Synthesis, characterization, and studying of (thermal, spectral and physical) properties of new Schiff base monomers and liquid Crystal compounds from Ampicillin

This work presents syntheses of six new Schiff base compounds from Ampicillin, p-hydroxyl Benzaldehyde reacted with (pentanol, hexanol, and heptanol) to produce (4-pentloxy, 4- hexaloxy, and 4- hepteloxy) Benzaldehyde, and compounds (phydroxy, p- chloro, p-nitro) Benzaldehyde used to produce Schiff base compounds. The prepared compounds have been identified using (FT-IR and H1-NMR) techniques. The microscopic phases were determined using a polarized light microscope (POM), and the thermal properties of the transition temperatures for these compounds were measured using a differential scanning calorimeter (DSC). All compounds melting points, colors, and yields were detected. Then the liquid crystalline behavior was studied, which showed that the compounds gave liquid crystalline properties and determined whether the compounds gave the nematic phase or the smectic phase.