A novel way to prepare n-butylparaben under microwave irradiation

The synthesis of n-butylparaben under microwave irradiation in the presence of an inorganic salt ZnCl2 as a catalyst is reported. Using this specific catalyst for the synthesis of the n-butylparaben under microwave irradiation, not only shortens the reaction time, but also reduces the pollution from the use of concentrated sulfuric acid and prevents the complicated after-treatment handling problems. The reason for this type of microwave-assisted reaction is also demonstrated from the temperature profiles of the reaction. The ratio of the reactants for the better microwave energy efficiency is discussed. The use of microwave irradiation for the large-scale production of this type of food preservative is therefore feasible.