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Catalytic Stereoselective Borylative Transannular Reactions
Jana Sendra1,2, Ruben Manzano2, Efraim Reyes2
1Department Química Física i Inorgànica, University Rovira i Virgili, C/ Marcel⋅lí Domingo s/n, Spain.
Abstract:
Medium-sized carbocycles containing an α,β-unsaturated ketone moiety as Michael acceptor site and a ketone moiety as internal electrophilic site are ideal substrates to conduct Cu(I)-catalyzed conjugated borylation followed by electrophilic intramolecular trapping that results into a pioneer transannular borylative ring closing reaction. The relative configuration of three adjacent stereocenters is controlled, giving access to a single diastereoisomer for a wide range of substrates tested. Moreover, when a chiral ligand is incorporated, the reaction provides enantioenriched polycyclic products with up to 99 % ee.
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