Mechanisms of oxidation of rosaniline hydrochloride by potassium bromate in aqueous perchloric acid medium - A kinetic approach

Abstract

Bromate oxidizes the methyl group of rosaniline hydrochloride to an aldehyde group in aqueous HClO₄ medium. At n = 0.50M, NaClO₄ the oxidation was found to be first-order in [rosaniline] and zero-order in [bromate]. The stoichiometry of reaction determined by spectrophotometric titration was found to be 2 moles of bromate to 5 moles of [rosaniline]. The bromate reaction followed both a first-order acid-dependent and an acid-independent pathway, suggesting that both HBrO₃ and BrO^-₃ are principal oxidizing species. The reaction conforms to the rate law:

-d[ROS] = (a + b [H+]) [ROS]
 dt
 The result of this study indicate that the reaction probably occur by the inner-sphere mechanisms.