0000000001304724
AUTHOR
Nico Röder
Tetrakis(oxadiazolylphenyl)pyrazines: New St. Andrew's Cross-Shaped Liquid Crystals.
π-Conjugated molecules with the shape of St. Andrew's cross have been synthesized via fourfold Huisgen reaction. Four 2,5-diaryl-1,3,4-oxadiazol arms are attached to a central pyrazine nucleus. These fluorescent stars, when decorated with a rim of eight alkoxy side chains are discotic liquid crystals. Depending on the substitution pattern, the width of the liquid phase varies within a broad range of 25 °C to 250 °C. In their liquid crystalline phase, the molecules assemble in a typical hexagonal columnar supramolecular arrangement.
Isomerisation of Liquid-Crystalline Tristriazolotriazines
Star-shaped discotic liquid crystals with columnar superstructures constitute a highly interesting class of organic materials. Phenyl-substituted tris[1,2,4]triazolo-[1,3,5]triazine, prepared by a Huisgen reaction of phenyltetrazole and cyanuric chloride, represents an excellent core for discotic liquid crystals (DLCs). The thermal stability is not perfect, at temperatures above the clearing point, a successive threefold isomerization leads to a highly planar, C
CCDC 1826069: Experimental Crystal Structure Determination
Related Article: Nico Röder, Tomasz Marszalek, Daniel Limbach, Wojciech Pisula, Heiner Detert|2019|ChemPhysChem|20|463|doi:10.1002/cphc.201800936
CCDC 1539528: Experimental Crystal Structure Determination
Related Article: Thorsten Rieth, Nico Röder, Matthias Lehmann, Heiner Detert|2018|Chem.-Eur.J.|24|93|doi:10.1002/chem.201705095