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Transition Metal Chemistry - New ruthenium(II) complexes with N-heterocyclic carbene ligand were synthesized by transmetalation reactions between silver(I) N-heterocyclic carbene complexes and...  相似文献   
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The heterogeneous esterification reaction of acrylic acid with hexanol over three different cation‐exchange resins, Amberlyst 131, Amberlyst 15, and Dowex 50Wx‐400, was investigated. Surface area, pore volume, average pore diameter, and acid capacity analyses were carried out for these three catalysts. Amberlyst 131 gave the highest conversion, and therefore, further experiments were performed catalyzed by Amberlyst 131. The absence of external and internal mass transfer resistances was investigated for the esterification of acrylic acid with hexanol. Experiments showed that the reaction is controlled by chemical step rather than external and internal mass transfer steps. The effects of temperature, catalyst loading, and alcohol to acid molar ratio on the conversion of acrylic acid were determined. The activation energy and kinetic and adsorption constants were determined according to the Langmuir–Hinshelwood–Hougen–Watson mechanism.  相似文献   
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N'-[4'-benzo(15-crown-5)]-4-tolylaminoglyoxime (H2L1),the sodium chloride salt of H2L1 (H2L1...NaCl),N'-[4'-benzo(15-crown-5)]-4-chlorophenylaminoglyoxime(H2L2) and the sodium chloride salt of H2L2 (H2L2...NaCl)have been prepared from p-chlorophenylchloroglyoxime,p-tolylchloroglyoxime, 4'-aminobenzo[15-crown-5] and sodiumbicarbonate or sodium bicarbonate and sodium chloride. Nickel (II),cobalt (II) and copper (II) complexes of H2L and H2L...NaClhave a metal-ligand ratio of 1 : 2 and the ligand coordinatesthrough the two N atoms, as do most of the vic-dioximes. Their IR spectra and elemental analyses are given, together with1H NMR spectra of the ligands.  相似文献   
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Four unsymmetrical vic-dioximes: [L1H2] N-(4-butylphenyl)amino-amphi-glyoxime, [L2H2] N-(4-butylphenyl)amino-anti-glyoxime, [L3H2] N-(4-phenylazophenyl)amino-amphi-glyoxime and [L4H2] N-(4-phenylazophenyl)amino-anti-glyoxime have been prepared from amphi-chloroglyoxime, anti-chloroglyoxime, 4-butylaniline and 4-(phenylazo)aniline respectively. The complexes of these vic-dioximes with NiII, CoII, CuII and CdII ions have been investigated. All are insoluble in common solvents. Their i.r. spectra and elemental analyses are given, together with mass and 1H-n.m.r. spectra of the ligands.  相似文献   
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Research on Chemical Intermediates - Metal complexes of thiosemicarbazones have been receiving considerable attention in biological applications such as antimicrobial and anticancer therapies. In...  相似文献   
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