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1.
The reaction of the dimer complex [{Ru(CO)3Cl2}2] with the ligands 4,6-dichloroquinoline-5,8-dione and 6-methoxybenzo[g]quinoline-5,10-dione in ethanol solution led to the neutral mononuclear complexes of general formula [Ru(CO)2Cl22-quinolinedione-N,O)]. The complexes were characterized by elemental analysis, IR and RMN spectroscopy, and the molecular structure of [Ru(CO)2Cl2(6-methoxybenzo[g]quinoline-5,10-dione)] was determined by single-crystal X-ray diffraction. The redox chemistry of ligands and complexes was investigated by cyclic voltammetry, and their potential antitumor activity was also evaluated.  相似文献   

2.
Soluble homogeneous organophosphorus—nickel complexes have been used to detoxify polychlorinated biphenyls (PCBs) by catalyzed hydrodechlorination using NaBH2(OCH2CH2OCH3)2 as the hydrogen source. The reactions appear to proceed by NiL3 oxidative addition into C---Cl bonds followed by hydrogenolysis of the metal---carbon bond. In model experiments with decachlorobiphenyl, the cone angle of the organophosphorus ligand L was shown to be a key factor controlling the magnitude and position of chlorine displacement. Hence, ligands leading to para displacement (e.g. (o-MeC6H4O)3P), meta—para displacement (e.g. (EtO)3P and (PhO)3P), and ortho—meta—para displacement (e.g. Me3P and Et3P) were found. Significantly, the highly toxic, coplanar dioxin precursor 3,3′,4,4′-tetrachlorobiphenyl, a meta—para chlorine-substituted congener, was dechlorinated quantitatively with the Et3P catalyst system. Evidence for the presence of organonickel intermediates in the reaction mixtures was obtained by mass spectroscopic and X-ray diffraction studies. Of particular interest is the isolation of square planar complexes p-C6Cl5C6Cl4Ni(PEt3)2Cl from the reaction of decachlorobiphenyl with NaBH2(OCH2CH2OCH3)2—(Et3P)2NiCl2 as the catalyst precursor and m-C6Cl5C6Cl4Ni(PEt3)2Cl from decachlorobiphenyl—Ni(1,5-C8H12)2—PEt3 at room temperature. All are oxidative addition intermediates and precursors for decachlorobiphenyl hydrodechlorination.  相似文献   

3.
Racemic [C5H5Mo(CO)2LL]PF6, (2) with LL = 2-benzoylpyridine-1-phenylethylimine, undergoes spontaneous resolution upon crystallization from acetone/CH2Cl2/ethanol. The absolute configuration of the (+)546-isomer was shown to be (R) at the Mo atom and (R) at the asymmetric carbon atom. Comparison of 2 with [C5H5Mo(CO)2LL]PF6 (1) (LL = 2-carbaldehydepyridine-1-phenylethylimine) reveals distinct changes caused by the differences resulting from the presence of the phenyl group in 2 and the change from the (RR)- to the (RS)-configuration.  相似文献   

4.
以二苯基-1-甲基咪唑膦(dpim)为配体制备了一种新型的配合物催化剂Ni(dpim)2Cl2. 循环伏安研究表明,Ni(dpim)2Cl2配合物在氮气气氛下表现出两步还原的电化学行为,在-0.7 V下为两电子的不可逆还原,在-1.3 V下为单电子准可逆还原. 向电解液中通入CO2后,在-1.3 V下的还原峰变得不可逆,且其峰电流从0.48 mA·cm-2增大到0.55 mA·cm-2. 在质子源(CH3OH)存在的条件下,该还原峰电流可继续增大到0.72 mA·cm-2. 该研究结果表明,Ni(dpim)2Cl2配合物对CO2还原具有良好的电催化性能,且其电催化还原过程符合ECE机理. 在-1.3 V下恒电位电解得到的还原产物主要为CO,催化转换频率(Turnover of Frenquency, TOF)为0.17 s-1.  相似文献   

5.
The reaction of Ru(CO)4(C2H4) or Ru(CO)5 with 1,5-Ph4P2N4S2 in CH2Cl2/hexane at 23°C produces the dimer [Ru(CO)2(Ph4 P2N4S2)]2 (2), which was shown by X-ray crystallography to have a centrosymmetric structure in which the P2N4S2 ring is attached to one ruthenium atom through two (geminal) nitrogen atoms and the remote sulfur atom and serves as a bridge to the other ruthenium atom via the second sulfur atom. Crystals of 2 ·2(CH2Cl2) are triclinic, space group P (No. 2), a = 12.901(1) Å, b = 13.072(1) Å, c = 10.123(1) Å, = 100.88(1)°, β = 98.90(1)°, γ = 67.50(1)°, V = 1542.4(3) Å, Z = 1 with final R and Rw values of 0.040 and 0.027, respectively.  相似文献   

6.
In toluene as medium, tetra(cyclopentadienyl)niobium(IV), NbCp4, has been prepared in satisfactory yields from the reaction of NaCp with: (a) Nb2C110, (b) NbCl4(THF)2, or (c) NbCp2Cl2. Tetracyclopentadienylniobium(IV) has been characterized by X-ray diffraction. Crystal data: C20H20Nb, M=353.29 g mol−1, hexagonal, space group P65 (no. 170), a=b=9.396(2), c=31.23(3) Å, V=2388(2) Å3, Z=6, dcalc=1.48 g cm−3, λ(Cu–K)=1.54184 Å, T=291 K, μ=62.04 cm−1, F(000)=1686. Two of the four cyclopentadienyl ligands are bonded to niobium in a pentahapto fashion, the other two being monohapto. NbCp4 undergoes cyclopentadiene elimination in the presence of species containing active protons such as Ph3SiOH or strong acids, the products being tris- or biscyclopentadienyl compounds depending on the molar ratio of the reagents.  相似文献   

7.
Sn(CH3)2Cl2 exerts its antitumor activity in a specific way. Unlike anticancer cis-Pt(NH3)2Cl2 drug which binds strongly to the nitrogen atoms of DNA bases, Sn(CH3)2Cl2 shows no major affinity towards base binding. Thus, the mechanism of action by which tinorganometallic compounds exert antitumor activity would be different from that of the cisplatin drug. The aim of this study was to examine the binding of Sn(CH3)2Cl2 with calf thymus DNA and yeast RNA in aqueous solutions at pH 7.1–6.6 with constant concentrations of DNA and RNA and various molar ratios of Sn(CH3)2Cl2/DNA (phosphate) and Sn(CH3)2Cl2/RNA of 1/40, 1/20, 1/10, 1/5. Fourier transform infrared (FTIR) and UV–visible difference spectroscopic methods were used to determine the Sn(CH3)2Cl2 binding mode, binding constant, sequence selectivity and structural variations of Sn(CH3)2Cl2/DNA and Sn(CH3)2Cl2/RNA complexes in aqueous solution. Sn(CH3)2Cl2 hydrolyzes in water to give Sn(CH3)2(OH)2 and [Sn(CH3)2(OH)(H2O)n]+ species. Spectroscopic evidence showed that interaction occurred mainly through (CH3)2Sn(IV) hydroxide and polynucleotide backbone phosphate group with overall binding constant of K(Sn(CH3)2Cl2–DNA)=1.47×105 M−1 and K(Sn(CH3)2Cl2–RNA)=7.33×105 M−1. Sn(CH3)2Cl2 induced no biopolymer conformational changes with DNA remaining in the B-family structure and RNA in A-conformation upon drug complexation.  相似文献   

8.
Two homoleptic Re(I) complexes of ortho and para-carborane isocyanide ligands were prepared as the first examples of a new class of metal-based BNCT and BNCS agents. The target compounds were prepared in low yield through the reaction of [Re2(O2CPh)4Cl2] and [Re2(OAc)4Cl2] with 3-isocyano-1,2-dicarba-closo-dodecaborane and a para-carborane azetidine derivative respectively. The desired product from the latter reaction was characterized crystallographically and is only the second reported molecular structure of a homoleptic Re(I) isonitrile complex.  相似文献   

9.
The synthesis and characterization of a number of new coordination compounds of PdII with the nitrogen donor 1-tert-butylpyrazole (tBuPzH) are described. Compounds are trans-[Pd(tBuPzH)2Cl2] and the cyclometallated structures [Pd2(tBuPz)2(AcO)2] and [Pd3(tBuPz)2(AcO)4]. All these complexes are mixtures of syn and anti isomers. Also, the chloro-bridged complex [Pd2(tBuPz)2Cl2] has been isolated as an equilibrium mixture of cis and trans isomers. The compounds have been studied by variable temperature 1H- and 13C-NMR spectroscopy.  相似文献   

10.
Reaction of phenyl magnesium bromide with the ,β-unsaturated ketone 3-methyl-2,3,4,5,6,7-hexahydroind-8(9)-en-1-one, followed by an aqueous work-up, generates the pro-chiral tetra-substituted cyclopentadiene, 1-phenyl-3-methyl-4,5,6,7-tetrahydroindene, CpH, a precursor to the η5-cyclopentadienyl ligand in (Cp)2Fe and [(Cp)Fe(CO)]2(μ-CO)2. Both complexes were generated as mixtures of rac-(RR and SS)- and meso-(RS)-isomers, and in either case pure meso-isomer was isolated by crystallisation and characterised by single crystal X-ray structure, both molecules having crystallographic Ci symmetry. Reduction with Na/Hg cleaves meso-(RS)-[(Cp)Fe(CO)]2(μ-CO)2 and the resulting mixture of (R)- and (S)-[(Cp)Fe(CO)2] anions reacts with MeI to give racemic (Cp)Fe(CO)2Me, which was characterised by the X-ray crystal structure. The Cp ligand is more electron donating than (η-C5H5) as revealed by the reduction potential of the (Cp)2Fe+/(Cp)2Fe couple, E°=−0.127 V (vs. Ag  AgCl). Reaction of LiCp with ZrCl4 yields the zirconocene dichloride [Zr(Cp)2Cl2] as mixture of rac- and meso-isomers, from which pure rac-isomer is obtained as a mixture of RR and SS crystals by recrystallisation. The reaction of rac-[Zr(Cp)2Cl2] with LiMe gives rac-[Zr(Cp)2Me2]. The structures of RR-[Zr(Cp)2Cl2] and rac-[Zr(Cp)2Me2] have been determined by X-ray diffraction. The structural studies reveal the influence of the bulky substituted cyclopentadienyl ligand on the metal---Cp distances and other metric parameters.  相似文献   

11.
The composition of (C6Me6)TiAl2Cl8−xEtx complexes in (C6Me6)TiAl2Cl8 + n Et3Al (n = 0.5-6) systems was studied by UV-Vis spectroscopy and the X-ray crystal structure of one of them, (η6-C6Me6)Ti[(μ-Cl)2(AlClEt)]2 (IIa-2), has been determined. The complex crystallizes in the orthorhombic space group Pna21 with Z = 4 and lattice parameters a 15.634(3), b 11.355(2), c 14.417(2) Å. The ethyl groups of IIa-2 reside in outer positions of aluminate ligands farther away from the C6Me6 ligand. The other part of the complex does not differ remarkably from structures of other (arene)TiII complexes. Negligible activity of (C6Me6)TiAl2Cl8 towards the butadiene cyclotrimerization is considerably increased by addition of 2.5–3.0 equivalents of Et3Al. As follows from UV-Vis spectra, such systems contain mainly the (C6Me6)TiAl2Cl5Et3 complex. It is suggested that the introduction of three Et substituents destabilizes the Ti-(η6-C6Me6) bond so that the replacement of hexamethylbenzene by butadiene in the first step of a catalytic cycle becomes more feasible.  相似文献   

12.
采用机械研磨的方法, 通过控制反应前驱体的摩尔比, 研究了不同球磨时间对形成RbPb2Cl5晶体的影响. X射线衍射结果表明, 经过1 h的研磨可制备纯相RbPb2Cl5晶体粉末, 其结构为通过边共享相连接的 [Pb-Cl7]十面体, 归属于单斜晶系P21/c空间点群. RbPb2Cl5晶体在紫外区有明显的吸收, 其带边吸收值为 3.82 eV. 在光激发条件下, 该晶体显示激发波长依赖的540 nm黄绿光和635 nm橙光的双波长荧光. 变温光谱、 时间分辨光谱和发射峰强度与能量密度依赖的线性关系研究表明, 其发光机制应该归结于材料具有两种不同的自陷激子态, 从而产生了与激发波长相关的双通道发射.  相似文献   

13.
[Mo2(OAc)4] reacts with three or more equivalents of lithium chloride and PMe3 in thf to give [Mo2Cl3(μ-OAc)(PMe3)3]0.75thf (1). The IR spectrum of the complex shows Mo---O and Mo---Cl stretches at 350 and 300 cm−1 respectively and the 1H and 13C NMR spectra suggest several species are present in solution. [Mo2Cl3(μ-OAc)(PMe3)3] converts slowly in thf to [Mo2Cl4(PMe3)4] and [Mo2(OAc)4]. The structure of [Mo2Cl3(μ-OAc) (PMe3)3]0.5C6H5Me (2) has been determined by single-crystal X-ray diffraction methods. Crystals of the toluene solvate are tetragonal with a = 20.726(2), c = 11.776(2) Å, space GROUP = I4cm. The structure was solved by Patterson and Fourier methods and refined to R of 0.035 for the 539 observed data. The molecule contains two metal centres each of which shows 5-fold coordination. The two molybdenum atoms are linked by an acetate bridge and a short Mo---Mo bond of 2.121(3) Å. Remaining coordination sites are occupied on Mo(1) by two Cl and one PMe3 and on Mo(2) by one Cl and two PMe3 groups.  相似文献   

14.
The first carbonyl molybdenum-(O) and -(II) complexes with phenylbis(2-pyridyl)phosphine (PPhpy2) have been synthesized. PPhpy2 reacts with [Mo(CO)5(NCMe)] to give [Mo(CO)5(PPhpy2-P)]. With [Mo(CO)4(NBD)] (NBD = norbornadiene) it gives [Mo(CO)4(PPhpy2-P)2] when a 2 : 1 ratio is used, or [MO(CO)4(py2PhP---N,N′)] for a 1 : 1 ratio. Decarbonylation of any of these pyridylphosphine complexes leads to an oligomer of formula {MO(CO)3(μ-PPhpy2)}n, which is also obtained after heating [MO(CO)6] in solution with an equimolar amount of PPhpy2. The oligomer undergoes oxidative addition by iodine or allylbromide to give [MoI2(CO)3(py2PhP---N,N′)], or [MoBr(η3-CH2CHCH2)(CO)2(py2PhP---N,N′)], respectively. These complexes are also obtained by addition of equimolar amounts of PPhpy2 to solutions of [MoI2(CO)3(NCMe)2] and MoBr(η3-CH2CH CH2)(CO)2(NCMe)2, respectively. The ligand tends to act as a P-donor towards molybdenum(O) substrates, and as a chelating N,N′-donor in molybdenum (II) complexes.  相似文献   

15.
采用自制的新型双苯并环己酮芳亚胺镍催化剂双苯并环己酮-2,6-二甲基苯亚胺镍(Ⅱ)(Ni{C10H8(O)C[2,6-C6H3(CH3)2N]CH3}2, C1)和双苯并环己酮-2,6-二氯苯亚胺镍(Ⅱ)(Ni{C10H8(O)C[2,6-C6H3Cl2N]CH3}2, C2)与三五氟苯硼[B(C6F5)3]结合, 在一定的反应条件下可高效催化降冰片烯(NB)与甲基丙烯酸正丁酯(n-BMA)的乙烯基加成共聚合. 提出了催化聚合时存在的可能失活机理; 研究了不同单体投料比对催化活性、 产率及产物性能的影响. 根据Kelen-Tüdõs方法分别估算出2种单体在不同催化体系下的竞聚率, 即当催化体系为C1/B(C6F5)3时, 竞聚率rn-BMA=0.02, rNB=16.28, rNB·rn-BMA=0.32; 当催化体系为C2/B(C6F5)3时, rn-BMA=0.01, rNB=64.83, rNB·rn-BMA=0.65. 结果表明, 2种单体在2种体系催化下均为无规共聚合.  相似文献   

16.
The neutral nitrogen-bidentate ligand, diphenylbis(3,5-dimethylpyrazol-1-yl)methane, Ph2CPz′2, can readily be obtained by the reaction of Ph2CCl2 with excess HPz′ in a mixed-solvent system of toluene and triethylamine. It reacts with [Mo(CO)6] in 1,2-dimethoxyethane to give the η2-arene complex, [Mo(Ph2CPz′2)(CO)3] (1). This η2-ligation appears to stabilize the coordination of Ph2CPz′ 2 in forming [Mo(Ph2CPz′2)(CO)2(N2C6H4NO2-p)][BPh4] (2) and [Mo(Ph2CPz′2)(CO)2(N2Ph)] [BF4] (3) from the reaction of 1 with the appropriate diazonium salt but the stabilization seems not strong enough when [Mo{P(OMe)3} 3(CO)3] is formed from the reaction of 1 with P(OMe)3. The solid-state structures of 1 and 3 have been determined by X-ray crystallography: 1-CH2Cl2, monoclinic, P21/n, a = 11.814(3), b = 11.7929(12), c = 19.46 0(6) Å, β = 95.605(24)°, V = 2698.2(11) Å3, Z = 4, Dcalc = 1.530 g/cm3 , R = 0.044, Rw = 0.036 based on 3218 reflections with I > 2σ(I); 2 (3)-1/2 hexane-1/2 CH3OH-1/2 H2O-1 CH2Cl2, monoclinic, C2/c, a = 41.766(10), b = 20.518(4), c = 16.784(3) Å, β = 101.871(18)°, V = 14076(5) Å3, Z = 8, Dcalc = 1.457 g/cm3, R = 0.064, Rw = 0.059 based on 5865 reflections with I > 2σ(I). Two independent cations were found in the asymmetric unit of the crystals of 3. The average distance between the Mo and the two η2-ligated carbon atoms is 2.574 Å in 1 and 2.581 and 2.608 Å in 3. The unfavourable disposition of the η2-phenyl group with respect to the metal centre in 3 and the rigidity of the η2-arene ligation excludes the possibility of any appreciable agostic C---H → Mo interaction.  相似文献   

17.
Infrared and Raman spectra for metal–string complexes M3(dpa)4X2 (M = Ni, Co, dpa = di(2-pyridyl)amido, and X = Cl, NCS) are studied. We assign the Ni3 asymmetric stretching vibration to infrared lines at 304 and 311 cm−1 for Ni3(dpa)2Cl2 and Ni3(dpa)2(NCS)2, respectively. A Raman shift at 242 cm−1 is assigned to the Ni3 symmetric stretching mode. For Co3 complexes a line for the Co3 asymmetric stretching mode appears at 313 and 331 cm−1 for Co3(dpa)2Cl2 and Co3(dpa)2(NCS)2, respectively.  相似文献   

18.
Two nickel (imidazole) complexes, Ni(im)6Cl2·4H2O (1) and Ni(im)6(NO3)2 (2) (im=imidazole) have been synthesized and characterized by elemental analysis, IR, UV, TG and single crystal X-ray diffraction. 1 crystallizes in the triclinic space group P-1 with a=8.800(6) Å, b=9.081(6) Å, c=10.565(7) Å, =75.058(9)°, β=83.143(8)°, γ=61.722(8)°, V=718.3(8) Å3, Z=1 and R1 (wR2)=0.0469 (0.1497). 2 crystallizes in the trigonal space group R-3 with a=12.370(6) Å, b=12.370(6) Å, c=14.782(14) Å, =90.00°, β=90.00°, γ=120.00°, V=1959(2) Å3, Z=3 and R1 (wR2)=0.0358 (0.0955). 1 and 2 exhibit different supramolecular network due to their different counter anions and different hydrogen bonding connection. In compound 1, [Ni(im)6]2+ cation and counter anions Cl alternatively array in an ABAB fashion via N–HCl hydrogen bonding. In compound 2, the plane of each NO32− is almost parallel and each NO32− connect three different [Ni(im)6]2+ cations via N–HO hydrogen bonding.  相似文献   

19.
为提高极性荧光指示剂Ru(dpp)3Cl2在非极性硅橡胶中的分散性,以沉淀白炭黑、气相白炭黑和甲基MQ树脂,载负荧光指示剂Ru(dpp)3Cl2,再填充到二甲基硅橡胶(PDMS)中,制备氧敏感荧光膜.以分光光度计和荧光光谱仪,研究载体种类对Ru(dpp)3Cl2的吸附性、荧光特性及氧敏感荧光膜性能的影响.白炭黑载负Ru(dpp)3Cl2的荧光发射光谱相对其稀溶液约红移20 nm.载体表面的甲基可减弱SiO2载体对Ru(dpp)3Cl2分子的吸附性和相互作用,减少荧光发射光谱的红移12 nm,提高荧光强度近10倍.白炭黑有助改善Ru(dpp)3Cl2在PDMS中的分散性和氧敏感荧光膜的荧光输出和猝灭比,尤以MQ树脂的效果最为显著.  相似文献   

20.
The X-ray crystal structures of (N,N′-bis-(o-amidobenzilidene)-1,3-diaminopropane)nickel (Niambpr), (N,N′-bis-(o-amidobenzilidene)-1,4-diaminobutane)nickel (Niambut), (N,N′-bis-(o-thiobenzilidene)-1,4-diaminobutane)nickel(II) (Nitsalbut), bis-acetonitrile-(N,N′-bis-(o-aminobenzyl)-1,2-diaminoethane) nickel(II) tetrafluoroborate [Ni(H4amben)(MeCN)2] [BF4]2, bis-O-acetato-(N,N′-bis-(o-aminobenzyl)-1,2-diaminoethane) nickel(II) [Ni(H4amben)(OAc)2 · H2O] and bis-O-acetato-(N,N′-bis-(o-aminobenzyl)-1,3-diaminopropane) nickel(II) [Ni(H4ambpr)(OAc)2] are presented. These structures complete the structural characterisation of the simple unsubstituted Schiff’s base complexes with N4 and N2S2 donor sets and allow us to assess the effects of donor groups and polymethylene chain length on the coordination geometries of nickel(II). The hydrogenated N4 complexes offer an insight into the effects of increased flexibility and character of the internal nitrogen donors. Unlike the parent N4 imine species the hydrogenated amine species do not deprotonate at the peripheral nitrogen donors and do not seem to be restricted to the meridial plane of the nickel.  相似文献   

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