Novel diphenylacrylonitrile-decorated cyclotriveratrylene columnar liquid crystals with high fluorescence

Although some cyclotriveratrylene (CTV) liquid crystals had been reported, the CTV liquid crystal with high fluorescence in mesophase was not presented up to now. By introducing diphenylacrylonitrile units on CTV skeleton, two CTV derivatives with AIE units (7a and 7b) were prepared for the first time. Their structures and crown conformations were characterised by 1H NMR, 13C NMR, MALDI-MS spectra and elemental analysis. Samples 7a and 7b exhibited the reversible liquid crystalline behaviours with hexagonal columnar mesophase supported by the DSC, POM and XRD analysis. The studies on photophysical properties of samples 7a and 7b suggested the high fluorescence in solid state and mesophase. The absolute fluorescence quantum yield of 7b in mesophase was as high as 0.45. This work not only reported the first CTV liquid crystals with high fluorescence in aggregated state but also provided a good strategy for constructing the novel CTV liquid crystals with excellent fluorescence.