Highly Regio‐, Diastereo‐, and Enantioselective Assembly of Azepino[2,3‐<i>b</i>]indoles <i>via</i><scp>Palladium‐Catalyzed</scp> [4 + 3] Cycloaddition<sup>†</sup>
Wu‐Lin Yang, Zesheng Huang, Yang‐Zi Liu, Xingxin Yu, Wei‐Ping Deng
Abstract
Summary of main observation and conclusion A palladium‐catalyzed asymmetric [4 + 3] cycloaddition of trimethylenemethanes and indoline‐derived aza‐dienes has been developed. The potential [3 + 2] side pathway was completely suppressed in the process. This protocol provides an efficient access to azepino[2,3‐ b ]indoles bearing two vicinal stereocenters in generally excellent diastereo‐ and enantioselectivities (up to > 20 : 1 dr, 99% ee).
Topics & Concepts
ChemistryStereocenterEnantioselective synthesisPalladiumCycloadditionIndolineVicinalCatalysisCombinatorial chemistryStereochemistryMedicinal chemistryOrganic chemistryCatalytic C–H Functionalization MethodsAsymmetric Synthesis and CatalysisCyclopropane Reaction Mechanisms