Anisotropic compounds and liquid crystal mixtures therewith

Abstract

Anisotropic compounds of the formula (1) specified in claim 1 are suitable, owing to their low DELTA epsilon / epsilon ORTHOGONAL values for liquid crystal displays which have high information densities of for examples up to 106 image dots and accordingly need to be highly multiplexible; compared with known compounds they offer improved application properties and are relatively simple to synthesize.

We claim: 
     
       1. A compound of the formula ##STR15## in which R is an alkyl, alkoxy, or alkanoyloxy group which has in each case 1-12 C atoms in the alkyl moiety and which has a straight or branched and chiral or non-chiral chain, X 2  and X 3  are independently hydrogen, halogen or nitrile, X 4  is halogen or nitrile, Z is the ether oxygen bridge --O-- and m and n are independently 0, 1 or 2 with the provisos that (a) the sum of n and m is at least 1 and at most 3, and   (b) at least one of the groups X 2  and X 3  is not hydrogen.   
     
     
       2. A compound according to claim 1, wherein R is an alkyl group having 1-12 C atoms. 
     
     
       3. A compound according to claim 1 or 2, wherein halogen is fluorine or chlorine. 
     
     
       4. A compound according to claim 1, wherein one of X 2 , X 3  is a halogen atom and the other is hydrogen. 
     
     
       5. A compound according to claim 1, of the formula ##STR16## in which R, X 2 , X 3  and X 4  have the meaning specified in claim 1 and m 1  if 0 or 1. 
     
     
       6. A compound according to claim 5, wherein R is an alkyl group having 1-12 C atoms. 
     
     
       7. A compound according to claim 5 or 6, wherein X 4  is a nitrile group and one of X 2 , X 3  is a halogen atom and the other is hydrogen. 
     
     
       8. A compound according to claim 5 or 6, wherein X 2  is fluorine. 
     
     
       9. A compound according to claim 6 .[.or 7,.]. wherein X 3  is fluorine or chlorine. 
     
     
       10. A compound according to claim 1, of the formula ##STR17## in which R, X 2 , and X 3  and X 4  have the meaning specified in claim 1. 
     
     
       11. A compound according to claim 10, wherein R is an alkyl group having 1-12 C atoms. 
     
     
       12. A compound according to claim 10 or 11, wherein X 4  is a nitrile group and one of X 2 , X 3  is a halogen atom and the other is hydrogen. 
     
     
       13. A compound according to claim 10 or 11 wherein X 2  is fluorine. 
     
     
       14. A compound according to claim 10 or 11 wherein X 3  is fluorine or chlorine. 
     
     
       15. In a liquid crystal mixture having at least two liquid crystal components; the improvement wherein at least one such component is a compound of claim 1. 
     
     
       16. In an electro-optical display element with multiplex operation comprising a liquid crystal mixture as dielectric, the improvement wherein the mixture is one of claim 15. .Iadd. 
     
     
       17.  A compound of the formula (8) ##STR18## wherein R is an alkyl, alkoxy, alkenyl or alkanoyloxy group which has in each case 1-12 C atoms in the alkyl moiety and which has a straight or branched and chiral or non-chiral chain, X 2  and X 3  are independently hydrogen, halogen or nitrile, and   Halogen is fluorine or chlorine,   with the proviso that at least one of the groups X 2  and X 3  is not hydrogen..Iaddend..Iadd.   
     
     
       18.  A compound of claim 17, wherein R is alkyl of 1-12 C atoms..Iaddend..Iadd.19. A compound of claim 17, wherein X 2  and X 3  are H, F or Cl..Iaddend..Iadd.20. A compound of claim 17, wherein one of X 2  and X 3  is F and the other is H..Iaddend..Iadd.21. A compound of claim 17, wherein X 2  is H, X 3  is F and Halogen is F..Iaddend..Iadd.22. A compound of claim 20, wherein halogen is Cl..Iaddend..Iadd.23. A compound of claim 17 which is 2-(4-trans-4-propyl-4'-bicyclohexyl)-1-(4-chloro-2-fluorophenyl)ethane   2-(4-trans-4-pentyl-4'-bicyclohexyl)-1-(4-chloro-2-fluorophenyl)ethane   2-(4-trans-4-heptyl-4'-bicyclohexyl)-1-(4-chloro-2-fluorophenyl)ethane   2-(4-trans-4-propyl-4'-bicyclohexyl)-1-(4-chloro-3-fluorophenyl)ethane   2-(4-trans-4-pentyl-4'-bicyclohexyl)-1-(4-chloro-3-fluorophenyl)ethane   2-(4-trans-4-heptyl-4'-bicyclohexyl)-1-(4-chloro-3-fluorophenyl)ethane   2-(trans-4-methyl-4'-bicyclohexyl)-1-(2,4-difluorophenyl)ethane   2-(trans-4-ethyl-4'-bicyclohexyl)-1-(2,4-difluorophenyl)ethane   2-(trans-4-propyl-4'-bicyclohexyl)-1-(2,4-difluorophenyl)ethane   2-(trans-4-butyl-4'-bicyclohexyl)-1-(2,4-difluorophenyl)ethane   2-(trans-4-pentyl-4'-bicyclohexyl)-1-(2,4-difluorophenyl)ethane   2-(trans-4-hexyl-4'-bicyclohexyl)-1-(2,4-difluorophenyl)ethane   2-(trans-4-heptyl-4'-bicyclohexyl)-1-(2,4-difluorophenyl)ethane   2-(trans-4-methyl-4'-bicyclohexyl)-1-(3,4-difluorophenyl)ethane   2-(trans-4-ethyl-4'-bicyclohexyl)-1-(3,4-difluorophenyl)ethane   2-(trans-4-propyl-4'-bicyclohexyl)-1-(3,4-difluorophenyl)ethane   2-(trans-4-butyl-4'-bicyclohexyl)-1-(3,4-difluorophenyl)ethane   2-(trans-4-pentyl-4'-bicyclohexyl)-1-(3,4-difluorophenyl)ethane   2-(trans-4-hexyl-4'-bicyclohexyl)-1-(3,4-difluorophenyl)ethane, or   2-(trans-4-heptyl-4'-bicyclohexyl)-1-(3,4-difluorophenyl)ethane..Iaddend..Iadd.24. A compound of formula (9) ##STR19## wherein R is an alkyl, alkoxy, alkenyl or alkanoyloxy group which has in each case 1-12 C atoms in the alkyl moiety and which has a straight or branched and chiral or non-chiral chain,   X 2  and X 3  are independently hydrogen, halogen or nitrile, and   Halogen is fluorine or chlorine,   with the proviso that at least one of the groups X 2  and X 3  is not hydrogen..Iaddend..Iadd.25. A compound of claim 24, wherein R is alkyl of   
     
     
        1-12 C atoms..Iaddend..Iadd.26.  A compound of claim 24, wherein X 2  and X 3  are H, F or Cl..Iaddend..Iadd.27. A compound of claim 24, wherein one of X 2  and X 3  is F and the other is H..Iaddend..Iadd.28. A compound of claim 24, wherein X 2  is H, X 3  is F and Halogen is F..Iaddend..Iadd.29. A compound of claim 27, wherein halogen is Cl..Iaddend..Iadd.30. A compound of claim 24, which is 2-(4-trans-methylcyclohexyl)-1-(4-chloro-2-fluorophenyl)ethane   2-(4-trans-ethylcyclohexyl)-1-(4-chloro-2-fluorophenyl)ethane   2-(4-trans-propylcyclohexyl)-1-(4-chloro-2-fluorophenyl)ethane   2-(4-trans-butylcyclohexyl)-1-(4-chloro-2-fluorophenyl)ethane   2-(4-trans-pentylcyclohexyl)-1-(4-chloro-2-fluorophenyl)ethane   2-(4-trans-hexylcyclohexyl)-1-(4-chloro-2-fluorophenyl)ethane   2-(4-trans-heptylcyclohexyl)-1-(4-chloro-2-fluorophenyl)ethane   2-(4-trans-octylcyclohexyl)-1-(4-chloro-2-fluorophenyl)ethane   2-(4-trans-methylcyclohexyl)-1-(4-chloro-3-fluorophenyl)ethane   2-(4-trans-ethylcyclohexyl)-1-(4-chloro-3-fluorophenyl)ethane   2-(4-trans-propylcyclohexyl)-1-(4-chloro-3-fluorophenyl)ethane   2-(4-trans-butylcyclohexyl)-1-(4-chloro-3-fluorophenyl)ethane   2-(4-trans-pentylcyclohexyl)-1-(4-chloro-3-fluorophenyl)ethane   2-(4-trans-hexylcyclohexyl)-1-(4-chloro-3-fluorophenyl)ethane   2-(4-trans-heptylcyclohexyl)-1-(4-chloro-3-fluorophenyl)ethane   2-(4-trans-octylcyclohexyl)-1-(4-chloro-3-fluorophenyl)ethane   2-(4-trans-methylcyclohexyl)-1-(2,4-difluorophenyl)ethane   2-(4-trans-ethylcyclohexyl)-1-(2,4-difluorophenyl)ethane   2-(4-trans-propylcyclohexyl)-1-(2,4-difluorophenyl)ethane   2-(4-trans-butylcyclohexyl)-1-(2,4-difluorophenyl)ethane   2-(4-trans-pentylcyclohexyl)-1-(2,4-diflurophenyl)ethane   2-(4-trans-hexylcyclohexyl)-1-(2,4-difluorophenyl)ethane   2-(4-trans-heptylcyclohexyl)-1-(2,4-difluorophenyl)ethane   2-(4-trans-methylcyclohexyl)-1-(3,4-difluorophenyl)ethane   2-(4-trans-ethylcyclohexyl)-1-(3,4-difluorophenyl)ethane   2-(4-trans-propylcyclohexyl)-1-(3,4-difluorophenyl)ethane   2-(4-trans-butylcyclohexyl)-1-(3,4-difluorophenyl)ethane   2-(4-trans-pentylcyclohexyl)-1-(3,4-difluorophenyl)ethane   2-(4-trans-hexylcyclohexyl)-1-(3,4-difluorophenyl)ethane, or   2-(4-trans-heptylcyclohexyl)-1-(3,4-difluorophenyl)ethane..Iaddend..Iadd.31. A compound of formula (2) ##STR20## wherein R is an alkyl, alkoxy, alkenyl or alkanoyloxy group which has in each case 1-12 C atoms in the alkyl moiety and which has a straight or branched and chiral or non-chiral chain,   X 2  and X 3  are independently hydrogen, halogen or nitrile, and   Halogen is fluorine or chlorine,   with the proviso that at least one of the groups X 2  and X 3  is not hydrogen..Iaddend..Iadd.32. A compound of claim 31, wherein X 2  and X 3  are H, F or Cl..Iaddend..Iadd.33. A compound of claim 31, wherein one of X 2  and X 3  is F and the other is H..Iaddend..Iadd.34. A compound of claim 31, which is   2-(4-[trans-4-heptylcyclohexyl]phenyl)-1-(4-chloro-2-fluorophenyl)ethane, or   2-(4-[trans-4-pentylcyclohexyl]phenyl)-1-(4-chloro-2-fluorophenyl)ethane..Iaddend..Iadd.35. In a liquid crystal mixture having at least two liquid crystal components, the improvement wherein at least one such component is a compound of claim 17..Iaddend..Iadd.36. In a liquid crystal mixture having at least two liquid crystal components, the improvement wherein at least one such component is a compound of claim 24..Iaddend..Iadd.37. In a liquid crystal mixture having at least two liquid crystal components, the improvement wherein at least one such component is a compound of claim 31..Iaddend..Iadd.38. A compound of claim 31, wherein R is alkyl of 1-11 C atoms..Iaddend..Iadd.39. A compound of claim 31, wherein R is alkoxy or   
     
     
        alkanoyloxy of 1-12 C atoms..Iaddend..Iadd.40.  A compound of claim 31, wherein R is alkoxy, alkenyl or alkanoyloxy of 1-12 C atoms..Iaddend..Iadd.41. A compound of claim 31, wherein halogen is fluorine..Iaddend..Iadd.42. A compound of claim 31, wherein halogen is chlorine..Iaddend..Iadd.43. A compound of claim 17, wherein R is alkyl of 1-11 C atoms..Iaddend..Iadd.44. A compound of claim 17, wherein R is alkoxy or alkanoyloxy of 1-12 C atoms..Iaddend..Iadd.45. A compound of claim 17, wherein R is alkoxy, alkenyl or alkanoyloxy of 1-12 C atoms..Iaddend..Iadd.46. A compound of claim 17, wherein R is alkyl, alkoxy or alkanoyloxy which has 1-12 C atoms in each case in the alkyl moiety..Iaddend..Iadd.47. A compound of claim 24, wherein R is alkyl, alkoxy or alkanoyloxy which has 1-12 C atoms in each case in the alkyl moiety..Iaddend..Iadd.48. A compound of claim 31, wherein R is alkyl, alkoxy or alkanoyloxy which has 1-12 C atoms in each case in the alkyl moiety..Iaddend..Iadd.49. A compound of claim 17, wherein R is alkenyl which has 1-12 C atoms in each case in the alkyl moiety..Iaddend..Iadd.50. A compound of claim 24, wherein R is alkenyl which has 1-12 C atoms in each case in the alkyl moiety..Iaddend..Iadd.51. A compound of claim 31, wherein R is alkenyl which has 1-12 C atoms in each case in the alkyl 
     
     
        moiety..Iaddend..Iadd.52.  A compound of claim 21, wherein R is alkyl..Iaddend..Iadd.53. A compound of claim 52 which is 2-(trans-4-methyl-4'-bicyclohexyl)-1-(2,4-difluorophenyl)-ethane   2-(trans-4-ethyl-4'-bicyclohexyl)-1-(2,4-difluorophenyl)-ethane   2-(trans-4-propyl-4'-bicyclohexyl)-1-(2,4-difluorophenyl)-ethane   2-(trans-4-butyl-4'-bicyclohexyl)-1-(2,4-difluorophenyl)-ethane   2-(trans-4-pentyl-4'-bicyclohexyl)-1-(2,4-difluorophenyl)-ethane   2-(trans-4-hexyl-4'-bicyclohexyl)-1-(2,4-difluorophenyl)-ethane   2-(trans-4-heptyl-4'-bicyclohexyl)-1-(2,4-difluorophenyl)-ethane   2-(trans-4-methyl-4'-bicyclohexyl)-1-(3,4-difluorophenyl)-ethane   2-(trans-4-ethyl-4'-bicyclohexyl)-1-(3,4-difluorophenyl)-ethane   2-(trans-4-propyl-4'-bicyclohexyl)-1-(3,4-difluorophenyl)-ethane   2-(trans-4-butyl-4'-bicyclohexyl)-1-(3,4-difluorophenyl)-ethane   2-(trans-4-pentyl-4'-bicyclohexyl)-1-(3,4-difluorophenyl)-ethane   2-(trans-4-hexyl-4'-bicyclohexyl)-1-(3,4-difluorophenyl)-ethane, or   2-(trans-4-heptyl-4'-bicyclohexyl)-1-(3,4-difluorophenyl)-ethane..Iaddend..Iadd.54. A compound of claim 28, wherein R is alkyl..Iaddend..Iadd.55. A compound of claim 54 which is   2-(4-trans-methylcyclohexyl)-1-(2,4-difluorophenyl)-ethane   2-(4-trans-ethylcyclohexyl)-1-(2,4-difluorophenyl)-ethane   2-(4-trans-propylcyclohexyl)-1-(2,4-difluorophenyl)-ethane   2-(4-trans-butylcyclohexyl)-1-(2,4-difluorophenyl)-ethane   2-(4-trans-pentylcyclohexyl)-1-(2,4-difluorophenyl)-ethane   2-(4-trans-hexylcyclohexyl)-1-(2,4-difluorophenyl)-ethane   2-(4-trans-heptylcyclohexyl)-1-(2,4-difluorophenyl)-ethane   2-(4-trans-methylcyclohexyl)-1-(3,4-difluorophenyl)-ethane   2-(4-trans-ethylcyclohexyl)-1-(3,4-difluorophenyl)-ethane   2-(4-trans-propylcyclohexyl)-1-(3,4-difluorophenyl)-ethane   2-(4-trans-butylcyclohexyl)-1-(3,4-difluorophenyl)-ethane   2-(4-trans-pentylcyclohexyl)-1-(3,4-difluorophenyl)-ethane   2-(4-trans-hexylcyclohexyl)-1-(3,4-difluorophenyl)-ethane, or   2-(4-trans-heptylcyclohexyl)-1-(3,4-difluorophenyl)-ethane..Iaddend..Iadd.56. A compound according to claim 7, wherein X 3  is fluorine or chlorine..Iaddend.