C-5)分子直接配位,对阴离子为InBr~4^-,具有四面体构型.InBr~4^-与配阳离子K(B-15-C-5)~2^+依靠静电引力结合为离子对.由此说明,In(III)在过量KBr存在下可以被B-15-C-5定量地萃取至有机相中.  相似文献   

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The oxygenation constants(Ko_2)of cobalt(Ⅱ)hydroxamates(CoL_2~1-CoL_2~3)with benzo-15-crown-5(B15C5)pendants were measured over the range of-5 to 20℃,and the values of thermodynamic parameters(ΔH~0 andΔS~0)were calculated based on these(No_2)values.Meanwhile,these crowned complexes were employed to the oxidation for p-xylene to p-toluic acid with air at 110Δunder normal atmospheric pressure.The effects of B15C5 pendant and the length of chain bonded to B15C5 in these complexes on the O_2-binding capabilities and oxidation for p-xylene were investigated with the comparison of crown-free analogues CoL_2~4.  相似文献   

14.
A series of palladium(II) complexes with 1,2-bis[di(benzo-15-crown-5)phosphino]ethane ligand (dbcpe), [Pd(dbcpe)X2] (X = Cl 1, Br 2 and I 3), have been successfully synthesised and characterised. The X-ray crystal structure of dbcpe has also been determined. The cation-binding properties of the complexes have been studied and the stability constants with alkali metal cations determined. The crown-free analogue of dbcpe, 1,2-bis[bis(3,4-dimethoxyphenyl)phosphino]ethane (ddmppe), and the related complexes have also been prepared and comparison studies have been made.  相似文献   

15.
The effects of four d8 transition-metal complexes from Group 10 on the thermal, mechanical, optical, and spectroscopic properties of atactic 1,2-polybutadiene are compared, in addition to their ability to induce gelation. Olefin coordination and subsequent metal-catalyzed chemical crosslinking occur much more quickly, and to a greater extent, at ambient temperature with PdCl2(CH3CN)2 than with PtCl2(C6H5CN)2. Alkene side groups in the polymer attack the pseudo-square-planar metal center (i.e., Pd2+ or Pt2+) from above or below the plane of the coordinatively unsaturated low-molecular-weight organometallic complex and displace neutral acetonitrile or benzonitrile ligands via an associative mechanism. Gelation occurs much more quickly with Pd2+ than with Pt2+, and the ambient-temperature elastic modulus of solid polybutadiene/palladium complexes increases significantly, without high-temperature annealing, so that a weak rubbery polymer is transformed into a glass via 3 mol % Pd2+. Alkene functional groups in the side chain of the polymer do not coordinate to bis(dimethyl)glyoximatonickel(II) at ambient temperature because (1) it is difficult to displace anionic dimethylgloxime ligands that are bidentate; (2) these planar nickel complexes with C2h symmetry are stacked along the c axis via interlocking methyl groups on adjacent molecules; and (3) there is a lack of π back-bonding between dxy on Ni(II) and empty π* antibonding orbitals of CC, which typically stabilizes olefin complexes with pseudo-square-planar d8 metal centers. Pseudo-octahedral nickel(II) chloride hexahydrate does not form a complex with the polymer, in agreement with some macroscopic properties of these materials. The observed trend in the transition-metal-modified properties of atactic 1,2-polybutadiene in the solid state and in the gel state is Pd(II) > Pt(II) ≫ Ni(II). © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 2270–2285, 2004  相似文献   

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周雅仙  张宪新 《化学学报》1988,46(5):496-499
本文用斜率法、饱和法以及通过与萃取合物相对应的冠醚配合物晶体的制备及其性质研究, 探讨了In^3^+的萃取机理, 测定并计算了表观萃取平衡常数, 将此萃取体系应用于铟和某些体系应用于铟和某些金属离子的萃取分离, 亦获得较好的结果.  相似文献   

17.
NMR, IR and MS were used for identification of major products of radiolysis of benzo-15-crown-5 in chloroform. The crown ether exhibits high affinity towards inorganic products of radiolysis of chloroform resulting in the formation of complexes.  相似文献   

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Russian Chemical Bulletin - The extraction of tetrafluoroboric acid from aqueous solutions to a solution of benzo-15-crown-5 (B15С5, 1 mol L-1) in chloroform is shown to occur due to...  相似文献   

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