Synthesis of sulfur-containing benzo[ b]pyrrolo[2,1- c][1,4]oxazine-3,9-diones: blue light promoted radical cyclization process

Feng Pan; Haohu Li; Xiaohua Wang; Liwen Luo; Yanfei Lin; Qingkai Yu; Wenlin Xie; Lianpeng Zhang

doi:10.1039/d3ra02247a

Synthesis of sulfur-containing benzo[ b]pyrrolo[2,1- c][1,4]oxazine-3,9-diones: blue light promoted radical cyclization process

RSC Adv. 2023 May 15;13(20):13911-13918. doi: 10.1039/d3ra02247a. eCollection 2023 May 2.

Authors

Feng Pan^{1

2}, Haohu Li¹, Xiaohua Wang³, Liwen Luo¹, Yanfei Lin⁴, Qingkai Yu¹, Wenlin Xie², Lianpeng Zhang¹

Affiliations

¹ Yunnan Provincial Key Laboratory of Wood Adhesives and Glued Products, Southwest Forestry University Kunming 650224 Yunnan China lpz@zju.edu.cn.
² School of Chemistry and Chemical Engineering, Hunan University of Science and Technology Xiangtan 411201 Hunan China xwl2000zsu@163.com.
³ Tongji Zhejiang College Jiaxing 314051 China.
⁴ College of Biological, Chemical Sciences and Engineering, Jiaxing University Jiaxing 314001 Zhejiang China 11219008@zju.edu.cn.

Abstract

The selective and controllable construction of spio-tricyclic skeletons through visible light promoted radical cyclization still remains challenging. Herein, a general and convenient protocol for the blue light-promoted radical-mediated cascade spiro-cyclization/Michael addition of N-arylpropiolamides with thiophenols under metal-free conditions was developed. In this protocol, commercially available hydrochloric acid was employed as the cheap promoter and air as the sustainable oxidant. In addition, many functional groups tolerate the reaction conditions and produce a series of sulfur-containing benzo[b]pyrrolo[2,1-c][1,4]oxazine-3,9-diones.