Mechanochemistry Frees the Thiourea Dioxide (TDO) from the ‘Veils’ of the Solvent, Exposing All Its Reactivity

Abstract

The synthesis of nitrogen-based heterocycles has always been considered essential in the development of pharmaceuticals in medicine and agriculture. This explains why various synthetic approaches have been proposed in recent decades. However, performing as methods often imply harsh conditions or the employment of toxic solvents and dangerous reagents. Mechanochemistry is undoubtedly one of the most promising technologies currently used for reducing any possible environmental impact due to the worldwide interest in developing solvent-free synthetic pathways. Following this line, we propose a renewed mechanochemical protocol for synthesizing various heterocyclic classes by exploiting the reducing proprieties and the electrophilic nature of thiourea dioxide (TDO). Simultaneously using the ready availability and low cost of a component of the textile industry such as TDO and all the advantages brought by a green technique such as mechanochemistry, we plotted the route towards a more sustainable and eco-friendly methodology for obtaining heterocyclic moieties.