Combining the catalytic enantioselective reaction of visible-light-generated radicals with a by-product utilization system. Issue 10 (1st September 2017)

• Record Type: Journal Article
• Authors: Huang, Xiaoqiang; Luo, Shipeng; Burghaus, Olaf; Webster, Richard D.; Harms, Klaus; Meggers, Eric
• Is Part Of: Chemical science. Volume 8:Issue 10(2017)
• Page Start: 7126
• Page End: 7131
• Publication Date: 2017-09-01
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/c7sc02621h
• Languages: English
• ISSNs: 2041-6520

Abstract

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. 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.