Kinetic study of charge transfer interaction of substituted pyridines and substituted 4-styrylpyridines with <em>p-</em>bromanil

Abstract

Kinetics of charge transfer interaction of various 3- and 4-substituted pyridines and 4' –substituted 4-styrylpyridines with <em>p</em>-bromanil has been studied spectrophotometrically in carbon tetrachloride at three different temperatures and thermodynamic parameters have been evaluated. The reaction between pyridine and <em>p</em>-bromanil follows second order kinetics, first order in each reactant. Electron-releasing substituents in pyridine ring increase the rate of the charge-transfer interaction while electron- withdrawing substituents retard it. Good Hammett correlations have been observed in both the reaction series. The ratio of effectiveness of transmission of substitutent effect in styrylpyridine system relative to pyridine system in this reaction is computed to be 0.167.