Narazaki Yu, Nishikawa Hiroya, Higuchi Hiroki, Okumura Yasushi, Kikuchi Hirotsugu
Interdisciplinary Graduate School of Engineering Sciences, Kyushu University 6-1, Kasuga-koen Kasuga Fukuoka 816-8580 Japan.
Institute for Materials Chemistry and Engineering, Kyushu University 6-1, Kasuga-koen Kasuga Fukuoka 816-8580 Japan
RSC Adv. 2018 Jan 3;8(2):971-979. doi: 10.1039/c7ra12465a. eCollection 2018 Jan 2.
A new series of chiral dopants, ()-6,6'-halogenated (1b-1e, X = F, Cl, Br and I) and -methylated (1f) binaphthyl compounds, were designed and synthesized to create chiral liquid crystals by doping them into an achiral nematic liquid crystal (NLC). The influence of halogen (X = F, Cl, Br and I) and methyl substituent factors, such as steric, polar, and polarizability properties, on the helical twisting power (HTP) and their temperature dependences on the chiral dopants were investigated in two host NLCs with different characteristics, fluorinated JC-1041XX and -(4-methoxybenzylidene)-4-butylaniline (MBBA). The chiral dopants possessing less steric and larger polarizability factors increased the HTP values. The structural similarity and electrostatic arene-arene interactions between the chiral dopants and the NLC molecules also exerted important influences on these values. The temperature dependence of the HTP (HTP) values also correlated well with the steric and polarizability substituents factors in the two host NLCs. Their correlation coefficients ( ) depended on the molecular structural similarity between the chiral dopant and the NLC.
设计并合成了一系列新型手性掺杂剂，即（）-6,6'-卤代（1b - 1e，X = F、Cl、Br和I）以及 - 甲基化（1f）联萘化合物，通过将它们掺杂到非手性向列相液晶（NLC）中来制备手性液晶。在两种具有不同特性的主体NLC（氟化的JC - 1041XX和 -（4 - 甲氧基亚苄基）-4 - 丁基苯胺（MBBA））中，研究了卤素（X = F、Cl、Br和I）以及甲基取代基因素（如空间位阻、极性和极化率特性）对螺旋扭曲力（HTP）及其对手性掺杂剂的温度依赖性的影响。具有较小空间位阻和较大极化率因素的手性掺杂剂会提高HTP值。手性掺杂剂与NLC分子之间的结构相似性和静电芳烃 - 芳烃相互作用也对这些值产生重要影响。HTP值的温度依赖性在两种主体NLC中也与空间位阻和极化率取代基因素密切相关。它们的相关系数（）取决于手性掺杂剂与NLC之间的分子结构相似性。
