Tolane liquid crystals with piperidine, 3,3,4,4,5,5-hexafluoropiperidine as end group: Synthesis and properties

作者：Zhu Dezhao; Hong Fengying; Zhang Hong; Xia Zhengce; Wu Hongxiang; Jiang Qiwei; Wang Hui; Zeng Zhuo^*

来源：Journal of Molecular Liquids, 2015, 204: 84-89.

DOI：10.1016/j.molliq.2015.01.043

• Fluorine
• Liquid crystals
• Properties
• Heterocycles
• Mesophases

A series of new tolane liquid crystals with piperidine and 3,3,4,4,5,5-hexafluoropiperidine as their terminal groups were synthesized via Sonagashira reaction by using Pd(PPh3)(2)Cl-2/Cul as the catalyst. Their structures were modified by varying the terminal N-heterocycles and/or the length of the alkyl/alkoxy chains on the benzene ring. Most of these new compounds exhibit Smectic B or G mesophases, good thermal stabilities and high clearing points. The molecule C(2)H(5)O6F with 3,3,4,4,5,5-hexafluoropiperidine as the end group has a broader HOMO-LUMO energy gap and higher oxidation potential than piperidine derivative C(2)H(5)O6H. The result indicates that the oxidation resistance of the tolane liquid crystals was improved by introducing the terminal fluorinated piperidine.

• 单位
  华南师范大学; 中国科学院