Synthesis of chiral unsaturated aminolactones using Pd-catalyzed allylic amination

Stereoselective synthesis of (5R,6R)- and (5S,6S)-5-benzylamino-6-(tert-butyldimethylsilanyloxymethyl)-5,6-dihydropyran-2-ones starting from d-glucal and furanaldehyde, respectively, is described. The synthesis relies on a Sharpless asymmetric dihydroxylation, an Achmatowicz reaction, and a stereoselective Pd-catalyzed allylic amination as the key steps.

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(5S,6S)-5-Benzylamino-6-(tert-butyl-dimethylsilanyloxymethyl)-5,6-dihydro-pyran-2-oneC19H29NO3SEe >95%, de 100%[α]D20=-35.2 (c 1.0, CH3OH)Source of chirality: Sharpless dihydroxylation, intramolecular induction of asymmetryAbsolute configuration: (5S,6S)