2,6-二亚苄基环己酮液晶化合物的合成及性能研究

Synthesis of 2,6-bis(benzylidene)cyclohexanone and study of liquid crystal Behavior

以苯甲醛、环己酮为原料,四丁基溴化铵为相转移催化剂,在氢氧化钠溶液中合成了具有液晶性质的化合物2,6-二亚苄基环己酮.考察了反应时间、温度、碱浓度对产率的影响.产品经红外光谱、核磁共振氢谱以及元素分析予以表征,用差示扫描量热(DSC)、偏光显微镜和流变仪研究了其液晶行为,证明为近晶相热致液晶.对化合物晶体进行了X射线单晶衍射测定,证实属于单斜晶系,空间群P2(1)/c,a=9.586(1),b=18.391(2),c=9.433(1),α=90°,β=115.816(2)°,γ=90°,Dc=1.217g.cm-3,V=1496.9(3)-3,Z=4.

The liquid crystalline compound, 2,6-bis（benzylidene）cyclohexanone was synthesized using benzaldehyde and cyclohexanone as raw materials, and tetrabutyl ammonium bromide as phasetransfer catalyst in the solution of sodium hydroxide. Effect of many factors, such as reaction time, reaction temperature and concentration of sodium hydroxide, was studied. The product was confirmed by IR, ^1H-NMR and element analysis. The liquid crystalline behavior of compound was studied by DSC, optical polarizing micrographs and wideangle X-ray diffraction. The experimental results show that the synthesized compound exhibits typical semectic thermot ropic liquid crystal. Meanwhile, the crystal of compound was determined by X-ray single-crystal diffraction. The crystal of the compound belongs to monoclinic system with space group P2（1）/c, a=-9.586（1） A^°, b = 18.391（2） A^°, c = 9.433（1）A^°, α= 90°, β =115.816（2）°, γ= 90°, Dc= 1.217 g·cm^-3, V= 1496.9（3） A^°^-3, and Z= 4.