Pd-catalyzed stereoselective oxidation of methyl groups by inexpensive oxidants under mild conditions: A dual role for carboxylic anhydrides in catalytic C-H bond oxidation

Abstract

(Chemical Equation Presented) Unactivated CH3 groups in 2-oxazolines are oxidized by inexpensive oxidants, such as tert-butyl peroxyacetate and lauroyl peroxide, in the presence of a catalytic amount of Pd(OAc)2. Carboxylic anhydrides are essential for both the oxidation of the Pd-C bonds and regeneration of Pd(OAc)2. The use of [D 6]Ac2O as the solvent shows that the acetyl group incorporated into the product is from acetic anhydride rather than the oxidant (see scheme). © 2005 Wiley-VCH Verlag GmbH & Co. KGaA.