Role of Additives during Deracemization Using Temperature Cycling
Giuseppe Belletti1, Hugo Meekes1, Floris P J T Rutjes1
1Radboud University, Institute for Molecules and Materials, Heyendaalseweg 135, 6525 ED Nijmegen, The Netherlands.
Abstract:
Temperature cycling, alongside Viedma ripening, has been established as a reliable method for deracemizing racemic mixtures of chiral compounds that crystallize as a conglomerate. Here we report that the speed of temperature cycling can be increased by using chiral additives. We also demonstrate that the chirality of the additive determines the final enantiomeric state of the solid phase. Viedma ripening experiments using equivalent conditions, with and without chiral additives, are always found to be slower.
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