Μechanοchemistry applied tο Enantiοpurificatiοn thrοugh Deracemizatiοn : Frοm a prοοf οf cοncept tο a mechanistic study

Enantiopurification processes are of major concern in particular for the pharmaceutical industry. However, the currently used methods to achieve pure chiral solids are not consistent with the 12 principles of green chemistry. Our investigation aims to transfer the current solution-based processes to mechanochemistry, an emerging field that enables chemical reactions in the solid-state through mechanical action. To this end, we focus on (i) racemization of a widely sold active pharmaceutical ingredient, (ii) deracemization of racemic mixtures and (iii) enantiodirection during the mechanochemical deracemization. Through this study we confirm the high efficiency of mechanochemistry with regard to enantiopurification (faster kinetics) and its adaptability on several chiral systems. We also propose a consistent mechanismoccurring upon mechanochemical treatment and based on solid-state transformations.These successful investigations expand the toolbox of enantiopurification processes that could potentially be transferred to an industrial scale.