Reactivity of the HO/B(OH)/HO system in the decomposition of 4-nitrophenyl esters of diethylphosphonic and diethylphosphoric acids

The kinetics of the decomposition of 4-nitrophenyl diethylphosphonate and 4-nitrophenyl diethyl phosphate by the HO/B(OH)/HO system with wide variation of the pH and the initial concentrations of HO and B(OH) (water, 25°C) was studied. Additions of boric acid either weakly accelerate the reaction or retard it, depending on the ratio of the initial concentrations of hydrogen peroxide and boric acid and on the nature of the substrate. The peroxoborate anions (HO)BOOH, (HO)B(OOH), and (HO)BOOB(OH) anions generated by this system do not affect the decomposition rate of the substrates. In both substrates linear relationships were found between the observed rate constants k and the concentrations of peroxide anion.