Construction of enantioenriched eight-membered lactones via Pd-catalyzed asymmetric(6+2)dipolar annulation  

作　　者：Bao-Cheng Wang Yi Wei Feng-Ya Xiong Bao-Le Qu Wen-Jing Xiao Liang-Qiu Lu 

机构地区：[1]Key Laboratory of Pesticide&Chemical Biology,Ministry of Education,College of Chemistry,Central China Normal University,Wuhan,430079,China [2]State Key Laboratory of Organometallic Chemistry,Shanghai Institute of Organic Chemistry,University of Chinese Academy of Sciences,Chinese Academy of Sciences,Shanghai,200032,China [3]School of Chemistry and Chemical Engineering,Henan Normal University,Xinxiang,453007,China [4]State Key Laboratory for Oxo Synthesis and Selective Oxidation,Lanzhou Institute of Chemical Physics(LICP),Chinese Academy of Sciences,Lanzhou,730000,China

出　　处：《Science China Chemistry》2022年第12期2437-2443,共7页中国科学（化学英文版）

基　　金：supported by the National Natural Science Foundation of China(21822103,21820102003,91956201);the Program of Introducing Talents of Discipline to Universities of China(111Program,B17019);the Natural Science Foundation of Hubei Province(2017AHB047);Hubei International Scientific and Technological Cooperation Base of Pesticide and Green Synthesis。

摘　　要：Concise synthesis of eight-membered lactones,a kind of medium-sized heterocycles widespread in many bioactive natural products,is highly significant.However,it still remains a challenge due to unfavorable entropic factor and transannular interaction.Herein,we disclose an enantioselective synthesis of eight-membered lactones through a Pd-catalyzed asymmetric(6+2)dipolar annulation of vinyl oxetanes andα-diazo ketones(20 examples,up to 93%yield and 95:5 er).This reaction features simple operation,mild conditions and good enantiocontrol,especially the challenging chiral all-carbon quaternary stereocenter.A newly developed chiral hybrid P,S ligand and the in-situ photo-generation of ketene dipolarophiles are crucial to this success.

关 键 词：asymmetric catalysis dipolar annulation eight-membered lactone KETENE palladium 

分 类 号：O621.251[理学—有机化学]