Hydroxylamine oxygen as nucleophile in palladium(0)- and palladium(II)-catalyzed allylic alkylation: A novel access to isoxazolidines

摘要

In search for novel heterocyclization processes, the intramolecular Pd-mediated allylic alkylation of homoallyl hydroxylamines is described. Depending on both the reaction conditions and the substrates, cis- or trans-3-substituted-5-vinyl isoxazolidines are preferentially obtained. The corresponding starting materials for the cyclization step are readily obtained through cross-metathesis of the easily accessible unsubstituted homoallyl hydroxylamines.