ON THE STRUCTURE AND REACTIVITY OF PEROXOTRANSITION-METAL COMPLEXES

The electronic structures of an early and a late eta-2-peroxotransition-metal complex have been investigated in an attempt to account for the similarities in the M-O and O-O bond lengths and the differences in reactivity in spite of the structural similarities around the metal peroxo group. Peroxotitanium(IV) 2,6-pyridinedicarboxylate is used as a model for an early eta-2-peroxotransition-metal complex while the late eta-2-peroxotransition-metal complex is modelled by peroxonickel(II) bis (t-butylisocyanate). The eta-2-peroxotitanium complex is most stable in the 1A1 state and the eta-2-peroxonickel complex in the B-3(2) state. The bonding between the metal atom and the peroxo fragments is analyzed both in terms of the frontier orbitals and orbital population analysis. The reactivity of the two complexes with organic substrates is briefly discussed.