Organic ionic phenylpyrimidine compounds and displays formed thereof
View Patent ↗Ionic mesogenic compounds of formula (I) can be used to form liquid crystal displays, such as ferroelectric liquid crystal displays, having enhanced anti-image sticking properties. The mesogenic compounds may contain a cationic group such as an ammonium or phosphonium group bonded to an alkyl chain that is terminally bonded to a para-substituted pyrimidyl benzene moiety. The counterion can be an organic or inorganic anion. The compounds can be used either as dopants in art ferroelectric liquid crystal compositions to reduce image sticking, or can be used as the primary or predominant component of a liquid crystal display system. Additional compounds, devices, and methods are disclosed.
1. A mesogenic compound for a liquid crystal display, wherein the compound is of formula (I)
Wherein
R is a linear (C 6 -C 16 )alkyl, (C 6 -C 16 )fluoroalkyl, (C 6 -C 16 )alkoxy, (C 6 -C 16 )fluoroalkoxy, or a (C 6 -C 16 )alkyl-S(O) q group wherein q=0, 1 or 2;
AR is a group of formula
wherein a first wavy line indicates a point of attachment to R and a second wavy line indicates a point of attachment to Z;
n is 2 to 12;
R 1 , R 2 , and R 3 are each independently (C 1 -C 16 ) alkyl or fluoroalkyl;
Y is N or P;
Z is O, S(O) q , or CH 2 wherein q is 0, 1, or 2; and
X is an anion.
2. The compound of formula (I) of claim 1 wherein AR is
3. The compound of formula (I) of claim 1 wherein AR is
4. The compound of formula (I) claim 1 wherein X is a halide, a boride, an alkylsulfonate, a fluoroalkylsulfonate, a carboxylate, a phosphinate, perchlorate, or PF 6 —.
5. The compound of formula (I) of claim 4 wherein the halide is chloride or iodide; or the boride is BF 4 − , n-BuBF 3 − , or 3,3-dimethylbutylBF 3 − ; or the alkylsulfonate is butylsulfonate or octylsulfonate; or the fluoroalkylsulfonate is perfluorobutylsulfonate or perfluorooctylsulfonoate; or the carboxylate is trifluoroacetate; or the phosphinate is bis-(2,4,4-trimethylpentyl)phosphinate.
6. The compound of formula (I) of claim 1 wherein Y is N.
7. The compound of formula (I) of claim 1 wherein R is a linear (C 8 -C 12 )alkyl group.
8. The compound of formula (I) of claim 7 wherein R is n-C 8 H 17 , n-C 10 H 21 , or n-C 12 H 25 .
9. The compound of formula (I) of claim 1 wherein R is a partially or completely fluorinated linear (C 8 -C 12 )alkyl group.
10. The compound of formula (I) of claim 9 wherein R is a CF 3 CF 2 CF 2 CF 2 CH 2 CH 2 CH 2 CH 2 group.
11. The compound of formula (I) of claim 1 wherein R is a (C 6 -C 16 )alkoxy or a (C 6 -C 16 ) fluoroalkoxy group.
12. The compound of formula (I) of claim 1 wherein Z is O.
13. The compound of formula (I) of claim 1 wherein R 1 , R 2 , and R 3 are each independently selected from the set consisting of ethyl, n-butyl, n-pentyl, n-hexyl, n-octyl, n-decyl, and n-dodecyl group.
14. The compound of formula (I) of claim 12 wherein R 1 , R 2 , and R 3 are all an identical alkyl selected from the set consisting of ethyl, n-butyl, n-pentyl, n-hexyl, n-octyl, n-decyl, and n-dodecyl group.
15. The compound of formula (I) of claim 1 wherein the compound is any of the following:
16. A liquid crystal composition comprising a compound of formula (I) A liquid crystal comprising a compound of formula (I)
Wherein
R is a linear (C 6 -C 16 )alkyl, (C 6 -C 16 )fluoroalkyl, (C 6 -C 16 )alkoxy, (C 6 -C 16 )fluoroalkoxy, or a (C 6 -C 16 )alkyl-S(O) q group wherein q=0, 1 or 2;
AR is a group of formula
wherein a first wavy line indicates a point of attachment to R and a second wavy line indicates a point of attachment to Z;
n is 2 to 12;
R 1 , R 2 , and R 3 are each independently (C 1 -C 16 ) alkyl or fluoroalkyl;
Y is N or P;
Z is O, S(O) q , or CH 2 wherein q is 0, 1, or 2; and
X is an anion.
17. The liquid crystal of claim 16 wherein AR is
18. The liquid crystal of claim 16 wherein AR is
19. The liquid crystal of claim 16 wherein X is a halide, a boride, an alkylsulfonate, a fluoroalkylsulfonate, a carboxylate, a phosphinate, perchlorate, or PF 6 —.
20. The liquid crystal of claim 19 wherein the halide is chloride or iodide; or the boride is BF 4 − , n-BuBF 3 − , or 3,3-dimethylbutylBF 3 − ; or the alkylsulfonate is butylsulfonate or octylsulfonate; or the fluoroalkylsulfonate is perfluorobutylsulfonate or perfluorooctylsulfonoate; or the carboxylate is trifluoroacetate; or the phosphinate is bis-(2,4,4-trimethylpentyl)phosphinate.
21. The liquid crystal of claim 16 wherein Y is N.
22. The liquid crystal of claim 16 wherein R is a linear (C 8 -C 12 )alkyl group.
23. The liquid crystal of claim 16 wherein R is n-C 8 H 17 , n-C 10 H 21 , or n-C 12 H 25 .
24. The liquid crystal of claim 16 wherein R is a partially or completely fluorinated linear (C 8 -C 12 )alkyl group.
25. The liquid crystal of claim 24 wherein R is a CF 3 CF 2 CF 2 CF 2 CH 2 CH 2 CH 2 CH 2 group.
26. The liquid crystal of claim 16 wherein R is a (C 6 -C 16 )alkoxy or a (C 6 -C 16 )fluoroalkoxy group.
27. The liquid crystal of claim 16 wherein Z is O.
28. The liquid crystal of claim 16 wherein R 1 , R 2 , and R 3 are each independently selected from the set consisting of ethyl, n-butyl, n-pentyl, n-hexyl, n-octyl, n-decyl, and n-dodecyl.
29. The liquid crystal of claim 16 wherein R 1 , R 2 , and R 3 are all an identical alkyl selected from the set consisting of ethyl, n-butyl, n-pentyl, n-hexyl, n-octyl, n-decyl, and n-dodecyl.
30. The liquid crystal of claim 16 wherein the compound of formula (I) is any of the following:
31. The liquid crystal of claim 16 wherein the liquid crystal is a ferroelectric liquid crystal.
32. A display device comprising the compound of claim 1 or the liquid crystal of claim 16 .
33. The display device of claim 32 comprising a ferroelectric liquid crystal composition.
34. A method of preparing a liquid crystal display device on silicon comprising incorporating the liquid crystal composition of claim 16 into a liquid crystal display on silicon by disposing the liquid crystal composition, onto a silicon surface.
35. The method of claim 34 wherein the liquid crystal display device is a ferroelectric liquid crystal display device.
36. A method of preparing a compound of formula (I) of claim 1 , comprising
a) first, contacting a compound of formula R-AR-OH and a compound of formula Br—(CH 2 ) n —Br, wherein R, AR, and n are as defined in claim 1 , in a dipolar organic solvent in the presence of a base to provide a compound of formula R-AR-O—(CH 2 ) n —Br;
b) next, contacting the compound of formula R-AR-O—(CH 2 ) n —Br and NaI in acetone solution to provide a compound of formula R-AR-O—(CH 2 ) n —I; and,
c) next, contacting the compound of formula R-AR-O—(CH 2 ) n —I and YR 1 R 2 R 3 , wherein Y, R 1 , R 2 , and R 3 are as defined in claim 1 , to provide a compound of formula (I).
37. The method of claim 36 wherein AR is a group of formula
wherein a first wavy line indicates a point of attachment to R and a second wavy line indicates a point of attachment to Z.
38. The method of claim 36 wherein the dipolar aprotic solvent is DMF.
39. The method of claim 36 wherein the base is CsCO 3 .
40. The method of claim 36 wherein Y is N.
41. The method of claim 36 wherein R 1 , R 2 , and R 3 are each independently selected from the set consisting of ethyl, n-butyl, n-pentyl, n-hexyl, n-octyl, n-decyl, and n-dodecyl.
42. The method of claim 41 wherein R 1 , R 2 , and R 3 are all identical.
43. A method of preparing a liquid crystal display device on silicon comprising,
incorporating a compound of claim 1 into a liquid crystal display on silicon by disposing the compound in a liquid crystal onto a silicon surface.
44. The method of claim 34 wherein the liquid crystal display device is a ferroelectric liquid crystal display device.
45. The display device of claim 32 comprising a ferroelectric liquid crystal composition.