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排序方式: 共有240条查询结果,搜索用时 46 毫秒
1.
Pan Huang Dawen Xu Robert M. Reich Felix Kaiser Boping Liu Fritz E. Kühn 《Tetrahedron letters》2019,60(24):1574-1577
A first example of an Et2Zn mediated silylation of 1-aklynes is reported. A series of functional groups are tolerated in this reaction. Mechanistic studies support Zn alkynilides as intermediates in the reaction. This reaction protocol provides a practical method for the preparation of alkynylsilanes and expands the application of organometallic zinc in organic synthesis. 相似文献
2.
A rapid method for the derivatization of phenolic antioxidants using microwave irradiation has been developed. Six antioxidatively active phenolic components of wines and fruits, namely gallic acid, gentisic acid, vanillic acid, caffeic acid, ferulic acid and p-coumaric acid were used in the model study. The solution of phenolic acids was evaporated to dryness on a rotary evaporator followed by further drying under microwave irradiation (600 W, 30 s). The resultant residue was dissolved in pyridene and treated with bis(trimethylsilyl)acetamide while irradiated by microwave using high power for 30 s. Controlled reaction was carried out employing bis(trimethylsilyl)trifluoroacetamide under conventional heating for 30 min. The trimethylsilyl derivatives were identified and quantified on a gas chromatography/mass selective detector. The mass spectral fragmentation patterns of the derivatives obtained by microwave irradiation were identical to those prepared by heating. The yields of microwave-assisted silylation were comparable to those from conventional heating. The rsd were less than 8% for six replicates. The linearity in wine matrix was nearly perfect. This method is a useful protocol to examine the phenolic constituents in wines and agricultural products. 相似文献
3.
A. R. Burilov D. V. Cherepachkin I. L. Nikolaeva M. A. Pudovik 《Russian Chemical Bulletin》1995,44(2):345-349
Some newS-phosphorylated,S-silylated, andS-stannylated derivatives of -mercaptoketones were obtained. The reactions of some of these compounds induced by the temperature and by molecular oxygen as well as the phosphorylation of the Si- and Sn-containing derivatives were studied.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 353–357, February, 1995. 相似文献
4.
A. V. Lesiv S. L. Ioffe Yu. A. Strelenko V. M. Danilenko 《Russian Chemical Bulletin》2004,53(10):2233-2240
Coupling of N,N-bis(silyloxy)enamines with tertiary amines and nitrogen-containing heterocycles affording the corresponding functionalized ammonium or iminium salts was studied. The area of its application was determined, and optimal procedures for the synthesis of the target products were proposed. The mechanism including the formation of conjugated nitroso alkene or a silylnitrosonium cation as key intermediates is discussed.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2137–2143, October, 2004. 相似文献
5.
A. Zablotskaya I. Segal S Germane I. Shestakova I. Domracheva A. Nesterova A. Geronikaki E. Lukevics 《Chemistry of Heterocyclic Compounds》2002,38(7):859-866
Trimethylsilyl ethers of various hydroxyl-containing thiazole derivatives have been synthesized. The psychotropic activity (in vivo) and the cytotoxicity (in vitro on tumor cell lines HT-1080 and MG-22A) of these ethers and of their unsilylated precursors have been studied. It was discovered that the obtained compounds possess a sedative action. A moderate cytotoxic effect was detected for piperidine-containing thiazoles, displayed most strongly in relation to MG-22A cells. 相似文献
6.
7.
The reactions of (lithiomethyl)furazans with chlorosilanes were investigated and a number of silyl derivatives of methylfurazans were prepared. The reactivity of these compounds was studied. 相似文献
8.
K. Yu. Chegaev A. N. Kravchenko O. V. Lebedev Yu. A. Strelenko P. A. Belyakov 《Chemistry of Heterocyclic Compounds》2002,38(10):1250-1252
N-Trimethylsilyl derivatives of 2,4,6,8-tetraazabicyclo[3.3.0]octane-3,7-diones have been prepared for the first time and the electrophilic substitution reaction of the trimethylsilyl group has been studied. 相似文献
9.
Jeroen W. Sprengers Marcel A. Duin Cornelis J. Elsevier 《Journal of organometallic chemistry》2003,679(2):149-152
A highly active and selective in situ formed platinum(N-heterocyclic carbene) catalyst for the hydrosilylation of styrene with triethylsilane is described, which unlike all other known hydrosilylation catalysts, selectively yields hydrosilylation products, but (almost) no dehydrogenative silylation products. 相似文献
10.
Batool Akhlaghinia Mozafar Asadi Elham Safaee Mozhgan Heydarpoor 《Phosphorus, sulfur, and silicon and the related elements》2013,188(10):2099-2104
Alcohols and phenols are protected with hexamethyldisilazane in the presence of N,N′,N′,N?-tetramethyletra-2,3-pyridinoporphyrazinato copper (II) in good-to-excellent yields at room temperature. 相似文献