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1.
The [((C6H5)3P)2N]+, [(C6H5)4P]+ and [N(CH3)4]+ salts of SeF5, SeF62− and SeOF3 and CsSeO2F were prepared and characterized. Crystal structures were obtained for [((C6H5)3P)2N][SeF5] and [((C6H5)3P)2N][SeOF3] CH2Cl2. In contrast to oxygen-bridged dimeric TeOF3, the SeOF3 anion in [((C6H5)3P)2N][SeOF3] CH2Cl2 is monomeric and represents the first experimentally well determined molecular structure of a monomeric trifluoro-chalcogenite anion. Similarly, [((C6H5)3P)2N][SeF5] represents the first example of a structure containing a well-isolated undistorted SeF5 anion. The NMR and the vibrational spectra and their assignments were re-examined and corrected by comparison with high-level theoretical calculations. Whereas the previously published normal coordinate analysis of SeF5 is correct, that for SeOF3 needs major revision.  相似文献   

2.
The magnetic behaviour of the compounds containing the [Ru2(DPhF)3(O2CMe)]+ ion (DPhF?=N,N′‐diphenylformamidinate) shows a strong dependence on the nature of the ligand bonded to the axial position. The new complexes [Ru2(DPhF)3(O2CMe)(OPMe3)][BF4]?0.5 CH2Cl2 ( 1 ? 0.5 CH2Cl2) and [Ru2(DPhF)3(O2CMe)(4‐pic)][BF4] ( 2 ) (4‐pic=4‐methylpyridine) clearly display this influence. Complex 1 ?0.5 CH2Cl2 shows a magnetic moment corresponding to a S=3/2 system affected by the common zero‐field splitting (ZFS) and a weak antiferromagnetic interaction, whereas complex 2 displays an intermediate behaviour between S=3/2 and S=1/2 systems. The experimental data of complex 1 are fitted with a model that considers the ZFS effect using the Hamiltonian ?D= S ? D ? S . The weak antiferromagnetic coupling is introduced as a perturbation, using the molecular field approximation. DFT calculations demonstrate that, in the [Ru2(O2CMe)(DPhF)3(L)]+ complexes, the energy level of the metal–metal molecular orbitals is strongly dependent on the nature of the axial ligand (L). This study reveals that the increase in the π‐acceptor character of L leads to a greater split between the π* and δ* HOMO orbitals. The influence of the axial ligand in the relative energy between the doublet and quartet states in this type of complexes was also analysed. This study was performed on the new complexes 1 ?0.5 CH2Cl2 and 2 . The previously isolated [Ru2(DPhF)3(O2CMe)(OH2)][BF4]?0.5 CH2Cl2 ( 3 ? 0.5 CH2Cl2) and [Ru2(DPhF)3(O2CMe)(CO)][BF4]?CH2Cl2 ( 4 ?CH2Cl2) complexes were also included in this study as representative examples of spin‐admixed and low‐spin configurations, respectively. The [Ru2(DPhF)3(O2CMe)]+ ( 5 ) unit was used as a reference compound. These theoretical studies are in accordance with the different magnetic behaviour experimentally observed.  相似文献   

3.
The reaction between tridentate NNO donor hydrazone ligands, (E)-2-cyano-N′-(phenyl(pyridin-2-yl)methylene)acetohydrazide (HL1) and (E)-2-cyano-N′-(1-(pyridin-2-yl)ethylidene)acetohydrazide (HL2), with MnCl2·4H2O in methanol resulted in [Mn(HL1)Cl2(CH3OH)] (1) and [Mn(HL2)Cl2(CH3OH)] (2). Molecular structures of the complexes were determined by single-crystal X-ray diffraction. All of the investigated compounds were further characterized by elemental analysis, FT-IR, TGA, and UV–Vis spectroscopy. These complexes were used as catalysts for olefin oxidation in the presence of tert-butylhydroperoxide (TBHP) as an oxidant. Under similar experimental conditions with equal manganese loading, the presence of [Mn(HL2)Cl2(CH3OH)] (2) resulted in higher conversion than [Mn(HL1)Cl2(CH3OH)] (1).  相似文献   

4.
Abstract

Four different series of N,N-dimethylaminoalkylchalcogenolates, viz. Me2NCH2 CH2E?, Me2NCH(Me)CH2E?, Me2NCH2CH(Me)E?, and Me2NCH2CH2CH2E? (E = S, Se, Te), (referred as EN) have been synthesized and characterized. Their reactions with palladium(II) and platinum(II) precursors have been explored. Complexes of the general formula, [MCl(EN)]n, [MCl(EN)2]n, [MCl(EN)(PR3)], [M2Cl2(μ-EN)2(PR3)2], [M2(μ-EN)2(PP)2]2+, etc. have been isolated. All the complexes have been characterized by elemental analysis, IR, NMR (1H, 13C, 31P, 77Se, 125Te, 195Pt), UV-vis, and FAB mass spectral data. A weak absorption in the electronic spectra of [MCl(EN)(PR3)] has been attributed to metal mediated ligand-to-ligand charge transfer and showed pronounced chalcogen dependence being red shifted on moving from S → Se → Te. Structures of several complexes have been established by X-ray diffraction analyses. Thermal behavior of some of these complexes has been investigated by TGA.  相似文献   

5.
The extraction of various metal ions from hydrochloric acid solutions with tris(2,6-dimethoxyphenyl)phosphine, [2,6-(MeO)2C6H3]3P, abbreviated to (2,6-MeOPh)3P, and its tertiary and quaternary phosphonium salts were studied. A series of phosphonium salts, [(2,6-MeOPh)3PH]+ClO?4, [(2,6-MeOPh)3PR]+Br? and {[(2,6-MeOPh)3P]2R′}2+ (Br?)2, where R = C12H25, C18H37 or C6H5CH2 and R′ = p-CH2C6H4CH2, (CH2)3 and (CH2)10, were synthesized and applied to an anion exchanger for chloro complex anions of various metal ions. (2,6-MeOPh)3P and [(2,6-MeOPh)3PR]+Br? were found to be effective for the extraction of metal ions such as iron(III), gold(III) and gallium(III), forming tetrachloro complex anions of the MIIICl?4 type. The extractabilities of the doubly charged cationic quaternary phosphonium salts [{(2,6-MeOPh)3P}2R′]2+ (Br?2, were found to be superior to those of the singly charged cationic phosphonium salts for metal ions such as cadmium(II), platinum(II) and palladium(II), forming a tetrachloro complex doubly charged aion of the MIICl2?4 type. Most of the metal ions are extracted through ion-pair formation between their chloro complex anions and the phosphonium cations.  相似文献   

6.
Two new Ni(II) complexes of 2,6-bis[1-(2,6-diethylphenylimino)ethyl]pyridine (L1), 2,6-bis[1-(4-methylphenylimino)ethyl]pyridine (L2 ) have been synthesized and structurally characterized. Complex Ni(L1)Cl2?·?CH3CN (1), exhibits a distorted trigonal bipyramidal geometry, whereas complex Ni(L1)(CH3CN)Cl2 (2), is six-coordinate with a geometry that can best be described as distorted octahedral. The catalytic activities of complexes 1, 2, Ni{2,6-bis[1-(2,6-diisopropyl-phenylimino)ethyl]pyridine} Cl2?·?CH3CN (3), and Ni{2,6-bis[1-(2,6-dimethylphenylimino) ethyl]pyridine}Cl2?·?CH3CN (4), for ethylene polymerization were studied under activation with MAO.  相似文献   

7.
Reaction of tris(2-hydroxyethyl)amine hydrochloride Cl N+H(CH2CH2OH)3 with zinc diacetate and bis(2-methylphenoxy)acetate in the molar ratio 2: 1 results in complexes 2[Cl N+H(CH2CH2OH)3]· Zn (OCOR)2 (I, II) R= Me (I), 2-MeC6H4OCH2 (II), which contain two protatrane cations linked with zinc diacylate by two coordination bonds HO → Zn. Complexes I and II are also formed by the reaction of the corresponding tris(2-hydroxyethyl)amine hydrochloride acylate RCOON+H(CH2CH2OH)3 with ZnCl2. The structure of complexes I, II is proved by elemental analysis, IR and 1H, 13C, 15N NMR spectroscopy.  相似文献   

8.
The complex formation of PdII with tris[2-(dimethylamino)ethyl]amine (N(CH2CH2N(CH3)2)3, Me6tren) was investigated at 25° and ionic strength I = 1, using UV/VIS, potentiometric, and NMR measurements. Chloride, bromide, and thiocyanate were used as auxiliary ligands. The stability constant of [Pd(Me6tren)]2+ in various ionic media was obtained: log β([Pd(Me6tren)] = 30.5 (I = 1(NaCl)) and 30.8 (I = 1(NaBr)), as well as the formation constants of the mixed complexes [Pd(HMe6tren)X]2+ from [Pd(HMe6tren)(H2O)]3+:log K = 3.50 = Cl?) and 3.64 (X? = Br?) and [Pd(Me6tren)X]+ from [Pd(Me6tren)(H2O)]2+: log K = 2.6 (X? = Cl?), 2.8(Br?) and 5.57 (SCN?) at I = 1 (NaClO3). The above data, as well as the NMR measurements do not provide any evidence for the penta-coordination of PdII, proposed in some papers.  相似文献   

9.
A very recent laser ablation‐molecular beam experiment shows that an Al+ ion can react with a single methylamine (MA, CH3NH2) or dimethylamine (DMA, (CH3)2NH) molecule to form a 1:1 ion–molecule complex Al+[CH3NH2] or Al+[(CH3)2NH)], whereas a dehydrogenated complex ion Cu+[CH3N] or Cu+[C2H5N] is detected, respectively, in the similar reaction for a Cu+ ion. Here, we show a comparative density functional theory study for the reactivities of the Al+ and Cu+ ions toward MA and DMA to reveal the intrinsic mechanism. It is found that the interactions of the Al+ ion with MA and DMA are mostly electrostatic, leading to the direct ion–molecule complexes, Al+? NH2CH3 and Al+? NH( CH3)2, in contrast to the non‐negligible covalent character in the corresponding Cu+‐containing complexes, Cu+? NH2CH3 and Cu+? NH( CH3)2. The general dehydrogenation mechanism for MA and DMA promoted by the Cu+ ion has been shown, and the preponderant structures contributing to the mass spectra of the product ions Cu+[CH3N] and Cu+[C2H5N] are rationalized as Cu+? NHCH2 and Cu+? N( CH2)( CH3). The presumed dehydrogenation reactions are also discussed for the Al+‐containing systems. However, the involved barriers are found to be too high to be overcome at low energy conditions. These results have rationalized all the experimental observations well. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010  相似文献   

10.
Dissociation processes of the organoaluminum compounds Al2(CH3)6 and Al2(CH3)3Cl3 have been studied in the range of valence and Al:2p core-level ionization by means of photoelectron–photoion and photoion–photoion coincidence techniques. The double-ionization threshold and the Al:2p core-ionization threshold of Al2(CH3)6 are estimated to be about 30 and 80 eV
  • 1 1 eV = 96.4853 kJ mol?1.
  • respectively. The relative yields of the H+?Al+ and H+?CHm,+ (m′ = 0–3) ion pairs are enhanced around the Al:2p core-ionization threshold of Al2(CH3)6. The photoion–photoion coincidence intensities of Al2(CH3)3Cl3 are negligibly small throughout the energy range studied. The ratio of the relative yield of AlC2H6+ to that of Al+ increases smoothly through the Al:2p core-ionization and/or excitation region of Al2(CH3)3Cl3. The variation of the fragmentation pattern with photon energy is discussed in conjunction with the relevant electronic states.  相似文献   

    11.
    The reactions of pyrimidine‐phosphine ligand N‐[(diphenylphosphino)methyl]‐2‐pyrimidinamine ( L ) with various metal salts of PtII, PdII and CuI provide three new halide metal complexes, Pt2Cl4(μ‐L)2·2CH2Cl2 ( 1 ), Pd2Cl4(μ‐L)2 ( 2 ), and [Cu2(μ‐I)2L2]n ( 3 ). Single crystal X‐ray diffraction studies show that complexes 1 and 2 display a similar bimetallic twelve‐membered ring structure, while complex 3 consists of one‐dimensional polymeric chains, which are further connected into a 2‐D supramolecular framework through hydrogen bonds. In the binuclear complexes 1 and 2 , the ligand L serves as a bridge with the N and P as coordination atoms, but in the polymeric complex 3 , both bridging and chelating modes are adopted by the ligand. The spectroscopic properties of complexes 1 ‐ 3 as well as L have been investigated, in which complex 3 exhibits intense photoluminescence originating from intraligand charge transfer (ILCT) π→π* and metal‐to‐ligand charge‐transfer (MLCT) excited states both in acetonitrile solution and solid state, respectively.  相似文献   

    12.
    Mixed sulfur donor ligand complexes of the type bismuth(III) bis(N,N‐dialkyldithiocarbamato) alkylenedithiophosphate, [R2NCS2]2BiS2POGO [where R = CH3 and C2H5; G = ‐CH2‐C(C2H5)2‐CH2‐, ‐CH2‐C(CH3)2‐CH2‐, ‐CH(CH3)‐CH(CH3)‐ and ‐C(CH3)2‐C(CH3)2‐] were synthesized in 1:1 molar ratio of bismuth(III) bis(N,N‐dialkyldithiocarbamate) chloride and ammonium alkylenedithiophosphate in refluxing benzene and characterized by melting point, molecular weight determinations, elemental analysis (C, H, N, Bi and S) and spectral [UV, IR,NMR (1H,13C and 31P) and powder X ray diffraction] studies; all these studies were in good agreement with the synthesized complexes. These newly synthesized derivatives are yellow and brown colored solids and are soluble in common organic solvents like benzene, chloroform, dichloromethane and DMF. Based on the physicochemical and spectral studies, a tentative structure of these newly synthesized complexes was assigned and the average particle size of the synthesized complexes determined by powder XRD, showing that nano range polycrystalline particles were formed with a monoclinic crystal system. These complexes were also screened for their antimicrobial activities using the well diffusion method. The free ligands as well as their mixed metal complexes were tested in vitro against four bacterial strains: two Gram‐positive, Staphylococcus aureus (ATCC 9144) (G+) and Bacillus subtilis (ATCC 6051), (G+) and two Gram‐negative, Escherichia coli (ATCC 9637) (G?) and Pseudomonas aeruginosa (ATCC 25619) (G?) to assess their antimicrobial properties. The results were indeed positive and exhibited good antibacterial effects. Chloroamphenicol used as a standard for comparison and synthesized complexes showed good antibacterial effects over chloroamphenicol. On the basis of these studies, the synthesized complexes help to understand the different structural and biological properties of main group elements with sulfur donor ligands. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

    13.
    Force Constants of Compounds of the Type (CH3)3ElCl+X?(El = N, P, As, Sb; X? = SbCl6?) For the cations (CH3)3NCl+ ( 1 ), (CH3)3PCl+ ( 2 ), (CH3)3AsCl+ ( 3 ), and (CH3)3SbCl+ ( 4 ) a normal coordinate analysis using a general valence force field is performed by the method of Fadini. The force constants are discussed. Calculations of the potential energy distribution show, that the skeletal vibrations in 4 are all characteristic vibrations, but there is a strong coupling of vibrations in 1 .  相似文献   

    14.
    Preparation of Trifluormethylhalogen Iodate(I) Salts (CH3)4N+CF3IX? (X = F, Cl, Br) and Trifluormethyltrifluormethoxy Iodate(I) (CH3)4N+CF3IOCF3? We describe the preparation of new trifluormethyliodate(I) salts CF3IX? (X = F, Cl, Br, OCF3). (CH3)4N+CF3ICl? and (CH3)4N+CF3IBr? are obtained via addition of CF3I with the corresponded tetramethylammonium halogenide. (CH3)4N+CF3IOCF3? is synthesized by comproportionation of (CH3)4N+CF3ICl? with CF3OCl under formation of Cl2 at ?78°C. (CH3)4N+CF3IF? is formed either, through thermolysis of (CH3)4N+ CF3IOCF3? under separation of COF2, or reaction of CF3I with (CH3)4N+ OCF3?. The thermolabile compounds have been characterized by i.r., Raman, 19F-, 13C NMR spectroscopy.  相似文献   

    15.
    Two [N???I+???N] halogen‐bonded dimeric capsules using tetrakis(3‐pyridyl)ethylene cavitands with different lower rim alkyl chains are synthesized and analyzed in solution and the gas phase. These first examples of symmetrical dimeric capsules making use of the iodonium ion (I+) as the main connecting module are characterized by 1H NMR spectroscopy, diffusion ordered NMR spectroscopy (DOSY), electrospray ionization mass spectrometry (ESI‐MS), and ion mobility‐mass spectrometry (TW‐IMS) experiments. The synthesis and effective halogen‐bonded dimerization proceeds through analogous dimeric capsules with [N???Ag+???N] binding motifs as the intermediates as evidenced by the X‐ray structures of (CH2Cl2)2@[ 3 a 2?Ag4?(H2O)2?OTs4] and (CH2Cl2)2@[ 3 a 2?Ag4?(H2O)4?OTs4], two structurally different capsules.  相似文献   

    16.
    The kinetics and mechanism of the uncatalyzed and Ru(III)‐catalyzed oxidation of methylene violet (3‐amino‐7‐diethylamino‐5‐phenyl phenazinium chloride) (MV+) by acidic chlorite is reported. With excess concentrations of other reactants, both uncatalyzed and catalyzed reactions had pseudo‐first‐order kinetics with respect to MV+. The uncatalyzed reaction had first‐order dependence on chlorite and H+ concentrations, but the catalyzed reaction had first‐order dependence on both chlorite and catalyst, and a fractional order with respect to [H+]. The rate coefficient of the uncatalyzed reaction is (5.72 ± 0.19) M?2 s?1, while the catalytic constant for the catalyzed reaction is (22.4 ± 0.3) × 103 M?1 s?1. The basic stoichiometric equation is as follows: 2MV+ + 7ClO2? + 2H+ = 2P + CH3COOH + 4ClO2 + 3Cl?, where P+ = 3‐amino‐7‐ethylamino‐5‐phenyl phenazinium‐10‐N‐oxide. Stoichiometry is dependent on the initial concentration of chlorite present. Consistent with the experimental results, pertinent mechanisms are proposed. The proposed 15‐step mechanism is simulated using literature; experimental and estimated rate coefficients and the simulated plots agreed well with the experimental curves. © 2003 Wiley Periodicals, Inc. Int J Chem Kinet 35: 294–303, 2003  相似文献   

    17.
    Bis(N, N′‐dialkyldithiocarbamato)antimony(III) alkylenedithiophosphates of the type [R2NCS2]2 SbS(S)POGO [where NR2 = N(CH3)2, N(C2H5)2 and N(CH2)4; G = ? CH2? C(C2H5)2? CH2? , ? CH2? C(CH3)2? CH2? , ? CH(CH3)? CH(CH3)? and ? C(CH3)2? C(CH3)2? ] were synthesized and characterized by physico‐chemical, spectral [UV, IR and NMR (1H, 13C and 31P)] and thermal (TG, DTA and DSC) analysis. The TG decomposition analysis step of the complex indicated the formation of Sb2S3 as the final product. The first endothermic peak in DSC indicated the melting point of the complexes. These complexes were screened for their antimicrobial activities using the disk diffusion method. All the complexes showed good activity as antibacterial and antifungal agents on some selected bacterial and fungal strains, which increased on increasing the concentration. Chloroamphenicol and terbinafin were used as standards for comparison. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

    18.
    Metal Complexes of Biologically Important Ligands. CXXVI. Palladium(II) and Platinum(II) Complexes with the Antimalarial Drug Mefloquine as Ligand The coordination sites of the antimalarial drug mefloquine (L) were studied. Reactions of the chloro bridged complexes (allyl)Pd(μ‐Cl)2Pd(allyl) and (R3P)(Cl)M(μ‐Cl)2M(Cl)(PR3) (M = Pd, Pt) with racemic mefloquine give the compounds (allyl)(Cl)Pd(L) ( 1 ), Cl2(Et3P)Pt(L) ( 2 ) and Cl2(Et3P)Pd(L) ( 3 ) with coordination of the piperidine N atom of mefloquine. In the presence of NaOMe the N,O‐chelate complexes Cl(Et3P)Pt(L–H+) ( 4 ) and Cl(R3P)Pd(L–H+) ( 5 , 6 , R = Et, nBu) were obtained. Protection of the piperidine N atom of mefloquine by protonation allows the synthesis of the complexes Cl2(Et3P)Pt(L + H+) ( 7 ) in which mefloquine is coordinated via the quinoline N atom. The structures of 2 , 3 and 4 were determined by X‐ray diffraction analysis. In the crystal of 4 pairs of enantiomers are found which are linked by two hydrogen bridges between the amine group and the chloro ligand.  相似文献   

    19.
    Synthesis and Properties of Diphthalocyaninates of Bismuth, [Bi(Pc)2]k (k = 1?, 0, 1+); Crystal Structure of mixed-valent [Bi(Pc)2] · CH2Cl2 Blue di(phthalocyaninato(2-))bismuthate(III), [Bi(Pc2?)2]?, is obtained by the reaction of BiO(NO3) with molten 1,2-dicyanobenzene in the presence of potassium methylate and isolated as tetra-n-butylammonium (nBu4N)+ and bis(triphenylphosphine)iminium (PNP)+ salt. Green mixed-valent [Bi(Pc)2] · CH2Cl2 is prepared by anodic oxidation of [Bi(Pc2?)2]?. It crystallizes in the orthorhombic γ modification (Pnma; a = 28.176(5), b = 22.913(3), c = 7.925(1) Å, Z = 4). The BiIII ion is eightfold coordinated by the Niso atoms of the slightly distorted Pc ligands in a square antiprismatic manner. The average Bi? Niso bond distance is 2.467 Å. The complex is paramagnetic (μeff = 1.84 μB). Oxidation of [Bi(Pc2?)2]? with bromine yields purple, diamagnetic [Bi(Pc?)2]Brx (1.5 ≤ x ≤ 2.5). The redox properties are investigated electrochemically. UV-Vis-NIR, MIR/FIR and resonance Raman spectra of the new bismuth(III) complexes are discussed and compared with those of diphthalocyaninates of the lanthanides.  相似文献   

    20.
    Phosphorane Iminato Complexes of Antimony. The Crystal Structures of [Sb2Cl5(NPMe3)2][SbCl6] · CH3CN and [SbCl(NPPh3)]2[SbCl6]2 · 6 CH3CN The title compounds are formed by reaction of antimony pentachloride in acetonitrile solution with the phosphorane iminato complexes SbCl2(NPMe3) and SbCl2(NPPh3), respectively, which themselves are synthesized by reaction of antimony trichloride with Me3SiNPR3 (R = Me, Ph). The complexionic compounds are characterized by 121Sb Mössbauer spectroscopy and by crystal structure determinations. [Sb2Cl5(NPMe3)2][SbCl6] · CH3CN: Space group P41, Z = 4, 3 698 observed unique reflections, R = 0.022. Lattice dimensions at ?60°C: a = b = 1 056.0(1), c = 2 709.6(2) pm. The structure consists of SbCl6? ions and cations [Sb2Cl5(NPMe3)2(CH3CN)]+, in which one SbIII atom and one SbV atom are bridged by the N atoms of the phosphorane iminato ligands. [SbCl(NPPh3)]2[SbCl6]2 · 6 CH3CN: Space group P1 , Z = 2, 5 958 observed unique reflections, R = 0.033. Lattice dimensions at ?60°C: a = 989.4(11), b = 1 273(1), c = 1 396(1) pm, α = 78.33(7), β = 77.27(8)°, γ = 86.62(8)°. The structure consists of SbCl6? ions and centrosymmetric cations [SbCl(NPPh3)(CH3CN)2]22+, in which the antimony atoms are bridged by the N atoms of the phosphorane iminato ligands.  相似文献   

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