Al-Zahrani Salma A, Ahmed Hoda A, El-Atawy Mohamed A, Abu Al-Ola Khulood A, Omar Alaa Z
Department of Chemistry, College of Sciences, University of Ha'il, Ha'il 2440, Saudi Arabia.
Department of Chemistry, Faculty of Science, Cairo University, Cairo 12613, Egypt.
Materials (Basel). 2021 May 16;14(10):2587. doi: 10.3390/ma14102587.
Four new non-symmetrical derivatives based on central naphthalene moiety, 4-((4-(alkoxy)phenyl) diazenyl)naphthalen-1-yl 4-substitutedbenzoate (), were prepared, and their properties were investigated experimentally and theoretically. The synthesized materials bear two wing groups: an alkoxy chain of differing proportionate length (n = 6 and 16 carbons) and one terminal attached to a polar group, X. Their molecular structures were elucidated via elemental analyses and FT-IR and NMR spectroscopy. Differential scanning calorimetry (DSC) and polarized optical microscopy (POM) were carried out to evaluate their mesomorphic properties. The results of the experimental investigations revealed that all the synthesized analogues possess only an enantiotropic nematic (N) mesophase with a high thermal stability and broad range. Density functional theory (DFT) calculations were in accordance with the experimental investigations and revealed that all prepared materials are to be linear and planar. Moreover, the rigidity of the molecule increased when an extra fused ring was inserted into the center of the structural shape, so its thermal and geometrical parameters were affected. Energy gap predictions confirmed that the derivative is more reactive than other compounds.
制备了四种基于中心萘部分的新型不对称衍生物，即4-((4-(烷氧基)苯基)重氮基)萘-1-基4-取代苯甲酸酯（），并对其性质进行了实验和理论研究。合成的材料带有两个侧翼基团：不同比例长度的烷氧基链（n = 6和16个碳）和一个连接到极性基团X的末端。通过元素分析、傅里叶变换红外光谱和核磁共振光谱对它们的分子结构进行了阐明。进行差示扫描量热法（DSC）和偏光显微镜（POM）以评估它们的介晶性质。实验研究结果表明，所有合成类似物仅具有热稳定性高且范围宽的单变向列相（N）中间相。密度泛函理论（DFT）计算与实验研究一致，表明所有制备的材料都是线性和平坦的。此外，当在结构形状中心插入一个额外的稠环时，分子的刚性增加，因此其热参数和几何参数受到影响。能隙预测证实该衍生物比其他化合物更具反应性。
