使用环氧烯醇硅烷作为官能化氧烯丙基阳离子前体的分子间和分子内[4 + 3]环加成反应。

Inter- and intramolecular [4 + 3] cycloadditions using epoxy enol silanes as functionalized oxyallyl cation precursors.

作者信息

Chung Wing Ki, Lam Sze Kui, Lo Brian, Liu Lok Lok, Wong Wing-Tak, Chiu Pauline

机构信息

Department of Chemistry and the Open Laboratory of Chemical Biology of the Institute of Molecular Technology for Drug Discovery and Synthesis, The University of Hong Kong, Pokfulam Road, Hong Kong, PR China.

出版信息

J Am Chem Soc. 2009 Apr 8;131(13):4556-7. doi: 10.1021/ja807566t.

DOI:10.1021/ja807566t

PMID:19281161

Abstract

Using epoxy enol triethylsilanes as oxyallyl cation precursors, [4 + 3] cycloadditions with various dienes occur under catalysis by silyl triflates and acids in good yields. The intramolecular [4 + 3] cycloaddition proceeds under mild conditions and generate hydroxylated cycloadducts with high diastereoselectivity and yields. Enantiomerically pure epoxy enol silanes have been shown to give excellent yields of the optically pure cycloadduct bearing multiple stereocenters.

摘要

使用环氧烯醇三乙基硅烷作为烯丙基氧阳离子前体，在三氟甲磺酸硅酯和酸的催化下，与各种二烯发生[4 + 3]环加成反应，产率良好。分子内[4 + 3]环加成反应在温和条件下进行，生成具有高非对映选择性和产率的羟基化环加合物。已证明对映体纯的环氧烯醇硅烷能以优异的产率得到带有多个立体中心的光学纯环加合物。