Conventional vs. microwave-assisted synthesis: A comparative study on the synthesis of tri-substituted imidazoles

Abstract

The organic and peptide synthesis, various nanotechnology, and biochemistry processes are being carried out using microwave irradiation. The use of microwaves for synthesis has increased in the past two decades. The microwave offers several advantages such as ease of handling, lesser reaction times, quality of the product, and eco-friendly, which is green. The conventional method of synthesis, on the other hand, requires a longer time, is difficult to handle and maintenance of temperature is also difficult. The use of microwave-assisted reactions over conventional methods is advantageous in medicinal chemistry research as they will be less time-consuming and crucial in drug discovery and development. On the other side, they might not work in bulk synthesis due to their limited capacity for loading the reaction mixture. The present work aims to compare reaction time, temperature and percentage of yield of the microwave-assisted synthesis method against the conventional method. A novel, simple, and green method was developed for the synthesis of tri-substituted imidazoles by microwave irradiation. Both derivatives from conventional and microwave-assisted synthesis were characterized by IR spectroscopy, Mass spectrometry, and 1H-NMR spectroscopy. The same derivatives were also synthesized by the conventional method for comparison. A comparison of both methods was made by comparing the reaction time and the percentage yield. It was found that microwave-assisted reactions produced greater yield in the minimal time, though at different reaction temperatures. It can be concluded from the present comparison study that the use of the microwave for synthesis provides numerous advantages; thus, newer molecules are developed quickly anthat are developed quickly. To further proceed in this direction and to produce evidences, synthesis of more derivatives may be required. The only disadvantage is that it cannot be used for bulk synthesis of the compounds.