Complete solid state deracemization by High Pressure Homogenization

In this work, we present High Pressure Homogenization as a novel approach to carry out attrition-enhanced deracemization, or Viedma Ripening. This is a process which leads to the conversion of a racemic or scalemic solid phase to an enantiomerically pure solid phase. The effect of pressure drop and homogenizer temperature on the evolution of deracemization of the compound N-(2-methylbenzylidene)-phenylglycine amide (NMPA) has been studied. Results prove the feasibility of the technique to achieve complete solid state deracemization, even without a substantial initial enantiomeric excess, and highlight low processing times. The effect of the homogenizer temperature has been demonstrated as a key parameter in HPH processing. These results establish the basis of High Pressure Homogenization as a new effective technique for Viedma ripening and open new possibilities for further development of solid state deracemization. [Display omitted] •Application of High Pressure Homogenization to solid state deracemization.•Ball mill-free deracemization in only a few hours.•Combination of temperature cycling and comminution to achieve fast processing.•Identification and explanation of effect of both temperature and comminution.