TEMPO-Regulated Regio-and Stereoselective Cross-Dihalogenation with Dual Electrophilic X^(+) Reagents  

作　　者：Yi Kong Tongxiang Cao Shifa Zhu 

机构地区：[1]Key Laboratory of Functional Molecular Engineering of Guangdong Province,School of Chemistry and Chemical Engineering,South China University of Technology,Guangzhou,Guangdong,510640 China

出　　处：《Chinese Journal of Chemistry》2021年第11期3004-3010,共7页中国化学（英文版）

基　　金：financial support from the NSFC(Nos.21871096,22071062,22001077);the Ministry of Science and Technology of the People’s Republic of China(No.2016YFA0602900);the Guangdong Science and Technology Department(Nos.2018B030308007,2021A1515012331);the China Postdoctoral Science Foundation(Nos.2018M643062,2019T120723).

摘　　要：A TEMPO catalyzed cross-dihalogenation reaction was established via redox-regulation of the otherwise complex system of dual electrophilic X+reagents.Formally,the ICl,BrCl,I_(2) and Br_(2) were generated in-situ,which enabled high regio-or stereoselective access to a myriad of iodochlorination,bromochlorination and homo-dihalogenation products with a wide spectrum of functionalities.With its mild conditions and operational simplicity,this method could enable wide applications in organic synthesis,which was exemplified by divergent synthesis of two pharmaceuticals.Detailed mechanistic investigations via radical clock reaction,pinacol ring expansion and Hammett experiments were conducted,which confirmed the intermediacy of halonium ion.In addition,a dynamic catalytic model based on the versatile catalytic role of TEMPO was proposed to explain the selective outcomes.

关 键 词：HALOGENATION ORGANOCATALYSIS Electrophilic addition REDOX-REGULATION ALKYNES 

分 类 号：O62[理学—有机化学]