Catalytic Asymmetric [3+3] Cycloaddition of Activated Isocyanides with Azomethine Imines

Abstract

AbstractCatalytic asymmetric 1,3-dipolar cycloaddition reactions of activated isocyanides with various 2π dipolarophiles have been intensively studied, affording a wide range of enantioenriched five-membered N-heterocycles. In sharp contrast, the catalytic enantioselective higher-order cycloaddition of activated isocyanides has not been achieved yet. We present here our recent work on the development of an unprecedented silver-catalyzed highly diastereo- and enantioselective [3+3] cycloaddition of activated isocyanides with azomethine imines. This method features high efficiency, good to excellent stereocontrol, wide substrate scope, as well as operational simplicity. It is also noteworthy that the same catalytic system was proved to be suitable for not only the late-stage functionalization of complex bioactive molecules but also the kinetic resolution of racemic azomethine imines.1 Introduction2 Results and Discussion3 Summary and Outlook