Structural modeling of iron halogenases: synthesis and reactivity of halide-iron(iv)-oxo compounds

Abstract

A structural synthetic model of the iron(IV)-oxo-halide active species of non-heme iron dependent halogenases is reported. Compounds with general formula [Fe^IV(O)(X)(Pytacn)]⁺ (1-X, X = Cl, Br) have been prepared and characterized spectroscopically and chemically with regard to their oxidizing ability. 1-X performs hydrogen-atom abstraction of C–H bonds at reaction rates 2–3 times faster than the corresponding solvato dicationic species, thus modelling the first step in C–H functionalization taking place in natural halogenation.