Piperidine derivative, liquid crystal composition and liquid crystal display device

1. A compound, represented by formula (1):

wherein, in formula (1),

R 1 , R 2 , R 3 and R 4 are independently hydrogen or alkyl having 1 to 4 carbons;

ring A 1 and ring A 2 are independently 1,4-cyclohexylene, 1,4-cyclohexenylene, 1,2-phenylene, 1,3-phenylene, 1,4-phenylene, naphthalene-1,3-diyl, naphthalene-1,4-diyl, naphthalene-1,5-diyl, naphthalene-1,6-diyl, naphthalene-1,7-diyl, naphthalene-1,8-diyl, naphthalene-2,3-diyl, naphthalene-2,6-diyl, naphthalene-2,7-diyl, decahydronaphthalene-2,6-diyl, dihydropyrane-2,5-diyl, tetrahydropyran-2,5-diyl, 1,3-dioxane-2,5-diyl, pyrimidine-2,5-diyl or pyridine-2,5-diyl, and in the rings, at least one piece of hydrogen may be replaced by halogen, alkyl having 1 to 5 carbons, alkoxy having 1 to 5 carbons, or alkyl having 1 to 5 carbons in which at least one piece of hydrogen is replaced by halogen;

Z 1 and Z 3 are independently a single bond, —O—, or alkylene having 2 to 10 carbons, and in the alkylene, at least one —CH 2 — may be replaced by —O—, at least one —CH 2 —CH 2 — may be replaced by —CH═CH— or —CH≡CH—, and at least one hydrogen may be replaced by fluorine,

Z 2 is a single bond, or alkylene having 1 to 10 carbons, and in the alkylene, at least one —CH 2 — may be replaced by —O—, at least one —CH 2 —CH 2 — may be replaced by —CH═CH— or —CH≡CH—, and at least one hydrogen may be replaced by fluorine; and

n is 0, 1 or 2.

2. The compound according to claim 1 , wherein, in formula (1) described in claim 1 ,

R 1 , R 2 , R 3 and R 4 are independently hydrogen or alkyl having 1 to 4 carbons;

ring A 1 and ring A 2 are independently 1,4-cyclohexylene, 1,4-cyclohexenylene, 1,4-phenylene, 1,4-phenylene in which at least one hydrogen is replaced by fluorine, tetrahydropyran-2,5-diyl, pyridine-2,5-diyl, 1,3-dioxane-2,5-diyl, naphthalene-2,6-diyl, naphthalene-2,6-diyl in which at least one hydrogen is replaced by fluorine, or decahydronaphthalene-2,6-diyl;

Z 1 and Z 3 are independently a single bond, —O—, or alkylene having 2 to 10 carbons, and in the alkylene, at least one —CH 2 — may be replaced by —O— and at least one —CH 2 —CH 2 — may be replaced by —CH═CH—,

Z 2 is a single bond, or alkylene having 1 to 10 carbons, and in the alkylene, at least one —CH 2 — may be replaced by —O—, at least one —CH 2 —CH 2 — may be replaced by —CH═CH—; and

n is 0, 1 or 2.

3. The compound according to claim 1 , wherein, in formula (1) described in claim 1 ,

R 1 , R 2 , R 3 and R 4 are independently alkyl having 1 to 4 carbons;

ring A 1 and ring A 2 are independently 1,4-cyclohexylene, 1,4-cyclohexenylene, 1,4-phenylene, 1,4-phenylene in which at least one hydrogen is replaced by fluorine, naphthalene-2,6-diyl, or naphthalene-2,6-diyl in which at least one hydrogen is replaced by fluorine;

Z 1 and Z 3 are independently a single bond, —O—, or alkylene having 2 to 10 carbons, and in the alkylene, at least one —CH 2 — may be replaced by —O— and at least one —CH 2 —CH 2 — may be replaced by —CH═CH—,

Z 2 is a single bond, or alkylene having 1 to 10 carbons, and in the alkylene, at least one —CH 2 — may be replaced by —O—, at least on —CH 2 —CH 2 — may be replaced by —CH═CH—; and

n is 0, 1 or 2.

4. The compound according to claim 1 , wherein, in formula (1) described in claim 1 ,

R 1 , R 2 , R 3 and R 4 are methyl;

ring A 1 and ring A 2 are independently 1,4-cyclohexylene, 1,4-phenylene, or 1,4-phenylene in which at least one-hydrogen is replaced by fluorine;

Z 1 and Z 3 are single bonds, and Z 2 is a single bond, —CH 2 —, —CH 2 CH 2 —, —CH═CH—, —OCH 2 — or —CH 2 O—; and

n is 0 or 1.

5. The compound according to claim 1 , wherein, in formula (1) described in claim 1 ,

R 1 , R 2 , R 3 and R 4 are methyl;

ring A 1 and ring A 2 are independently 1,4-phenylene or 2-fluoro-1,4-phenylene;

Z 1 , Z 2 and Z 3 are single bonds; and

n is 0 or 1.

6. A liquid crystal composition, containing at least one compound according to claim 1 .

7. The liquid crystal composition according to claim 6 , further containing at least one compound selected from the group of compounds represented by formulas (2) to (4):

wherein, in formulas (2) to (4),

R 11 and R 12 are independently alkyl having 1 to 10 carbons or alkenyl having 2 to 10 carbons, and in the alkyl or the alkenyl, at least one —CH 2 — may be replaced by —O—, and at least one hydrogen may be replaced by fluorine;

ring B 1 , ring B 2 , ring B 3 and ring B 4 are independently 1,4-cyclohexylene, 1,4-phenylene, 2-fluoro-1,4-phenylene, 2,5-difluoro-1,4-phenylene or pyrimidine-2,5-diyl; and

Z 11 , Z 12 and Z 13 are independently a single bond, —CH 2 CH 2 —, —CH═CH—, —C≡C— or —COO—.

8. The liquid crystal composition according to claim 6 , further containing at least one compound selected from the group of compounds represented by formulas (5) to (7):

wherein, in formulas (5) to (7),

R 13 is alkyl having 1 to 10 carbons or alkenyl having 2 to 10 carbons, and in the alkyl and the alkenyl, at least one —CH 2 — may be replaced by —O—, and at least one hydrogen may be replaced by fluorine;

X 11 is fluorine, chlorine, —OCF 3 , —OCHF 2 , —CF 3 , —CHF 2 , —CH 2 F, —OCF 2 CHF 2 or —OCF 2 CHFCF 3 ;

ring C 1 , C 2 and C 3 are independently 1,4-cyclohexylene, 1,4-phenylene in which at least one hydrogen may be replaced by fluorine, tetrahydropyran-2,5-diyl, 1,3-dioxane-2,5-diyl or pyrimidine-2,5-diyl;

Z 14 , Z 15 and Z 16 are independently a single bond, —CH 2 CH 2 —, —CH═CH—, —C≡C—, —COO—, —CF 2 O—, —OCF 2 —, —CH 2 O— or —(CH 2 ) 4 —; and

L 11 and L 12 are independently hydrogen or fluorine.

9. The liquid crystal composition according to claim 6 , further containing at least one compound selected from the group of compounds represented by formula (8):

wherein, in formula (8),

R 14 is alkyl having 1 to 10 carbons or alkenyl having 2 to 10 carbons, and in the alkyl and the alkenyl, at least one —CH 2 — may be replaced by —O—, and at least one hydrogen may be replaced by fluorine;

X 12 is —C≡N or —C≡C—C≡N;

ring D 1 is 1,4-cyclohexylene, 1,4-phenylene in which at least one hydrogen may be replaced by fluorine, tetrahydropyran-2,5-diyl, 1,3-dioxane-2,5-diyl or pyrimidine-2,5-diyl;

Z 17 is a single bond, —CH 2 CH 2 —, —C≡C—, —COO—, —CF 2 O—, —OCF 2 — or —CH 2 O—;

L 13 and L 14 are independently hydrogen or fluorine; and

i is 1, 2, 3 or 4.

10. The liquid crystal composition according to claim 6 , further containing at least one of a polymerizable compound, a polymerization initiator, a polymerization inhibitor, an optically active compound, an antioxidant, an ultraviolet light absorber, a light stabilizer, a heat stabilizer and an antifoaming agent.

11. A liquid crystal display device, including at least one liquid crystal composition according to claim 6 .