Monofluorinated terphenyl compound having alkenyl, liquid crystal composition, and liquid crystal display device

1. A compound represented by formula (1):

wherein in formula (1), R 1 is hydrogen or alkyl having 1 to 5 carbons; one of X 1 and X 2 is hydrogen, and the other thereof is fluorine; and R 2 is hydrogen or methyl.

2. The compound according to claim 1 , wherein R 2 is hydrogen.

3. The compound according to claim 2 , wherein X 1 is fluorine, and X 2 is hydrogen.

4. A liquid crystal composition comprising at least one compound according to claim 1 .

5. The liquid crystal composition according to claim 4 , wherein the liquid crystal composition further comprises at least one compound selected from the group of compound represented by formulas (2), (3) and (4):

wherein in formulas (2) to (4), R 3 is independently alkyl having 1 to 10 carbons or alkenyl having 2 to 10 carbons, in the alkyl and alkenyl arbitrary hydrogen may be replaced by fluorine, and in the alkyl arbitrary —CH 2 — may be replaced by —O—;

X 3 is independently fluorine, chlorine, —OCF 3 , —OCHF 2 , —CF 3 , —CHF 2 , —CH 2 F, —OCF 2 CHF 2 or —OCF 2 CHFCF 3 ;

ring A and ring B are each independently 1,4-cyclohexylene, 1,3-dioxane-2,5-diyl or 1,4-phenylene in which arbitrary hydrogen may be replaced by fluorine; ring C is 1,4-cyclohexylene or 1,4-phenylene in which arbitrary hydrogen may be replaced by fluorine;

Z 1 and Z 2 are each independently —(CH 2 ) 2 —, —(CH 2 ) 4 —, —COO—, —CF 2 O—, —OCF 2 —, —CH═CH— or a single bond; and

L 1 and L 2 are each independently hydrogen or fluorine.

6. The liquid crystal composition according to claim 4 , wherein the liquid crystal composition further comprises at least one compound selected from the group of compound represented by formulas (5) and (6):

wherein in formulas (5) and (6), R 4 and R 5 are each independently alkyl having 1 to 10 carbons or alkenyl having 2 to 10 carbons, in the alkyl and alkenyl arbitrary hydrogen may be replaced by fluorine, and in the alkyl arbitrary —CH 2 — may be replaced by —O—;

X 4 is —C≡N or —C≡C—C≡N;

ring D is 1,4-cyclohexylene, 1,4-phenylene, 1,3-dioxane-2,5-diyl or pyrimidine-2,5-diyl;

ring E is 1,4-cyclohexylene, pyrimidine-2,5-diyl or 1,4-phenylene in which arbitrary hydrogen may be replaced by fluorine; ring F is 1,4-cyclohexylene or 1,4-phenylene;

Z 3 is —(CH 2 ) 2 —, —COO—, —CF 2 O—, —OCF 2 — or a single bond;

L 3 , L 4 and L 5 are each independently hydrogen or fluorine; and

a, b and c are each independently 0 or 1.

7. The liquid crystal composition according to claim 4 , wherein the liquid crystal composition further comprises at least one compound selected from the group of compound represented by formulas (7), (8), (9), (10) and (11):

wherein in formulas (7) to (11), R 6 is independently alkyl having 1 to 10 carbons or alkenyl having 2 to 10 carbons, in the alkyl and alkenyl arbitrary hydrogen may be replaced by fluorine, and in the alkyl arbitrary —CH 2 — may be replaced by —O—;

R 7 is independently fluorine, alkyl having 1 to 10 carbons or alkenyl having 2 to 10 carbons, in the alkyl and alkenyl arbitrary hydrogen may be replaced by fluorine, and in the alkyl arbitrary —CH 2 — may be replaced by —O—;

ring G and ring J are each independently 1,4-cyclohexylene, 1,4-phenylene or decahydro-2,6-naphthylene;

Z 4 and Z 5 are each independently —(CH 2 ) 2 —, —COO— or a single bond; and

L 6 , L 7 , L 8 and L 9 are each independently hydrogen or fluorine, provided that at least two of L 6 , L 7 , L 8 and L 9 are fluorine.

8. The liquid crystal composition according to claim 4 , wherein the liquid crystal composition further comprises at least one compound selected from the group of compound represented by formulas (12), (13) and (14):

wherein in formulas (12) to (14), R 8 and R 9 each independently alkyl having 1 to 10 carbons or alkenyl having 2 to 10 carbons, in the alkyl and alkenyl arbitrary hydrogen may be replaced by fluorine, and in the alkyl arbitrary —CH 2 — may be replaced by —O—;

ring L is independently 1,4-cyclohexylene, pyrimidine-2,5-diyl, 1,4-phenylene, 2-fluoro-1,4-phenylene, 3-fluoro-1,4-phenylene or 2,5-difluorophenylene;

ring K and ring M are each independently 1,4-cyclohexylene, pyrimidine-2,5-diyl, 1,4-phenylene or 2,5-difluorophenylene; and

Z 6 and Z 7 are each independently —C≡C—, —COO—, —(CH 2 ) 2 —, —CH═CH— or a single bond.

9. The liquid crystal composition according to claim 5 , wherein the liquid crystal composition further comprises at least one compound selected from the group of compound represented by formulas (5) and (6):

wherein in formulas (5) and (6), R 4 and R 5 are each independently alkyl having 1 to 10 carbons or alkenyl having 2 to 10 carbons, in the alkyl and alkenyl arbitrary hydrogen may be replaced by fluorine, and in the alkyl arbitrary —CH 2 — may be replaced by —O—;

X 4 is —C≡N or —C≡C—C≡N;

ring D is 1,4-cyclohexylene, 1,4-phenylene, 1,3-dioxane-2,5-diyl or pyrimidine-2,5-diyl;

ring E is 1,4-cyclohexylene, pyrimidine-2,5-diyl or 1,4-phenylene in which arbitrary hydrogen may be replaced by fluorine; ring F is 1,4-cyclohexylene or 1,4-phenylene;

Z 3 is —(CH 2 ) 2 —, —COO—, —CF 2 O—, —OCF 2 — or a single bond;

L 3 , L 4 and L 5 are each independently hydrogen or fluorine; and

a, b and c are each independently 0 or 1.

10. The liquid crystal composition according to claim 5 , wherein the liquid crystal composition further comprises at least one compound selected from the group of compound represented by formulas (12), (13) and (14):

wherein in formulas (12) to (14), R 8 and R 9 each independently alkyl having 1 to 10 carbons or alkenyl having 2 to 10 carbons, in the alkyl and alkenyl arbitrary hydrogen may be replaced by fluorine, and in the alkyl arbitrary —CH 2 — may be replaced by —O—;

ring L is independently 1,4-cyclohexylene, pyrimidine-2,5-diyl, 1,4-phenylene, 2-fluoro-1,4-phenylene, 3-fluoro-1,4-phenylene or 2,5-difluorophenylene;

ring K and ring M are each independently 1,4-cyclohexylene, pyrimidine-2,5-diyl, 1,4-phenylene or 2,5-difluorophenylene; and

Z 6 and Z 7 are each independently —COO—, —(CH 2 ) 2 —, —CH═CH— or a single bond.

11. The liquid crystal composition according to claim 6 , wherein the liquid crystal composition further comprises at least one compound selected from the group of compound represented by formulas (12), (13) and (14):

wherein in formulas (12) to (14), R 8 and R 9 each independently alkyl having 1 to 10 carbons or alkenyl having 2 to 10 carbons, in the alkyl and alkenyl arbitrary hydrogen may be replaced by fluorine, and in the alkyl arbitrary —CH 2 — may be replaced by —O—;

ring L is independently 1,4-cyclohexylene, pyrimidine-2,5-diyl, 1,4-phenylene, 2-fluoro-1,4-phenylene, 3-fluoro-1,4-phenylene or 2,5-difluorophenylene;

ring K and ring M are each independently 1,4-cyclohexylene, pyrimidine-2,5-diyl, 1,4-phenylene or 2,5-difluorophenylene; and

Z 6 and Z 7 are each independently —COO—, —(CH 2 ) 2 —, —CH═CH— or a single bond.

12. The liquid crystal composition according to claim 7 , wherein the liquid crystal composition further comprises at least one compound selected from the group of compound represented by formulas (12), (13) and (14):

wherein in formulas (12) to (14), R 8 and R 9 each independently alkyl having 1 to 10 carbons or alkenyl having 2 to 10 carbons, in the alkyl and alkenyl arbitrary hydrogen may be replaced by fluorine, and in the alkyl arbitrary —CH 2 — may be replaced by —O—;

ring L is independently 1,4-cyclohexylene, pyrimidine-2,5-diyl, 1,4-phenylene, 2-fluoro-1,4-phenylene, 3-fluoro-1,4-phenylene or 2,5-difluorophenylene;

ring K and ring M are each independently 1,4-cyclohexylene, pyrimidine-2,5-diyl, 1,4-phenylene or 2,5-difluorophenylene; and

Z 6 and Z 7 are each independently —C≡C—, —COO—, —(CH 2 ) 2 —, —CH═CH— or a single bond.

13. The liquid crystal composition according to claim 4 , wherein the liquid crystal composition further comprises an optically active compound.

14. A liquid crystal display device comprising the liquid crystal composition according to claim 4 .

15. The liquid crystal composition according to claim 5 , wherein the liquid crystal composition further comprises an optically active compound.

16. The liquid crystal composition according to claim 6 , wherein the liquid crystal composition further comprises an optically active compound.

17. The liquid crystal composition according to claim 7 , wherein the liquid crystal composition further comprises an optically active compound.

18. The liquid crystal composition according to claim 8 , wherein the liquid crystal composition further comprises an optically active compound.

19. The liquid crystal composition according to claim 9 , wherein the liquid crystal composition further comprises an optically active compound.

20. The liquid crystal composition according to claim 10 , wherein the liquid crystal composition further comprises an optically active compound.

21. The liquid crystal composition according to claim 11 , wherein the liquid crystal composition further comprises an optically active compound.

22. The liquid crystal composition according to claim 12 , wherein the liquid crystal composition further comprises an optically active compound.