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101.
A new series of group 6 carbonyl complexes of N-[(2-pyridyl)methyliden]-α (or β)-aminonaphthalene (α/β-NaiPy) are described in this work. The complexes are formulated as cis-[M(CO)4(α/β-NaiPy)] by elemental, mass and other spectroscopic data. The complexes show emission spectra at room temperature and their quantum yield lies between 0.4 and 0.5. All the complexes exhibit negative solvatochromism. Cyclic voltammetry shows metal centred oxidation and ligand reductions. 相似文献
102.
The reactions of β-naphthol with 5-diazoimidazoles and imidazolyl-5-diazonium salts containing chemically different carboxamide
groups in position 4 were studied. Heterocyclization of 4-arylcarbamoyl-5-(2-hydroxynaphthylazo)imidazoles formed in these
reactions was investigated. The presence of the NH fragment in the amide group prevents this process, the reaction giving
instead 3-substituted 3,7-dihydroimidazo[4,5-d][1,2,3]triazin-4-ones, which is due to reversibility of C-azo coupling. Methods for modification of 1-ethoxycarbonyl group in the naphtho[2,1-e]imidazo[5,1-c][1,2,4]triazine system were developed and used to prepare substituted carboxamides inaccessible by other routes.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1208–1213, July, 2006. 相似文献
103.
5-Amino-4-cyano-8-isobutyl-7-isopropyl-6-thiocarbamoyl-2-azabicyclo[2.2.2]oct-5-en-3-thione was synthesized by the condensation of isovaleryl aldehyde with cyanothioacetamide. The structure of the product was established by X-ray crystallography. 相似文献
104.
Paul D. Beer Zheng Chen Philip A. Gale Jennifer A. Heath Rachel J. Knubley Mark I. Ogden Michael G. B. Drew 《Journal of inclusion phenomena and macrocyclic chemistry》1994,19(1-4):343-359
The synthesis, metal, ammonium and alkyl ammonium cation coordination chemistry and electrochemical recognition studies of new diester-and diamide-calix[4]arenediquinone receptors are described. In addition the synthesis and coordination properties of a novel diamide benzo-15-crown-5-calix[4]arene molecule is reported.This paper is dedicated to the commemorative issue on the 50th anniversary of calixarenes. 相似文献
105.
V. G. Avakyan N. A. Kubasova É. Kh. Kurasheva I. A. Musaev 《Russian Chemical Bulletin》1992,41(9):1628-1634
The conformations and heats of formation of all trans(T)- and cis(C)-2- and 3-methyl-substituted T- and Cbicyclo[4.4.0]decanes (BD) were calculated by the MM2 method of molecular mechanics. It was shown that the conformationally mobile T-2-Me-CBD and T-3-Me-CBD can exist in normal conditions as an inseparable mixture of conformers with a different equatorial or axial orientation of the Me groups. The Raman scattering (RS) spectra of TBD and CBD were investigated. RS bands whose frequencies were sensitive to the type of ring linkage and orientation (but not the position) of the Me substituents were detected in the 700–300 cm–1 region.A. V. Topchiev Institute of Petrochemical Synthesis, Russian Academy of Sciences, 117912 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 9, pp. 2089–2097, September, 1992. 相似文献
106.
Under various basic solutions and reaction durations, 3-substituted 4-formyIsydnones and nitroalkanes containing α-active hydrogen (e.g. nitromethane and nitroethane) are converted to β-nitroalcohols, nitroalkenes and dinitroalkanes. β-Nitroalcohols are obtained only by electrochemical reaction on an electrogenerated base (EGB). The mechanism of overall reaction steps in particular is discussed. 相似文献
107.
Cd2+ complexes with antibiotics viz. neomycin, chlortetracycline, oxytetracycline, tetracycline, penicillin‐V and penicillin‐G as primary ligands and vitamin‐B5 as secondary ligand have been reported at pH = 7.30 ± 0.01 and μ = 1.0 M KNO3 at 298 K by polarographic technique.1 Cd2+ formed 1:1:1, 1:1:2, and 1:2:1 complexes with a stability constants trend of neomycin < chlortetracycline < oxytetracycline < tetracycline < penicillin‐V < penicillin‐G can be explained on the basis of the nature of ligands, bonding, and steric hindrance of these drugs. The nature of electrode processes were reversible and diffusion controlled. The values of stability constants showed that these drugs can be used to reduce the toxicity of Cd. 相似文献
108.
We have developed a novel regioselective method for synthesis of substituted spiro([1]benzopyran-2,4'-(1'H)pyrimidine)-2'-(3'H)thiones and spiro([1]benzopyran-2,4'-(1'H)pyrimidin)-2'-(3'H)ones having one or two hydroxyl groups on the benzene ring. 相似文献
109.
Synthesis and binding studies of new bis-calix[4]arenes containing aromatic and heteroaromatic units
A series of new bis-calix[4]arenes containing different aromatic and heteroaromatic moieties have been synthesized. The complexing behavior of these bis-calix[4]arenes have been studied towards different metal ions and it has been found that these bis-calix[4]arenes bind silver ions selectively over other metal ions. The complexation has been studied by liquid-liquid extraction and by NMR and IR spectroscopy. 相似文献
110.
K3 [Fe(CN)6] and KFe[Fe(CN)6] are classical coordination compounds. However, the mechanism of decomposition reactions has not been well expounded. The gas products of thermal decomposition were examined by gas chroma tography (GC) , and the structure of the solid products by Mossbauer spectroscopy(MS) and X-ray diffraction(XRD). The findings are explained in terms of the theory of coordination chemistry and a decomposition mechanism is proposed in this study. On the basis of various experimental results, the first stage of the decomposition of K3[Fe(CN)6] in He was found to be the evolution of(CN)2 resulting in the reduction of Fe(Ⅲ)12K3 [Fe(CN)6]→9K4[Fe(CN)6] + Fe2 [Fe(CN)6] + 6 ( CN )For KFe [Fe(CN) 6 ], the first stage of decomposition man be represented as6KFe[Fe(CN)6]→3K2Fe[Fe(CN)6] + 2Fe2[Fe(CN)6 + 3(CN)2At higher temperatures, the decomposition of both K3[Fe(CN)6) andKFe[Fe(CN)6] to form KCN and Fe2C was accomplished by the release of(CN)2 and N2. 相似文献