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1.
EPR studies have been carried out on solutions of the complexes [Cu(trien)NCS](NO3), [Cu(trien)I]I, [Cu(Me6trien)NCS]B?4 and [Cu(Me6trien)](ClO4)2, (trien = 1,4,7,10-tetraazadecane; Me6trien = hexamethyl trien) in different solvents to investigate the solute-solvent interactions. From calculations of the 4s contribution in the ground state and bond parameters it is found that the axial bond in [Cu(trien)NCS](NO3) dissolved in pyridine is weaker than that in the other complexes dissolved in different solvents. For the two methylated complexes, in spite of the +I effect of the methyl group, the in-plane copper-nitrogen bonds are found to be weak, which is probably due to the changes in structure caused by methylation. 相似文献
2.
J.S. Yadav B.V. Subba Reddy P. Vishnumurthy Ch. Janardhana Chary 《Tetrahedron letters》2007,48(33):5915-5918
Lithium tetrafluoroborate is found to be an efficient catalyst for allylation and cyanation of aldehydes with allyltrimethylsilane and trimethylsilyl cyanide in the presence of acetic anhydride at room temperature to produce homoallylic acetates and α-cyano acetates in excellent yields. A solution of 10 mol % of LiBF4 in acetonitrile provides a convenient reaction medium to carry out allylation and cyanation reactions under very mild and neutral conditions. 相似文献
3.
Chary KV Sagar GV Naresh D Seela KK Sridhar B 《The journal of physical chemistry. B》2005,109(19):9437-9444
A series of copper catalysts supported on TiO2-ZrO2 with copper loading varying from 1.0 to 21.6 wt % were prepared by a wet impregnation method. The catalysts were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), UV-vis diffuse reflectance spectroscopy, electron spin resonance (ESR), temperature programmed reduction (TPR), and Brunauer-Emmett-Teller specific surface area measurements. Copper dispersion and metal area were determined by N2O decomposition by the passivation method. XRD results suggest that the copper oxide is present in a highly dispersed amorphous state at copper loadings <16.8 wt % in the sample and as a crystalline CuO phase at higher Cu loadings. Copper dispersion increases with Cu loading up to 5.1 wt % and levels off at higher loadings. The XPS peak intensity ratios of Cu 2p(3/2)/Ti 2p(3/2) and Cu 2p(3/2)/Zr 3d(5/2) were compared with the copper dispersion calculated from N2O decomposition. ESR results suggest the presence of two types of copper species on the TiO2-ZrO2 support. TPR profiles reveal the presence of highly dispersed copper oxide at lower temperatures and bulk CuO at higher temperatures. The catalytic properties were evaluated for the vapor-phase dehydrogenation of cyclohexanol to cyclohexanone and related to the dispersion of Cu on TiO2-ZrO2. 相似文献
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A practical & cheaper reagent system ZrCl4/NaBH4 is used for the production of amines from azldes is described. 相似文献
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Reductive cleavage of acetals/ketals with zirconium tetrachloride-sodium borohydride leading to the formation of ether alcohols is described. 相似文献
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A rapid and efficient method for the preparation of 3‐(4,6‐dimethyl‐oxazolo[4,5‐c]quinolin‐2‐yl)‐chromen‐2‐ones by the reaction between 3‐amino‐2,8‐dimethyl‐quinolin‐4‐ol and 2‐oxo‐2H‐chromen‐3‐carboxylic acid using sulfamic acid as a acid catalyst and dimethyl formamide as a solvent using the conventional method and microwave irradiation is reported. 相似文献
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