An Exceptionally Stable Ti Superoxide Radical Ion: A Novel Heterogeneous Catalyst for the Direct Conversion of Aromatic Primary Amines to Nitro Compounds

A matrix-bound superoxide radical anion, generated by treating Ti(OR)4 (R=iPr, nBu) with H2O2, is a selective heterogeneous catalyst for the oxidation of anilines to the corresponding nitroarenes with 50 % aqueous H2O2 [Eq. (1)]. Yields of 82–98 % are obtained, even with anilines bearing electron-withdrawing substituents (R=NO2, COOH).