Rapid catalytic oxygenation of hydrocarbons with perhalogenated ruthenium porphyrin complexes

Perhalogenated ruthenium porphyrins were found to be efficient catalysts for the oxygenation of hydrocarbons including secondary alkanes and benzene in the presence of 2,6-dichloropyridine N-oxide under mild conditions in aprotic media. Up to 15,000 turnovers and rates of 800 TO/min were obtained. A mechanism where Ru(III) - Ru(V) intermediates play an important role is proposed and discussed. The search for new methods for the catalytic oxygenation of hydrocarbons is one of the most important directions of modern chemistry [1]. Among the metalloporphyrin-mediated oxidations, ruthenium catalysts display remarkable activity for aerobic oxidations [2] (Fig. 1) and promising reactivity with N₂O [3].