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51.
Two new copper(II) complexes were synthesized by reaction of N-(3-aminopropyl)benzylamine (L1: apba, for complex 1) and N-salicylidene-apba (L2: for complex 2) with Cu2+. Crystals of complex 1 were orthorhombic, space group pccn, with a?=?15.2149(10), b?=?25.0071(16), c?=?7.6280(5)?Å and α?=?β?=?γ?=?90°. Complex 2 crystals were monoclinic, space group P21/c, with a?=?8.688(6), b?=?12.812(9), c?=?16.022(11)?Å and β?=?99.241(10)°. Structures of the two complexes were centro-symmetric and both Cu(II) atoms were four coordinate with a distorted square-planar geometry. The toxicity of the complexes was evaluated by testing antimicrobial activity against bacterial strands.  相似文献   
52.
Reactions of copper(I) halides with triphenyl phosphine in acetonitrile followed by the addition of salicylaldehyde N-ethylthiosemicarbazone {(2-OH–C6H4)(H)C2=N3–N2H–C1(=S)N1HEt, H2stsc-NEt} in chloroform in 1?:?2?:?1 (Cl) or 1?:?1?:?1 (Br, I) molar ratios yield mononuclear, [CuCl(η 1-S-H2stsc-NHEt)(PPh3)2] (1) and sulfur-bridged dinuclear, [Cu2X2(μ-S-H2stsc-NEt)2(PPh3)2] (X?=?Br, 4; I, 5) complexes. Similarly, reaction of silver halides (Cl, Br) with H2stsc-NEt in acetonitrile followed by the addition of PPh3 to the solid that formed (1?:?1?:?2 molar ratio), yielding mononuclear complexes, [AgX(η 1-S-H2stsc-NHEt)(PPh3)2] (Cl, 2; Br, 3). All these complexes are characterized with analytical data, IR, and NMR spectroscopy and single-crystal X-ray crystallography. The ligand favored η 1-S bonding in 1, 2, and 3, and μ-S bonding in 4 and 5. Cu?···?Cu contacts were 3.063?Å. The complexes form 1-D or 2-D H-bonded networks, entrapping solvent in some cases.  相似文献   
53.
Abstract

A method for the spectrophotometric determination of cobalt (II) by complexation with di-2-pyridyl ketone benzoylhydrazone (DPKBH) in 50% (v/v) ethanolic solution is described. Cobalt (II) forms a 1:2 complex with DPKBH. The complex has maximum absorbance at 370 nm. Beer's law is obeyed over the range 0.1 – 2.8 μg.ml?1. The effect of pH, effect of excess reagent, stability of the complex and the tolerance limit of many metal ions have been reported. The method is applied to the determination of cobalt in different alloys containing other metals ions.  相似文献   
54.
A series of binuclear palladium(II) salicylaldiminato dithiosemicarbazone complexes have been synthesized and characterized. The palladium complexes were obtained by the reaction of various ethylene- and phenylene-bridged dithiosemicarbazones with Pd(PPh3)2Cl2. The free salicylaldimine ligands and their palladium complexes were characterized by NMR and IR spectroscopies, ESI-mass spectrometry, elemental analyses and for two representative complexes also by X-ray diffraction. In both metal complexes, the solid-state structures show the two palladium centers to be coordinated in a slightly distorted square-planar geometry, which gives rise in each case to five- and six-membered chelate rings. The salicylaldimine thiosemicarbazone ligands coordinate to palladium in a tridentate manner, through the phenolic oxygen, imine nitrogen and thiolate sulfur atoms.  相似文献   
55.
水杨醛的电合成法   总被引:1,自引:0,他引:1  
水杨酸经电解还原合成水杨醛已有报道,但其收率不超过50%.我们改进了实验条件,成功地将收率提高到70%以上,实验重现性好.产物经色谱分析,其纯度大于96%.具体方法如下: 将14g水杨酸、5g亚硫酸氢钠及其它助电解质溶于350mL水,配成的阴极液置于一作为阴  相似文献   
56.
铝-水杨醛苯甲酰腙荧光反应的研究及应用   总被引:3,自引:0,他引:3  
本文研究了Al~(3+)-水杨醛苯甲酰腙高灵敏度荧光体系,络合物的荧光激发波长=375nm,发射波长=450nm。铝量在0~1.4μg/10ml范围内,荧光强度与其含量成正比,灵敏度为0.4ppb。方法可用于试剂中微量铝的检测,结果令人满意。  相似文献   
57.
The reaction of 2-hydroxybenzaldehydes with alkanols in the presence of triphenylphosphine and di-tert-butyl azodicarboxylate (DBAD), under the Mitsunobu reaction conditions, gives rise to the formation of hydrazones as the major products rather than the expected alkyl aryl ethers.  相似文献   
58.
Eight diorganotin(IV) complexes of salicylaldehyde isonicotinylhydrazone (H2SalN) R2Sn(SalN) R = t-Bu 1, Ph 2, PhCH23, o-ClC6H4CH24, p-ClC6H4CH25,m-ClC6H4CH26,o-FPhCH27, p-FC6H4CH28 were prepared. All complexes 1-8 have been characterized by elemental, IR, 1H, 13C and 119Sn NMR analyses. The crystal structures of H2SalN and complex 1 were determined by X-ray crystallography diffraction analyses. Studies show that H2SalN is a tridentate planar ligand. For complex 1, the tin atom lies in this plane and forms a five- and six-membered chelate ring with the tridentate ligand. A comparison of the IR spectra of the ligand with those of the corresponding complexes, reveals that the disappearance of the bands assigned to carbonyl unambiguously confirms that the ligand coordinate with the tin in the enol form.  相似文献   
59.
A convenient and efficient procedure for one‐pot preparation of double Schiff bases through a three component reaction of salicylaldehyde, ammonium acetate and aliphatic aldehyde was described. In this reaction, N,N′‐bis(salicylidene)‐1,1‐diaminoalkanes was easily obtained in excellent yields and short reaction times under mild reaction condition.  相似文献   
60.
[BrMn(CO)5] reacts with benzoylhydrazine in THF occurring substitution of two CO groups by a Metal‐ligand ring to give fac‐[Mn(Br)(CO)3(BHD)]·2THF (BHD = C6H5CONHNH2). The novel compound shows a distorted octahedral arrangement at the manganese atom, with three nearly linear carbonyl ligands in a fac arrangement, illustrating another example that the CO group in position trans to the bromine ligand in [BrMn(CO)5] presents the most intensive metal‐CO backbonding effect of all the CO groups of the parent complex, leading to the formation of a facial (and not meridional) isomer, even in the presence of a bidentate ligand like benzydrazide. X‐ray measures of yellow crystals showed that the title complex belong to space group P21/c, with the asymmetric unit containing one crystallographically independent [Mn(Br)(CO)3(BHD)] complex and two tetrahydrofurane solvate molecules. The new compound represents heretofore the unique occurrence of the complexing single bidentate ligand ‐O=C(Ph)‐N(H)‐N(H)2‐ with an octahedral coordination at the MnI atom supported chiefly by carbonyl groups.  相似文献   
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