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Bromine radical as a visible-light-mediated polarity-reversal catalyst.

ABSTRACT: 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.

SUBMITTER: Wang H

PROVIDER: S-EPMC8243021 | biostudies-literature | 2021 Jun

REPOSITORIES: biostudies-literature

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Bromine radical as a visible-light-mediated polarity-reversal catalyst.

Wang Han H Liu Haiwang H Wang Mu M Huang Meirong M Shi Xiangcheng X Wang Tonglin T Cong Xu X Yan Jianming J Wu Jie J

iScience 20210605 6

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 t ...[more]

PMID: 34222843

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