Transition-Metal-Catalyzed Ring Expansion of Diazocarbonylated Cyclic N-Hydroxylamines: A New Approach to Cyclic Ketonitrones.

Novel C-ethoxycarbonyl cyclic ketonitrones are synthesized from the Ag- or Cu-catalyzed ring expansion of $\beta$-diazo cyclic hydroxylamines. The latter are themselves easily obtained by the addn. of lithiated Et diazoacetate onto cyclic nitrones. The regioselective metal-catalyzed rearrangement of $\beta$-diazo cyclic hydroxylamines proved highly efficient and resulted in a synthetically useful ring expansion to produce 6- or 7-membered ring functionalized nitrones. The outcome of the two steps, i.e. nucleophilic addn. of $\alpha$-diazoesters to nitrones and ring expansion, is a formal nitrone homologation. [on SciFinder(R)]

Références

Titre
Transition-Metal-Catalyzed Ring Expansion of Diazocarbonylated Cyclic N-Hydroxylamines: A New Approach to Cyclic Ketonitrones.
Type de publication
Article de revue
Année de publication
2014
Revue
Org. Lett.
Volume
16
Pagination
4484–4487
ISSN
1523-7052
Soumis le 12 avril 2018