Compound, liquid-crystal composition, and radio frequency phase shifter

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

where R 1 denotes a hydrogen atom or a C1 to C20 linear or C3 to C20 branched or cyclic alkyl group, the alkyl group optionally having any hydrogen atom therein replaced with a halogen atom and optionally having one —CH 2 —therein, or each of two or more independently, replaced with —O—, —S—, —CO—, —CS—, —COO—, —OCO—, —CO—S—, —S—CO—, —O—CO—O—, —CO—NH—, —NH—CO—, —CH═CH—, —CF═CF—, or —C≡C—, with the proviso that no oxygen atoms are bound directly to one another;

R 2 denotes a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a pentafluorosulfanyl group, a nitro group, a cyano group, an isocyano group, an amino group, a hydroxyl group, a mercapto group, a methylamino group, a dimethylamino group, a diethylamino group, a diisopropylamino group, a trimethylsilyl group, a dimethylsilyl group, or a C1 to C20 linear or C3 to C20 branched or cyclic alkyl group optionally having one —CH 2 —therein, or each of two or more independently, replaced with —O—, —S—, —CO—, —CS—, —COO—, —OCO—, —CO—S—, —S—CO—, —O—CO—O—, —CO—NH—, —NH—CO—, —CH═CH—COO—, —CH═CH—OCO—, —COO—CH═CH—, —OCO—CH═CH—, —CH═CH—, —CF═CF—, or —C≡C—, with the proviso that no oxygen atoms are bound directly to one another, the alkyl group optionally having any hydrogen atom therein replaced with a fluorine atom;

A 1 and A 2 each independently denote a substituted or unsubstituted C3 to C16 hydrocarbon ring or heterocycle, and a plurality of A 2 s may be the same or different;

L 1 and L 2 each independently denote a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a pentafluorosulfanyl group, a nitro group, a cyano group, an isocyano group, an amino group, a hydroxyl group, a mercapto group, a methylamino group, a dimethylamino group, a diethylamino group, a diisopropylamino group, a trimethylsilyl group, a dimethylsilyl group, a thioisocyano group, or a C1 to C20 linear or C3 to C20 branched or cyclic alkyl group optionally having one —CH 2 — therein, or each of two or more independently, replaced with —O—, —S—, —CO—, —CS—, —COO—, —OCO—, —CO—S—, —S—CO—, —O—CO—O—, —CO—NH—, —NH—CO—, —CH═CH—COO—, —CH═CH—OCO—, —COO—CH═CH—, —OCO—CH═CH—, —CH═CH—, —CF≡CF—, or with the proviso that no oxygen atoms are bound directly to one another, the alkyl group optionally having any hydrogen atom therein replaced with a fluorine atom;

Z 1 on each occurrence independently denotes a single bond, —CH═CH or —C≡, a plurality of Z 1 s may be the same or different, and at least one of the Z 1 s, or the Z 1 if there is only one Z 1 , denotes C≡C—; and

n1 denotes an integer of 1 to 3.

2. The compound according to claim 1 , wherein:

in general formula (I), A 1 and A 2 each independently denote a group selected from the group consisting of:

(a) a 1,4-cyclohexylene group optionally having one —CH 2 —or two or more nonadjacent —CH 2 —s therein replaced with —O— or —S—;

(b) a 1,4-phenylene group optionally having one —CH═ or two or more nonadjacent —CH═s therein replaced with —N═;

(c) a 1,4-cyclohexenylene, bicyclo[2.2.2]octane-1,4-diyl, naphthalene-2,6-diyl, naphthalene-1,4-diyl, 1,2,3,4-tetrahydronaphthalene-2,6-diyl, 5,6,7,8-tetrahydronaphthalene-1,4-diyl, decahydronaphthalene-2,6-diyl, anthracene-2,6-diyl, anthracene-1,4-diyl, anthracene-9,10-diyl, or phenanthrene-2,7-diyl group optionally having at least one hydrogen atom therein replaced with a fluorine or chlorine atom, the naphthalene-2,6-diyl, naphthalene-1,4-diyl, 1,2,3,4-tetrahydronaphthalene-2,6-diyl, 5,6,7,8-tetrahydronaphthalene- 1,4-diyl, anthracene-2,6-diyl, anthracene- 1,4-diyl, anthracene-9,10-diyl, or phenanthrene-2,7-diyl group optionally having one —CH— or two or more —CH=s therein replaced with —N═; and

(d) a thiophene-2,5-diyl, benzothiophene-2,5-diyl, benzothiophene-2,6-diyl, dibenzothiophene-3,7-diyl, dibenzothiophene-2,6-diyl, or thieno [3,2-b]thiophene-2,5-diyl group optionally having one —CH═ or two or more nonadjacent —CH=s therein replaced with —N═, unsubstituted or substituted with one or more substituents L 3 , and a plurality of A 2 s may be the same or different;

L 3 on each occurrence independently denotes a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a pentafluorosulfanyl group, a nitro group, a cyano group, an isocyano group, an amino group, a hydroxyl group, a mercapto group, a methylamino group, a dimethylamino group, a diethylamino group, a diisopropylamino group, a trimethylsilyl group, a dimethylsilyl group, a thioisocyano group, or a C1 to C20 linear or C3 to C20 branched or cyclic alkyl group optionally having one —CH 2 — therein, or each of two or more independently, replaced with —O—, —S—, —CO—, —CS—, —COO—, —OCO—, —CO—S—, —S—CO—, —O—CO—O—, —CO—NH—, —NH—CO—, —CH═CH—COO—, —CH═CH—OCO—, —COO—CH═CH—, —OCO—CH═CH—, —CH═CH—, —CF═CF—, or —CC—, with the proviso that no oxygen atoms are bound directly to one another, the alkyl group optionally having any hydrogen atom therein replaced with a fluorine atom.

3. The compound according to claim 1 , wherein:

general formula (I) is represented by general formula (I-i):

where R 11 on each occurrence independently denotes a hydrogen atom or a C1 to C20 linear or C3 to C20 branched alkyl group, the alkyl group optionally having any hydrogen atom therein replaced with a halogen atom and optionally having one —CH 2 —therein, or each of two or more independently, replaced with —O—, —S—, —CH═CH—, —CF═CF—, or —C≡C—;

R 21 denotes a fluorine atom, a chlorine atom, a nitro group, a cyano group, an isocyano group, or a C1 to C20 linear or C3 to C20 branched or cyclic alkyl group, the alkyl group optionally having any hydrogen atom therein replaced with a fluorine atom and optionally having one —CH 2 — therein, or each of two or more independently, replaced with —O—, —S—, —CH═CH—, —CF═CF—, or —C≡C—;

A 11 and A 21 each independently denote a 1,4-cyclohexylene, tetrahydropyrane-2,5-diyl, dioxane-2,5-diyl, 1,4-phenylene, naphthalene-2,6-diyl, naphthalene-1,4-diyl, 5,6,7,8-tetrahydronaphthalene-1,4-diyl, phenanthrene-2,7-diyl, benzothiophene-2,5-diyl, benzothiophene-2,6-diyl, benzothiazole-2,5-diyl, benzothiazole-2,6-diyl, dibenzothiophene-3,7-diyl, dibenzothiophene-2,6-diyl, or thieno[3,2-b]thiophene-2,5-diyl group, a plurality of A 21 s may be the same or different, and the groups A 11 and A 21 may be unsubstituted or substituted with one or more substituents L 31 ;

L 11 and L 21 each independently denote a hydrogen atom, a fluorine atom, a chlorine atom, or a C1 to C20 linear or C3 to C20 branched or cyclic alkyl group, the alkyl group optionally having any hydrogen atom therein replaced with a fluorine atom and optionally having one —CH 2 —therein, or each of two or more independently, replaced with —O—, —S—, —CF═CF—, or —C≡C—;

L 31 on each occurrence independently denotes a fluorine atom, a chlorine atom, or a C1 to C20 linear or C3 to C20 branched or cyclic alkyl group, the alkyl group optionally having any hydrogen atom therein replaced with a fluorine atom and optionally having one —CH 2 — therein, or each of two or more independently, replaced with —O—, —S—, —CH═CH—, —CF═CF—, and a plurality of L 31 s may be the same or different;

Z 11 on each occurrence independently denotes a single bond or —C≡C—, a plurality of Z 11 s may be the same or different, and at least one of the Z 11 s, or the Z 11 if there is only one Z 11 , denotes C≡C—; and

n11 denotes an integer of 1 to 3.

4. The compound according to claim 1 , wherein:

general formula (I) is represented by general formula (I-ii):

where R 12 denotes a C1 to C12 linear or C3 to C12 branched alkyl group, the alkyl group optionally having any hydrogen atom therein replaced with a fluorine atom and optionally having one —CH 2 — therein, or each of two or more independently, replaced with —O—, —CH═CH—, or —C≡—;

R 22 denotes a fluorine atom, a cyano group, or a C 1 to C10 linear or C3 to C10 branched or cyclic alkyl group, the alkyl group optionally having any hydrogen atom therein replaced with a fluorine atom and optionally having at least one —CH 2 — therein replaced with —O—;

A l2 and A 22 each independently denote a group selected from formulae (A-ii-1) to (A-ii-17), and a plurality of A 22 s may be the same or different:

where broken lines represent binding sites, and a plurality of L 32 s and L 42 s may be the same or different;

L 12 , L 22 , L 32 , and L 42 each independently denote a hydrogen atom, a flourine atom, or a C1 to C10 linear or C3 to C1 0 branched or cyclic alkyl group, the alkyl group optionally having any hydrogen atom therein replaced with a fluorine atom and optionally having at least one —CH 2 — therein replaced with —O—;

Z 12 on each occurrence independently denotes —C≡C; and

n12 denotes an integer of 1 to 3.

5. A composition comprising the compound according to claim 1 .

6. A liquid-crystal composition comprising the compound according to claim 1 .

7. The liquid-crystal composition according to claim 6 , wherein the composition has a refractive-index anisotropy of 0.15 or more.

8. The liquid-crystal composition according to claim 6 , wherein the composition has a dielectric anisotropy of 2 or more.

9. The liquid-crystal composition according to claim 6 , wherein the composition has a dielectric anisotropy of 2 or less.

10. A radio frequency phase shifter, a phased-array antenna, an image recognition device, a distance meter, a liquid-crystal display, a liquid-crystal lens, or a birefringent lens for 3D image display comprising the liquid-crystal composition according to claim 6 .