Oxidative lactonization of C(sp^(3))–H bond in methyl aromatic alcohols enabled by proton-coupled electron transfer  

作　　者：Shanyi Chen Qihong Lai Chao Liu Hui Liu Mingqiang Huang Shunyou Cai 

机构地区：[1]Fujian Provincial Key Laboratory of Modern Analytical Science and Separation Technology,School of Chemistry,Chemical Engineering and Environment,Minnan Normal University,Zhangzhou 363000,China [2]Guangdong Provincial Key Laboratory of Chemical Genomics,School of Chemical Biology and Biotechnology,Shenzhen Graduate School,Peking University,Shenzhen 518055,China

出　　处：《Science China Chemistry》2022年第8期1526-1531,共6页中国科学（化学英文版）

基　　金：supported by the National Natural Science Foundation of China(21502086);the Natural Science Foundation of Fujian Province(2019J01744);the Key Project of Foundation of Fujian Province(2020J02044);the Natural Science Foundation of Zhangzhou City(ZZ2021J13)。

摘　　要：Direct functionalization of inert C(sp^(3))–H bonds in pharmaceutically significant compounds is very important in modern synthetic organic chemistry.In this article,we disclose a practical and efficient method for the oxidative lactonization of benzylic C(sp^(3))–H bonds enabled by the synergistic interactions of organic dye-type rose bengal,n-Bu_(4)N∙Br,O_(2) and Na_(2)HPO_(4) under visible light irradiation.This reaction does not require transition metal catalysts or strong oxidants.A range of structurally diverse phthalides has been synthesized with excellent selectivity and high functional group compatibility.The late-stage application of this reaction to the preparation of structurally complex phthalides demonstrates its synthetic utility.

关 键 词：photoredox catalyst metal free singlet oxygen bromine radical dehydrogenated lactonization 

分 类 号：O621.25[理学—有机化学]