Non-symmetric chiral liquid crystal dimers. Preparation and characterisation of the (S)-(benzylidene-4′-substitutedaniline)-2″-methylbutyl-4‴-(4″″-phenyloxy)-benzoateoxy)hexanoates
作者:Guan-Yeow Yeap、Faridah Osman、Corrie T. Imrie
DOI:10.1016/j.molstruc.2016.01.007
日期:2016.5
described. The terminal substituents on the 4-benzylidene-4′-substituted fragment are H, Cl, Br, I, CH 3 and C 2 H 5 . All six dimers exhibit an enantiotropic chiral nematic phase. The relationship between the chiral nematic-isotropic transition temperature and the terminal substituent is discussed in terms of the size of the substituent and its effect of the molecularshape, and its ability to interact
摘要 描述了属于 ( S )-(benzylidene-4'-locatedaniline)-2"-methylbutyl-4‴-(4""-phenyloxy)benzoate-oxy)己酸酯家族的六种手性非对称二聚体的性质。 . 4-亚苄基-4'-取代片段上的末端取代基是H、Cl、Br、I、CH 3 和C 2 H 5 。所有六个二聚体都表现出对映手性向列相。手性向列-各向同性转变温度与末端取代基之间的关系根据取代基的大小及其对分子形状的影响,以及与它所连接的介晶基团相互作用的能力进行了讨论。C 2 H 5 取代的二聚体还显示出对映单层手性近晶C相,其形成归因于更长的烷基链引起的增强的分子不均匀性。
Additional effect of para‐hydroxyl on the reduction potentials of the<i>N</i>‐benzylidenebenzenamines
作者:Chao‐Tun Cao、Wei Zhou、Chenzhong Cao
DOI:10.1002/poc.4028
日期:2020.3
(abbreviated as 4‐OHBAY or XBAOH‐4′) were synthesized, and their ERed values were measured. Then, 127 compounds were taken as a complicated ERed data set, which involved 28 compounds (4‐OHBAY and XBAOH‐4′) of this work and 99 compounds XBAY reported by Luo. Based on these data ERed set, through a quantitative regression analysis method and comparison of the factors affecting the ERed, the following results
Effect of substituents on the UV spectra of supermolecular system: Silver nanoparticles with bi-aryl Schiff bases containing hydroxyl
作者:Chao-Tun Cao、Shimao Cheng、Jingyuan Zhang、Chenzhong Cao
DOI:10.1002/poc.3910
日期:2019.3
Effect of substituents on the ultraviolet (UV) spectra of supermolecular system involving silver nanoparticles (AgNPs) and Schiffbases was investigated. AgNPs and 49 samples of model compounds (MC), bi‐aryl Schiffbases containing hydroxyl (XBAY, involving 4‐OHArCHNArY, 2‐OHArCHNArY, XArCHNAr‐4′‐OH, and XArCHNAr‐2′‐OH), were synthesized. The size of AgNPs was characterized by transmission electron
Novel Nonsymmetric Trimeric Liquid Crystals Exhibiting Glassy Nematic State at Low Temperatures
作者:Guan-Yeow Yeap、Tiang-Chuan Hng、Wan Ahmad Kamil Mahmood、Ewa Gorecka、Daisuke Takeuchi、Kohtaro Osakada
DOI:10.1080/15421400802198599
日期:2008.7.30
terminal atoms. The molecularstructure of these novel trimers is composed of six aromatic rings interconnected via two methylene spacers and three azomethine linking groups. In each molecule, the two identical methylene spacers vary from either C4H8 or C6H12. The trimers exhibit relatively low Tm and Tc (< 160°C). Three of the homologues with ethyl group are glassy nematic liquid crystals with Tg <
Abnormal effect of hydroxyl on the longest wavelength maximum in ultraviolet absorption spectra for bis-aryl Schiff bases
作者:Chao-Tun Cao、Wei Zhou、Chenzhong Cao
DOI:10.1002/poc.3672
日期:2017.10
4‐HOArCH=NArY and XArCH=NArOH‐4′, and the second set consists of 2‐HOArCH=NArY and XArCH=NArOH‐2′. Their ultravioletabsorptionspectra were measured and investigated. A very interesting phenomenon was observed by analyzing their wave number νmax (cm−1) of longest wavelength maximum λmax (nm) of ultraviolet. Compared with the change regularity of the νmax of XArCH=NArY (where the X and Y excluded OH), the