Resolution studies on two regioisomeric chiral stationary phases: effects from reversed orientation of an amide group

Two new polymeric chiral stationary phases, incorporating the selectors trans-9,10-dihydro-9,10-ethanoanthracene-11,12-dicarboxylic acid bis-allylamide, 1 (DEABA) and trans-11,12-diamino-9,10-dihydro-9,10-ethanoanthracene bis-butenoylamide, 2 (DDEBB), respectively, have been evaluated by chromatographic resolution of a series of structurally different racemates. For some groups of compounds, where large separation factors were obtained, more detailed studies were performed by the use of different retention modifiers. As an effect from the reversed orientation of the amide group in the two selectors, the enantiomers of the racemates investigated are separated in opposite order of elution on the two columns.