路易斯酸催化环丁烯酮的不对称[4+2]环加成反应以合成α,β-不饱和δ-内酯。

Lewis acid catalyzed asymmetric [4+2] cycloaddition of cyclobutenones to synthesize α,β-unsaturated δ-lactones.

作者信息

Yao Qian, Yu Han, Zhang Hang, Dong Shunxi, Chang Fenzhen, Lin Lili, Liu Xiaohua, Feng Xiaoming

机构信息

Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China.

出版信息

Chem Commun (Camb). 2018 Mar 29;54(27):3375-3378. doi: 10.1039/C8CC01040D.

DOI:10.1039/C8CC01040D

PMID:29547225

Abstract

Here we report an efficient asymmetric [4+2] cycloaddition of β,γ-unsaturated α-ketoesters with cyclobutenones. The corresponding products were obtained in good yields (up to 92%) with excellent enantioselectivities (up to 98% ee) and diastereoselectivities (up to >19/1 dr). Moreover, based on the control experiments and previous reports, a possible catalytic cycle was proposed.

摘要

在此，我们报道了β,γ-不饱和α-酮酯与环丁烯酮的高效不对称[4+2]环加成反应。相应产物以良好的产率（高达92%）、优异的对映选择性（高达98% ee）和非对映选择性（高达>19/1 dr）得到。此外，基于对照实验和先前的报道，提出了一个可能的催化循环。