A kinetic study of acid-catalysed reaction of 4-ethylphenol and acetone

摘要

The kinetic investigation of 4-ethylphenol with acetone in the presence of H~+ ions at 15.3×10~(-3), 31.4×10~(-3), 46.8×10~(-3) and 62.5×10~(-3) N HCI concentrations and at 35, 40, 45 and 50 +- 0.05deg C temkperatures has been carried out. The overall rate constants and the activation parameters have been evaluated. For 15.3×10~(-3), 31.4×10~(-3), 46.8×10~(-3) and 62.5×10~(-3) N HCI concentrations, the energies of activation are found to be 19.52, 17.28, 15.56 and 13.3 kcal mol~(-1) and the entropies of activation are -15.37, -21.74, -26.76 and -33.24 cal deg~(-1) mol~(-1) respectively. Effects of polarity and dielectric constant of the media on the reaction rate have also been ascertained. The overall rate constant was resolved into stepwise rate constnats. An execellent agreement between the experimental and calcualted values of k has been observed.