Reactions of phosphate radicals with monosubstituted benzenes. A mechanistic investigation.

J. A. ROSSO; P. CAREGNATO; V. MORA; M. C. GONZALEZ; D. O. MÁRTIRE

HELVETICA CHIMICA ACTA

WILEY-V C H VERLAG GMBH

Año: 2003 p. 2509 - 2524

0018-019X

The kinetics and reaction mechanism of phosphate radicals with substituted benzenes, PhX (XOH, Me, H, Cl, MeO, and CHO), were studied by flash photolysis and continuous irradiation of aqueous solutions containing potassium peroxodiphosphate (K4[(PO3)2O2]). The rate constants for the reactions of phosphate radicals with the aromatic contaminants PhX were measured and the reaction intermediates and products detected.Acorrelation between the logarithm of the rate constant for every substrate with H2PO4OH, Me, H, Cl, MeO, and CHO), were studied by flash photolysis and continuous irradiation of aqueous solutions containing potassium peroxodiphosphate (K4[(PO3)2O2]). The rate constants for the reactions of phosphate radicals with the aromatic contaminants PhX were measured and the reaction intermediates and products detected.Acorrelation between the logarithm of the rate constant for every substrate with H2PO44[(PO3)2O2]). The rate constants for the reactions of phosphate radicals with the aromatic contaminants PhX were measured and the reaction intermediates and products detected.Acorrelation between the logarithm of the rate constant for every substrate with H2PO42PO4 ., HPO4, HPO4 ., and PO4, and PO44 .2 and the logarithm of the dissociation constant Ka for H3PO4, H2PO4 , and HPO2 4 was found. A general mechanism is proposed (Scheme 1), which accounts for the experimental results.2 and the logarithm of the dissociation constant Ka for H3PO4, H2PO4 , and HPO2 4 was found. A general mechanism is proposed (Scheme 1), which accounts for the experimental results.Scheme 1), which accounts for the experimental results.