Copper-Catalyzed Asymmetric Functionalization of Vinyl Radicals for the Access to Vinylarene Atropisomers.

Abstract

A novel asymmetric radical strategy for the straightforward synthesis of atropisomerically chiral vinyl arenes has been established herein, proceeding through copper-catalyzed atroposelective cyanation/azidation of aryl-substituted vinyl radicals. Critical to the success of the radical relay process is the atroposelective capture of the highly reactive vinyl radicals with chiral L*Cu(II) cyanide or azide species. Moreover, these axially chiral vinylarene products can be easily transformed into atropisomerically enriched amides and amines, enantiomerically enriched benzyl nitriles via an axis-to-center chirality transfer process, and an atropisomerically pure organocatalyst for the chemo-, diastereo-, and enantioselective (4 + 2) cyclization reaction.