This paper explores the versatility and effectiveness of Deep Eutectic Solvent (DES) as an efficient catalyst cum reaction media for the preparation of biologically important 1,3‐ thiazolidin‐4‐one derivatives. This methodology was objected to overcome the limitations of the previously reported methods such as the use of expensive and toxic solvents, long reaction time and low yield. This protocol is rapid, environmentally benign, with good to high yield of products. The DES media could be reused up to five times without any appreciable decrease in the yield.

An environmentally benign methodology for the regioselective synthesis of an important class of imidazoheterocycles has been developed using choline chloride‐based deep eutectic solvent. It involves the coupling of 2‐amnopyrimidines, 2‐aminopyridines, and 2‐aminopyrazines with 2‐halocarbonyl compounds to get a variety of substituted imidazopyrimidines, imidazopyridines, and imidazopyrazines, respectively. This method is found to be expeditious, catalyst‐free, energy‐efficient with good yields of products and potential for scale‐up. Moreover, the eutectic solvent is inexpensive, biodegradable, non‐toxic, and recycled five times without any considerable loss in its activity.