Double SO2 Insertion into 1,7-Diynes Leading to Functionalized Naphtho[1,2- c]thiophene 2,2-dioxides

Ai-Fang Wang; Wen-Juan Hao; Yi-Long Zhu; Guigen Li; Peng Zhou; Shu-Jiang Tu; Bo Jiang

doi:10.1021/acsomega.7b01789

Double SO₂ Insertion into 1,7-Diynes Leading to Functionalized Naphtho[1,2- c]thiophene 2,2-dioxides

ACS Omega. 2018 Feb 5;3(2):1482-1491. doi: 10.1021/acsomega.7b01789. eCollection 2018 Feb 28.

Authors

Ai-Fang Wang¹, Wen-Juan Hao¹, Yi-Long Zhu¹, Guigen Li^{2

3}, Peng Zhou², Shu-Jiang Tu¹, Bo Jiang¹

Affiliations

¹ School of Chemistry & Materials Science, Jiangsu Normal University, Xuzhou 221116, P. R. China.
² Institute of Chemistry & BioMedical Sciences, Nanjing University, Nanjing 210093, P. R. China.
³ Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409-1061, United States.

Abstract

A novel metal-free double SO₂ insertion/multicomponent bicyclization cascade of benzene-linked 1,7-diynes has been established by treatment with aryldiazonium tetrafluoroborates and DABCO-bis(sulfur dioxide) under redox-neutral conditions, providing a range of dual sulfone-containing naphtho[1,2-c]thiophene 2,2-dioxides with generally high stereoselectivity. The reaction pathway is proposed to proceed through the sequence of arylsulfonyl-radical-induced 6-exo-dig/5-endo-trig bicyclization, H-abstraction, and diazotization.