Mesomorphic Properties and X-Ray Diffraction Studies of 4-Alkanoyloxybenzylidene-4'-fluoroaniline

Abstract

Liquid crystals (LCs) are known as fourth state of matter, which own the anisotropic properties of crystals as well as fluid properties of liquids. It was first reported by Otto Lehman in 1889 after he investigated the double-melting points phenomenon of molten cholesteryl benzoate 1. The self-assembly properties of liquid crystals play a significant role in producing specific properties to a particular phase. This gives different order parameters in different mesophases 2. Liquid crystals found to be applied in display technology, advanced technological devices and prototypical self-organizing molecular materials 3. A minor structure modification results a great effect on the mesomorphic property. Therefore, in order to prepare a new mesogen with desirable property and application, it is essential to understand chemical structure-mesomorphic property relationships 4. Low-mass calamitic liquid crystals consisting of two aromatic rings with at least one terminal substituent, for instance, 4-methoxybenzylidene-4'-butylaniline (MBBA), are capable of showing liquid crystal properties 5,6. The discovery of 4-methoxybenzylidene-4'-butylaniline has sparked a renewed interest of researcher on Schiff bases due to its room temperature nematic phase 7-12 .

Synthesis and Structural Characterization of (E)-1-(4-Chlorobenzylidene)semicarbazide

“…Schiff bases are known to have biological activities such as antimicrobial [2][3][4] , antitumor 5 , mesomorphic 6 and herbicidal 7 properties. They have also been widely used as versatile ligands involved in various metal chelation reactions to form metal complexes [8][9][10][11][12][13][14][15][16] , which are very intreresting in many fields, such as biochemical activity [11][12][13] , catalysis and enzymatic reactions 14,15 and magnetism 16 .…”