Sterically congested "roofed" 2-iminothioethers as new chiral ligands for palladium-catalyzed asymmetric allylic alkylation

The preparation of a new class of "roofed" aminothiol derivatives, from sterically congested, conformationally rigid chiral 2-thiazolidinones is described. The compounds function as efficient chiral ligands for the palladium-catalyzed asymmetric allylic alkylation of 1,3-diphenyl-2-propenyl acetate with dimethyl malonate in the presence of cesium carbonate as a base.