Choline Chloride/Urea as an Eco-Friendly Deep Eutectic Solvent for TCT-Mediated Amide Coupling at Room Temperature

A desirable alternative to organic solvents, very cheap, non-toxic and biodegradable deep eutectic solvent (DES) based on choline chloride and urea was introduced for 2,4,6-trichloro triazine mediated amide bond formation between carboxylic acids and amines at room temperature. Sub-stoichiometric amount of TCT was used as a cheap and readily available C-O activating reagent. Various derivatives of amines were coupled with carboxylic acids, via triacylated triazine intermediate, resulting the reaction of acids with TCT, and the corresponding amides were obtained in moderate to good yields.