| abstract |
Cyclohexane derivatives have the formula R1-A1-Z1-A2-R2, wherein R1 and R2 are an alkyl group having between 1 and 10 C atoms and one or two non-adjacent CH2 groups may be substituted with O and / or by -CO- groups and / or by -CO-O- groups and / or by -CH = CH- groups, one of the radicals R1 and R2 possibly also being H, F, Cl, Br, CN or R3-A3-Z2, A1 is -A-, A4-A- or -A-A4-, A is trans-1,4-cyclohexylene group substituted one or more times in the second, third, fifth and / or in the sixth position by F and / or Cl and / or Br and / or CN and / or by an alkyl group or by a fluorinated alkyl group having between 1 and 10 C atoms and of which one or two non-adjacent CH2 groups can be substituted by O atoms and / or by -CO- groups and / or by -CO-O- groups. This substituted trans-1,4-cyclohexylene group can also be substituted, if necessary, at the first and / or at the fourth position. A2, A3 and A4 are 1,4-phenylene unsubstituted or substituted by one or two F and / or Cl atoms and / or by CH3 groups and / or by CN groups, and of which one or two CH groups may be substituted by N and / or NO atoms, or are 1,4-cyclohexylene of which one or two non-adjacent CH2 groups may be substituted by O atoms, or are 1,3-dithian-2,5-diyl, piperidin- groups 1,4-diyl, 1,4-bicyclo (2,2,2) -octylene, decahydronaphthaline-2,6-diyl or 1,2,3,4-tetrahydronaphthaline-2,6-diyl. Z1 and Z2 are -CO-O-, -O-CO-, -CH2CH2-, OCH2-, -CH2O or a single bond, and R3 is H, an alkyl group having between 1 and 10 C and of which one or two groups Non-adjacent CH2 may be substituted by O atoms and / or by -CO- groups and / or by -CO-O- groups and / or by -CH = CH- groups, or are F, Cl, Br o CN, provided that when Z1 = -CO-O-, A1 at the beta position relative to the -CO-O- bond does not have equatorial substituents. These derivatives are useful as components of liquid crystal phases. |