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Combining the catalytic enantioselective reaction of visible-light-generated radicals with a by-product utilization system.

ABSTRACT: We report an unusual reaction design in which a chiral bis-cyclometalated rhodium(iii) complex enables the stereocontrolled chemistry of photo-generated carbon-centered radicals and at the same time catalyzes an enantioselective sulfonyl radical addition to an alkene. Specifically, employing inexpensive and readily available Hantzsch esters as the photoredox mediator, Rh-coordinated prochiral radicals generated by a selective photoinduced single electron reduction are trapped by allyl sulfones in a highly stereocontrolled fashion, providing radical allylation products with up to 97% ee. The hereby formed fragmented sulfonyl radicals are utilized via an enantioselective radical addition to form chiral sulfones, which minimizes waste generation.

SUBMITTER: Huang X

PROVIDER: S-EPMC5637358 | biostudies-literature | 2017 Oct

REPOSITORIES: biostudies-literature

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Combining the catalytic enantioselective reaction of visible-light-generated radicals with a by-product utilization system.

Huang Xiaoqiang X Luo Shipeng S Burghaus Olaf O Webster Richard D RD Harms Klaus K Meggers Eric E

Chemical science 20170901 10

We report an unusual reaction design in which a chiral bis-cyclometalated rhodium(iii) complex enables the stereocontrolled chemistry of photo-generated carbon-centered radicals and at the same time catalyzes an enantioselective sulfonyl radical addition to an alkene. Specifically, employing inexpensive and readily available Hantzsch esters as the photoredox mediator, Rh-coordinated prochiral radicals generated by a selective photoinduced single electron reduction are trapped by allyl sulfones i ...[more]

PMID: 29147543

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