Asymmetric disulfonimide-catalyzed synthesis of δ-amino-β-ketoester derivatives by vinylogous Mukaiyama-Mannich reactions

An organocatalytic asymmetric synthesis of δ-amino-β-ketoester derivatives has been developed. A chiral disulfonimide (DSI) serves as a highly efficient precatalyst for a vinylogous Mukaiyama-Mannich reaction of readily available dioxinone-derived silyloxydienes with N-Boc-protected imines, delivering products in excellent yields and enantioselectivities. The synthetic utility of this reaction is illustrated in various transformations, including a new CC bond-forming reaction, which provide useful enantioenriched building blocks. The methodology is applied in a formal synthesis of (-)-lasubin.

Catalytic asymmetric Torgov cyclization: a concise total synthesis of (+)-estrone

An asymmetric Torgov cyclization, catalyzed by a novel, highly Brønsted acidic dinitro-substituted disulfonimide, is described. The reaction delivers the Torgov diene and various analogues with excellent yields and enantioselectivity. This method was applied in a very short synthesis of (+)-estrone.

Asymmetric allylation of sulfonyl imines catalyzed by in situ generated Cu(ii) complexes of chiral amino alcohol based Schiff bases

We have developed a catalytic route for enantioselective synthesis of homoallyl amines through Cu(ii)-Schiff base catalyzed allylation of aryl N-sulfonylimines.

A Lewis acid palladium(II)-catalyzed three-component synthesis of α-substituted amides

A Lewis acid palladium-catalyzed reaction of amides, aryl aldehydes, and arylboronic acids is described. This new method allows for a practical and general synthesis of α-substituted amides from simple, readily available building blocks.