Synthesis and Liquid Crystalline Properties of New Diols Containing Azomethine Groups

Abstract

A series of new mesogenic azomethine diols were successfully synthesized by condensation reactions between various chloroalkanols and N,N'-bis(4-hydroxy)-benzylidene-o-toluidine (1). The structures of these compounds were confirmed by CHN, FT-IR, 1 H-NMR, and 13 C-NMR spectrophotometer. Their thermotropic liquid crystalline behavior was studied using differential scanning calorimetry (DSC) and polarizing optical microscope (POM). 4,4'-di(4-Hydroxybutoxy)-N-benzylidine-o-tolidine (2a) does not exhibit liquid crystalline properties. A nematic texture was observed for mesogenic diols 2b, and 2d, whereas the diol 2c exhibits a smectic mesophase. The increase of terminal alkyl chain in these mesogenic diols leads to a decrease in the transition temperature.

Synthesis of New Liquid Crystalline Diglycidyl Ethers

“…In addition, based on the 1 H-NMR spectrum depicted in Figure 2 , the presence of the oxirane ring was confirmed by the peaks appearing at 2.9–3.05 ppm as two doublets and at 3.49–3.57 ppm as multiplet. Two characteristic singlet peaks centered at 3.86 and 8.33 ppm [ 16 ] were due to the methoxy protons (-OC H 3 ) and the Schiff base protons (C H =N), respectively. A multiplet peak in the 7.05–7.85 ppm range was attributed to the protons in the aromatic rings.…”

,Polyazomethines. Synthesis, properties and applications (review)

“…Жидкокристаллические свойства не проявляют только диолы с n = 4. Диолы с n = 6 и n = 10 имеют энантиотропную нематичную фазу, а с n = 8 -смектическую мезофазу [128], как это показано на рис. 2.…”

Single-step green synthesis of imine-functionalized carbon spheres and their application in uranium removal from aqueous solution

“…The bands observed at 1509 and 1438 cm À1 were possibly due to C]C stretching and CH 2 deformation. 33 The band at 836 cm À1 may have represented the presence of C]CH bending vibrations. Other bands at 1357, 1179, 1096 and 1014 cm À1 were attributed to C-H, C-O, C-O-H and C-C stretching in the sugar, [34][35][36] which conrmed the involvement of glycosidic compounds in peCS synthesis.…”