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This paper reported not only the first fluorescein liquid crystals but also revealed the influence of peripheral alkyl chains on mesomorphic properties and photophysical properties. Novel fluorescein-triphenylene dimers 4a–4f with different alkyl chains were designed and synthesised in yields of 76–83%. Samples 4a, 4b, 4c and 4d with CH3 and C4H9 exhibited the columnar mesophase but samples 4e and 4f with C8H17 showed no mesophase. The longer alkyl chains on fluorescein units resulted in the lower phase transition temperature. The too long alkyl chain destroyed the liquid crystalline behaviour. Their fluorescence quantum yields were as high as 0.78–0.87 in CH2Cl2 solution and 0.11–0.17 in solid states. The longer alkyl chains leaded to the higher emission efficiencies. [ABSTRACT FROM AUTHOR]

By controlling the mol ratios of reactants, novel calix[4]resorcinarene–triphenylene monomer, dimer and tetramer were designed and synthesised in yields of 50–60% via Click chemistry. Their structures were characterised by NMR and MS. Their liquid crystalline behaviours were studied by differential scanning calorimetry, polarising optical microscopy and X-ray diffraction analysis. The more triphenylene units on calix[4]resorcinarene resulted in the wider temperature scopes of mesophase and higher phase transition temperatures. The monomer6and dimer7showed the mixed columnar mesophase with hexagonal columnar structure and disordered lamellar columnar structure, and compound8possessed only disordered lamellar columnar mesophase. These research results suggest that calix[4]resorcinarene was a good platform to construct columnar liquid crystal and the mesomorphic properties were greatly influenced by the substituted numbers of mesogen units on calix skeleton. [ABSTRACT FROM PUBLISHER]