Key Laboratory of Medicinal for Natural Resource, Ministry of Education and Yunnan Province, School of Chemical Science and Technology, Yunnan University, Kunming 650091, China.
College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou 310014, P. R. China.
Org Lett. 2021 Nov 5;23(21):8267-8272. doi: 10.1021/acs.orglett.1c03008. Epub 2021 Oct 11.
A metal-free dual C(sp)-H bond functionalization of saturated cyclic ethers via photooxidative singlet oxygen-mediated ring opening and ring closing has been developed, providing a method for generating hydrobenzofurans/pyrans/dioxins. Mechanistic studies have confirmed that ring-opening intermediates were effectively generated by singlet oxygen-mediated C(sp)-H activation and efficiently reacted with aldehydes and activated methylene compounds to form a wide array of products with high diastereoselectivities (up to >95:5 dr). This study is a rare example of α,β-dual C(sp)-H bond functionalization of ethers.
通过光氧化单重态氧介导的开环和闭环反应，开发了一种无金属的饱和环状醚的双 C(sp)-H 键官能化方法，为生成氢化苯并呋喃/吡喃/二氧杂环己烷提供了一种方法。机理研究证实，开环中间体是通过单重态氧介导的 C(sp)-H 活化有效生成的，并与醛和活性亚甲基化合物高效反应，形成具有高非对映选择性（高达>95:5 dr）的广泛的产物。该研究是醚的 α,β-双 C(sp)-H 键官能化的罕见实例。
