Green and multi-component synthesis of polyfunctionalized pyrrole derivatives under solvent-free condition

In the present research, the design and synthesis of polyfunctionalized pyrrole derivatives using one-pot, multi-component reactions including aromatic aldehydes, ethyl acetoacetate, thiadiazole derivatives, and nitromethane in the presence of 3-sulfonic acid 1-imidazolopyridinium hydrogen sulfate ([Simp]HSO4]) ionic liquid and under solvent-free conditions were discussed. Since pyrrole derivatives have various medicinal properties such as antibacterial, antiviral, anti-inflammatory, and antioxidant activity, and they are very important from biological and medicinal points of view, therefore, it is very important to provide efficient and green methods for preparing these compounds.On the other hand, considering the environmental pollution and the development of the green chemistry approach, and the recommendation to reduce the use of toxic solvents in chemical reactions, extensive research to find new synthetic methods based on the use of environmentally friendly solvents and catalysts that lead to the reduction of waste materials and products. This method used the ionic liquid 3-sulfonic acid 1-imidazolopyridinium hydrogen sulfate ([Simp]HSO4]) as a recoverable catalyst in the green synthesis of pyrrole derivatives.This method has some advantages such as high yield, no use of organic solvents, mild reaction conditions, short reaction time, and easy separation without using chromatography. The structure of all products was characterized using physical data as well as 1HNMR, 13CNMR and IR spectrum.