Epoxidation of Olefins with a Silica-Supported Peracid
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- 作者：Rossella Mello ; Ana Alcalde-Aragon茅s ; Mar铆a Elena Gonz谩lez N煤帽ez ; Gregorio Asensio
- 刊名：The Journal of Organic Chemistry
- 出版年：2012
- 出版时间：August 3, 2012
- 年：2012
- 卷：77
- 期：15
- 页码：6409-6413
- 全文大小：265K
- 年卷期：v.77,no.15(August 3, 2012)
- ISSN：1520-6904
文摘
Anhydrous [2-percarboxyethyl] functionalized silica (2a) is an advantageous oxidant for performing the epoxidation of olefins 1. Epoxides 3 do not undergo the ring-opening reactions catalyzed by the acidic silica surface, except for particularly activated cases such as styrene oxide. The hydrophilic and acidic character of the silica surface does not interfere with the directing effects exerted by allylic H-bond acceptor substituents. The alkenes 1 carrying hydroxyl groups react with silica-supported peracid 2a faster than unsubstituted alkenes, thus reversing the trend known for reactions with soluble peracids. These results are attributed to the H-bond interactions of substrate 1 with the silanol and carboxylic acid groups bonded to the silica surface.