γ-羟基-顺式烯烃的催化对映选择性碘环化反应

Catalytic enantioselective iodocyclization of gamma-hydroxy-cis-alkenes.

作者信息

Kang Sung Ho, Lee Sung Bae, Park Chul Min

机构信息

Center for Molecular Design and Synthesis, Department of Chemistry, School of Molecular Science (BK21), Korea Advanced Institute of Science and Technology, Daejeon 305-701, Korea.

出版信息

J Am Chem Soc. 2003 Dec 24;125(51):15748-9. doi: 10.1021/ja0369921.

DOI:10.1021/ja0369921

PMID:14677957

Abstract

Enantioselective iodocyclization of gamma-hydroxy-cis-alkenes has been achieved using I2 in the presence of an unprecedented catalyst system generated from (R,R)-t-Bu-salen-Co(II) complex and NCS to produce 2-monosubstituted tetrahydrofurans up to 90% ee. While NCS turned out to be the essential additive, neither (R,R)-salen-Co(II) nor (R,R)-salen-Co(III) by itself is likely to be the active species responsible for the asymmetric intramolecular iodoetherification.

摘要

在由（R，R）-叔丁基-萨伦-钴（II）配合物和NCS生成的前所未有的催化剂体系存在下，使用I₂实现了γ-羟基-顺式烯烃的对映选择性碘环化反应，生成了对映体过量高达90%的2-单取代四氢呋喃。虽然结果表明NCS是必不可少的添加剂，但单独的（R，R）-萨伦-钴（II）或（R，R）-萨伦-钴（III）都不太可能是负责不对称分子内碘醚化反应的活性物种。