3b01 Unique Molecular Assembly of Discotic Liquid Crystalline Triphenylene Hexacarboxylic Esters

Abstract

Triphenylene has been widely used for a mesogenic core for discotic liquid crystalline (LC) materials. However, its LC derivatives, possessing side chain (R) via a -C(O)OR- type ester linkage, have not been studied so far. Recently, we investigated on the assembling behaviors of a series of LC TP(CO_2C_nH_<2n+1>)_6 and demonstrated that a dipole-dipole interaction among their ester carbonyl groups enables an exceptionally wide-range 2D lattice correlation in hexagonal columnar LCs. Being encouraged by this finding, we newly designed TP(CO_2R)_6 with semifluoroalkyl terminal chains. Since fluoroalkyl chains are known to aggregate strongly, we expected that such an interaction among fluoroalkyl side chains, in addition to the dipole-dipole interaction, could lead to further enhancement of 2D lattice correlation. Here, as an extension of our previous work, we also investigated the phase behavior of a TP(CO_2R)_6 derivative carrying imidazolium ion-appended paraffinic side chains.