Synthesis and Low-Temperature Properties of Lateral Difluoro-Diphenyltolane Compounds

The lateral difluoro-diphenyltolane compounds (Ⅵ) with low viscosity,high birefringence were synthesized.Their structures were determined by IR,1H-NMR,13C-NMR,19F-NMR and MS.The transition temperature of liquid crystal phase and phase states were measured by DSC and POM.Their birefringence and viscosities at different temperature were also tested and analyzed.Experimental results show that the compounds synthesized exhibit high birefringence (Δn≈0.32),have lower viscosities and smaller temperature dependence at low temperature,comparing with the other relative structure of tolane compounds.These compounds are particularly attractive for reducing the viscosity of liquid crystal materials and achieving fast response times in LCD.