New methylene cyclohexane cpds. and new optically active cpds. - used in liquid crystal compsn., esp. dielectric for matrix cpd.

摘要

New methylene-cyclohexane derivs. of formula (I) and new optically active methylenecyclohexane derivs. of formula (VIII) are claimed: R1 = 1-5C alkyl, alkenyl or perfluoroalkyl, opt. with one CN, halogen or CF3 substits., in which one or more CH2 gps. may be replaced by -S-, 1,3-cyclobutylene, 1,3-bicyclo(1,1,1)pentylene, -O-, -CO-, -CO-O, -O-CO-, or -O-CO-O but S and/or O atoms are not linked directly to one another; A1 and A2 independently = (a) trans-1,4-cyclohexylene, in which one or more non-adjacent CH2 gps. may be replaced by -O- and/or -S-; (b) 1,4-phenylene, in which one or 2 CH gps. may be replaced by N; (c) a 1,3-cyclobutylene, 1,3-bicyclo(1,1,1)pentylene, 1,4-cyclohexenylene, 1,4-bicyclo(2,2,2)octylene, piperidin-1,4-diyl, naphtha-2,6-diyl, decahydronaphtha-2,6-diyl or 1,2,3,4-tetrahydronaphtha-2,6-diyl gp.; and gps. (a) and (b) may be substd. by CN or halogen; Z1 and Z2 independently = -CH2CH2-, -CC-, -CH2O-, -OCH2-, -CO-O-, -O-CO-, -CH=N, -N=CH-, -CH2S-, -SCH2-, a single bond or a 3-6C alkylene gp., in which one CH2 gp. may be replaced by -O-, -CO-O-, -O-CO- -CH(halogen)-or -CH(CN)-; m = 0, 1, 2 or 3; X = H, C or Cl; Y = F, Cl or CF3; X and Y are different in (VIII); L5 = OH, COOH or a reactive deriv., OH, Cl, Br, I, CH2OH, CH2Cl, CH2Br or CH2I. USE/ADVANTAGE - (I) are claimed for use in liquid crystalline media for electrooptical displays and esp. as chiral component in chiral tilted media with achiral and chiral components, partic. for use as dielectric in matrix LCDs. (I) are stable liquid crystalline or mesogenic cpd. and give media with relatively low viscosity and medium positive dielectric anisotropy. (I) with suitable reactive gps. may also be incorporated in polymers or polycondensates.