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81.
82.
室温固相反应;丙二腈类化合物的室温固相合成、结构及单双光子荧光性质  相似文献   
83.
Summary A series of metal (Cu, Ni, Zn, Cd and Pd) complexes of a Schiff base ligand derived from S-benzyldithiocarbazate and p-nitrobenzaldehyde were prepared and characterized. The Schiff base acts as a single negatively-charged bidentate ligand forming stable neutral metal complexes. Magnetic and spectroscopic data suggest a square planar structure for the CuII, NiII and PdII chelates. Single X-ray diffraction analysis of the NiII chelate established that the Schiff base loses a proton from its tautomeric thiol form and coordinates to the metal via the thiolato sulfur and -nitrogen. The geometry around NiII is square planar with two equivalent Ni-N and Ni-S bonds; the two nitrobenzyl rings and the coordination plane are almost isoplanar, giving a delocalized electronic system.  相似文献   
84.
Mannich aminomethylation reactions involving M(aa)2, where M = Cu, Ni and aa = glycine(gly), dl-alanine(dl-ala), l-alanine(l-ala), with formaldehyde and diethylmalonate have been carried out, resulting in carboxylate appended systems in high yield. All the compounds have been characterized by UV-Vis spectroscopy, infrared spectroscopy and elemental analysis. One of the synthesized complexes, (5,5-dicarboxyethyl-3,7-diazanonanedioato)copper(II) monohydrate, has been characterized by single crystal XRD and has been used as catalyst in the hydrogen peroxide-induced degradation of pyrocatechol violet (PCV) dye. The variations in the rate of degradation of the dye with respect to change in concentration of hydrogen peroxide, dye, catalyst and pH have been studied. Effect of addition of NaCl has been studied and a suitable mechanism based on the formation of free radical species during the degradation process has been proposed.  相似文献   
85.
X-射线晶体结构分析表明,在90℃的水热条件下,N-(8-喹啉基)吡啶-3-酰胺在Cd2+的存在下发生醇解.醇解产物为8-氨基喹啉(HL1)和吡啶-3-羧乙酯(HL2),它们与Cd (Ⅱ)配位形成四方锥型化合物.该配合物为单斜晶系,空间群P21/c.a=18.1089(1)A,b=8.9986(1)A,c=19.3070(2)A,β=113.085(1)和Z=4.  相似文献   
86.
Photooxygenations of 1,2-, 1,3-, and 2,3-di- and 1,2,3-trisubstituted indolizines 1a-1f under different reaction conditions in methanol and acetonitrile have been investigated to establish the general reaction pattern and mechanism in indolizine photooxygenation in view of the influence of the ring substituents and substitution pattern. Photooxygenations of 1-acyl-2-phenylindolizines 1a and 1b and 1,3-dibenzoyl-2-phenylindolizine (1d) are self-sensitized, while those of 1-(p-nitrobenzoyl)-2-phenylindolizine (1c) and 2-phenyl-3-(p-chlorobenzoyl)indolizine (1e) need to be sensitized by rose bengal (RB) or methylene blue (MB). These reactions proceed via a singlet oxygen mechanism yet follow different pathways in methanol and in acetonitrile, with peroxidic zwitterion D (in methanol) and dioxetane E across the indolizine C2-C3 bond (in acetonitrile) as the intervening intermediates. Methanol trapping of the peroxidic zwitterion results in C3-N bond cleavage and pyrrole ring opening to give the corresponding (E)- and (Z)-3-(2-pyridinyl)-3-benzoylpropenoic acid methyl esters (2 and 3) and 4-(2-pyridinyl)-3-phenyl-5-aryl-5-hydroxyfuran-2-one (4) as products in methanol, while O-O bond homolysis of the dioxetane furnishes 3-(2-pyridinyl)-3-benzoyl-2-phenyloxirane-2-carboxaldehyde (6) and 1-(6-methyl-2-pyridinyl)-2-phenylethanedione (5) as products in acetonitrile. 3-Benzoyl-1-indolizinecarboxylic acid methyl ester (1f) is unreactive toward singlet oxygen; however, it could be photooxygenated under electron transfer conditions with 9,10-dicyanoanthracene (DCA) as a sensitizer. This reaction takes place by the combination of the indolizine cation radical with the superoxide anion radical (or molecular oxygen) to give the pyridine ring oxidized methyl 3-benzoyl-5-methoxy-8-hydroxy-1-indolizinecarboxylate (9f), dimethyl 2-(2-pyridinyl)fumarate (8f), and dimethyl 2-(2-pyridinyl)maleate (7f) as products.  相似文献   
87.
The spectral studies and structure of a ternary complex of copper(II) with 2-hydroxyacetophenone 3-hexamethyliminylthiosemicarbazonate (L(2-)) and 1,10-phenanthroline (phen) are reported. The thiosemicarbazone binds to the metal as a dianionic ONS-donor (L(2-)) ligand, and forms a complex of the stoichiometry [CuLphen]. The copper(II) complex was characterized by IR and UV/Vis spectroscopies, as well as by solid state room-temperature magnetic susceptibility. Spin Hamiltonian and bonding parameters of the compound are calculated from the EPR spectra. Computer simulation of EPR spectrum in DMF at 77 K aided the calculation of magnetic and bonding parameters of the compound. The structure of the compound is solved by single crystal X-ray diffraction. The geometry around copper is distorted square pyramidal.  相似文献   
88.
Shen  Zhen  Zuo  Jing-Lin  Shi  Fa-Nian  Xu  Yan  Song  You  You  Xiao-Zeng  Raj  S. Shanmuga Sundara  Fun  Hoong-Kun  Zhou  Zhong-Yuan  Che  Chi-Ming 《Transition Metal Chemistry》2001,26(3):345-350
Two bimetallic assemblies, K2[NiII(cyclam)]3[FeII(CN)6]2 · 12H2O (1) and [NiII(cyclam)]3[FeIII(CN)6]2 · 16H2O (2) (cyclam = 1,4,8,11-tetraazacyclotetradecane), were obtained by reaction of K4[Fe(CN)6] and [Ni(cyclam)](ClO4)2 in aqueous media at different temperatures. Their crystals were structurally determined and magnetic properties were studied. Both of the compounds have honeycomb-layered structures, which are formed by Fe6Ni6 units linked through the cyanide bridges. Structure (1) consists of polyanions containing NiII–NC–FeII linkages and K+ cations, while structure (2) is a two-dimensional neutral layer containing NiII–NC–FeIII linkages. The magnetic properties of (1) and (2) have been investigated in the 5–300 K range. Compound (1) exhibits a weak antiferromagnetic interaction with Weiss constant = –0.35 K; compound (2) shows ferromagnetic intralayer and antiferromagnetic interlayer interactions.  相似文献   
89.
The title complex [Mn2(phen)4(FCA)2](ClO4)2·H2O (1) (FCA = dianion of 3-ferrocenyl-2-crotonic acid, phen = 1,10-phenanthroline) has been prepared, and its structure determined by single crystal X-ray diffraction analysis. The structure consists of a dinuclear cation [Mn2(phen)4(FCA)2]2+, non-coordinated perchlorate anions and a water molecule. The two MnII ions are separated by 4.374 Å in the cation and are dicarboxylate-bridged by carboxylate ligands containing ferrocenyl units. Each FCA is bound to two MnII ions through carboxylate oxygens with the synanti bridging mode. The MnII ion is coordinated in an octahedral N4O2 geometry by two chelate phen ligands and two -carboxylate oxygen atoms. Electrochemical properties of (1) are discussed.  相似文献   
90.
The mol­ecule of the title compound, methyl 1-formyl-6-oxa-6H-indene-4-carboxyl­ate, C11H8O4, is planar. There are weak C—H⋯O intramolecular interactions and an intermolecular hydrogen bond in the structure, and these influence the crystal packing.  相似文献   
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