using chiral N-tert-butanesulfinyl imines as reaction intermediates, is described. The reaction of organolithium and Grignard reagents with hydroxy Weinreb amides, chemoselective N-tert-butanesulfinyl aldimine formation from keto aldehydes, decarboxylativeMannichreaction with β-keto acids of these aldimines, and organocatalyzed L-proline intramolecular Mannich cyclization are key steps of this methodology