Optically active distorted cyclic triptycenes: chiral stationary phases for HPLC.

A pair of optically active triptycene derivatives (( R , R )- and ( S , S )-8) with a distorted cyclic structure were synthesized via an intramolecular etherification and evaluated as a novel chiral selector for high-performance liquid chromatography. The ( R , R )- and ( S , S )-8-based chiral stationary phases (CSPs) were found to be particularly effective in the resolution of axially chiral biaryl compounds. The importance of the distorted cyclic structure present in 8 for chiral recognition was demonstrated by comparisons with the corresponding non-cyclic model compound (( R , R )-9), which did not display enantioselectivity in the separation of the test racemates.