Asymmetric Synthesis of d-Proline, d-Pipecolic Acid, (2R,3S,4R)-3,4-Dihydroxyproline, and 1,4-Dideoxy-1,4-imino-d-talitol from a Common Precursor

Methodology involving stereoselective aza-Michael addition and ring-closing metathesis as key steps has been developed for the preparation of (2 R )-pipecolic acid, (2 R )-proline, (2 R ,3 S ,4 R )-3,4-dihydroxyproline, and the known glycosidase inhibiting azasugar 1,4-dideoxy-1,4-imino- d -talitol from a common starting material namely ( R )-cyclohexylideneglyceraldehyde in good overall yields.