A mechanistic investigation of bromoperoxidases mimicking systems. Evidence of a hypobromite-like vanadium intermediate from experimental data and ab initio calculations

A two-phase (H2O-CHCl3 or H2O-CH2Cl2) system in which NH4VO3, KBr and H2O2 are dissolved in the aqueous phase and the substrate, e.g., an aromatic compound or an olefin, in the organic one, has been shown to mimic the chemistry of bromoperoxidases. These enzymes catalyze the bromination of organic compounds. When the substrate is styrene or substituted stilbenes, both dibromoderivatives and halohydrins are formed. This is taken as evidence for the formation of a hypobromite-like vanadium complex. Ab initio calculations confirm the plausibility of the involvement of such a complex.