Formation and [3,3]-sigmatropic rearrangement of O-allyl nitronic esters: a new route to gamma,delta-unsaturated nitro compounds.

O-Allyl nitronic esters that are obtained from tin(IV) catalyzed Diels-Alder reactions undergo thermal rearrangement to gamma,delta-unsaturated nitro compounds.

Asymmetric synthesis of (-)-nupharamine and (-)-(5S,8R,9S)-5-(3-furyl)-8-methyloctahydroindolizidine from beta-amino ketones and the intramolecular Mannich reaction.

The asymmetric synthesis of the 2,3,6-trisubstituted piperidine core of the antitumor Nuphar alkaloids was readily achieved by using the intramolecular Mannich reaction and a sulfinimine-derived beta-amino ketone.