Grindstone Chemistry: Facile Green Chemical Approach for the Synthesis of Pyran Scaffolds

Abstract

Chemical transformations through physical grinding of precursors using mortar and pestle are usually termed as ‘Grindstone Chemistry’. The main feature of this method such as does not require costly equipment, allows solvent and waste-free transformations under mild conditions, and normally involves short reaction time, high product yield and selectivity made this protocol attractive among unconventional synthetic approaches. On the other hand, Pyrans are important heterocyclic structures found applications in various fields of research including pharmaceuticals and materials. This review article summarizes the research reports on the construction of Pyran core heterocycles via Grindstone chemical synthesis. The greener parameters, reaction conditions, number of examples, product yield range of these reactions are highlighted.

Keywords: Grindstone Chemistry; Pyran; Multicomponent reactions; Chromenes; Heterocycles