KHSO4-Mediated Condensation Reactions of tert-Butanesulfinamide with Aldehydes. Preparation of tert-Butanesulfinyl Aldimines

Optically pure tert-butanesulfinyl aldimines 1 were prepared by direct condensation of chiral tert-butanesulfinamide 3 with aldehydes 2 in high yields in the presence of KHSO4. The main advantage of KHSO4 is that it is applicable to the condensation reactions of a variety of aldehydes, including electron deficient and electron rich (hetereo)aromatic aldehydes, as well as aliphatic aldehydes.