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131.
V. V. Yanilkin N. I. Maksimyuk E. I. Gritsenko Yu. M. Kargin 《Russian Chemical Bulletin》1992,41(8):1363-1367
By analyzing the kinetics of heterogeneous (electrode) and homogeneous reduction for benzyl phenyl ether it was found that toluene and phenol are formed via the transfer of two electrons and the breaking of the PhO-Bz bond. It was shown that electron transfer constitutes the slow stage in heterogeneous and homogeneous reduction. The homogeneous transfer coefficient was approximately 0.5, which represents a significant difference from the heterogeneous value.A. E. Arbuzov Institute of Organic and Physical Chemistry, Kazan's Scientific Center, Russian Academy of Sciences, 420083 Kazan'. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 8, pp. 1760–1765, August, 1992. 相似文献
132.
YANG Bing-Hui JIANG Ji-Qing HUANG Xiao-Lin WU Hou-MingState Key Laboratory of Bio-organic Natural Products Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai China 《中国化学》1997,15(2):178-187
This reaction provided an efficient method to synthesize C-furanoside derivatives in high yields and stereospecificity under mild conditions.The cyclization mechanism regarding benzyl group as a leaving group was discussed and their stereochemistry was deduced by 1H-1H NOESY data. 相似文献
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Regeneration of Carbonyl compounds from the corresponding thioketals in nitrogen heterocycles have been effected using Dowex 50W acidic catalyst in reasonable yields. 相似文献
135.
NaIO4/LiBr‐Mediated Direct Conversion of Benzylic Alcohols and Aromatic Aldehydes to Aromatic Esters
Aromatic aldehydes or benzylic alcohols are directly converted to the corresponding aromatic esters in high yields on treatment with methanol or ethanol mediated by sodium metaperiodate (NaIO4)/LiBr in an acidic medium. 相似文献
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In the presence of cobalt (III) salen complex, selective oxidation of alcohols to carbonyl compounds was studied by molecular oxygen using isobutyraldehyde as an oxygen acceptor. The effect of cobalt (III) salen complex in the oxidation reaction was studied, and the results showed that Co (III) salen complex is very active and selective in the oxidation of various alcohols. Also, the effect of important factors including catalyst amount, solvent and temperature was investigated on the reaction. Furthermore, the catalytic activities of CoFe2O4@SiO2‐supported Schiff base metal complex as well as the effect of molecular oxygen (O2) as a green oxidant were studied. The results showed that benzaldehyde was the major product and the heterogeneous catalyst was highly reusable. 相似文献
140.
During the last years (2000–2014), many publications concerning the forensic analysis of questioned documents have been published, and new techniques and methodologies are nowadays employed to overcome forensic caseworks. This article reviews a comprehensive collection of the works focused on this issue, including dating studies, the analysis of inks from pens and printers, the analysis of paper, the analysis of other samples related to questioned documents and studies on intersecting lines. These sections highlight the most relevant analytical studies by a wide range of analytical techniques. Separation and spectrometric techniques are critically discussed and compared, emphasizing the advantages and disadvantages of each one. Finally, concluding remarks on the research published are included. 相似文献