Asymmetric synthesis of substituted tropinones using the intramolecular mannich cyclization reaction and acyclic N-sulfinyl beta-amino ketone ketals.

Sulfinimine-derived, enantiopure N-sulfinyl beta-amino ketone ketals on hydrolysis give dehydropyrrolidine ketones that on treatment with (Boc)(2)O/DMAP afford substituted tropinones in good yield.