Bifunctional Brønsted Base Catalyzed Mannich Reaction of β-Alkoxy α-Keto Amides: Stereocontrolled Entry to Functionalized Amino Diols.

The potential of β-alkoxy α-keto amides as pronucleophiles in the enantioselective Mannich type reaction with p-nosyl imines is presented. The proper combination of β-alkoxy α-keto amides and a squaramide-based Brønsted base catalyst produced highly enantioenriched Mannich adducts, which may be transformed into functionalized amino diols.