Flüssigkeits-Chromatographie an Triacetylcellulose 14: Separation of Enantiomers and Barriers to Enantiomerization of Axially Chiral Aromatic Carboxamides

Abstract

The enantiomers (M) and (P) of a series of similar aromatic carboxamides have been, for the first time, investigated analytically and enriched preparatively by liquid chromatography on triacetylcellulose. Enantiomeric purities (7–99%), specific rotations, and barriers to rotation about the C(sp–C(sp bond (87–120 kJ/mol, Table 5) were determined. These energies are discussed in terms of the size of ortho substituents and of the buttressing effects by meta substituents.