Abstract
It was found that triphenylphosphine was catalytically oxidized with molecular oxygen in the presence of π-C3H5Fe (CO) 3Br to form triphenylphosphine oxide. The oxidation reaction included not only the oxidation of the phosphine, but also the oxidative decomposition of π-C3H5Fe (CO) 3Br. In the former reaction, the phosphine was coordinated to the complex by the equimolecular substitution with the carbonyl. The resulting complex, π-C3H5Fe (CO) 2 (PPh3) Br, reacted with oxygen molecule to form the binuclear peroxo complex having oxygen molecule in the form of O22-, which oxidized the phosphine to its oxide. The latter reaction, on the other hand, comprised the activation of molecular oxygen to superoxide ion O2- on the complex. This type of oxygen was considered not to take part in the oxidation of the phosphine, and decompose its dioxygen complex. The oxidation of some other phosphorus compounds, such as P (n-butyl) 3, PCl3 and P (OPh) 3 were also tried using π-C3H5Fe (CO) 3Br as catalyst.
