Synthesis, Characterization and Study the Liquid Crystalline Properties of Some New Bent Compounds Derived from Diethylpyrimidine-۲,۴,۶(۱H,۳H,۵H)-Trione

This article includes designed and synthesized for bent-shaped liquid crystal molecules starting from ۵,۵-diethylpyrimidine-۲,۴,۶(۱H,۳H,۵H)-trione and two moles of chloroacetylchloride in N, N-dimethyl formamide (DMF) and triethylamine (TEA) to product compound [I] ,then reacted the later compound with two moles of ۴-hydroxybenzonitrile to yield nitrile compound [II]. Likewise, reaction ۵,۵-diethylpyrimidine-۲,۴,۶(۱H,۳H,۵H)-trione and two moles of ethylchloroacetate with fused sodium acetate in ethanol to create an ester compound [III], and then the later compound was reacted with two moles of hydrazine hydrate in ethanol to obtained hydrazide acid compound [IV]. After that, the compound [IV] reacted with two moles of ethyl acetoacetate in ethanol to synthesis compound [V]. The chemical structure of synthesis compounds was studied using FT-IR, ۱H-NMR, ۱۳C-NMR, and mass spectroscopy. Polarized optical microscope (POM) and differential scanning calorimetry (DSC) were used to examine the mesomorphic behaviour. The compound [II] with cyano terminal group showed nematic phase only on heating at ۱۵۹ °C.

کلیدواژه ها:

Bent shaped ، thermotropic liquid crystals ، Heterocyclic ، mesophase ، Nematic phase