Green synthesis of thioamide derivatives in an environmentally benign deep eutectic solvent (DES)

Abstract

A mild, direct, simple, and highly efficient green protocol is described for synthesizing thioamides. A wide variety of thioamides are obtained in good-to-excellent yields by the reaction of readily available starting materials, substituted aldehydes/ketones, secondary amines, and elemental sulfur in a choline chloride–urea (1 : 2)-based deep eutectic solvent (DES). This protocol, which can be applied without an additional catalyst support, contributes significantly to enhancing sustainability by reducing energy consumption and waste reduction, involving biodegradability, improved reactivity, and versatility. The DES can be recycled and used several times without any significant loss in terms of its activity.