Investigation of the Mannich reaction for generating a β-aminoketone: further treatment of kinetic results

Abstract

The aim of this study is the derivation of the kinetic parameters for a special Mannich reaction, where the first step is rate-determining. The work involved studying the reactions among benzaldehyde, acetophenone and aniline in the presence of sodium acetate as a catalyst for the generation a β-aminoketone. The novelty of this work lies in its investigation of the effect of the catalyst on kinetic behaviour that allows for estimations of the rate constant and activation parameters such as energy of activation, enthalpy, entropy and activation Gibbs free energy, relative to the formation of β-aminoketone. Experimentally, the reactions were found to be of second-order and the observed rate constants were determined using UV-vis spectrophotometry. The satisfactory agreement between the sets of experimental data obtained under different reaction conditions and the steady state assumption indicates that the assumptions made are correct and the whole treatment applied to the kinetic data is justified.

Keywords

• β-Aminoketone
• kinetic study
• benzaldehyde
• acetophenone
• aniline