In Search of Radical Transformations from Metal Enolates. Direct Reactions of N-Acyl-1,3-oxazolidin-2-ones with TEMPO Catalyzed by Copper(II) Acetate

The direct reactions of a diverse range of N-acyl-1,3-oxazolidin-2-ones with TEMPO, catalyzed by copper(II) acetate and 4,7-dimethyl-1,10-phenanthroline without the need for any base, are herein described. These reactions afford the corresponding aminoxylated derivatives with high chemoselectivity and complete regioselectivity, achieving excellent yields under mild conditions. Further treatment of the resulting imides enables access to a variety of formally protected hydroxy compounds, which can be regarded as valuable synthetic intermediates. The efficient formal synthesis of isoproterenol highlights the potential of this methodology and sets the stage for further advancements in the catalytic chemistry of metal enolates.