126334-32-5Relevant academic research and scientific papers
The synthesis and electro-optic properties of liquid crystalline 2- (2,3-difluorobiphenyl-4'-yl)-1,3-dioxanes
Dong, Chu Chuan,Styring, Peter,Goodby, John W.,Chan, Lawrence K. M.
, p. 1669 - 1677 (2007/10/03)
Fifty-six novel alkyl and/or alkoxy disubstituted 2-(2,3- difluorobiphenyl-4'-yl)-1,3-dioxanes (DFBPD) were prepared. Smectic C and nematic mesophases were exhibited by most of the alkyl-alkoxy homologues. Conversely, most of the dialkyl compounds exhibited smectic C, smectic A and nematic phases. The birefringence (Δn), dielectric anisotropy (Δε), spontaneous polarisation and response times of two ferroelectric mixtures formulated from the dioxanyl systems were determined. The birefringence results were compared with eight other groups of mixtures where the materials were based on different core systems. The overall electro-optic properties of the DFBPDs were found to be comparable to the best of the eight most commonly used materials in ferroelectric display devices.
Dioxane derivatives
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, (2008/06/13)
Dioxane derivatives for use as components in liquid crystal devices (LCDs) of general formula (A), wherein X is CH or B; R1, R2 are each A1, OA1, OCOA2, or COOA2 ; A1 is a straight or branched chain alkyl group containing from 1 to 20 carbon atoms and may be substituted with one or more F or CN. A2 is a straight or branched chain alkyl group containing from 1 to 20 carbon atoms and may be substituted with one or more F or CN and if straight may be unsubstituted. Y1, Y2, Y3 may each be (CH2)p, (CH2)p COO or OCO(CH2)p ; p is from 0 to 10, n is 0 or 1, m is 0 or 1, either or both of Z1 and Z2 are F and, when not F, are H; Y4 is a covalent bond or, when n is 0, may be (a) LCDs, containing the devices exhibit very fast switching speed, bi-stable characteristics, enhanced greyscale and storage capabilities and a wide viewing angle.
The Synthesis and Transition Temperatures of Some 4,4"-dialkyl- and 4,4"-Alkoxyalkyl-1,1':4',1"-terphenyls with 2,3- or 2',3'-difluoro Substituents and of their Biphenyl Analogues
Gray, George W.,Hird, Michael,Lacey, David,Toyne, Kenneth J.
, p. 2041 - 2054 (2007/10/02)
The tetrakis(triphenylphosphine)palladium(o)-catalysed coupling of arylboronyc acids with aryl halides is used to prepare several 4,4"-dialkyl- and 4,4"-alkoxyalkyl-1,1':4',1"-terphenyls with 2,3- or 2',3'-difluoro substituents and their related biphenyl systems.Lithiation ortho to a 1,2-difluoroaromatic unit provides the route to the 2,3-difluoroarylboronic acids.The 2,3-difluoro substituted terphenyls are low-melting liquid crystals with wide-range Sc phases and no underlying smectic phase; these compounds are excellent hosts for ferroelectric systems.The compounds with widest Sc ranges are those with the difluoro substituents in an end ring and the compounds with difluoro substituents in the central ring show more nematic character and so are useful for ECB devices.
