Bromine radical as a visible-light-mediated polarity-reversal catalyst
Han Wang,
Haiwang Liu,
Mu Wang,
Meirong Huang,
Xiangcheng Shi,
Tonglin Wang,
Xu Cong,
Jianming Yan,
Jie Wu
Affiliations
Han Wang
Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Republic of Singapore
Haiwang Liu
Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Republic of Singapore
Mu Wang
Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Republic of Singapore
Meirong Huang
Shenzhen Bay Laboratory, State Key Laboratory of Chemical Oncogenomics, Peking University Shenzhen Graduate School, Shenzhen, P.R. China
Xiangcheng Shi
Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Republic of Singapore
Tonglin Wang
College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou, Gansu 730070, China
Xu Cong
Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Republic of Singapore
Jianming Yan
Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Republic of Singapore
Jie Wu
Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Republic of Singapore; National University of Singapore (Suzhou) Research Institute, 377 Lin Quan Street, Suzhou Industrial Park, Suzhou, Jiangsu, 215123, China; Corresponding author
Summary: Polarity-reversal catalysts enable otherwise sluggish or completely ineffective reactions which are characterized by unfavorable polar effects between radicals and substrates. We herein disclose that when irradiated by visible light, bromine can behave as a polarity-reversal catalyst. Hydroacylation of vinyl arenes, a three-component cascade transformation and deuteration of aldehydes were each achieved in a metal-free manner without initiators by using inexpensive N-bromosuccinimide as the precatalyst. Light is essential to generate and maintain the active bromine radical during the reaction process. Another key to success is that HBr can behave as an effective hydrogen donor to turn over the catalytic cycles.
