SYNTHESIS OF NEW,HIGH-EFFICIENCY LIQUID CRYSTAL COMPOUNDS OF BETA-CYCLOHEXYL-ALFA,BETA-DIFLUOROSTYRENE CORE STRUCTURE

从1995年到1997年，考虑到实际应用，研究了具有-环己基- α - α - -二氟苯乙烯核心结构的新型高效液晶化合物的分子设计和合成。在碱性核心化合物的合成方面，研究了环己基锂的合成方法及其与四氟乙烯的反应，建立了以4-烷基环己醇为起始物的有效方法。在-环己基- α - β -二氟苯乙烯核心结构的液晶分子设计中，由于单个化合物的液晶相温度范围不同，很难设计出有效的氰基化合物。在STN-LC器件手性添加剂的分子设计和合成中，由于分子结构与手性添加剂的有效性关系较弱，因此很难预测有效化合物的分子结构。只要合成了一系列的苯甲酸甲酯，并对它们的物理性质进行了评价，就会发现螺旋节距与侧链长度近似成线性关系，而粘度则随侧链原子的偶数或奇数而上下变化。至于大规模的合成和纯化，还需要进一步研究低温氯化和与烷基金属化合物的反应。合成的某些步骤需要重新研究纯化方法。通过对新合成化合物的评价，发现了一些适合实际应用的有效化合物。在整个研究项目中，获得了有关液晶化合物的物理性质和分子结构的新的重要信息。但是，为了阐明其结构与性能的关系并进行分子设计，需要对具有不同官能团的化合物进行系统的合成和评价。少

Molecular design and synthesis of new, highly efficient liquid crystal compounds having beta-cyclohexyl-alfa, beta-difluorostyrene core structure have been investigated in view of practical application from 1995 through 1997.1. As to synthesis of the basic core compound, methods for generation of cyclohexyllithium and its reaction with tetrafluoroethylene were investigated and effective method was established using 4-alkylcyclohexanol as a atarting compund.2. As to molecular design of liquid crystal of beta-cyclohexyl-alfa, beta-difluorostyrene core structure, it turned out difficult to design effective cyano compounds because of different temperature ranges of liquid crystal phase for individual compounds.3. As to molecular design and synthesis of chiral additives for STN-LC devices, it proved to be difficult to predict molecular structure of effective compounds because of weak relationship between molecular structute and effectiveness as chiral additive. So long as a series of benzoa … More tes were synthesized and their physical properties were evaluated, an approximately linear relationship was observed between helical pitch and length of side chain, whereas viscosity changed up and down depending on the even or odd number of side chain atoms.4. As to synthesis and purification on a large scale, there will be need of further investigation for chlorination at low temperature and reactions with alkylmetal compounds. Purification method must be reinvestigated for some steps of the synthesis.5. Sone effective compounds were found for suitable practical application as the result of evaluation of newly synthesized compounds.Throughout this research project new and significant information was obtained regarding the physical properties and molecular structures of liquid crystal compounds. But systematic synthesis and evaluation of compounds having various functional groups will be required in order to clarify the structure-propertis relationship and to enable the molecular design. Less