Stereoselective Synthesis of Hexahydroimidazo[1,2-<i>a</i>]quinolines via S<sub>N</sub>2-Type Ring-Opening Hydroarylation–Hydroamination Cascade Cyclization of Activated Aziridines with <i>N</i>-Propargylanilines
Sajan Pradhan, Navya Chauhan, Chandan Kumar Shahi, Aditya Bhattacharyya, Manas K. Ghorai
Abstract
A novel synthetic approach for the construction of 1,2,3,3a,4,5-hexahydroimidazo[1,2-a]quinolines in good yields (up to 75%) with excellent stereoselectivity (dr up to 94:6, ee up to >99%) under one-pot domino ring-opening cyclization (DROC) conditions has been developed. The DROC protocol proceeds through a Lewis acid catalyzed SN2-type ring-opening of activated aziridines with N-propargylanilines followed by intramolecular cyclization comprising concomitant hydroarylation and hydroamination steps in a domino fashion.
Topics & Concepts
HydroaminationChemistryStereoselectivityRing (chemistry)DominoIntramolecular forceCatalysisCascade reactionStereochemistryCombinatorial chemistryAziridineLewis acids and basesAminationCascadeMedicinal chemistryOrganic chemistryChromatographySynthesis and Catalytic ReactionsCatalytic C–H Functionalization MethodsAsymmetric Synthesis and Catalysis