An "end-on" chromium(III)-superoxo complex: crystallographic and spectroscopic characterization and reactivity in C-H bond activation of hydrocarbons.

Metal-superoxo intermediates have been invoked as reactive species in C-H bond cleavage of substrates by oxygenase enzymes. In this work, we have shown the first structurally characterized end-on chromium(III)-superoxo complex, [Cr(III)(14-TMC)(O(2))(Cl)](+), which was synthesized by reacting [Cr(II)(14-TMC)(Cl)](+) with O(2). The Cr(III)-superoxo intermediate has shown reactivities in C-H cleavage of alkylaromatics via a H-atom abstraction mechanism.