Enantioseparation on optically active poly(diphenylacetylene)s as chiral stationary phases for HPLC | Katsuhiro Maeda | Kanazawa University, Japan |

Kanazawa University, Japan

Enantioseparation by high performance liquid chromatography (HPLC) is recognized as one of the most popular and

eff ective methods for both analyzing the composition of enantiomeric mixtures and obtaining pure enantiomers, and

a large number of chiral stationary phases (CSPs) have been developed to resolve various racemates. Several optically active

helical poly(phenylacetylene)s bearing polar functional groups as a chiral recognition site have been reported to exhibit good

chiral recognition abilities toward some racemates due to the preferred-handed helical conformation when used as CSPs for

HPLC. On the other hand, the number of optically active poly(diphenylacetylene)s bearing polar functional groups reported so

far is very limited and poly(diphenylacetylene)-based CSPs have not yet been reported. In this study, we synthesized optically

active poly(diphenylacetylene) derivatives bearing amide groups as eff ective chiral recognition sites by the macromolecular

reaction of the optically inactive precursor poly(diphenylacetylene)s bearing carboxy groups with optically active amines and

investigated their chiral recognition abilities as CSPs for HPLC. Th e obtained polymers showed good chiral recognition ability

towards diverse racemates when used as CSPs for HPLC. Notably, the preferred-handed helical conformation was induced

on the polymer backbone by the thermal annealing process, which was applied aft er the introduction of the optically active

pendants via a polymer reaction. Th e chiral recognition abilities of the polymers with a preferred-handed helicity were greater

than those of the as-prepared polymers without a preferred-handed helicity. Th ese results indicated that the macromolecular

helicity induced in the polymer backbone by thermal annealing as a consequence of the eff ect of the chiral pendant groups was

playing an important role in the high chiral recognition ability of these poly(diphenylacetylene) derivatives.

Chromatography