Synlett 2006(4): 0657-0658  
DOI: 10.1055/s-2006-932492
SPOTLIGHT
© Georg Thieme Verlag Stuttgart · New York

New Achievements in TEMPO-Mediated Oxidations

Félix Calderón*
Departamento de Química Orgánica Biológica, Instituto de Química Orgánica General CSIC, C/ Juan de la Cierva 3, Madrid 28006, Spain
e-Mail: felix.calderon@iqog.csic.es;
Further Information

Publication History

Publication Date:
20 February 2006 (online)

Introduction

TEMPO (2,2,6,6-Tetramethyl-1-piperidinyloxy radical), as an oxidizing reagent, is the most representative member of the generally called nitroxyl radical oxidant family. They are characterized as weak oxidants that are stable, and soluble in both polar and apolar solvents. However, the radical can be oxidized to form the corresponding oxoammonium salt that is capable of oxidizing many organic functional groups. This oxidized species (Scheme 1) can be generated separately from the reaction mixture or, more interestingly, in situ, allowing a catalytic cycle.

Some reviews can be found in the literature, [1] but due to the increasing interest for this family of oxidants, new ­applications have been published. This Spotlight compiles novel oxidations catalyzed by TEMPO-oxoammonium salt from 2004 to present.