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101.
Hydrosilylation of aromatic nitriles promoted by solvated rhodium atom-derived catalysts 总被引:1,自引:0,他引:1
Anna Maria Caporusso Nicoletta Panziera Paolo Pertici Emanuela Pitzalis Piero Salvadori Giovanni Vitulli Gianmario Martra 《Journal of molecular catalysis. A, Chemical》1999,150(1-2):275-285
Rhodium metal particles, isolated as supported or unsupported powder starting from mesitylene solvated rhodium atoms, catalyse the hydrosilylation of aromatic nitriles to N,N-disilylamines in high conversion at 100°C. Different hydrosilanes (HSiMe3, HSi(OEt)3) can be employed. In the case of cinnamonitrile, the chemoselectivity of the reaction to 2-trimethylsilyl-3-phenylpropionitrile and (E)- and (Z)-1-di(trimethylsilyl)amino-3-phenyl-1-propene is strongly dependent on the reaction temperature. The commercial rhodium on γ-Al2O3 catalyst is considerably less active and selective than the analogous catalyst prepared via Metal Vapour Synthesis (MVS) probably owing to the different dimension and distribution of the metal particles in the two samples as shown by HRTEM analysis. 相似文献
102.
Glushkov V. A. Ausheva O. G. Shurov S. N. Shklyaev Yu. V. 《Russian Chemical Bulletin》2002,51(5):894-896
1-R-3,3-Dimethyl-2-azaspiro[4.5]deca-1,6,9-trien-8-ones were synthesized through three-component condensation of anisole, isobutyraldehyde, and a corresponding nitrile in dichloromethane in the presence of concentrated sulfuric acid. 相似文献
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104.
A. N. Vasiliev Ya. S. Kayukov A. N. Lyshchikov O. E. Nasakin O. V. Kayukova 《Chemistry of Heterocyclic Compounds》2003,39(9):1182-1187
The reaction of alkyl 5,6-dialkyl-2-amino-3-cyano-4-pyridinecarboxylates with certain O-nucleophiles was investigated, as a result of which 6,7-dialkyl-4-amino-2,3-dihydro-1H-pyrrolo[3,4-c]pyridine-1,3-diones were synthesized. 相似文献
105.
The interaction of 2-amino-1,3,4-oxadiazole-5-carboxamidoxime with nitriles in the presence of ZnCl2 and HCl or with trichloroacetic anhydride affords 2-amino-5-(5R-1,2,4-oxadiazolyl-3)-1,3,4-oxadiazoles. Their reactions with N-nucleophiles have been studied.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2100–2103, December, 1993. 相似文献
106.
V. V. Dovlatyan K. A. Eliazyan V. A. Pivazyan E. A. Kazaryan A. P. Engoyan 《Chemistry of Heterocyclic Compounds》2002,38(9):1081-1083
The reaction of a mixture of formaldehyde and sodium cyanide or of lactic acid nitrile with trimethyl(6-methoxy-4-methylpyrimidinyl-2)ammonium chloride give the 2-(6-methoxy-4-methylpyrimidinyl-2-oxy)alkanoic acid nitriles. They were subsequently converted to the corresponding alkyl esters by a Pinner reaction and then to their 2-(5-halo-6-methoxy-4-methylpyrimidinyl-2-oxy) derivatives using N-halosuccinimides. 相似文献
107.
V. N. Yarovenko B. I. Ugrak M. M. Krayushkin V. Z. Shirinyan I. V. Zavarzin 《Russian Chemical Bulletin》1994,43(4):627-629
The structures of complexes formed during the transformation of amidoximes into 1,2,4-oxadiazoles by the action of nitriles in the presence of zinc chloride and HCl were studied by15N NMR spectroscopy.Translated fromIzyestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 676–678, April, 1994. 相似文献
108.
V. I. Kadentsev N. G. Kolotyrkina A. A. Stomakhin O. S. Chizhov 《Russian Chemical Bulletin》1995,44(9):1698-1704
Peculiarities of interaction of H+, Me3C+, and Me3Si+ ions with functional groups of molecules in the gas phase have been studied. Proton tends to form chelates with virtually all of the functional groups studied, whereas Me3Si+ ions exhibit no capacity for chelation. Using isomeric xylenes as examples it was shown that Me3Si+ ions (unlike Me3C+ ions) experience virtually no steric hindrance when they react with nucleophilic centers. Effects of functional groups present in molecules of nitriles on the generation of [M+Me3C]+ adducts in the gas phase and the Ritter reaction in solution were estimated.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1767–1773, September, 1995.This work was carried out with financial support from the International Science Foundation (Grant MA7 000) and the Russian Foundation for Basic Research (Project No. 93-03-18033). 相似文献
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