Functional Group Migration-Driven Quaternary Carbon Editing via Intramolecular [4+2] Annulation
Yi-Xin Xing1,2, Bo-Xi Liu1,2, Feng Zhou1,2, Syed Anis Ali Shah1,2, Daopeng Sheng3,4, WeiDong Rao5, Shu-Su Shen6, Chen Zhu(朱晨)7,8*, Shun-Yi Wang(汪顺义)1,2*
1Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, China
2Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215123, China
3State Key Laboratory of Radiation Medicine and Protection, School for Radiological and Interdisciplinary Sciences (RAD-X), Soochow University, Suzhou, Jiangsu 215123, China
4Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, Soochow University, Suzhou, Jiangsu 215123, China
5Key Laboratory of Biomass-based Green Fuels and Chemicals, College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, China
6School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 215009, P. R. China
7School of Environmental Science and Engineering Frontiers Science Center for Transformative Molecules, Zhangjiang Institute for Advanced Study, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China
8Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China
Org. Lett.2026,28,10187-10193
Abstract: A photocatalytic tandem radical intramolecular[4+2] cyclization of unactivated cyanated alkenes for constructing functionalized benzo[1,6]naphthyridinones through the integration of radical cyano migration and hydrogen atom transfer (HAT) strategies is reported. This protocol uses mild reaction conditions, readily accessible and stable substrates, and a metal-free organic photocatalyst while enabling late-stage functionalization. The mechanistic study reveals that the intramolecular [4+2] cyclization mechanism involves radical addition to an unactivated alkene, followed by 1,4-cyano migration, 1,6-HAT, and a subsequent intramolecular 6-endo-trig radical cyclization process.
Article information: https://doi.org/10.1021/acs.orglett.6c02476
