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131.
Donnelly PS Zanatta SD Zammit SC White JM Williams SJ 《Chemical communications (Cambridge, England)》2008,(21):2459-2461
The CuI complex of the 'click' ligand tris(benzyltriazolylmethyl)amine is an unusual dinuclear dication with one triazole unit bridging two metal centers, and is an effective catalyst for the 'click' cycloaddition reaction. 相似文献
132.
Nilo Cornejo Luis Pascual Aitana Tamayo Fausto Rubio Mª. Angeles Rodríguez Juan Rubio 《Journal of Non》2012,358(22):3028-3035
The presence of minor elements on the crystallization kinetics of iron-rich glass obtained from a Ni–Cu–Co mining waste has been investigated. Two glasses named WG2 and RG were melted at 1500 °C. WG2 was prepared by using the mining waste, whereas RG contains pure oxides and no minor elements. WG2 and RG glasses presented high tendency toward crystallization with KH coefficients of 0.21 and 0.29, respectively. Due to the presence of minor elements WG2 crystallizes at lower temperatures than RG glass leading to an increase in the viscosity. Crystallization kinetics analyzed by different models gives activation energy values close to 500 and 400 kJ·mol? 1 for WG2 and RG, respectively. The Avrami parameter, n, depends on the particle size used for measurement and indicates the high tendency toward surface crystallization for both glasses. 相似文献
133.
Helio G. Bonacorso Liliane M.F. Porte Gisele R. Paim Fabio M. Luz Marcos A.P. Martins Nilo Zanatta 《Tetrahedron letters》2010,51(29):3759-3761
In this study, the versatile diethylaminosulfur trifluoride (DAST), a well-known fluorinating agent, was applied in the dehydration, intramolecular cyclization, and mono- and difluorination reactions of some 5-trifluoromethyl-1H-pyrazoles and 2-pyrazolines employing a general, mild, and efficient methodology. The azole precursors were synthesized from the reactions of acyclic and cyclic trifluoroacetylated enol ethers with hydrazines [NH2NHR, where R = C6H5, C6F5, 2-Furanoyl] and showed a differentiated chemical behavior in the presence of DAST. 相似文献
134.
Helio G. Bonacorso Rosália Andrighetto Nilo Zanatta Marcos A.P. Martins 《Tetrahedron letters》2010,51(29):3752-3755
The unexpected results of the cyclization reactions of N,N′-bis(oxotrifluoroalkenyl)-1,3-phenylenediamines [1,3-C6H4-(NHCRCHC(O)CF3)2], where R = H, Me, and Ph, in a strongly acidic medium (PPA), allowing the synthesis of new trifluoromethylated heterocycles containing the 1,7-phenanthroline nucleus in 32-40% yields and 7-aminoquinolines (38-40% yields), is reported. The bis-enaminoketone intermediates were easily isolated from the reactions of 4-alkoxy-4-alkyl(aryl)-1,1,1-trifluoroalk-3-en-2-ones with 1,3-phenylenediamine in ethanol under mild conditions (68-86% yields). 相似文献
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