Discotic mesogens were synthesized by esterification of 1,3,5-tris(4-hydroxy- benzoyloxy)benzene with 3,4,5-trialkyloxybenzoic acids in DCC/DMAP/THF. These derivatives were studied by optical microscopy, differential scanning calorimetry and powder X-ray diffractometry. Optically uniaxially negative columnar phases were observed for derivatives having dodecyloxy and hexadecyloxy chains. Hexagonal packing of columns was observed from the results of X-ray diffraction. However, the diameter of the column is less than the molecular dimension indicating the interdigitations of peripheral chains of the neighboring columns.
Relation:
Molecular crystals and liquid crystals 411, pp.313-318
