A Facile Transformation of Terminal Olefins tovic-Difluoro Olefins: Electro-optical Properties of Liquid Crystalline Materials Having avic-Difluoro Olefinic Moiety
A Facile Transformation of Terminal Olefins tovic-Difluoro Olefins: Electro-optical Properties of Liquid Crystalline Materials Having avic-Difluoro Olefinic Moiety
A Facile Synthesis of Novel Liquid Crystalline Materials Having a Trifluoromethoxy Group and Their Electro-Optical Properties
作者:Kiyoshi Kanie、Sadao Takehara、Tamejiro Hiyama
DOI:10.1246/bcsj.73.1875
日期:2000.8
Novel liquid crystals (LCs) containing a trifluoromethoxy group connected to a cyclohexane mesogen or to an alkyl tail were prepared through an oxidative desulfurization-fluorination reaction of the corresponding dithiocarbonates. They were compared with LCs containing a methoxy group with respect to phase transition behavior and physical and electro-optical properties. Most of the CF3O-substituted LCs exhibited in a wide range of temperatures LC phases depending on the type of a mesogenic structure. LCs with a trifluoromethoxycyclohexane mesogen were shown to be thermally more stable than the LCs with a trifluoromethoxybenzene mesogen. LCs having a trifluoromethoxyalkyl tail show physical and electro-optical properties favorable to materials for not only TN-LCDs but TFT-addressed TN-LCDs. Furthermore, 3-β-CF3O-substituted cholestane was shown to be a potential chiral dopant for TFT-addressed TN-LCDs.
A Facile Transformation of Terminal Olefins to<b><i>vic</i></b>-Difluoro Olefins: Electro-optical Properties of Liquid Crystalline Materials Having a<b><i>vic</i></b>-Difluoro Olefinic Moiety
A facile synthetic method of vic-difluoro olefins from the corresponding olefins is explored and applied to the synthesis of liquid crystals (LCs) having a terminal vic-difluoro olefinic moiety. The physical and electro-optical properties of these LCs are compared with those of the corresponding parent olefinic LCs.