Huang, Xiaoqiang Webster, Richard D. Harms, Klaus Meggers, Eric Asymmetric Catalysis with Organic Azides and Diazo Compounds Initiated by Photoinduced Electron Transfer Electron-acceptor-substituted aryl azides and α-diazo carboxylic esters are used as substrates for visible-light-activated asymmetric α-amination and α-alkylation, respectively, of 2-acyl imidazoles catalyzed by a chiral-at-metal rhodium-based Lewis acid in combination with a photoredox sensitizer. This novel proton- and redox-neutral method provides yields of up to 99% and excellent enantioselectivities of up to >99% ee with broad functional group compatibility. Mechanistic investigations suggest that an intermediate rhodium enolate complex acts as a reductive quencher to initiate a radical process with the aryl azides and α-diazo carboxylic esters serving as precursors for nitrogen and carbon-centered radicals, respectively. This is the first report on using aryl azides and α-diazo carboxylic esters as substrates for asymmetric catalysis under photoredox conditions. These reagents have the advantage that molecular nitrogen is the leaving group and sole byproduct in this reaction. α- diazo carboxylic esters;Diazo Compounds Initiated;aryl azides;2- acyl imidazoles;chiral-at-metal rhodium-based Lewis acid;substrate;Photoinduced Electron Transfer Electron-acceptor-substituted aryl azides;photoredox 2016-08-31
    https://acs.figshare.com/articles/journal_contribution/Asymmetric_Catalysis_with_Organic_Azides_and_Diazo_Compounds_Initiated_by_Photoinduced_Electron_Transfer/3827571
10.1021/jacs.6b07692.s001