Investigating the Role of Natural Deep Eutectic Low Melting Mixtures for the Synthesis of Symmetrical Bisamides

Keeping in view the fundamental significance of bisamides in nature, medicine, and biological systems in addition to their utility in chemistry of synthons, there is a tremendous need to develop environmentally benign synthetic methodologies for the construction of bisamides and their congeners. Herein, for the first time, we report a green and highly efficient method for the synthesis of diverse symmetrical bisamides in good to excellent yields through the condensation of diverse aromatic aldehydes with amides under operationally simple reaction conditions. The present strategy involves a renewable, biodegradable, and reusable, natural deep eutectic mixture of choline chloride and L-(+)-tartaric acid in the ratio of 2 : 1 at 100 degrees C for the generation of a range of bisamides. Moreover, we have fruitfully assembled diverse urea-based symmetrical bisamides with the usage of a low melting mixture of L-(+)-tartaric and urea (1 : 4) in decent yields. On large scale synthesis, both the methods were also found to be quite effective which leads to the formation of desired bisamides without significant decrease in the yields, thereby revealing their significance from industrial as well as academic viewpoint.