Structural and analytical powder diffraction studies of the enantioselective inclusion of chiral arylmethylsulfoxides in dehydrocholic acid cocrystals

Dehydrocholic acid (DHA) has been employed in the separation of chiral arylmethylsulfoxides through selective precipitation of highly enriched 1:1 cocrystals of p-XC6H4SOMe@DHA (X = Me, OMe, Br, H) formulation. X-ray powder diffraction (XRPD) has shown that two, nearly isomorphous, but distinct classes of compounds are obtained. Their complete structural analysis has been performed by ab initio XRPD methods. Comparative quantitative analysis of the solid phases by X-ray methods and GC measurements of the R : S enantiomeric ratio allowed the assessment of the vicariancy (i.e., site substitution) probability of the R and S enantiomers in the different crystal phases.