Dioxygen complexes of ruthenium as homogeneous catalysts for the oxidation of triphenylphosphine

The complexes Ru(NCS)(CO)(NO)(PPh3)2(I) and Ru(O2)(NCS)(NO)(PPh3)2(II) have been shown to be efficient catalysts for the homogeneous oxidation of PPh3 to OPPh3. In xylene solution rate α[catalyst] and rate–1α[PPh3]–1. The rate depends on p(O2) for (I) but not for (II). A mechanism is suggested which accommodates these facts.