Catalytic oxidation of 1,2-diaminobenzene by the dinuclear cobalt(II)-OBISDIEN dioxygen complex

Catalytic oxidation of 1,2-diaminobenzene by the dinuclear cobalt(II)-OBISD IEN dioxygen complex and its hydroxo derivatives was observed. The rate of reaction of 1,2-diaminobenzene-Co-OBISDIEN dioxygen complexes shows first o rder behavior and the specific rate constants for the active species presen t were determined as LCo2XO2, k = 2.32 x 10(-4) s(-1); LCo2(OH)XO2 k' = 1.2 0 x 10(-4) s(-1); and LCo2(OH)(2)XO2, k" = 1.10 x 10(-4) s(-1). The analysi s of the mass spectrum and C-13 NMR reveal 2,3-diaminophenazine as the only oxidation product. (C) 1999 Elsevier Science S.A. All rights reserved.