Sono-synthesis of imidazolidine-2-thione as a base compound of some pharmaceutical products

This work describes the results of investigations carried out to investigate the synthesis of imidazolidine-2-thione as a heterocyclic compound in the presence of ultrasound (sono-synthesis) and in the absence of ultrasound (conventional method). Instead of reflux in the conventional method, the mixture was sonicated indirectly in sono-synthetic method with 500 kHz at different temperatures. Some experiments were also carried out without catalyst with 500 and 900 kHz. In the conventional method, the yield of the reaction was increased by increasing the temperature but in sono-synthetic method, the thermal dependence was different in the range of temperature studied (10–50 °C). In the presence of ultrasound, the yield was reached to more than 93% after 1 h but in the conventional method it reached only 27% under the same conditions. Comparison was carried out with and without catalyst. It is also possible to achieve a high yield of product under sonication without the use of a catalyst.