The Same and not the Same. Similarities and Differences in the Resolution of Trans-Chrysanthemic Acid of Industrial Origin by the Enantiomers of Some Thermo-1-aryl-2-dimethylamino-1,3-propanediols

Similarities and differences in the resolution of trans-chrysanthemic acid of industrial origin by the enantiomers of some threo-1-aryl-2-dimethylamino-1,3-propanediols (MTDP), were discussed. X-ray crystal structures of the n salts have trans-ChA and MTDP revealed the peculiar features of two pseudopolymorphs. MTDP enantiomers were low cost, non-toxic, safe, and easily available from important precursors of thiamphenicol through a single straightforward reaction. Classical resolutions were based on the different solubility of diastereomers formed by interaction of the enantiomers with the enantiopure resolving agent. The results concluded that for an efficient and practical resolution the choice of a proper solvent is as essential as the choice of the resolving agent.