The (R)-and (S)-baclofenium hydrogenomaleate system exhibits an extensive chiral discrimination in the solid state at room temperature. Nevertheless, above 145 °C, the critical temperature, a complete solid solution between the two enantiomers is stable. The 50−50 mixture does not form any racemic compound at any temperature, and at 20 °C, the two mirror phases show limited symmetrical solid solutions as the enantiomeric excess equals 98.5%. This is due to a large miscibility gap in the solid state. Close to room temperature, the racemic mixture can be resolved by preferential crystallization. The yield of the process can be enhanced in acidic aqueous solutions (e.g., in HCl aq 2 M), which increases the solubility.

Deracemization extended to racemic-compoundforming systems is demonstrated. We present here the first results of an alternative for the resolution of systems that exhibit a stable racemic compound but also a closely related conglomerate-forming system. If the couples of enantiomers forming the racemic compound and the enantiomers of the stable conglomerate can syncrystallize in mirror-related partial solid solutions, it is possible to deracemize the racemic mixture of mixed crystals to access to a single handedness. The evidence for this possibility is given in three examples by using temperature-cycling-induced deracemization.

Starting from a deracemizable conglomerate (blue and red cubes), it is possible to substitute in the solid‐state part of the blue and red enantiomers with chemically related enantiomers (green and yellow cubes) that crystallize as a racemic compound. The mirror‐image solid solutions (enriched mixed crystals) could be deracemized by temperature cycling (deracemized mixed crystals). More information can be found in the Research Article by G. Coquerel and co‐workers (DOI: 10.1002/chem.202300441).