One‐Handed Helical Tubular Ladder Polymers for Chromatographic Enantioseparation**

Abstract

Defect-free one-handed contracted helical tubular ladder polymers with a π-electron-rich cylindrical helical cavity were synthesized by alkyne benzannulations of the random-coil precursor polymers containing 6,6'-linked-1,1'-spirobiindane-7,7'-diol-based chiral monomer units. The resulting tightly-twisted helical tubular ladder polymers showed remarkably high enantioseparation abilities toward a variety of chiral hydrophobic aromatics with point, axial, and planar chiralities. The random-coil precursor polymer and analogous rigid-rod extended helical ribbon-like ladder polymer with no internal helical cavity exhibited no resolution abilities. The molecular dynamics simulations suggested that the π-electron-rich cylindrical helical cavity formed in the tightly-twisted tubular helical ladder structures is of key importance for producing the highly-enantioseparation ability, by which chiral aromatics can be enantioselectively encapsulated by specific π-π and/or hydrophobic interactions.

Oxepine-Based π-Conjugated Ladder/Step-Ladder Polymers with Excited -State Aromaticity

“…39,40 The exploration of oxepine in functional electronic materials or in polymers is extremely rare. 41 Recently, triptycene-22 and spirobiindane-based 24,26 ladder polymers with enantiopure helical ribbon/tube have been realized using the above-mentioned acid-induced electrophilic cyclization reaction as the postpolymerization annulation. This approach has broad utility in quantitative regioselective ring formation to produce ladder polymers.…”

“…Among the methods of postpolymerization modification, our group first reported a highly efficient acid-induced electrophilic cyclization reaction associated with the formation of six-membered rings to realize the synthesis of graphene-like π-conjugated ladder polymer . Over decades, this facile approach has been employed by our group and others to synthesize various ladder polymers and polycyclic aromatic systems. − …”

“…Recently, triptycene- and spirobiindane-based , ladder polymers with enantiopure helical ribbon/tube have been realized using the above-mentioned acid-induced electrophilic cyclization reaction as the postpolymerization annulation. This approach has broad utility in quantitative regioselective ring formation to produce ladder polymers. − However, the vast majority of electrophilic cyclization reactions on polymers produce five- or six-membered rings (Scheme a,b). As a result, we were interested in exploring new challenges in ladder polymer synthesis by introducing seven-membered oxepine rings in the polymer backbone (Scheme c).…”

Influence of Backbone Ladderization and Side Chain Variation on the Orientation of Diketopyrrolopyrrole-Based Donor-Acceptor Copolymers

“…An exceptionally high charge mobility for high-performance electronics was recently observed [ 9 ]. In addition, they have the potential to reduce the energy consumption and costs of industrial chemical separations [ 10 ] and can be highly enantioselective [ 11 ]. Even polymer lasers and all-optical devices based on the principle of strong light–matter coupling are possible and under investigation [ 12 ].…”