Obtenção do benzoato de fenila promovido por irradiação de micro-ondas

Abstract

Phenyl benzoate and its analogues are composed of various industrial applications, mainly in the pharmaceutical, flavoring and plasticizing industry. Given the difficulties of synthesis of these molecules, it is necessary to study new simple methodologies able to achieve high yields. The objective of this work was to promote the synthesis of phenyl benzoate through microwave irradiation, a more efficient way to supply energy, and without the use of solvents. For this, an Anton-paar Monowave 300 microwave equipment was used. Sulfamic acid and p-toluenesulfonic acid catalysts were used, where the latter was more efficient, reaching the highest conversion values. In addition to the type and quantity of catalyst, the values of the reaction temperature and reaction time parameters, and their influence on process conversion and selectivity were evaluated. In all experiments, the ratio of 5 mmol phenol and 4 mmol benzoic acid is constant. In addition, the magnesium sulfate desiccant was also kept constant and 0.3 equivalents were used. The optimum reaction condition was achieved by using p-toluenesulfonic acid at 10% concentration, 220 ° C and 10 minutes, reaching 100% conversion and 85.95% selectivity. Feasibility calculations of the method were performed, and it was estimated an increase in the value of the products by about 188.9%. Thus, it can be said that it was possible to perform the synthesis of phenyl benzoate using microwave irradiation, associating favorable reaction conditions to obtain good conversion in the synthesis process of the compound of interest. [resumo fornecido pelo autor]