Pd(II)-catalyzed primary-C(sp3)-H acyloxylation at room temperature.

With the aid of a novel S-methyl-S-2-pyridyl-sulfoximine (MPyS) directing group (DG), the unactivated primary β-C(sp(3))-H bond of MPyS-N-amides oxidizes at room temperature. The catalytic conditions are applicable to the diacetoxylation of primary β,β'-C(sp(3))-H bonds, and the carboxylic acid solvent is pivotal in the formation of the C-O bond. The MPyS-DG cleaves from the oxidation products and is recovered. This method provides convenient access to α,α'-disubstituted-β-hydroxycarboxylic acids.