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Parallel combinatorial synthesis in solution using immobilized reagents, catalysts, and scavengers has emerged as a powerful technique for the preparation of diverse libraries of compounds. This technique has only recently been applied to the synthesis of large-ring compounds. In this comprehensive review several strategies are presented and discussed, including Pd-catalyzed allylic alkylation, Stille-coupling, macrolactonization and macrolactamization using solid supported reagents and catalysts. In several cases site isolation has allowed operation of these macrocyclization reactions in concentrated solution (pseudo-dilution effect). 相似文献
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Advances in organic synthesis using polymer-supported reagents and scavengers under microwave irradiation 总被引:1,自引:0,他引:1
Bhattacharyya S 《Molecular diversity》2005,9(4):253-257
Summary Microwave-assisted and polymer-supported organic syntheses have emerged independently as versatile tools for rapid generation
of organic molecules. Chemists are increasingly looking for a combination of both techniques for efficient organic synthesis.
This review covers the recent literature on organic synthesis using microwave heating in conjunction with polymer-supported
reagents and scavengers. 相似文献
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A direct kinetic study is reported for the electrophilic amination of substituted phenylmagnesium bromides with N,N‐dimethyl O‐(mesitylenesulfonyl)hydroxylamine in THF. Rate data, Hammett relationship, and activation entropy are consistent with a SN2 displacement involving the attack of carbanions to sp3N in the amination reagent (AR). Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
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The Barbier type allylation of carbonyl compounds is a useful organic transformation as the resultant homoallylic alcohols are important building blocks for many biologically active molecules. Tin mediated Barbier allylation of different carbonyl compounds in room temperature ionic liquid, [BMIM][BF4] afforded the corresponding homoallylic alcohols in good to excellent yields. The ionic liquid was successfully recycled and reused in allylation reactions. 相似文献
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