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3721769 
Journal Article 
MANGANESE(II)-CATALYSED PERIODATE OXIDATION OF 2-AMINO-m-XYLENE. A KINETIC-MECHANISTIC STUDY 
Kaushik, RD; Malik, R; Kumar, T; Singh, P 
2012 
1 
Oxidation Communications
ISSN: 0209-4541 
35 
2 
316-326 
WOS:000306253000006 
Results of kinetics of the Mn(II)-catalysed periodate oxidation of 2-amino-m-xylene (AMX) in acetone water medium under pseudo-first order conditions, [IO4-] << [AMX], are in agreement with the rate law: d[C]/dt = kK(3)K(4)K(w)[Mn(II)] [S](0) [IO4-][H+]/(K2Kw + (K-w + KbK2)[H+] + K-b [H+](2)) where kK(3)K(4) is the empirical composite rate constant; Kw ionic product of water; K-2 - acid dissociation constant of H4IO6-, and K-b - base dissociation constant of AMX. [S]c, represents the concentration of AMX which has been taken in excess. In agreement with the rate law the 1/k(obs) versus [W] profile passes through the minimum. Rate of reaction decreases on increasing the ionic strength and decreasing the dielectric constant of the medium. Free radical scavengers do not affect the reaction rate. The main reaction product is 2,6-dimethyl-p-benzoquinone. The values of thermodynamic parameters are: E-a = 2.46 kcal mol(-1), A = 6.1 x 10(6) dm(3) mol(-1) s(-1); Delta S* = -29.6 cal mol(-1) K-1, Delta G* = 11.2 kcal mol(-1) and Delta H* = 1.84 kcal mol(-1). 
kinetics; Mn(II)-catalysed; periodate oxidation; 2-amino-m-xylene; 2,6-dimethyl-p-benzoquinone