期刊
TETRAHEDRON
卷 70, 期 27-28, 页码 4165-4180出版社
PERGAMON-ELSEVIER SCIENCE LTD
DOI: 10.1016/j.tet.2014.03.043
关键词
Kinetic resolution; Salen; Desymmetrization; Epoxides; Ring-opening
资金
- NIH [GM-43214]
- U.S. Department of Defense
- Pfizer
The (salen)Co catalyst (4a) can be prepared as a mixture of cyclic oligomers in a short, chromatographyfree synthesis from inexpensive, commercially available precursors. This catalyst displays remarkable enhancements in reactivity and enantioselectivity relative to monomeric and other multimeric (salen)Co catalysts in a wide variety of enantioselective epoxide ring-opening reactions. The application of catalyst 4a is illustrated in the kinetic resolution of terminal epoxides by nucleophilic ring-opening with water, phenols, and primary alcohols; the desymmetrization of meso epoxides by addition of water and carbamates; and the desymmetrization of oxetanes by intramolecular ring opening with alcohols and phenols. The favorable solubility properties of complex 4a under the catalytic conditions facilitated mechanistic studies, allowing elucidation of the basis for the beneficial effect of oligomerization. Finally, a catalyst selection guide is provided to delineate the specific advantages of oligomeric catalyst 4a relative to (salen)Co monomer 1 for each reaction class. (C) 2014 Elsevier Ltd. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据