Organocatalytic and enantioselective [4+2] cyclization between hydroxymaleimides and ortho-hydroxyphenyl para-quinone methide-selective preparation of chiral hemiketals

Min Xiang; Chen-Yi Li; Xiang-Jia Song; Ying Zou; Zhi-Cheng Huang; Xia Li; Fang Tian; Li-Xin Wang

doi:10.1039/d0cc06777f

Organocatalytic and enantioselective [4+2] cyclization between hydroxymaleimides and ortho-hydroxyphenyl para-quinone methide-selective preparation of chiral hemiketals

Chem Commun (Camb). 2020 Nov 26;56(94):14825-14828. doi: 10.1039/d0cc06777f.

Authors

Min Xiang¹, Chen-Yi Li¹, Xiang-Jia Song¹, Ying Zou¹, Zhi-Cheng Huang¹, Xia Li¹, Fang Tian², Li-Xin Wang²

Affiliations

¹ Key Laboratory of Asymmetric Synthesis and Chirotechnology of Sichuan Province, Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041, China. wlxioc@cioc.ac.cn tnfg@sina.com and University of Chinese Academy of Sciences, Beijing 100049, China.
² Key Laboratory of Asymmetric Synthesis and Chirotechnology of Sichuan Province, Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041, China. wlxioc@cioc.ac.cn tnfg@sina.com.

PMID: 33155600
DOI: 10.1039/d0cc06777f

Abstract

A cinchona alkaloid squaramide promoted enantioselective [4+2] cyclization between hydroxymaleimides and ortho-hydroxyphenyl p-QMs has been disclosed, and a wide range of chiral hemiketals containing chromane and succinimide frameworks with two adjacent quaternary stereogenic centers have been prepared for the first time with excellent results (up to 99% yield, up to 99 : 1 dr, up to >99% ee) under mild conditions.