Kinetics of Alkali-Catalyzed 2,5-Dimethylphenol-Forrnaldehyde Reaction

A kinetic study of the reaction between 2,5-dimethylphenol (2,5-DMP) and formaldehyde has been carried out at 65, 70, 75, and 80 ± 0.05° C by using sodium hydroxide as the catalyst. The solvent mixture used in the kinetic experiments was 50% (v/v) methanol-water. The various alkali concentrations used were 0.003, 0.006, 0.010, 0.018 and 0.025 N. The reaction was found to obey second-order rate law. The rate of reaction was observed to increase with an increase in the alkali concentration. The effect of changing the reactant concentrations and the nature of the solvent was also studied. The overall rate constant has been resolved into stepwise rate constants. The entropy of activation and Arrhenius parameters for the overall reaction have also been calculated.