Substituent effect on rates of one-electron oxidation of airlines by borate radical – a flash photolysis study

Abstract

The borate radical B(OH)₃O^- generated during the flash photolysis of an aqueous solution of sodium metaborate and potassium peroxydisulphate, at <em>p</em>H 11.5 oxidises aniline and <em>p-</em>substituted anilines. The best Hammett correlation is obtained with σ<img src='http://www.niscair.res.in/jinfo/equation126.gif' border=0> constants with a negative <em>ρ </em>value (<em>ρ </em>= - 0.87) indicating the electrophilic nature of the reaction. The products formed as well as the relationship between rate constants for substituted anilines and their oxidation peak potential point to an electron transfer mechanism.