Synthesis of medium-sized benzo[b]azocines and benzo[b]azonines by photoinduced 8-/9-endo sulfonyl-cyclization  

作　　者：Kai Sun Dongyang Zhao Quanxin Li Shaofei Ni Guangfan Zheng Qian Zhang 

机构地区：[1]College of Chemistry and Chemical Engineering,Yantai University,Yantai,264005,China [2]College Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Materials of Guangdong Province,Shantou University,Shantou,515063,China [3]Department of Chemistry,Northeast Normal University,Changchun,130024,China

出　　处：《Science China Chemistry》2023年第8期2309-2316,共8页中国科学（化学英文版）

基　　金：supported by the National Natural Science Foundation of China(21801007);Qingchuang Technology Support Program of University in Shandong Province(2021KJ066);funding from the STU Scientific Research Foundation for Talents(NTF20022)。

摘　　要：An efficient photochemical radical sulfonyl cyclization of designed dienes to medium-sized benzo[b]azocines and benzo[b]azonines was developed.This chemoselective method provides new highly functionalized eight-and nine-membered N-heterocycles.Radical inhibition experiments,light on/off experiments,and apparent quantum efficiency calculations were used to clarify the radical mechanism.Density functional theory calculations enabled rationalization of the rate-determining step and observed chemoselectivity.Large-scale synthesis and derivatizations via epoxidation and convenient N-Ts deprotection showed the potential utility of this strategy.This photochemical method for synthesizing sulfonylbenzo[b]azocines and sulfonylbenzo[b]azonines with insertion of sulfur dioxide provides new sustainable routes for the synthesis of valuable medium-sized Nheterocycles.

关 键 词：photocatalysis medium-sized N-heterocycles RADICAL cascade cyclization DFT study 

分 类 号：O626[理学—有机化学]