Upper/lower rim functionalized calixarene based AIE-active liquid crystals with self-assembly behavior: Photophysical and electrochemical studies

Four novel bowl-shaped aggregation-induced emission (AIE)-active liquid crystalline compounds based on calix[4]arene having upper/lower unit functionalized by amide group and carrying six peripheral alkoxy chains were prepared. Their mesogenic, electrochemical, and photoactive properties were extensively examined. X-ray diffraction (XRD) studies showed columnar type self-assembly behavior of materials (10a-10d) possessing alkyl chains of varying lengths with D-A-π-D systems. The thermal study of all the materials was examined by DSC and TGA analysis. Their electrochemical studies were identified by cyclic voltammetry. The synthesized material showed light blue emission in solution as well as thin-film under long UV light. The characterization of newly synthesized materials was accomplished by spectroscopic techniques like IR, HRMS, 1H NMR, and 13C NMR. These supramolecular amide-thiadiazole linked compounds displayed enantiotropic columnar mesophase with good thermal stability. This new class of upper functionalized three-dimensional supramolecular materials exhibited AIE and stabilized the columnar hexagonal phase with a higher temperature range.