Intermolecular organization of triphenylene-based discotic mesogens by interdigitation of alkyl chains

Two homologous series of 2,3,6,7,10,11-hexa-alkyloxy-substituted triphenylenes have been synthesized, such that alkyl chains of two different lengths alternate around the rigid triphenylene core in order to allow interdigitation of the chains between neighbouring columns in a hexagonal columnar mesophase. We report here the dependence of structural and thermal properties on the extent of interdigitation, as investigated by X-ray diffraction, polarized optical microscopy and differential scanning calorimetry.