Effects of Rigid Conjugated Groups: Toward Improving Enantioseparation Performances of Chiral Porous Organic Polymers

The construction of chiral porous materials for practical enantioseparation remains a great challenge. As chiral compounds might display a distinctive spatial orientation in diastereoisomeric complexes between enantiomers and selectors, we reasoned that the conjugated host framework might assist in chiral recognition and thus enhance enantioseparation performances. In this regard, as porous organic polymers (POPs) with chiral selectors are considered as ideal adsorbents, a new kind of POP, COP-1, was thus constructed via introducing an amino acid, as a chiral selector, into rigid and conjugated building blocks, in this work. Results show that the enantiomeric model molecule and drugs are completely separated by gas or column chromatography with COP-1 as chiral stationary phases. Both theoretical and experimental analyses demonstrate that the introduction of conjugated groups generates different host-guest interactions indeed and thus promotes the chiral separation performance. Our findings open up a new possibility for the practical application of enantioseparation at preparative scales.