Central-to-Axial Chirality Conversion Approach Designed on Organocatalytic Enantioselective Povarov Cycloadditions:
Giorgiana Denisa Bisag1, Daniel Pecorari1, Andrea Mazzanti1
1Department of Industrial Chemistry "Toso Montanari", Alma Mater Studiorum-University of Bologna, Viale Risorgimento 4, 40136, Bologna, Italy.
Abstract:
The first stereoselective synthesis of enantioenriched axially chiral indole-quinoline systems is presented. The strategy takes advantage of an organocatalytic enantioselective Povarov cycloaddition of 3-alkenylindoles and N-arylimines, followed by an oxidative central-to-axial chirality conversion process, allowing for access to previously unreported axially chiral indole-quinoline biaryls. The methodology is also implemented for the design and the preparation of challenging compounds exhibiting two stereogenic axes. DFT calculations shed light on the stereoselectivity of the central-to-axial chirality conversion, showing unconventional behavior.
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