Recent advances in helical polyacetylene derivatives used as coated chiral stationary phases for enantioseparation

Chiral separation by high-performance liquid chromatography (HPLC) using a chiral stationary phase (CSP) is a reliable method for obtaining pure enantiomers for both analytical and preparative purposes. The development of effective CSPs is the key point of this technique. Among many synthetic polymers showing chiral recognition abilities, the helical polyacetylene derivatives with stereoregular structures showed excellent chiral recognition abilities as CSPs and are promising candidates as CSPs for HPLC. Dynamic helical polyacetylene derivatives can change their helical pitch and invert the helicity by changing their functional chiral pendants. The change of helical conformation will significantly influence their chiral recognition abilities. In this review, the development of helical polyacetylene derivatives bearing different kinds of chiral pendants (central chirality pendants, axial chirality pendants, planar chirality pendants, and helical chirality pendants) and the enantioseparation based on these helical polymers as coated CSPs for HPLC will be described. The chiral recognition potential of helical polyacetylene derivatives bearing spiro and multilayer 3D chirality pendants is discussed for future study. We hope this review will inspire more motivation to develop novel helical polyacetylene derivatives showing highly efficient chiral recognition and resolution ability for a wide range of racemates.