Diastereoselective Synthesis of Chromeno[3,2- d ]isoxazoles via Brønsted Acid Catalyzed Tandem 1,6-Addition/Double Annulations of o -Hydroxyl Propargylic Alcohols

作者：Li Zhu, Pei-Xu Zhang, Zhao-Zhao Li, Xing-Lu Zhang, Hong-Yuan Cao, Yu‐Ning Gao, Ming Bian, Hui‐Yu Chen, Zhenjiang Liu · 发表于：Organic Letters · 年份：2022 · DOI：10.1021/acs.orglett.2c02830 · 被引用次数：18 · 研究领域：Synthesis of Indole Derivatives、Synthesis of Organic Compounds、Chemical Synthesis and Reactions

A Brønsted acid catalyzed tandem process to access densely functionalized chromeno[3,2- d ]isoxazoles with good to excellent yields and diastereoselectivities was disclosed. The procedure is proposed to involve a 1,6-conjugate addition/electrophilic addition/double annulations process of alkynyl o -quinone methides ( o -AQMs) in situ generated from o -hydroxyl propargylic alcohols with nitrones. Mild conditions, good functional group compatibility, easy scale-up of the reaction, and further product transformation demonstrated its potential application.