Highly reactive mu-carbido diiron tetraphenylporphine oxo-species: chemical generation and the oxidation ability

Авторы публикации: 
Zaitseva S.V., Tyulyaeva E.Y., Simonova O.R., Zdanovich S.A, Tyurin D.V., Koifman O.I.
Journal of Coordination Chemistry
Год публикации: 
V.71, № 16-18. -- P. 2993-3007

The multistep interaction of a mu-carbido diiron tetraphenylporphine complex and its imidazole derivative with tert-butylhydroperoxide (BuOOH)-Bu-t were investigated in benzene at 298 K by UV-visible, IR spectroscopy and electrochemical study. The kinetics of the step-wise processes were studied and their rate constants k were obtained. The reaction of both non-ligated [(FeTPP)-T-IV](2)C (1) and [ImFe(IV)TPP](2)C (2) with (BuOOH)-Bu-t led to high-oxidized species generation following the coordination of a peroxide molecule on the metal center (k(1) = 2.8 M(-1)s(-1)) and homolytic cleavage of O-O bond in attached (BuOOH)-Bu-t (k(2) = 3.1 s(-1) for 1, k(2) = 12.8 s(-1) for 2). [(FeTPP)-T-IV](2)C underwent one-electron ring oxidation to form a pi-cation radical (k(ox) = 3.9 s(-1)) detected by UV-visible and IR spectroscopy. Imidazole-derivative formed a powerful oxidizing species that is able to oxidize the organic peroxide employed. The oxidant-intermediate reacting rapidly when produced in solution was proposed to be double-oxidized species due to its high reactivity (k(red) = 2660 M(-1)s(-1)). The results of UV-visible, IR, ESI-MS study supported the final products with Fe = C = Fe unit.

Колкер Римма Семеновна