Electrochemical oxidation of various para-and meta-substituted benzylamines in different mole fractions of 2-methylpropan-2-ol in water has been investigated in the presence of 0.1 M sulfuric acid as supporting electrolyte. The oxidation potential data of benzylamines correlates well with Hammett's substituent constants affording negative reaction constants (−1.112 < ρ > −1.529). The correlation of the oxidation potential values with macroscopic solvent parameters is nonlinear, suggesting the operation of both specific and nonspecific solvent-solvent-solute interaction mechanisms. Correlation of the experimental data with Kamlet-Taft solvatochromic parameters is excellent (100r 2 > 98%) and the results reveal that the reactivity is influenced by the preferential solvational effects.

The kinetics of oxidation of 11 para-and meta-substituted benzylamines by imidazolium fluorochromate (IFC) in different organic solvent media has been investigated in the presence of p-toluenesulfonic acid (TsOH). The reaction was run under pseudo-first-order conditions. The rate of the reaction was found to be first order in IFC and found to increase with increase in [TsOH]. Solution IR studies in combination with kinetic measurements were used to get a better insight into the mechanism of the oxidation process. The product analysis was carried out using GC-MS. Various thermodynamic parameters for the oxidation have been reported and discussed along with the validity of the isokinetic relationship. The specific rate of oxidizing species benzylamines reaction (k 2 ) correlates with Hammett's substituent constants affording positive reaction constants. The rate data failed to correlate with macroscopic solvent parameters, such as ε r and E N T , while showing satisfactory correlation with Kamlet-Taft's solvatochromic parameters (α, β, and π *) which suggests that the specific solute-solvent interactions play a major role in governing the reactivity, and the observed solvent effects have been explained on the basis of solute-solvent complexation. C 2007 Wiley Periodicals, Inc. Int J Chem Kinet

Electrochemical oxidation of nine para-and meta-substituted benzylamines in varying mole fractions of acetic acid in water has been investigated in the presence of 0⋅1 M sulphuric acid as supporting electrolyte. The oxidation potentials correlate well with Hammett's substituent constants affording negative reaction constants. The correlation of potential values with macroscopic solvent parameters is non-linear suggesting that the operation of both specific and non-specific solvent-solvent-solute interaction mechanisms. Multiple correlation analysis of the experimental data with Kamlet-Taft solvatochromic parameters is employed.

Imidazolium fluorochromate (IFC) oxidation of 11 meta-and para-substituted benzylamines, in varying mole fractions of benzene/2-methylpropan-2-ol binary mixtures, is first order in IFC and acid and zero order in substrate. The Hammett correlation yielded a U-shaped curve, indicating a change in the relative importance of bond formation and bond fission in the transition state. The rate data failed to correlate with macroscopic solvent parameters such as ε r and E N T . The correlation of k obs with Kamlet-Taft solvatochromic parameters suggests that H-bonding between the reacting species and the solvent plays a major role in governing the reactivity. C 2010 Wiley Periodicals, Inc. Int J Chem Kinet 42: [159][160][161][162][163][164][165][166][167] 2010

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