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221.
Maryam Mirza-Aghayan Mahdi Alizadeh Mahdieh Molaee Tavana Rabah Boukherroub 《Tetrahedron letters》2014
A simple, efficient, and general procedure for the ring-opening of epoxides with various alcohols to give the corresponding β-alkoxy alcohols using graphite oxide (GO) as the catalyst, under very mild reaction conditions is described. The method proceeds in good to excellent yields and in short reaction times at room temperature under metal-free conditions. 相似文献
222.
Coupling reactions of epoxide linked to a secondary oxygen group with Gilman reagents were examined. The regiochemical direction depended on whether there is TMS or MOM as a protective group of the secondary alcohol. anti-Epoxy alcohol 6 tended to react with Me2CuLi at the C4 position to generate 1,2-diol 22 as a major component. Epoxide 7 linked to a trimethylsilyloxy group displayed selective formation of 1,3-diol 18. On the other hand, the reactions of syn-epoxy alcohol 12 and the corresponding TMS ether 13 resulted in the selective formation of 1,2-diol 25. 相似文献
223.
The vast majority of scaffolds found in natural products are absent from the currently available compound collections for biological screening. At the same time, scaffolds derived from natural products may have a distinct advantage over non-natural cores in terms of providing compounds endowed with biological activities and should be used extensively in screening library design. We have developed a synthetic approach to merging a naturally occurring 1-azaadamantane core with a vicinal amino alcohol moiety that is also common in natural product chemical space. The synthesis features diastereoselective epoxidation of racemic chiral 2,6-diaryl-4-methylene 1-azaadamantanes with subsequent SN2-type epoxide opening in aqueous isopropanol. 相似文献
224.
Lucy Lee Maria Marti Villalba Robert B. Smith James Davis 《Electrochemistry communications》2009,11(8):1555-1558
The use of a novel epoxide label system as the basis of a new approach to monitoring thiol species relevant to animal welfare contexts is presented. The need for the development of on-site/field testing is demonstrated through the analysis of equine saliva before and after exercise and the implication of delays in the analysis process exposed. The system is selective for thiols and, in contrast to simpler labelling systems, could offer potential for speciation studies. 相似文献
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A highly effective and mild protocol for ring opening of epoxides with NH4SCN in the presence of catalytic amount of a multisite phase-transfer catalyst,α,α′,α″-N-hexakis(triethylammoniummethylene chloride)-melamine,is developed.A variety ofβ-hydroxy thiocyanates as important intermediates in agricultural and pharmaceutical chemistry were obtained in high yields with excellent regioselectivity and in short reaction times. 相似文献
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A new enantioselective synthetic route to the title compounds has been developed in a simple and practical way with high enantiopurity using commercially available starting material. 相似文献
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