Single Electron Transfer‐Induced Selective α‐Oxygenation of Glycine Derivatives.

Modification of amino acids is an important strategy in organic and bioorganic chemistry. In contrast to common side‐chain functionalization, backbone modification is much less explored. Especially glycine units seem to be attractive and versatile since a wide range of functionality can be potentially introduced. We report here oxidative modification of glycinates that are stable and enable further functionalization. Selective glycinate enolate oxidation by TEMPO or a FeCp2PF6/TEMPO reagent combination provides stable alkoxyamines in good to excellent yields. The methodology is expanded to glycine‐containing dipeptides demonstrating selective oxygenation at the glycine unit. The orthogonal reactivity potential of oxygenated glycines for transformation to other amino acid derivatives is explored. [ABSTRACT FROM AUTHOR]