Synthesis of Schiff Base-type Liquid Crystalline Crown Ethers Containing Dibenzo-18-Crown-6 Unit
Abstract
The synthesis and characterization of novel Schiff base liquid crystalline crown ethers prepared from the intermediates 4-(4′-alkoxylbiphenyl-4-carbonyl) benzaldehyde, cis- and trans-4,4′-diaminodibenzo-18-crown-6 are described. The structure of these compounds have been well characterized by elemental analysis, IR, 1H NMR and MS spectroscopy. The liquid-crystalline behavior of these compounds was also investigated by differential scanning calorimetry (DSC), polarizing optical microscopy (POM) with a heating stage and polarimetric analysis.