Catalytic asymmetric and chemoselective aerobic oxidation: kinetic resolution of sec-alcohols

Optically active (nitroso)(salen)ruthenium(II) chloride (2) was found to be an efficient catalyst for aerobic oxidation of racemic secondary alcohols under irradiation with a halogen or fluorescent lamp, which proceeded with good enantiomer-differentiation (krel=11–20). Furthermore, no epoxidation was observed in the oxidation of racemic 4-phenyl-3-buten-2-ol.