JP2008088165A - Cyclohexene derivative having alkenyl group, liquid crystal composition and liquid crystal display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid crystal compound stable to heat, light, etc., taking a nematic phase over a wide temperature range, having a low viscosity, large optical anisotropy, moderate elastic constant K<SB>33</SB>and moderate negative dielectric anisotropy and exhibiting excellent compatibility with other liquid crystal compounds, and provide a liquid crystal composition containing the above compound, stable to heat, light, etc., and having a low viscosity, large optical anisotropy, moderate negative dielectric anisotropy, moderate elastic constant K<SB>33</SB>, low threshold voltage, high upper limit temperature of the nematic phase (phase-transition temperature between the nematic phase and an isotropic phase) and low lower-limit temperature of nematic phase. <P>SOLUTION: The invention provides a liquid crystal compound having a specific structure having an alkenyl and cyclohexenylene groups and a phenylene group having hydrogen atom on the benzene ring substituted with a fluorine atom, and provides a liquid crystal composition containing the compound. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a liquid crystal compound, a liquid crystal composition, and a liquid crystal display element. More specifically, the present invention relates to a difluorobenzene derivative having alkenyl and cyclohexenyl which are liquid crystal compounds, a liquid crystal composition having a nematic phase containing the compound, and a liquid crystal display device containing the composition.

  A liquid crystal display element typified by a liquid crystal display panel, a liquid crystal display module or the like is a liquid crystal compound (in the present invention, a compound having a liquid crystal phase such as a nematic phase or a smectic phase, and a component of a liquid crystal composition that does not have a liquid crystal phase. As an operation mode of the liquid crystal display element, including a PC (phase change) mode, a TN mode, and a TN mode. (Twisted nematic) mode, STN (super twisted nematic) mode, BTN (bistable twisted nematic) mode, ECB (electrically controlled birefringence) mode, OCB (optically compensated bend) mode, IPS (in-plane switching) mode, VA (vertical) Various modes such as an alignment mode are known.

  Among these operation modes, the ECB mode, IPS mode, VA mode, etc. are operation modes utilizing the vertical alignment of liquid crystal molecules, and in particular, the IPS mode and VA mode are conventional display modes such as TN mode, STN mode, etc. It is known that the narrow viewing angle, which is a drawback, can be improved.

  As a component of a liquid crystal composition having a negative dielectric anisotropy that can be used in liquid crystal display elements of these operation modes, many liquid crystal compounds in which hydrogen on the benzene ring is replaced with fluorine have been studied. (For example, refer to Patent Documents 1 to 8.)

For example, a compound (A) in which hydrogen on a benzene ring is replaced with fluorine has been studied (see Patent Document 1). However, this compound has a small optical anisotropy.
In addition, a compound (B) in which hydrogen on the benzene ring is replaced with fluorine and has alkenyl has been studied (see Patent Document 2). However, the optical anisotropy of this compound is not sufficiently large.

  Further, a compound (C) has been studied as a compound having hydrogen on the benzene ring replaced with fluorine and having cyclohexenylene and oxabicyclopentane (see Patent Document 3). However, such a compound has a very narrow mesophase range exhibiting liquid crystallinity and does not exhibit a high clearing point when formed into a composition.

  In addition, a compound (D) and a compound (E) having cyclohexenylene in which hydrogen on a benzene ring is replaced with fluorine have been reported (for example, see Patent Document 4 or 5). However, these have poor compatibility with other liquid crystal compounds in a low temperature range.

  Patent Document 6, Patent Document 7, and Patent Document 8 report compounds having cyclohexenylene in which hydrogen on the benzene ring is replaced with fluorine as an intermediate. However, these are used as raw materials or intermediates, and no compound having alkenyl and cyclohexenylene at the same time has been studied.

Japanese Patent Laid-Open No. 02-4725 JP 2000-53602 A Japanese Patent Laid-Open No. 10-237075 Japanese Patent Laid-Open No. 02-4723 JP 2002-193853 A International Publication No. 89/08633 Pamphlet International Publication No. 89/08687 Pamphlet EP1333301

  Even liquid crystal display elements in operation modes such as IPS mode and VA mode still have problems as display elements as compared with CRTs. For example, improvement in response speed, improvement in contrast, and reduction in drive voltage are desired. ing.

The display element operating in the above-described IPS mode or VA mode is mainly composed of a liquid crystal composition having a negative dielectric anisotropy. In order to further improve the above characteristics and the like, the above liquid crystal composition is used. It is necessary that the liquid crystalline compound contained in the product has the following properties (1) to (8). That is,
(1) being chemically stable and physically stable;
(2) having a high clearing point (liquid crystal phase-isotropic phase transition temperature);
(3) The lower limit temperature of the liquid crystal phase (nematic phase, smectic phase, etc.), especially the lower limit temperature of the nematic phase is low,
(4) low viscosity,
(5) having appropriate optical anisotropy;
(6) having an appropriate negative dielectric anisotropy;
(7) having an appropriate elastic constant K ₃₃ (K ₃₃ : bend elastic constant), and (8) excellent compatibility with other liquid crystal compounds,
It is.

When a composition containing a chemically and physically stable liquid crystal compound as in (1) is used for a display element, the voltage holding ratio can be increased.
Further, as in (2) and (3), a composition containing a liquid crystal compound having a high clearing point or a low lower limit temperature of the liquid crystal phase can expand the temperature range of the nematic phase, and in a wide temperature range. It can be used as a display element.

Furthermore, when a composition containing a compound having a low viscosity as in (4) or a compound having a large elastic constant K ₃₃ in (7) is used as a display element, the response speed can be improved, as in (5) In the case of a display element using a composition containing a compound having appropriate optical anisotropy, the contrast of the display element can be improved. Depending on the element design, the optical anisotropy needs to be small to large. Recently, methods for improving the response speed by reducing the cell thickness have been studied, and accordingly, a liquid crystal composition having a large optical anisotropy is also required.

In addition, when the liquid crystal compound has a large negative dielectric anisotropy, the threshold voltage of the liquid crystal composition containing this compound can be lowered, so that an appropriate negative voltage can be obtained as in (6). In the case of a display element using a composition containing a compound having a dielectric anisotropy, the driving voltage of the display element can be lowered and the power consumption can be reduced. And (7) in it it is possible to reduce the driving voltage of the display device by using as a display device a composition comprising a compound having a small elastic constant K _33, power consumption can be reduced.

  The liquid crystal compound is generally used as a composition prepared by mixing with many other liquid crystal compounds in order to develop characteristics that are difficult to be exhibited by a single compound. Therefore, it is preferable that the liquid crystalline compound used for the display element has good compatibility with other liquid crystalline compounds as shown in (8). In addition, since the display element may be used in a wide temperature range including below freezing point, it may be preferable that the display element is a compound showing good compatibility from a low temperature range.

A first object of the present invention has heat, light stability to such becomes a nematic phase in a wide temperature range, a small viscosity, a large optical anisotropy, and a suitable elastic constant K _33, further It is to provide a liquid crystal compound having an appropriate negative dielectric anisotropy and excellent compatibility with other liquid crystal compounds.

The second object of the present invention is to have stability against heat, light, etc., low viscosity, large optical anisotropy, and appropriate negative dielectric anisotropy, and an appropriate elastic constant K _33. A liquid crystal composition containing the above compound, having a low threshold voltage, a high upper limit temperature of the nematic phase (nematic phase-isotropic phase transition temperature), and a low lower limit temperature of the nematic phase. Is to provide.

  The third object of the present invention is to provide a liquid crystal display device containing the above composition, which has a short response time, low power consumption and low driving voltage, high contrast, and can be used in a wide temperature range. It is.

As a result of intensive studies in view of the above problems, the present inventors have found that a liquid crystalline compound having a specific structure having alkenyl and cyclohexenylene, and further having phenylene in which hydrogen on the benzene ring is replaced by fluorine, has stability to such light becomes a nematic phase in a wide temperature range, a small viscosity, a large optical anisotropy, and a suitable elastic constant K _33, further suitable negative dielectric anisotropy, In addition, the liquid crystal composition containing the above compound has stability against heat, light, etc., has a low viscosity, and a large optical anisotropy. sex, a suitable elastic constant K _33, and has suitable negative dielectric anisotropy, low threshold voltage, high maximum temperature of a nematic phase, the lower limit temperature of a nematic phase is low, further , The above group It has been found that the liquid crystal display element containing the composition has a short response time, low power consumption and driving voltage, a large contrast ratio, and can be used in a wide temperature range, and has completed the present invention.

That is, this invention has the matter described in [1]-[16] below.
[1]: A liquid crystal compound selected from the group of compounds represented by the following formula (a).

(Wherein, Ra, and Rb are independently hydrogen, alkyl having 1 to 10 carbons, or alkenyl having 2 to 10 carbon atoms, in the in the above alkyl, -CH ₂ - in -O- May be substituted, but -O- is not consecutive and hydrogen may be replaced with fluorine; ring A ¹ and ring A ² are independently trans-1,4-cyclo Hexylene, or 1,4-phenylene in which one or two hydrogens on the ring may be replaced by halogen, but one —CH ₂ — in these six-membered rings, or two not adjacent to each other —CH ₂ — may be replaced with —O—, and one or two —CH═ may be replaced with —N═, respectively;
Z ¹ and Z ² are each independently a single bond, — (CH ₂ ) ₂ —, — (CH ₂ ) ₄ —, —CH═CH—, —C≡C—, —CH ₂ O—, — OCH ₂ —, —COO—, —OCO—, or —OCF ₂ —;
l and m are independently 0, 1, or 2, but l + m is 0, 1, 2, or 3;
n is an integer of 0 to 6, and —CH ₂ — in — (CH ₂ ) n — may be replaced with —O—, but —O— is not continuous, and hydrogen is replaced with fluorine. It may be done. )
[2]: In the above formula (a), ring A ¹ and ring A ² are independently trans-1,4-cyclohexylene or 1,4-phenylene;
Z ¹ and Z ² are a single bond;
l + m is 0 or 1;
The compound according to item [1], wherein n is an integer of 0 to 6.

[3]: In the formula (a), Ra is hydrogen or alkyl having 1 to 10 carbons;
The compound according to item [2], wherein Rb is alkoxy having 1 to 9 carbons.
[4]: The compound according to item [3], wherein in formula (a), l + m is 1.

[5]: A liquid crystal composition containing at least one compound according to any one of items [1] to [4].
[6]: A first component comprising at least one compound selected from the compound group described in any one of items [1] to [4], the following formula (e-1), and formula (e- 2) and a liquid crystal composition having a negative dielectric anisotropy, comprising a second component comprising at least one compound selected from the compound group consisting of formula (e-3).

(In the formula, Ra ₁₁ and Rb ₁₁ are each independently an alkyl having 1 to 10 carbon atoms. In the alkyl, —CH ₂ — that is not adjacent to each other may be replaced by —O—. The non-adjacent — (CH ₂ ) ₂ — may be replaced with —CH═CH— and the hydrogen may be replaced with fluorine;
Ring A ¹¹ , Ring A ¹² , Ring A ¹³ and Ring A ¹⁴ are independently trans-1,4-cyclohexylene, 1,4-phenylene, 2-fluoro-1,4-phenylene, 3- Fluoro-1,4-phenylene, pyrimidine-2,5-diyl, 1,3-dioxane-2,5-diyl, or tetrahydropyran-2,5-diyl;
Z ¹¹ , Z ¹² , and Z ¹³ are each independently a single bond, —CH ₂ —CH ₂ —, —CH═CH—, —C≡C—, —COO—, or —CH ₂ O—. . )
[7]: The first component comprising at least one compound selected from the compound group described in item [3], and the formula (e-1), formula (e-2), and item [6] A liquid crystal composition having a negative dielectric anisotropy, comprising a second component comprising at least one compound selected from the group of compounds represented by formula (e-3).

  [8]: Based on the total weight of the liquid crystal composition, the content of the first component is in the range of 30 to 85% by weight, and the content of the second component is in the range of 15 to 70% by weight. The liquid crystal composition according to item [7].

  [9]: In addition to the first component and the second component, compounds represented by the following formula (g-1), formula (g-2), formula (g-3), and formula (g-4) Item 6. The liquid crystal composition according to item [6] or [7], comprising a third component comprising at least one compound selected from the group.

(In the formula, Ra ₂₁ and Rb ₂₁ are independently hydrogen or alkyl having 1 to 10 carbons, but in the alkyl, —CH ₂ — that is not adjacent to each other is replaced by —O—. Or — (CH ₂ ) ₂ — that are not adjacent to each other may be replaced by —CH═CH—, and hydrogen may be replaced by fluorine;
Ring A ²¹ , Ring A ²² , and Ring A ²³ are independently trans-1,4-cyclohexylene, 1,4-phenylene, 2-fluoro-1,4-phenylene, 3-fluoro-1, 4-phenylene, 2,3-difluoro-1,4-phenylene, pyrimidine-2,5-diyl, 1,3-dioxane-2,5-diyl, or tetrahydropyran-2,5-diyl;
Z ²¹ , Z ²² and Z ²³ are each independently a single bond, —CH ₂ —CH ₂ —, —CH═CH—, —C≡C—, —OCF ₂ —, —CF ₂ O—, — _{OCF 2 CH 2 CH 2 -,} - CH 2 CH 2 CF 2 O -, - COO -, - OCO -, - OCH 2 -, or -CH ₂ O-;
Y ¹ , Y ² , Y ³ , and Y ⁴ are independently fluorine or chlorine;
q, r, and s are independently 0, 1, or 2, but q + r + s is 1, 2, or 3;
t is 0, 1, or 2. )
[10]: The third component is represented by the following formula (h-1), formula (h-2), formula (h-3), formula (h-4), and formula (h-5). Item [9] is a liquid crystal composition comprising at least one compound selected from the group of compounds.

(In the formula, Ra ₂₂ is linear alkyl having 1 to 8 carbons or linear alkenyl having 2 to 8 carbons;
Rb ₂₂ is a straight-chain alkyl having 1 to 8 carbon atoms, a straight chain alkenyl, or alkoxy having 1 to 7 carbon atoms of 2 to 8 carbon atoms;
Z ²⁴ is a single bond or —CH ₂ CH ₂ —;
Y ¹ and Y ² are both fluorine, or one is fluorine and the other is chlorine. )
[11]: a first component comprising at least one compound selected from the compound group described in item [3], and formula (e-1) and formula (e-2) described in item [6] And a second component comprising at least one compound selected from the group of compounds represented by formula (e-3), formula (h-1) and formula (h-2) described in item [10] A dielectric anisotropy containing a third component consisting of at least one compound selected from the group of compounds represented by formulas (h-3), (h-4), and (h-5): A liquid crystal composition that is negative.

  [12]: Based on the total weight of the liquid crystal composition, the content ratio of the first component is in the range of 10 to 80% by weight, the content ratio of the second component is 10 to 80% by weight, The liquid crystal composition according to any one of items [9] to [11], wherein the content ratio of the third component is in the range of 10 to 80% by weight.

[13]: The liquid crystal composition according to any one of items [5] to [12], further comprising an antioxidant and / or an ultraviolet absorber.
[14] The liquid crystal composition according to item [13], comprising an antioxidant represented by the following formula (I).

(In the above formula (I), w represents an integer of 1 to 15)
[15]: A liquid crystal display device comprising the liquid crystal composition according to any one of items [5] to [14].

  [16] The liquid crystal display element according to item [15], wherein an operation mode of the liquid crystal display element is a VA mode or an IPS mode, and a driving method of the liquid crystal display element is an active matrix method.

The liquid crystalline compound of the present invention has stability against heat, light, etc., becomes a nematic phase over a wide temperature range, has a small viscosity, a large optical anisotropy, and an appropriate elastic constant K ₃₃ (K ₃₃ : bend elasticity). And a suitable negative dielectric anisotropy and excellent compatibility with other liquid crystal compounds. Further, the liquid crystalline compound of the present invention is particularly excellent in that the upper limit temperature of the nematic phase does not decrease and the viscosity tends to increase without increasing the optical anisotropy.

In addition, the liquid crystal composition of the present invention has a low viscosity, a large optical anisotropy, an appropriate elastic constant K ₃₃ , and an appropriate negative dielectric anisotropy, a low threshold voltage, The upper limit temperature of the nematic phase is high and the lower limit temperature of the nematic phase is low. In particular, since the liquid crystal composition of the present invention has a large optical anisotropy, it is effective for an element that requires a large optical anisotropy.

  Furthermore, the liquid crystal display device of the present invention is characterized by containing the above-mentioned composition, has a short response time, low power consumption and driving voltage, a large contrast ratio, and can be used in a wide temperature range. It can be suitably used for liquid crystal display elements in display modes such as TN mode, STN mode, ECB mode, OCB mode, IPS mode, and VA mode, and particularly suitable for liquid crystal display elements in IPS mode and VA mode. be able to.

Hereinafter, the present invention will be described more specifically.
In the following description, unless otherwise specified, the amount of the compound expressed as a percentage means a weight percentage (% by weight) based on the total weight of the composition.
[Liquid crystal compound (a)]
The liquid crystalline compound of the present invention has a structure represented by the following formula (a) (hereinafter, these compounds are also referred to as “compound (a)”).

In the formula (a), Ra and Rb are each independently hydrogen, alkyl having 1 to 10 carbons, or alkenyl having 2 to 10 carbons. In the alkyl, —CH ₂ — is —
Although it may be replaced with O-, -O- is not continuous, and hydrogen may be replaced with fluorine.

Ring A ¹ and Ring A ² are independently trans-1,4-cyclohexylene, or 1,4-phenylene in which one or two hydrogens on the ring may be replaced by halogen. In the 6-membered ring, one —CH ₂ — or two non-adjacent —CH ₂ — may be replaced by —O—, and one or two —CH═ is —N═. Each may be replaced.

Z ¹ and Z ² are each independently a single bond, — (CH ₂ ) ₂ —, — (CH ₂ ) ₄ —, —CH═CH—, —C≡C—, —CH ₂ O—, — OCH ₂ —, —COO—, —OCO— or —OCF ₂ —.

l and m are independently 0, 1, or 2, while l + m is 0, 1, 2, or 3.
n is an integer of 0 to 6, and —CH ₂ — in — (CH ₂ ) n — may be replaced with —O—, but —O— is not continuous, and hydrogen is replaced with fluorine. It may be done.

As described above, the compound (a) has alkenyl, cyclohexenylene, and 1,4-phenylene in which hydrogens at the 2-position and 3-position are replaced by fluorine. By having such a structure, it becomes a nematic phase in a wide temperature range, and has a small viscosity, a large optical anisotropy, an appropriate elastic constant K ₃₃ , an appropriate negative dielectric anisotropy, and other liquid crystal compounds. Excellent compatibility. In particular, the upper limit temperature of the nematic phase does not decrease, and the viscosity is not increased, and the optical anisotropy is particularly large.

In the above formula, Ra and Rb are the above-mentioned groups. For example, alkyl is CH ₃ (CH ₂ ) _3.
- in if it was in, -CH ₂ - in the -O-, or - (CH _{2) 2} - and -CH = CH-
CH ₃ (CH ₂ ) ₂ O—, CH ₃ —O— (CH ₂ ) ₂ —, CH ₃ —O—CH ₂ —O—; H ₂ C═CH— (CH ₂ ) ₂ —, _{CH 3 -CH = CH-CH 2} -, or CH ₃ -CH = may be CH-O-a.

However, considering the stability of the compound, oxygen and oxygen adjacent groups such as CH ₃ —O—O—CH ₂ — and double bond sites such as CH ₃ —CH═CH—CH═CH— are adjacent. Such groups are not preferred.

  More specific examples of Ra and Rb include hydrogen, alkyl, alkoxy, alkoxyalkyl, alkoxyalkoxy, alkenyl, alkenyloxy, alkenyloxyalkyl, and alkoxyalkenyl.

One or more hydrogens in these groups may be replaced with fluorine.
The chain of carbon-carbon bonds in these groups is preferably a straight chain. When the carbon-carbon bond chain is a straight chain, the temperature range of the liquid crystal phase can be widened, and the viscosity can be reduced. In addition, when either Ra or Rb is an optically active group, it is useful as a chiral dopant. By adding the compound to a liquid crystal composition, a reverse twist domain ( Reverse twisted domain) can be prevented.

The alkenyl has a preferred configuration of —CH═CH— depending on the position of the double bond in the alkenyl.
_{-CH = CHCH 3, -CH = CHC} 2 H 5, -CH = CHC 3 H 7, -CH = CHC 4 H 9
_{, -C 2 H 4 CH = CHCH} 3, the alkenyl having a double bond at an odd position, such as _{-C 2 H 4 CH = CHC 2} H 5, stereochemistry trans configuration is preferred.

On the other _{hand, -CH 2 CH = CHCH 3,} -CH 2 CH = CHC 2 H 5, in the alkenyl having a double bond at an even position, such as _{-CH 2 CH = CHC 3 H 7} , stereochemistry is cis configuration preferable. The alkenyl compound having the preferred configuration as described above has a wide temperature range of the liquid crystal phase, a large elastic constant ratio K ₃₃ / K ₁₁ (K ₃₃ : bend elastic constant, K ₁₁ : spray elastic constant), and compound Further, when this liquid crystal compound is added to the liquid crystal composition, the upper limit temperature (T _NI ) of the nematic phase can be increased.

Specific examples of the alkyl include —CH ₃ , —C ₂ H ₅ , —C ₃ H ₇ , —C ₄ H ₉ , —C ₅ H ₁₁ , —C ₆ H ₁₃ , —C ₇ H ₁₅ , —C Mention may be made of ₈ H ₁₇ , —C ₉ H ₁₉ , and —C ₁₀ H ₂₁ ;
Specific examples of the _{alkoxy, -OCH 3, -OC 2 H 5} , -OC 3 H 7, -OC 4 H 9,
_{-OC 5 H 11, -OC 6 H} 13, -OC 7 H 15, -OC 8 H 17, and can be exemplified -OC ₉ H _19;
Specific examples of the _{alkoxyalkyl, -CH 2 OCH 3, -CH 2} OC 2 H 5, -CH 2 OC 3 H 7, - (CH 2) 2 OCH 3, - (CH 2) 2 OC 2 H 5 _{, - (CH 2) 2 OC} 3 H 7, - (
_{CH 2) 3 OCH 3, -} (CH 2) 4 OCH 3, and - (CH _{2) 5} OCH ₃ can be cited;
Specific examples of the alkenyl include —CH═CH ₂ , —CH═CHCH ₃ , —CH ₂ CH═.
_{CH 2, -CH = CHC 2 H} 5, -CH 2 CH = CHCH 3, - (CH 2) 2 CH = CH 2, -CH = CHC 3 H 7, -CH 2 CH = CHC 2 H 5, - ( _{CH 2) 2 CH = CHCH 3} , and - (CH ₂₎ can be cited ₃ CH = CH _2;
Specific examples of the _{alkenyloxy, -OCH 2 CH = CH 2,} -OCH 2 CH = CH
Mention may be made of CH ₃ , —OCH ₂ CH═CHC ₂ H ₅ , and —O (CH ₂ ) ₂ CH═CH ₂ .

Specific examples of alkyl in which hydrogen is replaced with halogen include —CH ₂ F, —CHF ₂ , —CF ₃ , — (CH ₂ ) ₂ F, —CF ₂ CH ₂ F, —CF ₂ CHF ₂ , — _{CH 2 CF 3, -CF 2 CF} 3, - (CH 2) 3 F, - (CF 2) 2 CF 3, -CF 2 CHFCF 3, and -CHFCF ₂ CF ₃ can be cited;
Specific examples of alkoxy in which hydrogen is replaced with halogen include —OCF ₃ , —OCHF ₂ , —OCH ₂ F, —OCF ₂ CF ₃ , —OCF ₂ CHF ₂ , —OCF ₂ CH ₂ F, —OCF ₂ CF ₂ C
F _3, -OCF ₂ CHFCF _3, and -OCHFCF ₂ CF ₃ can be cited;
Specific examples of the alkenyl replacing the hydrogen with a halogen, -CH = CHF, -CH = CF 2, -CF = CHF, -CH = CHCH 2 F, -CH = CHCF 3, and - (CH _{2) 2}
CH = CF ₂ may be mentioned.

Since Ra is a group bonded to —CH═CH—, when Ra is a group such as CH ₃ —CH═CH—, the structure is CH ₃ —CH═CH—CH═CH—. Such a structure in which double bonds are continuous is not preferable because it is unstable to light.

Therefore, among the specific examples of Ra, hydrogen, —CH ₃ , —C ₂ H ₅ , —C ₃ H ₇ , —C ₄ H ₉ , —
_{C 5 H 11, -OCH 3,} -OC 2 H 5, -OC 3 H 7, -OC 4 H 9, -OC 5 H 11, -CH 2 OCH 3, - (CH 2) 2 OCH 3, - ( _{CH 2) 3 OCH 3, -CH} 2 CH = CH 2, -CH 2 CH = CHCH 3, - (CH 2) 2 CH = CH 2, -CH 2 CH = CHC 2 H 5, - (CH 2) 2 CH =
CHCH ₃ , — (CH ₂ ) ₃ CH═CH ₂ , — (CH ₂ ) ₃ CH═CHCH ₃ , — (CH ₂ ) ₃ C
_{H = CHC 2 H 5, -} (CH 2) 3 CH = CHC 3 H 7, -OCH 2 CH = CH 2, -OCH 2 C
H = CHCH ₃ , —OCH ₂ CH═CHC ₂ H ₅ , —CF ₃ , —CHF ₂ , —CH ₂ F, —OC
F ₃ , —OCHF ₂ , —OCH ₂ F, —OCF ₂ CF ₃ , —OCF ₂ CHF ₂ , —OCF ₂ CH ₂
F, —OCF ₂ CF ₂ CF ₃ , —OCF ₂ CHFCF ₃ , and —OCHFCF ₂ CF ₃ are preferable, and hydrogen, —CH ₃ , —C ₂ H ₅ , —C ₃ are preferable because they are excellent in light resistance and heat resistance. H ₇
Is more preferable.

Among specific examples of Rb, hydrogen, —CH ₃ , —C ₂ H ₅ , —C ₃ H ₇ , —C ₄ H ₉ , —C ₅ H ₁₁ , —OCH ₃ , —OC ₂ H ₅ , — OC ₃ H ₇ , —OC ₄ H ₉ , —OC ₅ H ₁₁ , —CH ₂ OCH ₃ , — (CH ₂ ) ₂ OCH ₃ , — (CH ₂ ) ₃ OCH ₃ , —CH═CH ₂ , —CH═ CHCH ₃ , —CH ₂ CH═CH ₂ , —CH═CHC ₂ H ₅ , —CH ₂ CH═CHCH ₃ , — (CH ₂ ) ₂ CH═CH ₂ , —CH═CHC ₃ H ₇ , —CH ₂ CH _{= CHC 2 H 5, - (} CH 2) 2 CH = CHCH 3
_{, - (CH 2) 3 CH} = CH 2, -OCH 2 CH = CH 2, -OCH 2 CH = CHCH 3, -O
_{CH 2 CH = CHC 2 H 5} , -CF 3, -CHF 2, -CH 2 F, -OCF 3, -OCHF 2, -OCH 2 F, -OCF 2 CF 3, -OCF 2 CHF 2, -OCF 2 _{CH 2 F, -OCF 2 CF 2} C
F ₃ , —OCF ₂ CHFCF ₃ , and —OCHFCF ₂ CF ₃ are preferred, are chemically stable, and have a large negative dielectric anisotropy, —OCH ₃ , —OC ₂ H ₅ , —OC ₃ H ₇
, —OC ₄ H ₉ , and —OC ₅ H ₁₁ are more preferable, and hydrogen, —CH ₃ , —C ₂ H ₅ , —C ₃ H ₇ from the viewpoint of excellent compatibility with other liquid crystal compounds at low temperatures. _{, -C 4 H 9, -C 5} H 11, -CH 2 CH = CHCH 3, - (CH 2) 2 CH = CH 2, -CH 2 CH = CHC 2 H 5, - (CH 2) 2 CH = CHCH ₃ and — (CH ₂ ) ₃ CH═CH ₂ are more preferred.

Ring A ¹ and Ring A ² are independently 1,4-cyclohexylene, 1,4-phenylene in which one or two hydrogens on the ring may be replaced by halogen, and in these rings One —CH ₂ — or two non-adjacent —CH ₂ — may be replaced with —O—, and one or two —CH═ may be replaced with —N═.

Examples of the ring A ¹ and the ring A ² include trans-1,4-cyclohexylene, trans-1,3-dioxane-2,5-diyl, trans-tetrahydropyran-2,5-diyl, 1,4- Phenylene, 2-fluoro-1,4-phenylene, 3-fluoro-1,4-phenylene, 2,3-difluoro-1,4-phenylene, 2,5-difluoro-1,4-phenylene, 2,6- Difluoro-1,4-phenylene, pyridine-2,5-diyl, 6-fluoropyridine-2,5-diyl, and pyridazine-2,5-diyl are preferred.

  Among these rings, trans-1,4-cyclohexylene and 1,4-phenylene are more preferable in terms of being chemically stable, exhibiting a high clearing point, and having a low viscosity, and negative dielectric anisotropy. 2-Fluoro-1,4-phenylene, 3-fluoro-1,4-phenylene, and 2,3-difluoro-1,4-phenylene are more preferable from the viewpoint of being large, and 1 from the viewpoint of high optical anisotropy. , 4-phenylene, 2-fluoro-1,4-phenylene, 3-fluoro-1,4-phenylene, 2,3-difluoro-1,4-phenylene, 2,5-difluoro-1,4-phenylene, 2, , 6-difluoro-1,4-phenylene, pyridine-2,5-diyl, 6-fluoropyridine-2,5-diyl, and pyridazine-2,5-diyl are preferred. Further, trans-tetrahydropyran-2,5-diyl is more preferable from the viewpoint of excellent compatibility with other liquid crystal compounds.

In particular, when at least two of these rings are trans-1,4-cyclohexylene, the viscosity can be reduced, and when this liquid crystalline compound is added to the liquid crystal composition, the upper limit of the nematic phase is increased. The temperature (T _NI ) can be increased.

Further, when at least one of these rings is 1,4-phenylene, the optical anisotropy (Δn) tends to be increased, and the orientational order parameter can be increased. .

Further, when at least two rings are 1,4-phenylene, the optical anisotropy can be further increased.
Z ¹ and Z ² are a single bond, — (CH ₂ ) ₂ —, — (CH ₂ ) ₄ —, —CH═CH—, —C≡C—, —CH ₂ O—, —OCH ₂ —. , —COO—, —OCO—, or —OCF ₂ —
It is.

Z ^1, and Z ^2, considered a single bond the stability of the compound, and - (CH _{2) 2} - are preferred from the viewpoint such as excellent compatibility with other liquid crystal compounds - (CH _{2) 2} - ,-(CH _2
4 −, —CH═CH—, —CH ₂ O—, —OCH ₂ —, —COO—, —OCO—, or —OCF ₂ — are preferred, and —CH═CH from the viewpoint of high optical anisotropy. -Or-
C≡C— is preferred.

When Z ¹ and Z ² are —CH═CH—, the steric configuration of the other group with respect to the double bond is preferably a trans configuration. By such a configuration, the temperature range of the liquid crystal phase of the liquid crystal compound can be expanded, and further, when this liquid crystal compound is added to the liquid crystal composition, the upper limit temperature (T _NI ) of the nematic phase is increased. Can be high.

In addition, when —CH═CH— is contained in Z ¹ and Z ² , the temperature range of the liquid crystal phase is widened, and the elastic constant ratio K ₃₃ / K ₁₁ (K ₃₃ : bend elastic constant, (K ₁₁ : spray elastic constant) can be increased, and the viscosity of the compound can be decreased. Further, when this liquid crystal compound is added to the liquid crystal composition, the upper limit temperature (T _NI ) of the nematic phase is increased. Can do.

Since there is no significant difference in the physical properties of the compound, the liquid crystal compound (a) is ² H (deuterium), an isotope such as ¹³ C may contain more than the amount of natural abundance.
In these liquid crystalline compounds (a), Ra, Rb, ring A ¹ , ring A ² , Z ¹ , and Z ² are appropriately selected within the above range, thereby making physical properties such as dielectric anisotropy desired properties. It is possible to adjust.

Among the compounds represented by the above formula (a), ring A ¹ and ring A ² are independently trans-1,4-cyclohexylene or 1,4-phenylene, Z ¹ , and When Z ² is a single bond, l + m is 0 or 1, and n is an integer of 0 to 6, it is excellent in heat resistance and light resistance. Among these, the compound whose n is 0, 2, 4, or 6 is more preferable from the viewpoint that the maximum temperature of the nematic phase is high and the viscosity is small. Moreover, the compound whose n is 1, 3, or 5 is more preferable at the point that it is excellent in compatibility with another liquid crystalline compound.

  In particular, among the above compounds, Ra is hydrogen, alkyl having 1 to 10 carbons, or alkenyl having 2 to 10 carbons, and Rb is alkyl having 1 to 10 carbons or alkoxy having 1 to 9 carbons Is more preferable from the viewpoints of being excellent in heat resistance and light resistance, having a smaller viscosity, lowering the lower limit temperature of the nematic phase, and increasing the upper limit temperature. In particular, when l + m = 1, the upper limit temperature of the nematic phase can be further increased.

When the liquid crystalline compound has a structure represented by these liquid crystalline compounds (a), it has an appropriate negative dielectric anisotropy and is extremely compatible with other liquid crystalline compounds. Furthermore, the heat has stability to such light becomes a nematic phase in a wide temperature range, a small viscosity, and has a large optical anisotropy, and a suitable elastic constant K _33. In addition, the liquid crystal composition containing the liquid crystal compound (a) is stable under the conditions in which the liquid crystal display device is normally used, and the compound precipitates as crystals (or smectic phases) even when stored at a low temperature. There is nothing to do.

  Therefore, the liquid crystalline compound (a) can be suitably applied to a liquid crystal composition used in a liquid crystal display element of a display mode such as PC, TN, STN, ECB, OCB, IPS, VA, and the like, such as IPS, VA, etc. The present invention can be particularly preferably applied to a liquid crystal composition used in a display mode liquid crystal display element.

[Synthesis of Liquid Crystalline Compound (a)]
The liquid crystalline compound (a) can be synthesized by appropriately combining synthetic methods of organic synthetic chemistry. Methods for introducing the desired end groups, rings, and linking groups into the starting materials include, for example, Organic Syntheses (John Wiley & Sons, Inc), Organic Reactions (Organic Reactions, John Wiley & Sons, Inc), It is described in books such as Comprehensive Organic Synthesis (Pergamon Press) and New Experimental Chemistry Course (Maruzen).
<Formation of cyclohexenylene>
An example of a method for forming cyclohexenylene is shown in the following scheme. In this scheme, MSG ¹ or MSG ² is a monovalent organic group. A plurality of MSG ¹ (or MSG ² ) used in the scheme may be the same or different. Compound (1A) corresponds to liquid crystal compound (a).

<Formation of cyclohexenylene>
An organic halogen compound (a1) having a monovalent organic group MSG ² is reacted with magnesium to prepare a Grignard reagent. Or a compound (a3) having a monovalent organic group MSG ²
And n-butyllithium or sec-butyllithium are reacted to prepare a lithium salt. The corresponding alcohol derivative is synthesized by reacting the prepared Grignard reagent or lithium salt with the cyclohexanone derivative (a2). Next, a compound (1A) having cyclohexenylene corresponding to the liquid crystalline compound (a) is synthesized by dehydrating the obtained alcohol derivative using an acid catalyst such as p-toluenesulfonic acid. Can do. The cyclohexanone derivative (a2) can be synthesized, for example, according to the method described in JP-A-59-7122.

<Formation of linking group Z ¹ or Z ² >
An example of a method for forming the linking group Z ¹ or Z ² is shown. A scheme for forming a linking group is shown below. In this scheme, MSG ¹ or MSG ² is a monovalent organic group. A plurality of MSG ¹ (or MSG ² ) used in the scheme may be the same or different. From compound (1B) to compound (1I) corresponds to liquid crystal compound (a).

<Generation of double bond>
An organic halogen compound (a1) having a monovalent organic group MSG ² is reacted with magnesium to prepare a Grignard reagent. By reacting these prepared Grignard reagents with the aldehyde derivative (a4) or (a5), the corresponding alcohol derivative is synthesized. Then, by performing a dehydration reaction of the obtained alcohol derivative using an acid catalyst such as p-toluenesulfonic acid, the corresponding compound (1B) or (a6) having a double bond can be synthesized.

  A compound obtained by treating the organic halogen compound (a1) with butyllithium or magnesium is reacted with formamide such as N, N-dimethylformamide (DMF) to obtain an aldehyde derivative (a7). Subsequently, the obtained aldehyde (a7) is reacted with phosphorus ylide obtained by treating the phosphonium salt (a8) with a base such as potassium t-butoxide (t-BuOK), and the compound having a corresponding double bond ( 1B) can be synthesized. In the above reaction, a cis isomer may be generated depending on the reaction conditions. Therefore, when it is necessary to obtain a trans isomer, the cis isomer is isomerized into a trans isomer by a known method as necessary.

<- (CH _{2) 2} - generation of>
The compound (1C) can be synthesized by hydrogenating the compound (1B) in the presence of a catalyst such as palladium on carbon (Pd / C).

<Formation of — (CH ₂ ) ₄ —>
An aldehyde derivative (a7), a phosphonium salt (a9) and a phosphorus ylide obtained by treatment with a base such as potassium t-butoxide are reacted to synthesize a compound (a6) having a corresponding double bond. Next, compound (1D) can be synthesized by hydrogenating compound (a6) in the presence of a catalyst such as Pd / C.

<Generation of single bond>
An organic halogen compound (a10) having a monovalent organic group MSG ¹ is reacted with magnesium or butyl lithium to prepare a Grignard reagent or a lithium salt. The dihydroxyborane derivative (a11) is synthesized by reacting the prepared Grignard reagent or lithium salt with a borate ester such as trimethyl borate and hydrolyzing the acid with an acid such as hydrochloric acid. By reacting the dihydroxyborane derivative (a11) and the organic halogen compound (a1) in the presence of a catalyst comprising, for example, an aqueous carbonate solution and tetrakis (triphenylphosphine) palladium (Pd (PPh ₃ ) ₄ ). Compound (1E) can be synthesized.

Further, after reacting the organic halogen compound (a10) with butyllithium and further with zinc chloride, the resulting compound is converted into, for example, the presence of a bistriphenylphosphine dichloropalladium (Pd (PPh ₃ ) ₂ Cl ₂ ) catalyst. Compound (1E) can also be synthesized by reacting with compound (a1) below.

<Formation of —CH ₂ O— or —OCH ₂ —>
The dihydroxyborane derivative (a11) is oxidized with an oxidizing agent such as hydrogen peroxide to obtain the alcohol derivative (a12). Separately, the alcohol derivative (a13) is obtained by reducing the aldehyde derivative (a7) with a reducing agent such as sodium borohydride. The obtained alcohol derivative (a13) is halogenated with hydrobromic acid or the like to obtain an organic halogen compound (a14). The compound (1F) can be synthesized by reacting the alcohol derivative (a12) thus obtained with the organic halogen compound (a14) in the presence of potassium carbonate or the like.

<Generation of -COO- and -OCO->
The compound (a10) is reacted with n-butyllithium and subsequently with carbon dioxide to obtain a carboxylic acid derivative (a15). Carboxylic acid derivative (a15) and phenol derivative (a16) are dehydrated in the presence of 1,3-dicyclohexylcarbodiimide (DCC) and 4-dimethylaminopyridine (DMAP) to obtain compound (1G) having —COO—. Can be synthesized.

<Formation of -CF ₂ O- and -OCF _2- >
Compound (a17) is obtained by treating compound (1G) with a sulfurizing agent such as Lawesson's reagent. The compound (a17) is fluorinated with a hydrogen fluoride pyridine complex and NBS (N-bromosuccinimide) to synthesize a compound (1H) having —CF ₂ O—. See M. Kuroboshi et al., Chem. Lett., 1992, 827. Compound (1H) can also be synthesized by fluorinating compound (a17) with (diethylamino) sulfur trifluoride (DAST). See WH Bunnelle et al., J. Org. Chem. 1990, 55, 768. A compound having —OCF ₂ — is also synthesized by this method. These linking groups can also be generated by the method described in Peer. Kirsch et al., Anbew. Chem. Int. Ed. 2001, 40, 1480.

<Generation of -C≡C->
Compound (a18) is obtained by reacting compound (a10) with 2-methyl-3-butyn-2-ol in the presence of a catalyst of dichloropalladium and copper halide, followed by deprotection under basic conditions. . Compound (a18) is reacted with compound (a1) in the presence of a catalyst of dichloropalladium and copper halide to synthesize compound (1I).

[Method for Producing Liquid Crystalline Compound (a)]
Hereinafter, production examples of the liquid crystalline compound (a), that is, the liquid crystalline compound represented by the general formula (a) are shown.

  A lithium salt is prepared by reacting compound (b1) with sec-BuLi. This lithium salt and carbonyl derivative (b2) are reacted to obtain an alcohol derivative (b3). The resulting alcohol derivative (b3) is dehydrated in the presence of an acid catalyst such as p-toluenesulfonic acid to obtain a cyclohexene derivative (b4). The compound (b4) is hydrolyzed in an acid atmosphere such as formic acid to obtain a carbonyl derivative (b5). The resulting carbonyl derivative (b5) is subjected to Wittig reaction with phosphoylide prepared from a base such as methoxymethyltriphenylphosphonium chloride and potassium t-butoxide (t-BuOK) to obtain an enol ether derivative (b6). . The obtained enol ether derivative (b6) is hydrolyzed under an acid atmosphere and, if necessary, further isomerized under basic conditions to obtain an aldehyde derivative (b7). This aldehyde derivative (b7) is reacted with phosphorylide prepared from butyltriphonylphosphonium bromide and a base such as t-BuOK to obtain a mixture (b8) of E-form and Z-form. By isomerizing it in the presence of sodium benzenesulfinate and hydrochloric acid, (b9) which is an example of the liquid crystal compound (a) of the present invention can be produced.

[Liquid crystal composition]
Hereinafter, the liquid crystal composition of the present invention will be described. The component of the liquid crystal composition is characterized by containing at least one liquid crystal compound (a), but may contain two or more liquid crystal compounds (a), and only from the liquid crystal compound (a). It may be configured. Moreover, when preparing the liquid crystal composition of this invention, a component can also be selected in consideration of the dielectric anisotropy of a liquid crystalline compound (a), for example. The liquid crystal composition, a low viscosity, has suitable negative dielectric anisotropy, has a suitable elastic constant K _33, low threshold voltage, maximum temperature of a nematic phase (nematic phase -Phase transition temperature of isotropic phase) is high, and minimum temperature of nematic phase is low.

[Liquid crystal composition (1)]
In addition to the liquid crystal compound (a) as a first component, the liquid crystal composition of the present invention has a liquid crystal compound represented by the following formula (e-1) to formula (e-3) as a second component (hereinafter referred to as compound ( A composition further containing at least one compound selected from the group of e-1) to compound (e-3)) is preferred (hereinafter also referred to as liquid crystal composition (1)).

In the above formulas (e-1) to (e-3), Ra ₁₁ and Rb ₁₁ are independently alkyl having 1 to 10 carbons, but —CH ₂ that is not adjacent to each other in the alkyl. - may be replaced by -O-, not adjacent to each - (CH _{2) 2} - may be replaced by -CH = CH-, hydrogen may be replaced by fluorine.

In the above formulas (e-1) to (e-3), ring A ¹¹ , ring A ¹² , ring A ¹³ , and ring A ¹⁴ are independently trans-1,4-cyclohexylene, 1, 4-phenylene, 2-fluoro-1,4-phenylene, 3-fluoro-1,4-phenylene, pyrimidine-2,5-diyl, 1,3-dioxane-2,5-diyl, and tetrahydropyran-2, 5-Diyl.

In the above formulas (e-1) to (e-3), Z ¹¹ , Z ¹² , and Z ¹³ are each independently a single bond, —CH ₂ —CH ₂ —, —CH═CH—, —C ≡C—, —COO—, or CH ₂ O—.

By containing the second component in the liquid crystal compound (a), the viscosity of the liquid crystal composition can be reduced, and the nematic phase region can be expanded.
For example, the compound (e-1) is an effective compound for reducing the viscosity of the liquid crystal composition containing the compound (e-1) and increasing the specific resistance value.

The compound (e-2) is an effective compound for increasing the maximum temperature of the nematic phase of the liquid crystal composition containing it and increasing the specific resistance value.
Further, the compound (e-3) is an effective compound for increasing the upper limit temperature of the nematic phase of the liquid crystal composition containing the compound and increasing the specific resistance value.

In ring A ¹¹ , ring A ¹² , ring A ¹³ , and ring A ¹⁴ , when two or more rings are trans-1,4-cyclohexylene, the upper limit temperature of the nematic phase of the liquid crystal composition containing the ring is set to In the case where two or more rings are 1,4-phenylene, the optical anisotropy of the composition containing the ring can be increased.

Among the second components, more preferable compounds are compounds represented by the following formulas (2-1) to (2-74) (hereinafter also referred to as compounds (2-1) to (2-74)). ). In these compounds, Ra ₁₁ and Rb ₁₁ have the same meaning as in the case of the compounds (e-1) to (e-3).

  When the second component is the compound (2-1) to the compound (2-74), a liquid crystal composition having excellent heat resistance and light resistance, a higher specific resistance value, and a wide nematic phase is obtained. Can be prepared.

The content of the second component in the liquid crystal composition (1) of the present invention is not particularly limited, but the content is preferably increased from the viewpoint of lowering the viscosity. However, since the threshold voltage of the liquid crystal composition tends to increase when the content of the second component is increased, for example, when the liquid crystal composition of the present invention is used in a VA mode liquid crystal element, The content of the second component is in the range of 15 to 70% by weight with respect to the total weight of the liquid crystal composition, and the content of the first component is 30 to 85 with respect to the total weight of the liquid crystal composition. A range of% by weight is more preferred.

In particular, the first component is at least one compound selected from the group of compounds represented by formula (a) wherein Ra is hydrogen, alkyl having 1 to 10 carbons, and Rb is alkoxy having 1 to 9 carbons. The liquid crystal composition (1), in which the second component is at least one compound selected from the compound group represented by the compounds (e-1) to (e-3), has excellent heat resistance and light resistance. excellent, has broad nematic phase, the specific resistance value is large, a small viscosity, and shows a suitable elastic constant K _33.

[Liquid crystal composition (2)]
As the liquid crystal composition of the present invention, in addition to the first component and the second component, a liquid crystal compound represented by the following formula (g-1) to formula (g-4) (hereinafter referred to as the third component) A liquid crystal composition containing at least one compound selected from the group consisting of compound (g-1) to compound (g-4) is also preferable (hereinafter also referred to as liquid crystal composition (2)).

In the formulas (g-1) to (g-4), Ra ₂₁ and Rb ₂₁ are independently hydrogen or alkyl having 1 to 10 carbons, but are not adjacent to each other in the alkyl. -CH ₂
- may be replaced by -O-, not adjacent to each - (CH _{2) 2} - may be replaced by -CH = CH-, hydrogen may be replaced by fluorine.

In the above formulas (g-1) to (g-4), the rings A ²¹ , A ²² , and A ²³ are independently trans-1,4-cyclohexylene, 1,4-phenylene, 2- Fluoro-1,4-phenylene, 3-fluoro-1,4-phenylene, 2,3-difluoro-1,4-phenylene, pyrimidine-2,5-diyl, 1,3-dioxane-2,5-diyl, Or tetrahydropyran-2,5-diyl.

In the above formulas (g-1) to (g-4), Z ²¹ , Z ²² , and Z ²³ are each independently a single bond, —CH ₂ —CH ₂ —, —CH═CH—, —C ≡C—, —OCF ₂ —, —CF ₂ O—, —OCF ₂ CH ₂ CH ₂ —, —CH ₂ CH ₂ CF ₂ O—, —COO—, —OCO—, —OCH ₂ —, or —CH ₂ O—, Y ¹ , Y ² , Y ³ , and Y ⁴ are independently fluorine or chlorine.

In the above formulas (g-1) to (g-4), q, r, and s are independently 0, 1, or 2, but q + r + s is 1, 2, or 3, and t is 0, 1, or 2.
The liquid crystal composition (2) further containing the third component has a large negative dielectric anisotropy. In addition, a liquid crystal composition having a wide nematic phase temperature range, a low viscosity, a large negative dielectric anisotropy and a large specific resistance value can be obtained, and a liquid crystal composition in which these physical properties are appropriately balanced Things are obtained.

  In addition, among the third components, from the viewpoint of low viscosity and excellent heat resistance and light resistance, compounds represented by the following formulas (h-1) to (h-5) (hereinafter, compounds) (H-1) to at least one compound selected from the group of compounds (h-5)) is preferred.

In the above formulas (h-1) to (h-5), Ra ₂₂ is linear alkyl having 1 to 8 carbons or linear alkenyl having 2 to 8 carbons, and Rb ₂₂ is carbon 1 8 linear alkyl, linear alkenyl or alkoxy having 1 to 7 carbon atoms, 2 to 8 carbon atoms, Z ²⁴ is a single bond or -CH ₂ CH ₂ -.

In the above formulas (h-1) to (h-5), Y ¹ and Y ² are all fluorine, or one is fluorine and the other is chlorine.
For example, a compound having a condensed ring such as compound (g-2) to compound (g-4) can reduce the threshold voltage value. For example, the compound (h-1) and the compound (h-2) can reduce the viscosity of the liquid crystal composition containing the compound (h-1) and lower the threshold voltage value. Compound (h-2) and Compound (h-3) increase the maximum temperature of the nematic phase of the liquid crystal composition containing the compound, decrease the threshold voltage value, and increase the optical anisotropy. Can do. Compound (h-4) and Compound (h-5) increase the maximum temperature of the nematic phase of the liquid crystal composition containing the compound, increase the optical anisotropy, and decrease the threshold voltage value. be able to.

In particular, in the liquid crystal composition (2), at least one selected from the group of compounds represented by the formula (a) wherein Ra is hydrogen, alkyl having 1 to 10 carbons, and Rb is alkoxy having 1 to 9 carbons. A first component comprising a compound, a second component comprising at least one compound selected from the group of compounds comprising the above formula (e-1), formula (e-2) and formula (e-3), and the above From at least one compound selected from the group of compounds represented by formula (h-1), formula (h-2), formula (h-3), formula (h-4), and formula (h-5) The liquid crystal composition containing the third component is excellent in heat resistance and light resistance, has a wide nematic phase temperature range, a low viscosity, a large negative dielectric anisotropy, a large specific resistance value, and an appropriate value. The elastic constant K ₃₃ is shown. Furthermore, it is preferable in terms of a liquid crystal composition in which these physical properties are appropriately balanced.

Among the third components, more preferable compounds are the compound (3-1) to the compound (3-68). In these compounds, Ra ₂₂ and Rb ₂₂ have the same meanings as in the case of the above compound (h-1) to compound (h-5).

Although there is no restriction | limiting in particular in content of the said 3rd component in the liquid-crystal composition of this invention, It is preferable to increase content from a viewpoint that the absolute value of negative dielectric constant anisotropy is not made small.
The content ratios of the first component, the second component, and the third component of the liquid crystal composition (2) according to the present invention are not particularly limited, but based on the total weight of the liquid crystal composition (2), Preferably, the content ratio of the compound (a) is in the range of 10 to 80% by weight, the content ratio of the second component is in the range of 10 to 80% by weight, and the content ratio of the third component is in the range of 10 to 80% by weight. Furthermore, the content ratio of the first component is in the range of 10 to 70% by weight, the content ratio of the second component is in the range of 10 to 50% by weight, and the content ratio of the third component is in the range of 20 to 60% by weight. Is more preferable.

When the content ratio of the first component, the second component, and the third component of the liquid crystal composition (2) is in the above range, the heat resistance and light resistance are excellent, the temperature range of the nematic phase is wide, and the viscosity is high. The dielectric constant anisotropy is small, the dielectric anisotropy is negatively large, the specific resistance is large, and an appropriate elastic constant K ₃₃ is exhibited. Furthermore, a liquid crystal composition in which these physical properties are more appropriately balanced can be obtained.

[Mode of liquid crystal composition, etc.]
In the liquid crystal composition according to the present invention, in addition to the first component, the liquid crystal compound constituting the second component and the third component, which are added as necessary, for example, for the purpose of further adjusting the characteristics of the liquid crystal composition. In some cases, other liquid crystal compounds are added and used. Further, for example, from the viewpoint of cost, in the liquid crystal composition of the present invention, no liquid crystal compound other than the liquid crystal compounds constituting the first component, the second component and the third component is added as necessary. It may be used for

Moreover, you may add additives, such as an optically active compound, a pigment | dye, an antifoamer, a ultraviolet absorber, antioxidant, to the liquid-crystal composition concerning this invention.
When an optically active compound is added to the liquid crystal composition according to the present invention, a helical structure can be induced in the liquid crystal to give a twist angle. When the dye is added to the liquid crystal composition according to the present invention, the liquid crystal composition can be applied to a liquid crystal display element having a GH (Guest host) mode. When the antifoaming agent is added to the liquid crystal composition according to the present invention, it becomes possible to suppress foaming during the transportation of the liquid crystal composition or during the production process of the liquid crystal display element from the liquid crystal composition. . When an ultraviolet absorber or an antioxidant is added to the liquid crystal composition according to the present invention, it becomes possible to prevent deterioration of the liquid crystal composition and the liquid crystal display device containing the liquid crystal composition. For example, the antioxidant can suppress a decrease in specific resistance value when the liquid crystal composition is heated.

  Examples of the ultraviolet absorber include benzophenone ultraviolet absorbers, benzoate ultraviolet absorbers, and triazole ultraviolet absorbers. A specific example of the benzophenone ultraviolet absorber is 2-hydroxy-4-n-octoxybenzophenone. A specific example of the benzoate ultraviolet absorber is 2,4-di-t-butylphenyl-3,5-di-t-butyl-4-hydroxybenzoate. Specific examples of the triazole ultraviolet absorber include 2- (2-hydroxy-5-methylphenyl) benzotriazole, 2- [2-hydroxy-3- (3,4,5,6-tetrahydroxyphthalimide-methyl)- 5-methylphenyl] benzotriazole, and 2- (3-tert-butyl-2-hydroxy-5-methylphenyl) -5-chlorobenzotriazole.

  As said antioxidant, a phenolic antioxidant, an organic sulfur type antioxidant, etc. can be mentioned. In particular, from the viewpoint that the antioxidant effect is high without changing the physical properties of the liquid crystal composition, an antioxidant represented by the following formula is preferable.

In the above formula (I), w represents an integer of 1 to 15.
Specific examples of the phenolic antioxidant include 2,6-di-t-butyl-4-methylphenol, 2,6-di-t-butyl-4-ethylphenol, 2,6-di-t-butyl- 4-propylphenol, 2,6-di-t-butyl-4-butylphenol, 2,6-di-t-butyl-4-pentylphenol, 2,6-di-t-butyl-4-hexylphenol, 2 , 6-di-t-butyl-4-heptylphenol, 2,6-di-t-butyl-4-octylphenol, 2,6-di-t-butyl-4-nonylphenol, 2,6-di-t- Butyl-4-decylphenol, 2,6-di-tert-butyl-4-undecylphenol, 2,6-di-tert-butyl-4-dodecylphenol, 2,6-di-tert-butyl-4- Tridecylphenol, 2,6-di-t Butyl-4-tetradecylphenol, 2,6-di-t-butyl-4-pentadecylphenol, 2,2′-methylenebis (6-t-butyl-4-methylphenol), 4,4′-butylidenebis (6 -T-butyl-3-methylphenol), 2,6-di-t-butyl-4- (2-octadecyloxycarbonyl) ethylphenol, and pentaerythritol tetrakis [3- (3,5-di-t-butyl) -4-hydroxyphenyl) propionate].

  Specific examples of the organic sulfur antioxidant include dilauryl-3,3′-thiopropionate, dimyristyl-3,3′-thiopropionate, distearyl-3,3′-thiopropionate, pentaerythritol. Tetrakis (3-lauryl thiopropionate) and 2-mercaptobenzimidazole.

  The amount of the additive typified by an ultraviolet absorber, an antioxidant and the like can be added and used within a range that does not impair the purpose of the present invention and can achieve the purpose of adding the additive.

  For example, when the ultraviolet absorber or the antioxidant is added, the addition ratio is usually in the range of 10 ppm to 500 ppm, preferably 30 to 300 ppm, based on the total weight of the liquid crystal composition according to the present invention. The range is more preferably 40 to 200 ppm.

  The liquid crystal composition according to the present invention includes impurities such as synthesis raw materials, by-products, reaction solvents, and synthesis catalysts mixed in the synthesis process of each compound constituting the liquid crystal composition, the liquid crystal composition preparation process, and the like. In some cases.

[Method for producing liquid crystal composition]
In the liquid crystal composition according to the present invention, for example, when the compound constituting each component is a liquid, the respective compounds are mixed and shaken, and when the compound includes a solid, the respective compounds are mixed. It can be prepared by making each liquid by heating and then shaking. The liquid crystal composition according to the present invention can also be prepared by other known methods.

[Characteristics of liquid crystal composition]
In the liquid crystal composition according to the present invention, the upper limit temperature of the nematic phase can be set to 70 ° C. or more, the lower limit temperature of the nematic phase can be set to −20 ° C. or less, and the temperature range of the nematic phase is wide. Therefore, a liquid crystal display element including this liquid crystal composition can be used in a wide temperature range.

  In the liquid crystal composition according to the present invention, the optical anisotropy can be set in the range of 0.10 to 0.13 and in the range of 0.05 to 0.18 by appropriately adjusting the composition and the like. In the liquid crystal composition according to the present invention, the dielectric anisotropy is usually in the range of -5.0 to -2.0, preferably the dielectric anisotropy in the range of -4.5 to -2.5. A liquid crystal composition having properties can be obtained. The liquid crystal composition in the above numerical range can be suitably used as a liquid crystal display element that operates in the IPS mode and the VA mode.

[Liquid crystal display element]
The liquid crystal composition according to the present invention has operation modes such as a PC mode, a TN mode, an STN mode, and an OCB mode, and is not only a liquid crystal display element driven by an AM mode, but also a PC mode, a TN mode, an STN mode, an OCB. It can also be used for a liquid crystal display element having an operation mode such as a mode, a VA mode, and an IPS mode and driven by a passive matrix (PM) method. These AM-type and PM-type liquid crystal display elements can be applied to any liquid crystal display such as a reflective type, a transmissive type, and a transflective type.

  The liquid crystal composition according to the present invention includes a DS (dynamic scattering) mode element using a liquid crystal composition to which a conductive agent is added, and an NCAP (nematic curvilinear aligned phase) element prepared by microencapsulating the liquid crystal composition. It can also be used for PD (polymer dispersed) elements in which a three-dimensional network polymer is formed in a liquid crystal composition, for example, PN (polymer network) elements.

  In particular, since the liquid crystal composition according to the present invention has the above-described characteristics, an AM mode liquid crystal driven in an operation mode using a liquid crystal composition having a negative dielectric anisotropy such as a VA mode or an IPS mode. The present invention can be suitably used for a display element, and in particular, can be suitably used for an AM liquid crystal display element driven in a VA mode.

  Note that in a liquid crystal display element driven in a TN mode, a VA mode, or the like, the direction of the electric field is perpendicular to the liquid crystal layer. On the other hand, in the liquid crystal display element driven in the IPS mode or the like, the direction of the electric field is parallel to the liquid crystal layer. The structure of the liquid crystal display element driven in the VA mode is reported in K. Ohmuro, S. Kataoka, T. Sasaki and Y. Koike, SID '97 Digest of Technical Papers, 28, 845 (1997). The structure of the liquid crystal display element driven in the IPS mode is reported in International Publication No. 91/10936 pamphlet (family: US5576867).

[Example]
[Examples of liquid crystal compound (a)]
EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not restrict | limited by these Examples. Unless otherwise specified, “%” means “% by weight”.

Since the obtained compound was identified by a nuclear magnetic resonance spectrum obtained by ¹ H-NMR analysis, a gas chromatogram obtained by gas chromatography (GC) analysis, etc., the analysis method will be described first.

¹ H-NMR analysis DRX-500 (Bruker Biospin Co., Ltd.) was used as the measurement apparatus. The measurement was carried out by dissolving the sample produced in Examples and the like in a deuterated solvent in which a sample such as CDCl ₃ is soluble, and at room temperature under conditions of 500 MHz and 24 times of integration. In the description of the obtained nuclear magnetic resonance spectrum, s is a singlet, d is a doublet, t is a triplet, q is a quartet, and m is a multiplet. Tetramethylsilane (TMS) was used as a reference material for the zero point of the chemical shift δ value.

GC analysis As a measuring apparatus, a GC-14B gas chromatograph manufactured by Shimadzu Corporation was used. As the column, a capillary column CBP1-M25-025 (length 25 m, inner diameter 0.32 mm, film thickness 0.25 μm) manufactured by Shimadzu Corporation; dimethylpolysiloxane; nonpolar) was used as the stationary liquid phase. Helium was used as the carrier gas, and the flow rate was adjusted to 1 ml / min. The temperature of the sample vaporizing chamber was set to 280 ° C., and the temperature of the detector (FID) portion was set to 300 ° C.

The sample was dissolved in toluene to prepare a 1% by weight solution, and 1 μl of the resulting solution was injected into the sample vaporization chamber.
As a recorder, a C-R6A type Chromatopac manufactured by Shimadzu Corporation or an equivalent thereof was used. The obtained gas chromatogram shows the peak retention time and peak area value corresponding to the component compounds.

As a sample dilution solvent, for example, chloroform or hexane may be used. In addition, as a column, capillary column DB-1 (length 30 m, inner diameter 0.32 mm, film thickness 0.25 μm) manufactured by Agilent Technologies Inc., HP manufactured by Agilent Technologies Inc.
-1 (length 30 m, inner diameter 0.32 mm, film thickness 0.25 μm), Rtx-1 (length 30 m, inner diameter 0.32 mm, film thickness 0.25 μm) manufactured by Restek Corporation, manufactured by SGE International Pty. Ltd. BP-1 (length 30 m, inner diameter 0.32 mm, film thickness 0.25 μm) or the like may be used.

  The area ratio of peaks in the gas chromatogram corresponds to the ratio of component compounds. In general, the weight% of the component compound of the analysis sample is not completely the same as the area% of each peak of the analysis sample. However, when the above-described column is used in the present invention, the correction factor is substantially 1. Therefore, the weight% of the component compound in the analysis sample substantially corresponds to the area% of each peak in the analysis sample. This is because there is no significant difference in the correction coefficients of the component liquid crystal compounds. In order to more accurately determine the composition ratio of the liquid crystal compound in the liquid crystal composition by gas chromatogram, an internal standard method using gas chromatogram is used. The liquid crystal compound component (test component) weighed in a certain amount accurately and the reference liquid crystal compound (reference material) are simultaneously measured by gas chromatography, and the area ratio between the peak of the obtained test component and the peak of the reference material Is calculated in advance. When correction is performed using the relative intensity of the peak area of each component with respect to the reference substance, the composition ratio of the liquid crystal compound in the liquid crystal composition can be determined more accurately from gas chromatography analysis.

[Samples for measuring physical properties of liquid crystal compounds, etc.]
There are two types of samples for measuring the physical property values of the liquid crystal compound: when the compound itself is used as a sample, and when the compound is mixed with a mother liquid crystal as a sample.

  In the latter case using a sample in which a compound is mixed with mother liquid crystals, the measurement is performed by the following method. First, 15% by weight of the obtained liquid crystal compound and 85% by weight of the mother liquid crystal are mixed to prepare a sample. Then, an extrapolated value is calculated from the measured value of the obtained sample according to the extrapolation method shown in the following equation. This extrapolated value is taken as the physical property value of this compound.

<Extrapolated value> = (100 × <Measured value of sample> − <Weight% of mother liquid crystal> × <Measured value of mother liquid crystal>) / <Weight% of liquid crystalline compound>
Even when the ratio between the liquid crystal compound and the mother liquid crystal is this ratio, when the smectic phase or crystal is precipitated at 25 ° C., the ratio of the liquid crystal compound and the mother liquid crystal is 10% by weight: 90% by weight, 5% by weight: 95% by weight, 1% by weight: 99% by weight. The physical properties of the sample were measured with a composition in which the smectic phase or crystals did not precipitate at 25 ° C. An interpolated value is obtained and used as a physical property value of the liquid crystal compound.

There are various types of mother liquid crystals used for the measurement. For example, the composition of the mother liquid crystals i is as follows.
Mother liquid crystal i:

Note that the liquid crystal composition itself was used as a sample for measuring physical properties of the liquid crystal composition.
[Method for measuring physical properties of liquid crystal compounds, etc.]
The physical property values were measured by the method described later. Many of these measurement methods are the methods described in the Standard of Electric Industries Association of Japan EIAJ / ED-2521A or a modified method thereof. Moreover, TFT was not attached to the TN element or VA element used for the measurement.

  Among the measured values, the values obtained using the liquid crystal compound itself as a sample and the values obtained using the liquid crystal composition itself as a sample are described as experimental data. When the compound was mixed with mother liquid crystals and obtained as a sample, the value obtained by extrapolation was taken as the extrapolated value.

Phase structure and transition temperature (℃)
Measurement was carried out by the method (1) or (2) below.
(1) A compound is placed on a hot plate (Mettler FP-52 type hot stage) equipped with a polarizing microscope, and the phase state and its change are observed with a polarizing microscope while heating at a rate of 3 ° C./min. , Identified the type of phase.
(2) Perkin Elmer scanning calorimeter DSC-7 system or Diamond D
Using the SC system, the temperature was raised and lowered at a rate of 3 ° C./min, the endothermic peak accompanying the phase change of the sample, or the starting point of the exothermic peak was determined by extrapolation (on set), and the transition temperature was determined.

Hereinafter, the crystal was expressed as C. When the crystal could be distinguished, it was expressed as C ₁ or C ₂ , respectively. Further, the smectic phase is represented as S and the nematic phase is represented as N. The liquid (isotropic) was designated as I. In the smectic phase, when the smectic B phase or the smectic A phase can be distinguished, they are represented as S _B or S _A , respectively. As a notation of the transition temperature, for example, “C 50.0 N 100.0 I” means that the transition temperature (CN) from the crystal to the nematic phase is 50.0 ° C., and the transition temperature from the nematic phase to the liquid ( NI) is 100.0 ° C. The same applies to other notations.

Maximum temperature of nematic phase (T _NI ; ° C)
A sample (a liquid crystalline composition or a mixture of a liquid crystal compound and a mother liquid crystal) is placed on a hot plate (Mettler FP-52 type hot stage) of a melting point measurement apparatus equipped with a polarizing microscope, and 1 ° C.
The polarizing microscope was observed while heating at a rate of / min. The temperature at which a part of the sample changed from a nematic phase to an isotropic liquid was defined as the upper limit temperature of the nematic phase. Hereinafter, the upper limit temperature of the nematic phase may be simply abbreviated as “upper limit temperature”.

Low-temperature compatibility Sample in which mother liquid crystal and liquid crystal compound are mixed so that the liquid crystal compound is 20% by weight, 15% by weight, 10% by weight, 5% by weight, 3% by weight, and 1% by weight. And put the sample in a glass bottle. The glass bottle was stored in a freezer at −10 ° C. or −20 ° C. for a certain period, and then it was observed whether a crystal or smectic phase was precipitated.

Viscosity (η; measured at 20 ° C .; mPa · s)
It measured using the E-type rotational viscometer.
Rotational viscosity (γ1; measured at 25 ° C .; mPa · s)
The measurement followed the method described in M. Imai et al., Molecular Crystals and Liquid Crystals, Vol. 259, 37 (1995). A sample (a liquid crystal composition or a mixture of a liquid crystal compound and a mother liquid crystal) was put in a VA device having a distance (cell gap) between two glass substrates of 20 μm. This element was applied stepwise in increments of 1 volt in the range of 30 to 50 volts. After no application for 0.2 seconds, the application was repeated under the condition of only one rectangular wave (rectangular pulse; 0.2 seconds) and no application (2 seconds). The peak current and peak time of the transient current generated by this application were measured. The value of rotational viscosity was obtained from these measured values and the paper by M. Imai et al., Formula (8) on page 40. The dielectric anisotropy necessary for this calculation was a value measured by the following dielectric anisotropy.

Optical anisotropy (refractive index anisotropy; measured at 25 ° C .; Δn)
The measurement was performed at 25 ° C. using an Abbe refractometer using light with a wavelength of 589 nm and a polarizing plate attached to the eyepiece. After rubbing the surface of the main prism in one direction, a sample (a liquid crystalline composition or a mixture of a liquid crystal compound and a mother liquid crystal) was dropped onto the main prism. The refractive index (n‖) was measured when the direction of polarized light was parallel to the direction of rubbing. The refractive index (n⊥) was measured when the direction of polarized light was perpendicular to the direction of rubbing. The value of optical anisotropy (Δn) was calculated from the equation: Δn = n∥−n⊥.

Dielectric anisotropy (Δε; measured at 25 ° C)
The dielectric anisotropy was measured by the following method.
An ethanol (20 mL) solution of octadecyltriethoxysilane (0.16 mL) was applied to a well-cleaned glass substrate. The glass substrate was rotated with a spinner and then heated at 150 ° C. for 1 hour. A VA device having an interval (cell gap) of 20 μm was assembled from two glass substrates. In the same manner, a polyimide alignment film was prepared on a glass substrate. After the alignment film of the obtained glass substrate was rubbed, a TN device in which the distance between the two glass substrates was 9 μm and the twist angle was 80 degrees was assembled. A sample (a liquid crystal composition or a mixture of a liquid crystal compound and a mother liquid crystal) is placed in the obtained VA element, 0.5 V (1 kHz, sine wave) is applied, and the dielectric constant (in the major axis direction of the liquid crystal molecules ( ε‖) was measured. In addition, a sample (a liquid crystal composition or a mixture of a liquid crystal compound and a mother liquid crystal) is put into the obtained TN device, 0.5 V (1 kHz, sine wave) is applied, and the dielectric in the minor axis direction of the liquid crystal molecules The rate (ε⊥) was measured. The value of dielectric anisotropy was calculated from the equation: Δε = ε∥−ε⊥.

Voltage holding ratio (VHR; measured at 25 ° C .;%)
The TN device used for the measurement has a polyimide alignment film, and the distance (cell gap) between the two glass substrates is 6 μm. This element was sealed with an adhesive that was polymerized by ultraviolet rays after a sample (a liquid crystal composition or a mixture of a liquid crystal compound and a mother liquid crystal) was added. The TN device was charged by applying a pulse voltage (60 microseconds at 5 V). The decaying voltage was measured with a high-speed voltmeter for 16.7 milliseconds, and the area A between the voltage curve and the horizontal axis in a unit cycle was obtained. The area B is an area when it is not attenuated. The voltage holding ratio is expressed as a percentage (%) of the area A with respect to the area B.

Elastic constant (K ₁₁ , K ₃₃ ; measured at 25 ° C)
An EC-1 type elastic constant measuring instrument manufactured by Toyo Corporation was used for the measurement. A sample was put in a vertical alignment cell in which the distance between two glass substrates (cell gap) was 20 μm. A 20 to 0 volt charge was applied to the cell, and the capacitance and applied voltage were measured. Fitting the measured values of capacitance (C) and applied voltage (V) using “Liquid Crystal Device Handbook” (Nikkan Kogyo Shimbun), formulas (2.98) and (2.101) on page 75 The value of the elastic constant was obtained from the formula (2.100).

  Synthesis of 4- (4-ethoxy-2,3-difluorophenyl) -trans-4'-vinylbicyclohexyl-3-ene (No. 132)

First Step 6.1 g of well-dried magnesium and 20 ml of THF were added to a reactor under a nitrogen atmosphere and heated to 40 ° C. There, 1-bromo-4 dissolved in 300 ml of THF
-Ethoxy-2,3-difluorobenzene (1) 59.7g was dripped slowly in the temperature range of 40 to 60 degreeC, and also it stirred for 60 minutes. Thereafter, 50.0 g of 4- (1,4-dioxaspiro [4.5] dec-8-yl) -cyclohexanone (2) dissolved in 150 ml of THF was slowly dropped in a temperature range of 50 ° C. to 60 ° C., and Stir for 60 minutes. The obtained reaction mixture was cooled to 30 ° C., poured into a container containing 900 ml of 3% aqueous ammonium chloride cooled to 0 ° C. and 500 ml of toluene, mixed, allowed to stand, and the organic and aqueous layers. And the extraction operation was performed. The obtained organic layer was separated, washed with water, saturated aqueous sodium hydrogen carbonate, and water, and dried over anhydrous magnesium sulfate. Thereafter, the solvent was distilled off under reduced pressure, and 4- (1,4-dioxaspiro [4.5] dec-8-yl) -1- (4-ethoxy-2,3-difluorophenyl) -cyclohexanol (3 ) 100.1 g was obtained.
The obtained compound (3) was a yellow solid.

Second Step 100.1 g of Compound (3), 1.0 g of p-toluenesulfonic acid, 1.0 g of ethylene glycol, and 300 ml of toluene were mixed, and this mixture was heated to reflux for 2 hours while removing distilled water. . After cooling the reaction mixture to 30 ° C., the resulting liquid was poured into water 500
ml and 900 ml of toluene were added and mixed, and then allowed to stand to separate into two layers, an organic layer and an aqueous layer, and an extraction operation into the organic layer was performed. The obtained organic layer was separated, washed with saturated aqueous sodium hydrogen carbonate and water, and dried over anhydrous magnesium sulfate. The resulting solution was purified by preparative operation by column chromatography using toluene as a developing solvent and silica gel as a filler, and recrystallized from a mixed solvent of toluene and heptane (volume ratio: toluene: heptane = 1: 1). And dried, 8- [4- (4-ethoxy-2,3-difluorophenyl) -cyclohex-3-enyl] -1,4-dioxaspiro [4.5] decane (4) 58.1
g was obtained. The yield based on the compound (2) was 73.2%.

Third Step 58.1 g of compound (4), 35.4 g of 87% formic acid, and 200 ml of toluene were mixed, and the mixture was heated to reflux for 2 hours. After cooling the reaction mixture to 30 ° C., 500 ml of water and 1000 ml of toluene were added to the obtained liquid and mixed, and then allowed to stand to separate into two layers, an organic layer and an aqueous layer, and an extraction operation into the organic layer Went. The obtained organic layer was separated, washed with water, saturated aqueous sodium hydrogen carbonate, and water, and dried over anhydrous magnesium sulfate. Thereafter, the solvent was distilled off under reduced pressure to obtain 54 g of a pale yellow solid. 54 g of this solid, 35.4 g of 87% formic acid, and 200 ml of toluene were mixed, and this mixture was heated to reflux for 1 hour. After cooling the reaction mixture to 30 ° C., 500 ml of water and 1000 ml of toluene were added to the obtained liquid and mixed, and then allowed to stand to separate into two layers, an organic layer and an aqueous layer, and an extraction operation into the organic layer Went. The obtained organic layer was separated, washed with water, saturated aqueous sodium hydrogen carbonate, and water, and dried over anhydrous magnesium sulfate. Thereafter, the solvent was distilled off under reduced pressure, and the residue was purified by recrystallization from a mixed solvent of toluene and heptane (volume ratio of toluene: heptane = 1: 2), dried, and 4 ′-(4-ethoxy-2 , 3-Difluorophenyl) -bicyclohexyl-3′-en-4-one (5) 49.7 g was obtained. The yield based on the compound (4) was 96.7%.

Step 4 Methoxymethyltriphenylphosphonium chloride well dried under nitrogen atmosphere 5
7.7 g and 200 ml of THF were mixed and cooled to -30 ° C. Then potassium t-
Butoxide (t-BuOK) 18.1 g was added in four portions in the temperature range of -30 ° C to -20 ° C. After stirring at −20 ° C. for 30 minutes, the compound dissolved in 135 ml of THF (
5) 45.0g was dripped in the temperature range of -30 degreeC to -20 degreeC. After stirring at −10 ° C. for 30 minutes, the reaction mixture was poured into a mixture of 400 ml of water and 400 ml of toluene, mixed, and allowed to stand to separate into two layers, an organic layer and an aqueous layer, and extracted into the organic layer. The operation was performed. The obtained organic layer was separated, washed with water, and dried over anhydrous magnesium sulfate. The resulting solution was concentrated under reduced pressure, and the residue was mixed with heptane and toluene (volume ratio heptane: toluene = 7:
3) was purified by a preparative operation by column chromatography using a developing solvent and silica gel as a filler. The obtained eluent was concentrated under reduced pressure to obtain 51.6 g of slightly yellow 4- (4-ethoxy-2,3-difluorophenyl) -4′-methoxymethylene-bicyclohexyl-3-ene (6). It was.

Step 5 Compound (6) 51.6 g, 87% formic acid 37.7 g, and toluene 200 ml were mixed, and the mixture was heated to reflux for 2 hours. After cooling the reaction mixture to 30 ° C., 500 ml of water and 1000 ml of toluene were added to the obtained liquid and mixed, and then allowed to stand to separate into two layers, an organic layer and an aqueous layer, and an extraction operation into the organic layer Went. The obtained organic layer was separated, washed with water, saturated aqueous sodium hydrogen carbonate, and water, and dried over anhydrous magnesium sulfate. Thereafter, the solvent was distilled off under reduced pressure to obtain 51.2 g of a pale yellow solid. This residue was dissolved in 50 ml of toluene, added to a mixed solution of 0.5 g of 95% sodium hydroxide cooled to 7 ° C. and 400 ml of methanol, and stirred at 10 ° C. for 2 hours. Then, 20 ml of 2N sodium hydroxide aqueous solution was added, and it stirred at 5 degreeC for 2 hours. The obtained reaction mixture was poured into a mixed solution of 2000 ml of water and 2000 ml of toluene, mixed, and allowed to stand to separate into two layers, an organic layer and an aqueous layer, and an extraction operation into the organic layer was performed. The obtained organic layer was separated, washed with water, and dried over anhydrous magnesium sulfate. Thereafter, the solvent was distilled off under reduced pressure, and the resulting residue was purified by recrystallization from a mixed solvent of heptane and THF (volume ratio heptane: THF = 4: 1), dried and dried as a white solid 4′- 43.5 g of (4-ethoxy-2,3-difluorophenyl) -bicyclohexyl-3′-ene-trans-4-carbaldehyde (7) was obtained. The yield based on the compound (5) was 92.7%.

Step 6 Under a nitrogen atmosphere, 8.6 g of well-dried methyltriphenylphosphonium bromide and 40 ml of THF were mixed and cooled to −10 ° C. Then potassium t-butoxide (
(t-BuOK) 2.7 g was charged in 3 times in the temperature range of -10 ° C to -5 ° C.
After stirring at −10 ° C. for 60 minutes, 7.0 g of Compound (7) dissolved in 14 ml of THF was added dropwise in the temperature range of −10 ° C. to −5 ° C. After stirring at 0 ° C. for 30 minutes, the reaction mixture was poured into a mixture of 100 ml of water and 50 ml of toluene, mixed, and allowed to stand to separate into two layers, an organic layer and an aqueous layer, and extraction into the organic layer. Went. The obtained organic layer was separated, washed with water, and dried over anhydrous magnesium sulfate. The obtained solution was concentrated under reduced pressure, and the resulting residue was fractionated by column chromatography using a mixed solvent of heptane and toluene (volume ratio heptane: toluene = 3: 1) as a developing solvent and silica gel as a filler. The eluent was concentrated under reduced pressure. The obtained residue was purified by recrystallization from a mixed solvent (volume ratio heptane: Solmix A-11 = 2: 1) of heptane and Solmix A-11 (manufactured by Nippon Alcohol Sales Co., Ltd.). 5.6 g of (4-ethoxy-2,3-difluorophenyl) -trans-4′-vinylbicyclohexyl-3-ene (No. 132) was obtained. The yield based on the compound (7) was 80.3%.

The transition temperature of the obtained compound (No. 132) is as follows.
Transition temperature: C 77.8 S _A 96.9 N 160.8 I
The chemical shift δ (ppm) of ¹ H-NMR analysis is as follows, and the obtained compound is
It could be identified as 4- (4-ethoxy-2,3-difluorophenyl) -trans-4′-vinylbicyclohexyl-3-ene. The measurement solvent is CDCl ₃ .

  Chemical shift δ (ppm); 6.87 (td, 1H), 6.65 (td, 1H), 5.91 (t, 1H), 5.81-5.75 (m, 1H), 4.96 (Dt, 1H), 4.88 (dt, 1H), 4.10 (q, 2H), 2.38-2.32 (m, 2H), 2.25-2.22 (m, 1H), 1.98-1.80 (m, 7H), 1.47-1.31 (m, 5H), 1.14-1.03 (m, 5H).

  Synthesis of 4- (4-ethoxy-2,3-difluorophenyl) -trans-4'-propenylbicyclohexyl-3-ene (No. 152)

10.2 g of ethyltriphenylphosphonium bromide well dried under nitrogen atmosphere
And 40 ml of THF were mixed and cooled to -10 ° C. Thereafter, 3.0 g of potassium t-butoxide (t-BuOK) was added in three portions at a temperature range of −10 ° C. to −5 ° C. After stirring at −10 ° C. for 60 minutes, 8.0 g of Compound (7) dissolved in 16 ml of THF was added dropwise in the temperature range of −10 ° C. to −5 ° C. After stirring at 0 ° C. for 30 minutes, the reaction mixture is washed with water 1
The mixture was poured into a mixed solution of 00 ml and 50 ml of toluene, mixed, and allowed to stand to separate into two layers, an organic layer and an aqueous layer, and an extraction operation into the organic layer was performed. The obtained organic layer was separated, washed with water, and dried over anhydrous magnesium sulfate. The obtained solution was concentrated under reduced pressure, and the resulting residue was fractionated by column chromatography using a mixed solvent of heptane and toluene (volume ratio heptane: toluene = 3: 1) as a developing solvent and silica gel as a filler. The eluent was concentrated under reduced pressure to obtain 8.2 g of a white solid. To 8.2 g of the obtained white solid, 32 ml of Solmix A-11 was added, and while stirring, 6.7 g of sodium benzenesulfinate dihydrate was added, followed by 10 ml of 6N-hydrochloric acid, Heated to reflux for 5 hours. After the reaction mixture was cooled to 30 ° C., 100 ml of water and 100 ml of toluene were added to and mixed with the resulting liquid. Then, it left still and isolate | separated into two layers, an organic layer and an aqueous layer, and extraction operation to the organic layer was performed. The obtained organic layer was separated, washed with water, 0.5N aqueous sodium hydroxide solution, saturated aqueous sodium bicarbonate, and water, and dried over anhydrous magnesium sulfate. The resulting solution is concentrated under reduced pressure, and the residue is purified by preparative operation by column chromatography using a mixed solvent of heptane and toluene (volume ratio heptane: toluene = 3: 1) as a developing solvent and silica gel as a filler. The eluent was concentrated under reduced pressure. The obtained residue was purified by recrystallization from a mixed solvent of heptane and Solmix A-11 (volume ratio heptane: Solmix A-11 = 3: 1) to give 4- (4-ethoxy-2,3-difluoro 1.37 g of (phenyl) -trans-4′-propenylbicyclohexyl-3-ene (No. 152) was obtained. The yield based on the compound (7) was 16.6%.

The transition temperature of compound (No. 152) obtained is as follows.
Transition temperature: C ₁ 78.9 C ₂ 83.4 N 201.1 I
The chemical shift δ (ppm) of ¹ H-NMR analysis is as follows, and the obtained compound is
It could be identified as 4- (4-ethoxy-2,3-difluorophenyl) -trans-4′-propenylbicyclohexyl-3-ene. The measurement solvent is CDCl ₃ .

  Chemical shift δ (ppm); 6.87 (td, 1H), 6.65 (td, 1H), 5.91 (t, 1H), 5.43-5.34 (m, 2H), 4.10 (Q, 2H), 2.42-2.32 (m, 2H), 2.25-2.21 (m, 1H), 1.97-1.73 (m, 7H), 1.64 (d , 3H), 1.45-1.30 (m, 5H), 1.13-0.98 (m, 5H).

  Synthesis of trans-4'-but-3-enyl-4- (4-ethoxy-2,3-difluorophenyl) bicyclohexyl-3-ene (No. 172)

First Step Methoxymethyltriphenylphosphonium chloride well dried under nitrogen atmosphere 2
9.5 g and 120 ml of THF were mixed and cooled to -30 ° C. Then potassium t-
9.7 g of butoxide (t-BuOK) was added in four portions in the temperature range of -30 ° C to -20 ° C. After stirring at −20 ° C. for 60 minutes, 25.0 g of Compound (7) dissolved in 50 ml of THF was added dropwise in the temperature range of −20 ° C. to −10 ° C. After stirring at 0 ° C. for 30 minutes, the reaction mixture was poured into a mixed solution of 400 ml of water and 200 ml of toluene, mixed, and allowed to stand to separate into two layers, an organic layer and an aqueous layer, and an extraction operation into the organic layer Went. The obtained organic layer was separated, washed with water, and dried over anhydrous magnesium sulfate. The obtained solution was concentrated under reduced pressure, and the resulting residue was mixed with heptane and toluene (volume ratio heptane: toluene = 7: 3).
) In a preparative operation by column chromatography using a developing solvent and silica gel as a filler. The obtained eluent was concentrated under reduced pressure to obtain 27.0 g of a slightly yellow solid.
Subsequently, 27.0 g of this solid, 100 ml of toluene and 37.9 g of 87% formic acid were mixed and heated to reflux for 3 hours. After cooling the reaction mixture to 30 ° C.,
200 ml and 200 ml of toluene were added and mixed. Then, it left still and isolate | separated into two layers, an organic layer and an aqueous layer, and extraction operation to the organic layer was performed. The obtained organic layer was separated, washed with water, saturated aqueous sodium hydrogen carbonate, and water, and dried over anhydrous magnesium sulfate. Thereafter, the solvent was distilled off under reduced pressure, and the resulting residue was mixed with a mixed solvent of heptane and THF (volume ratio heptane: THF = 2:
Purified by recrystallization from 1), dried and white [4 ′-(4-ethoxy-2,3-difluorophenyl) bicyclohexyl-3′-en-trans-4-yl] acetaldehyde (8) 43 .5 g was obtained. The yield based on the compound (7) was 94.7%.

Second Step Methoxymethyltriphenylphosphonium chloride well dried under nitrogen atmosphere 1
9.3 g and 80 ml of THF were mixed and cooled to -25 ° C. Thereafter, 6.3 g of potassium t-butoxide (t-BuOK) was added in four portions at a temperature range of -25 ° C to -15 ° C. After stirring at −20 ° C. for 60 minutes, 17.0 g of Compound (8) dissolved in 40 ml of THF was added dropwise in the temperature range of −20 ° C. to −10 ° C. After stirring at 0 ° C. for 30 minutes, the reaction mixture was poured into a mixed solution of 200 ml of water and 100 ml of toluene and mixed. Then, it left still and isolate | separated into two layers, an organic layer and an aqueous layer, and extraction operation to the organic layer was performed. The obtained organic layer was separated, washed with water, and dried over anhydrous magnesium sulfate. The obtained solution was concentrated under reduced pressure, and the resulting residue was fractionated by column chromatography using a mixed solvent of heptane and toluene (volume ratio heptane: toluene = 7: 3) as a developing solvent and silica gel as a filler. Purified with. The obtained eluent was concentrated under reduced pressure to obtain 19.1 g of a slightly yellow solid. Subsequently, 19.1 g of this solid, 100 ml of toluene, and 25.9 g of 87% formic acid were mixed and heated to reflux for 3 hours. After cooling the reaction mixture to 30 ° C., 200 ml of water and 200 ml of toluene were added to the resulting liquid and mixed, and then allowed to stand to separate into two layers, an organic layer and an aqueous layer, and an extraction operation into the organic layer Went. The obtained organic layer was separated, washed with water, saturated aqueous sodium hydrogen carbonate, and water, and dried over anhydrous magnesium sulfate. Thereafter, the solvent was distilled off under reduced pressure, and the resulting residue was purified by recrystallization from a mixed solvent of heptane and THF (volume ratio heptane: THF = 2: 1), dried, and white 3- [4 16.7 g of '-(4-ethoxy-2,3-difluorophenyl) bicyclohexyl-3'-en-trans-4-yl] propionaldehyde (9) was obtained. The yield based on the compound (8) was 94.4%.

Step 3 4.55 g of methyltriphenylphosphonium bromide well dried in a nitrogen atmosphere
And 20 ml of THF were mixed and cooled to -10 ° C. Thereafter, 1.43 g of potassium t-butoxide (t-BuOK) was added in three portions in the temperature range of −10 ° C. to −5 ° C. After stirring at −5 ° C. for 60 minutes, 4.0 g of Compound (9) dissolved in 10 ml of THF was added dropwise in a temperature range of −10 ° C. to −5 ° C. After stirring at 0 ° C. for 30 minutes, the reaction mixture is washed with water 1
The mixture was poured into a mixed solution of 00 ml and 50 ml of toluene and mixed. Then, it left still and isolate | separated into two layers, an organic layer and an aqueous layer, and extraction operation to the organic layer was performed. The obtained organic layer was separated, washed with water, and dried over anhydrous magnesium sulfate. The obtained solution was concentrated under reduced pressure, and the resulting residue was fractionated by column chromatography using a mixed solvent of heptane and toluene (volume ratio heptane: toluene = 4: 1) as a developing solvent and silica gel as a filler. The eluent was concentrated under reduced pressure. The obtained residue was purified by recrystallization from a mixed solvent of heptane and Solmix A-11 (volume ratio heptane: Solmix A-11 = 2: 1) to obtain trans-4′-but-3-enyl-4. -(4-Ethoxy-2,3-difluorophenyl) bicyclohexyl-3-ene (No. 172) 3.34 g was obtained. The yield based on the compound (9) was 84.0%.

The transition temperature of compound (No. 172) obtained is as follows.
Transition temperature: C 66.2 S _A 118.6 N 174.1 I
The chemical shift δ (ppm) of ¹ H-NMR analysis is as follows, and the obtained compound is
It could be identified as trans-4′-but-3-enyl-4- (4-ethoxy-2,3-difluorophenyl) bicyclohexyl-3-ene. The measurement solvent is CDCl ₃ .

  Chemical shift δ (ppm); 6.87 (td, 1H), 6.65 (td, 1H), 5.91 (t, 1H), 5.86-5.78 (m, 1H), 5.00 (Dd, 1H), 4.92 (dd, 1H), 4.10 (q, 2H), 2.40-2.32 (m, 2H), 2.24-2.21 (m, 1H), 2.09-2.04 (m, 2H), 1.97-1.88 (m, 2H), 1.83-1.75 (m, 4H), 1.46-1.26 (m, 7H) ), 1.23-1.11 (m, 2H), 1.07-0.85 (m, 4H).

  Synthesis of 4- (4-ethoxy-2,3-difluorophenyl) -trans-4'-pent-3-enylbicyclohexyl-3-ene (No. 192)

8.28 g of ethyltriphenylphosphonium bromide well dried under nitrogen atmosphere
And 40 ml of THF were mixed and cooled to -10 ° C. Thereafter, 2.50 g of potassium t-butoxide (t-BuOK) was added in three portions in the temperature range of −10 ° C. to −5 ° C. After stirring at −5 ° C. for 60 minutes, 7.00 g of the compound (9) dissolved in 20 ml of THF was added dropwise at −5 ° C. After stirring at 0 ° C. for 30 minutes, the reaction mixture was poured into a mixed solution of 100 ml of water and 100 ml of toluene and mixed. Then, it left still and isolate | separated into two layers, an organic layer and an aqueous layer, and extraction operation to the organic layer was performed. The obtained organic layer was separated, washed with water, and dried over anhydrous magnesium sulfate. The obtained solution was concentrated under reduced pressure, and the resulting residue was fractionated by column chromatography using a mixed solvent of heptane and toluene (volume ratio heptane: toluene = 4: 1) as a developing solvent and silica gel as a filler. The eluent was concentrated under reduced pressure to obtain 7.77 g of a white solid. To 7.77 g of the obtained white solid, 31 ml of Solmix A-11 was added. While stirring, 12.0 g of sodium benzenesulfinate dihydrate was added, followed by 31 ml of 6N hydrochloric acid, Heated to reflux for 5 hours. After cooling the reaction mixture to 30 ° C., 100 ml of water and 100 ml of toluene were added to and mixed with the resulting liquid, and then allowed to stand to separate into two layers, an organic layer and an aqueous layer, and an extraction operation into the organic layer Went. The obtained organic layer was separated, washed with water, 0.5N aqueous sodium hydroxide solution, saturated aqueous sodium bicarbonate, and water, and dried over anhydrous magnesium sulfate. The obtained solution was concentrated under reduced pressure, and the resulting residue was fractionated by column chromatography using a mixed solvent of heptane and toluene (volume ratio heptane: toluene = 3: 1) as a developing solvent and silica gel as a filler. The eluent was concentrated under reduced pressure. The obtained residue was purified by recrystallization from a mixed solvent of heptane and Solmix A-11 (volume ratio heptane: Solmix A-11 = 3: 1), dried, and white 4- (4-ethoxy- 2,3-difluorophenyl) -trans-4′-pent-3-enylbicyclohexyl-3-ene (No. 192) 1.50 g was obtained. The yield based on the compound (9) was 20.8%.

The transition temperature of compound (No. 192) obtained is as follows.
Transition temperature: C 64.4 S _A 123.7 N 189.3 I
The chemical shift δ (ppm) of ¹ H-NMR analysis is as follows, and the obtained compound is
It could be identified as 4- (4-ethoxy-2,3-difluorophenyl) -trans-4′-pent-3-enylbicyclohexyl-3-ene. The measurement solvent is CDCl ₃
It is.

  Chemical shift δ (ppm); 6.87 (td, 1H), 6.65 (td, 1H), 5.91 (m, 1H), 5.46-5.37 (m, 2H), 4.10 (Q, 2H), 2.40-2.32 (m, 2H), 2.24-2.21 (m, 1H), 2.00-1.74 (m, 8H), 1.64 (d , 3H), 1.45-1.30 (m, 5H), 1.27-1.10 (m, 4H), 1.06-0.84 (m, 4H).

  Synthesis of 1-ethoxy-2,3-difluoro-4- (4-vinylcyclohex-1-enyl) benzene (No. 12)

Step 1 To a reactor under a nitrogen atmosphere, 200.0 g of 1,4-dioxaspiro [4.5] decan-8-one (10), 301.4 g of ethyl diethylphosphonoacetate and 1,000 ml of toluene were added. Stir at 5 ° C. Thereto, 457.5 g of a 20% sodium ethoxide ethanol solution was dropped in a temperature range of 5 ° C. to 11 ° C. over 2 hours, and further stirred at 10 ° C. for 3 hours. After confirming the completion of the reaction by GC analysis, the reaction mixture was poured into 2,000 ml of water at 0 ° C. and mixed. Thereafter, the mixture was allowed to stand to separate into an organic layer and an aqueous layer, and an extraction operation into the organic layer was performed. The obtained organic layer was separated, washed with water, and dried over anhydrous magnesium sulfate. Thereafter, the solvent was distilled off under reduced pressure, and the obtained residue was purified by a fractionation operation by column chromatography using heptane as a developing solvent and silica gel as a filler. Thereafter, the solvent was distilled off under reduced pressure to obtain 267.3 g of (1,4-dioxaspiro [4,5] dec-8-ylidene) acetic acid ethyl ester (11) as a slightly yellow liquid.

Second Step 267.3 g of Compound (11), 5.0 g of Pd / C, 500 ml of isopropyl alcohol (IPA) and 500 ml of toluene were added to the reactor, and the mixture was stirred under a hydrogen atmosphere for 24 hours. After confirming the completion of the reaction by GC analysis, Pd / C was filtered off and the solvent was distilled off under reduced pressure to obtain a residue. The obtained residue was purified by a preparative operation by column chromatography using heptane as a developing solvent and silica gel as a filler, and the solvent was distilled off under reduced pressure to give a colorless transparent liquid (1,4-dioxaspiro). There were obtained 255.2 g of [4,5] dec-8-yl) acetic acid ethyl ester (12).

Step 3 To the reactor under nitrogen atmosphere, 20.0 g of lithium aluminum hydride (LAH) and TH
F (800 ml) was added, and the mixture was stirred at 3 ° C. A compound (1 dissolved in 200 ml of THF)
2) 190.0 g was added dropwise in the temperature range of 0 ° C. to 7 ° C. over 2 hours, and further stirred at 0 ° C. for 3 hours. After confirming the completion of the reaction by GC analysis, a mixture of 60 ml of THF and 60 ml of acetone was added dropwise at 0 ° C. over 30 minutes, and 100 ml of 2N sodium hydroxide aqueous solution was added dropwise at 10 ° C. over 30 minutes. did. The precipitated white solid was separated by filtration, and 300 ml of toluene and 1,000 ml of brine were added to the filtrate and mixed. Thereafter, the mixture was allowed to stand to separate into an organic layer and an aqueous layer, and an extraction operation into the organic layer was performed. The obtained organic layer was separated, washed with brine, and dried over anhydrous magnesium sulfate. Thereafter, the solvent was distilled off under reduced pressure to obtain 152.7 g of colorless transparent liquid 2- (1,4-dioxaspiro [4,5] dec-8-yl) ethanol (13).

Fourth Step To a reactor under a nitrogen atmosphere, 150.0 g of compound (13), triphenylphosphine (
(Ph ₃ P) 274.3 g, 71.3 g of imidazole and 900 ml of toluene were added, and the mixture was stirred at 3 ° C. Thereto, 255.5 g of iodine was divided into 10 portions, added in a temperature range of 3 ° C. to 10 ° C., and further stirred at room temperature for 3 hours at 0 ° C. After confirming that the reaction was complete by GC analysis, the precipitated yellow solid was filtered off. The filtrate was concentrated, 400 ml of heptane was added to the resulting residue, and the precipitated pale yellow solid was separated by filtration. The filtrate was concentrated, and the resulting residue was purified by a preparative operation by column chromatography using toluene as a developing solvent and silica gel as a filler, and the solvent was distilled off under reduced pressure. 223.9 g of-(2-iodoethyl) -1,4-dioxaspiro [4,5] decane (14) was obtained.

Step 5 223.0 g of Compound (14) and 800 ml of DMF were added to a reactor under a nitrogen atmosphere, and the mixture was stirred at 3 ° C. under ice cooling. Potassium t-butoxide (t-BuOK) 92.9 there
g was divided into 10 portions and added in a temperature range of 3 ° C. to 10 ° C., and further stirred at 0 ° C. for 3 hours at room temperature. After confirming the completion of the reaction by GC analysis, the reaction mixture was poured into a mixture of 1,500 ml of heptane and 1,500 ml of water at 0 ° C. and mixed. Thereafter, the mixture was allowed to stand to separate into an organic layer and an aqueous layer, and an extraction operation into the organic layer was performed. The obtained organic layer was separated, washed with water, and dried over anhydrous magnesium sulfate. The resulting solution was purified by preparative operation by column chromatography using heptane as a developing solvent and silica gel as a filler, and the solvent was distilled off under reduced pressure. The obtained residue was distilled under reduced pressure to obtain 103.3 g of colorless and transparent liquid 8-vinyl-1,4-dioxaspiro [4,5] decane (15).

Step 6 To a reactor under a nitrogen atmosphere, 103.3 g of Compound (15), 86.5 g of 98% formic acid and 200 ml of toluene were added, heated and stirred for 2 hours under reflux. After confirming that the reaction was complete by GC analysis, the reaction mixture was poured into 500 ml of 0 ° C. saline and mixed. Thereafter, the mixture was allowed to stand to separate into an organic layer and an aqueous layer, and an extraction operation into the organic layer was performed. The obtained organic layer was separated, washed with saturated aqueous sodium hydrogen carbonate and brine, dried over anhydrous magnesium sulfate, and the solvent was evaporated under reduced pressure. The obtained residue was distilled under reduced pressure to obtain 66.7 g of a colorless transparent liquid 4-vinylcyclohexanone (16).

Seventh step 1.76 g of well-dried magnesium and 10 ml of THF were added to a reactor under a nitrogen atmosphere and heated to 53 ° C. Thereto, 17.2 g of the compound (1) dissolved in 30 ml of THF was slowly dropped in a temperature range of 50 ° C. to 56 ° C., and further stirred for 30 minutes. Thereafter, 6.0 g of Compound (16) dissolved in 10 ml of THF was slowly added dropwise in the temperature range of 50 ° C. to 55 ° C., and the mixture was further stirred for 30 minutes. The resulting reaction mixture was cooled to 25 ° C., and poured into a mixture of 100 ml of 1N hydrochloric acid and 100 ml of toluene and mixed. Then, it left still and was made to isolate | separate into an organic layer and a water layer, and extraction operation to an organic layer was performed. The obtained organic layer was separated, washed with water, 2N aqueous sodium hydroxide solution, saturated aqueous sodium hydrogen carbonate, and water, and dried over anhydrous magnesium sulfate. Thereafter, the solvent was distilled off under reduced pressure to obtain 18.5 g of 1- (4-ethoxy-2,3-difluorophenyl) -4-vinylcyclohexanol (17) as a yellow liquid.

Eighth Step Compound (17) 18.5 g, p-toluenesulfonic acid 0.4 g, and toluene 6
0 ml was mixed, and this mixture was heated to reflux for 1 hour while removing distilled water. After the reaction mixture was cooled to 25 ° C., 100 ml of water and 100 ml of toluene were added to and mixed with the resulting liquid. Then, it left still and isolate | separated into two layers, an organic layer and an aqueous layer, and extraction operation to the organic layer was performed. The obtained organic layer was separated, washed with 2N aqueous sodium hydroxide solution, saturated aqueous sodium bicarbonate, and water, and dried over anhydrous magnesium sulfate. Thereafter, the solvent was distilled off under reduced pressure to obtain a residue. The obtained residue was purified by preparative operation by column chromatography using a mixed solvent of heptane and toluene (volume ratio heptane: toluene = 3: 1) as a developing solvent and silica gel as a packing material. Purification by crystals and drying gave 2.58 g of white 1-ethoxy-2,3-difluoro-4- (4-vinylcyclohex-1-enyl) benzene (No. 12). The yield based on the compound (16) was 20.2%.

The transition temperature of compound (No. 12) obtained is as follows.
Transition temperature: C 22.6 I
The chemical shift δ (ppm) of ¹ H-NMR analysis is as follows, and the obtained compound is
It could be identified as 1-ethoxy-2,3-difluoro-4- (4-vinylcyclohex-1-enyl) benzene. The measurement solvent is CDCl ₃ .

  Chemical shift δ (ppm); 6.85 (td, 1H), 6.64 (td, 1H), 5.90-5.83 (m, 2H), 5.05 (dt, 1H), 4.97 (Dt, 1H) 4.08 (q, 2H), 2.48-2.27 (m, 4H), 2.06-2.00 (m, 1H), 1.93-1.88 (m, 1H), 1.56-1.49 (m, 1H), 1.42 (t, 3H).

The following compounds (No. 1) to (No. 360) can be synthesized by a method similar to the synthesis method described in Examples 1 to 5. The appended data follows the method described above,
It is a measured value. The transition temperature is a measured value of the compound itself, and the maximum temperature (T _NI ), dielectric anisotropy (Δε), and optical anisotropy (Δn) are measured in a sample in which the compound is mixed with the mother liquid crystal (i). An extrapolated value obtained by converting the value according to the extrapolation method.

[Comparative Example 1]
As a comparative example, synthesis of trans-4 ′-(4-ethoxy-2,3-difluorophenyl) -trans-4-ethylbicyclohexyl (F) in which the alkenyl group is an alkyl group and the cyclohexenylene group is a cyclohexyl group did.

The mother liquid crystal i having a nematic phase was prepared by mixing the five compounds described as the mother liquid crystal i described above. The physical properties of the mother liquid crystal i were as follows.
Maximum temperature (T _NI ) = 74.0 ° C .; viscosity (η ₂₀ ) = 18.9 mPa · s; optical anisotropy (Δn) = 0.087; dielectric anisotropy (Δε) = − 1.3.

A liquid crystal composition ii comprising 85% by weight of the mother liquid crystal i and 15% by weight of the synthesized trans-4 ′-(4-ethoxy-2,3-difluorophenyl) -trans-4-ethylbicyclohexyl (F). Was prepared. The physical property value of the obtained liquid crystal composition ii was measured, and the extrapolated value of the physical property of the comparative compound (F) was calculated by extrapolating the measured value. The values were as follows:
Maximum temperature (T _NI ) = 129.3 ° C .;
Optical anisotropy (Δn) = 0.105;
Dielectric anisotropy (Δε) = − 5.92;
Viscosity (η) = 46.2 mPa · s
Further, the elastic constant K ₃₃ of the liquid crystal composition ii was 15.58 pN.

Furthermore, when this liquid crystal composition ii was stored in a freezer at −10 ° C. for 30 days, the liquid crystal composition ii was crystallized.
[Comparative Example 2]
As a comparative example, trans-4 ′-(4-ethoxy-2,3-difluorophenyl) -trans-4-vinylbicyclohexyl (G) having an alkenyl group and a cyclohexenylene group being a cyclohexyl group was synthesized.

A liquid crystal composition iii comprising 85% by weight of the base liquid crystal i and 15% by weight of the synthesized trans-4 ′-(4-ethoxy-2,3-difluorophenyl) -trans-4-vinylbicyclohexyl (G) Prepared. The physical property value of the obtained liquid crystal composition iii was measured, and the extrapolated value of the physical property of the comparative compound (G) was calculated by extrapolating the measured value. The values were as follows:
Maximum temperature (T _NI ) = 141.9 ° C .;
Optical anisotropy (Δn) = 0.111;
Dielectric anisotropy (Δε) = − 5.59;
Viscosity (η) = 38.5 mPa · s
The elastic constant K ₃₃ of the liquid crystal composition iii was 15.15 pN.

[Comparative Example 3]
As a comparative example, trans-4- (4-ethoxy-2,3-difluorophenyl) -trans-4′-ethylbicyclohexyl-3-ene (H) having alkenyl and a cyclohexenylene group being a cyclohexyl group Synthesized.

A liquid crystal comprising 85% by weight of the mother liquid crystal i and 15% by weight of the synthesized trans-4- (4-ethoxy-2,3-difluorophenyl) -trans-4′-ethylbicyclohexyl-3-ene (H). Composition iv was prepared. The physical property value of the obtained liquid crystal composition iv was measured, and the extrapolated value of the physical property of the comparative compound (H) was calculated by extrapolating the measured value. The values were as follows:
Maximum temperature (T _NI ) = 132.6 ° C .;
Optical anisotropy (Δn) = 0.128;
Dielectric anisotropy (Δε) = − 6.1;
Viscosity (η) = 47.7 mPa · s
The elastic constant K ₃₃ of the liquid crystal composition iv was 15.2 pN.

  Further, when the liquid crystal composition iv was stored in a freezer at −10 ° C. for 30 days, the liquid crystal composition iv was crystallized.

Physical properties of liquid crystal compound (No. 132): 85% by weight of mother liquid crystal i and 4- (4-ethoxy-2,3-difluorophenyl) -trans-4′-vinylbicyclohexyl-3 obtained in Example 1 -En (No. 132)
A liquid crystal composition v consisting of 15% by weight of was prepared. The physical property value of the obtained liquid crystal composition v was measured, and the extrapolated value of the physical property of the liquid crystal compound (No. 132) was calculated by extrapolating the measured value. The values were as follows:
Maximum temperature (T _NI ) = 143.9 ° C .;
Optical anisotropy (Δn) = 0.141;
Dielectric anisotropy (Δε) = − 6.03;
Viscosity (η) = 38.7 mPa · s
The elastic constant K ₃₃ of the liquid crystal composition v was 16.12 pN.

Further, when this liquid crystal composition v was stored in a freezer at −10 ° C. for 30 days, the liquid crystal composition v remained in a nematic phase.
Therefore, the liquid crystalline compound (No. 132) has a high maximum temperature (T _NI ), a large optical anisotropy (Δn), and a negative dielectric anisotropy (Δε) which can be negatively increased. It was found that the compound was excellent in compatibility with other liquid crystalline compounds.

Further, compared with Comparative Example Compound (F) and Comparative Example Compound (H), although the dielectric anisotropy (Δε) is equivalent, the upper limit temperature (T _NI ) of the nematic phase is high and the viscosity (η ) With small optical anisotropy (Δn) and large elastic constant K ₃₃ .

Furthermore, although the upper limit temperature (T _NI ) and viscosity (η) of the nematic phase are equivalent as compared with the comparative compound (G), the dielectric anisotropy is negatively large and the optical anisotropy (Δn ) and it was found to be large compound elastic constant K _33.

[Comparative Example 4]
As a comparative example, synthesis of trans-4 ′-(4-ethoxy-2,3-difluorophenyl) -trans-4-propylbicyclohexyl (I) in which the alkenyl group is an alkyl group and the cyclohexenylene group is a cyclohexyl group did.

A liquid crystal composition vi comprising 85% by weight of the mother liquid crystal i and 15% by weight of the synthesized trans-4 ′-(4-ethoxy-2,3-difluorophenyl) -trans-4-propylbicyclohexyl (I) Prepared. The physical property value of the obtained liquid crystal composition vi was measured, and the extrapolated value of the physical property of the comparative compound (I) was calculated by extrapolating the measured value. The values were as follows:
Maximum temperature (T _NI ) = 159.9 ° C .;
Optical anisotropy (Δn) = 0.112;
Dielectric anisotropy (Δε) = − 5.32;
Viscosity (η) = 41.0 mPa · s
Further, when the liquid crystal composition vi was stored in a freezer at −10 ° C. for 30 days, the liquid crystal composition vi was crystallized.

[Comparative Example 5]
As a comparative example, trans-4 ′-(4-ethoxy-2,3-difluorophenyl) -trans-4-propenylbicyclohexyl (J) having an alkenyl group and a cyclohexenylene group being a cyclohexyl group was synthesized.

A liquid crystal composition vii comprising 85% by weight of the mother liquid crystal i and 15% by weight of the synthesized trans-4 ′-(4-ethoxy-2,3-difluorophenyl) -trans-4-propenylbicyclohexyl (J) was prepared. Prepared. The physical property value of the obtained liquid crystal composition vii was measured, and the extrapolated value of the physical property of the comparative compound (J) was calculated by extrapolating the measured value. The values were as follows:
Maximum temperature (T _NI ) = 175.3 ° C .;
Optical anisotropy (Δn) = 0.132;
Dielectric anisotropy (Δε) = − 5.44;
Viscosity (η) = 44.8 mPa · s
Further, when the liquid crystal composition vii was stored in a freezer at −10 ° C. for 30 days, the liquid crystal composition vii was crystallized.

[Comparative Example 6]
As a comparative example, trans-4- (4-ethoxy-2,3-difluorophenyl) -trans-4′-propylbicyclohexyl-3-ene (K) having an alkenyl group and the cyclohexenylene group being a cyclohexyl group Was synthesized.

A liquid crystal comprising 85% by weight of the mother liquid crystal i and 15% by weight of the synthesized trans-4- (4-ethoxy-2,3-difluorophenyl) -trans-4′-propylbicyclohexyl-3-ene (K). Composition viii was prepared. The physical property value of the obtained liquid crystal composition viii was measured, and the extrapolated value of the physical property of the comparative compound (K) was calculated by extrapolating the measured value. The values were as follows:
Maximum temperature (T _NI ) = 157.3 ° C .;
Optical anisotropy (Δn) = 0.140;
Dielectric anisotropy (Δε) = − 6.28;
Viscosity (η) = 37.8 mPa · s
Further, when the liquid crystal composition viii was stored in a freezer at −10 ° C. for 30 days, the liquid crystal composition viii was crystallized.

Physical properties of liquid crystal compound (No. 152): 85% by weight of mother liquid crystal i and 4- (4-ethoxy-2,3-difluorophenyl) -trans-4′-propenylbicyclohexyl-3 obtained in Example 2 -En (No. 1
A liquid crystal composition ix consisting of 15% by weight of 52) was prepared. The physical property value of the obtained liquid crystal composition ix was measured, and the extrapolated value of the physical property of the liquid crystal compound (No. 152) was calculated by extrapolating the measured value. The values were as follows:
Maximum temperature (T _NI ) = 173.3 ° C .;
Optical anisotropy (Δn) = 0.164;
Dielectric anisotropy (Δε) = − 6.48;
Viscosity (η) = 42.59 mPa · s
Therefore, the liquid crystalline compound (No. 152) is a compound having a high maximum temperature (T _NI ), a large optical anisotropy (Δn), and a negative dielectric anisotropy (Δε). I found out.

Also, a compound having a high maximum temperature (T _NI ), a large dielectric anisotropy (Δε), and a large optical anisotropy (Δn) as compared with Comparative Compounds (I) and (K) I found out that

Compared with Comparative Example Compound (J), the maximum temperature (T _NI ) and viscosity (η) are almost the same, but the compound has a large negative dielectric anisotropy (Δε) and a large optical anisotropy (Δn). I found out that

Low-temperature compatibility of liquid crystal compound (No. 172) Mother liquid crystal i 85% by weight and trans-4′-but-3-enyl-4- described in Example 6
(4-Ethoxy-2,3-difluorophenyl) bicyclohexyl-3-ene (No
. A liquid crystal composition x consisting of 15% by weight of 172) was prepared. When this liquid crystal composition x was stored in a freezer at −10 ° C. for 30 days, the liquid crystal composition x remained in a nematic phase. From this, it was found that the liquid crystal compound (No. 172) was excellent in compatibility with other liquid crystal compounds at low temperatures.

Low-temperature compatibility of the liquid crystal compound (No. 212) 85% by weight of the mother liquid crystals i and 4- (4-ethoxy-2,3-difluorophenyl) -trans-4′-pent-4- described in Example 6 Enylbicyclohexyl-3-ene (N
o. A liquid crystal composition xi consisting of 15% by weight of 212) was prepared. When this liquid crystal composition xi was stored in a freezer at −10 ° C. for 30 days, the liquid crystal composition xi remained in a nematic phase. From this, it was found that the liquid crystal compound (No. 212) was a compound having excellent compatibility with other liquid crystal compounds at low temperatures.

[Examples of liquid crystal composition]
Hereinafter, the liquid crystal composition obtained by the present invention will be described in detail with reference to examples. The liquid crystalline compounds used in the examples are represented by symbols based on the definitions in Table 1 below. In Table 1, the configuration of 1,4-cyclohexylene is a trans configuration. The ratio (percentage) of each compound is a weight percentage (% by weight) based on the total weight of the liquid crystal composition unless otherwise specified. The characteristic values of the liquid crystal composition obtained at the end of each example are shown.

In addition, the number described in the portion of the liquid crystal compound used in each example corresponds to the formula number indicating the liquid crystal compound used for the first to third components of the present invention described above.
The notation method by the symbol of a compound is shown below.

The characteristic values were measured according to the following method. Many of these measurement methods are based on the Standard of Electric Industries Association of Japan EIAJ / E.
The method described in D-2521A, or a modified method thereof.

(1) Maximum temperature of nematic phase (NI; ° C)
A sample was placed on a hot plate of a melting point measurement apparatus equipped with a polarizing microscope and heated at a rate of 1 ° C./min. The temperature was measured when a part of the sample changed from a nematic phase to an isotropic liquid. Hereinafter, the upper limit temperature of the nematic phase may be abbreviated as “upper limit temperature”.

(2) Minimum temperature of nematic phase (TC; ° C)
A sample having a nematic phase was stored in a freezer at 0 ° C., −10 ° C., −20 ° C., −30 ° C., and −40 ° C. for 10 days, and then the liquid crystal phase was observed. For example, when the sample remained in a nematic phase at −20 ° C. and changed to a crystal or smectic phase at −30 ° C., TC was described as ≦ −20 ° C. Hereinafter, the lower limit temperature of the nematic phase may be abbreviated as “lower limit temperature”.

(3) Optical anisotropy (Δn; measured at 25 ° C.)
Measurement was performed using an Abbe refractometer with a polarizing plate attached to the eyepiece using light having a wavelength of 589 nm. First, after rubbing the surface of the main prism in one direction, the sample was dropped on the main prism. Then, the refractive index (n‖) when the polarization direction was parallel to the rubbing direction and the refractive index (n⊥) when the polarization direction was perpendicular to the rubbing direction were measured. The value of optical anisotropy (Δn) is
(Δn) = (n∥) − (n∥)
It was calculated from the formula of

(4) Viscosity (η; measured at 20 ° C .; mPa · s)
An E-type viscometer was used for the measurement.
(5) Dielectric anisotropy (Δε; measured at 25 ° C.)
An ethanol (20 mL) solution of octadecyltriethoxysilane (0.16 mL) was applied to a well-cleaned glass substrate. The glass substrate was rotated with a spinner and then heated at 150 ° C. for 1 hour. A VA device having an interval (cell gap) of 20 μm was assembled from two glass substrates. In the same manner, a polyimide alignment film was prepared on a glass substrate. After the alignment film of the obtained glass substrate was rubbed, a TN device in which the distance between the two glass substrates was 9 μm and the twist angle was 80 degrees was assembled. A sample (a liquid crystal composition or a mixture of a liquid crystal compound and a mother liquid crystal) is placed in the obtained VA element, 0.5 V (1 kHz, sine wave) is applied, and the dielectric constant ( ε‖) was measured. In addition, a sample (a liquid crystal composition or a mixture of a liquid crystal compound and a mother liquid crystal) is put into the obtained TN device, 0.5 V (1 kHz, sine wave) is applied, and the dielectric in the minor axis direction of the liquid crystal molecules The rate (ε⊥) was measured. The value of dielectric anisotropy was calculated from the equation: Δε = ε∥−ε⊥.

(6) Voltage holding ratio (VHR; measured at 25 ° C. and 100 ° C .;%)
A sample was put in a cell having a polyimide alignment film and a distance (cell gap) between two glass substrates of 6 μm to produce a TN device. At 25 ° C., the TN device was charged by applying a pulse voltage (5 V, 60 microseconds). The waveform of the voltage applied to the TN device was observed with a cathode ray oscilloscope, and the area between the voltage curve and the horizontal axis in a unit cycle (16.7 milliseconds) was determined. The area was similarly determined from the waveform of the voltage applied after removing the TN element. The value of the voltage holding ratio (%) was calculated from the value of (voltage holding ratio) = (area value when there is a TN element) / (area value when there is no TN element) × 100.

The voltage holding ratio thus obtained is indicated as “VHR-1”. Next, this TN device was heated at 100 ° C. for 250 hours. After returning the TN device to 25 ° C., the voltage holding ratio was measured by the same method as described above. The voltage holding ratio obtained after this heating test was shown as “VHR-2”. This heating test is an accelerated test, and was used as a test corresponding to the long-term durability test of the TN device.

V-ChB (2F, 3F) -1 (No. 1) 10%
V-ChB (2F, 3F) -O2 (No. 12) 11%
V-ChB (2F, 3F) -O4 (No. 14) 11%
V-HChB (2F, 3F) -1 (No. 121) 10%
V-HChB (2F, 3F) -O2 (No. 132) 10%
V-HChB (2F, 3F) -O4 (No. 134) 11%
2-HH-5 (2-1) 10%
3-HB-O2 (2-4) 15%
3-HHEBH-3 (2-74) 7%
3-HHEBH-5 (2-74) 5%
NI = 76.4 ° C .; TC ≦ −20 ° C .; Δn = 0.100; η = 21.1 mPa · s; Δε = −3.2.

1V-ChB (2F, 3F) -1 (No. 21) 12%
1V-ChB (2F, 3F) -O2 (No. 32) 12%
1V-ChB (2F, 3F) -O4 (No. 34) 12%
1V-HChB (2F, 3F) -O2 (No. 152) 10%
1V-HChB (2F, 3F) -O4 (No. 154) 10%
3-HH-4 (2-1) 10%
3-HB-O2 (2-4) 16%
3-HHEH-3 (2-46) 5%
3-HHEH-5 (2-46) 5%
5-HBB (3F) B-2 (2-73) 8%
NI = 84.2 ° C .; Δn = 0.113; η = 25.8 mPa · s; Δε = −3.0.

V-ChB (2F, 3F) -O2 (No. 12) 11%
V-ChB (2F, 3F) -O4 (No. 14) 11%
1V-ChB (2F, 3F) -O2 (No. 32) 11%
V-HChB (2F, 3F) -1 (No. 121) 10%
V-HChB (2F, 3F) -O2 (No. 132) 8%
V-HChB (2F, 3F) -O4 (No. 134) 7%
1V-HChB (2F, 3F) -O2 (No. 152) 8%
1V-HChB (2F, 3F) -O4 (No. 154) 7%
5-HH-V (2-1) 22%
V-HHB-1 (2-25) 5%
NI = 74.1 ° C .; Δn = 0.102; η = 21.4 mPa · s; Δε = −4.0.

V-ChB (2F, 3F) -O4 (No. 14) 10%
1V-ChB (2F, 3F) -O2 (No. 32) 10%
1V-ChB (2F, 3F) -O4 (No. 34) 10%
V-HChB (2F, 3F) -O2 (No. 132) 10%
V-HChB (2F, 3F) -O4 (No. 134) 10%
3-HH-V1 (2-1) 10%
3-HH-O1 (2-1) 10%
V-HHB-1 (2-25) 5%
3-HHB-O1 (2-25) 5%
3-HBB-2 (2-35) 5%
2-BB (3F) B-3 (2-44) 5%
2-BB (3F) B-5 (2-44) 5%
V2-BB (3F) B-1 (2-44) 5%
NI = 79.3 ° C .; Δn = 0.126; η = 22.1 mPa · s; Δε = −3.0.

V-ChB (2F, 3F) -O2 (No. 12) 10%
1V-ChB (2F, 3F) -O2 (No. 32) 10%
1V-ChB (2F, 3F) -O4 (No. 34) 10%
V-HChB (2F, 3F) -O2 (No. 132) 10%
V-HChB (2F, 3F) -O4 (No. 134) 10%
1V-HChB (2F, 3F) -O2 (No. 152) 10%
3-HH-O1 (2-1) 10%
5-HB-3 (2-4) 5%
3-HB-O1 (2-4) 10%
3-HHB-1 (2-25) 5%
3-HHEH-3 (2-46) 5%
3-HHEBH-3 (2-74) 5%
NI = 77.6 ° C .; Δn = 0.099; η = 24.7 mPa · s; Δε = −3.5.

Claims (16)

A liquid crystal compound selected from the group of compounds represented by the following formula (a).

(Wherein, Ra, and Rb are independently hydrogen, alkyl having 1 to 10 carbons, or alkenyl having 2 to 10 carbon atoms, in the in the above alkyl, -CH ₂ - in -O- May be replaced, but -O- is not consecutive and hydrogen may be replaced by fluorine;
Ring A ¹ and Ring A ² are independently trans-1,4-cyclohexylene, or 1,4-phenylene in which one or two hydrogens on the ring may be replaced by halogen. In the 6-membered ring, one —CH ₂ — or two non-adjacent —CH ₂ — may be replaced by —O—, and one or two —CH═ is —N═. Each may be replaced;
Z ¹ and Z ² are each independently a single bond, — (CH ₂ ) ₂ —, — (CH ₂ ) ₄ —, —CH═CH—, —C≡C—, —CH ₂ O—, — OCH ₂ —, —COO—, —OCO—, or —OCF ₂ —;
l and m are independently 0, 1, or 2, but l + m is 0, 1, 2, or 3;
n is an integer of 0 to 6, and —CH ₂ — in — (CH ₂ ) n — may be replaced with —O—, but —O— is not continuous, and hydrogen is replaced with fluorine. It may be done. ) In the above formula (a), ring A ¹ and ring A ² are independently trans-1,4-cyclohexylene or 1,4-phenylene;
Z ¹ and Z ² are a single bond;
l + m is 0 or 1;
The compound according to claim 1, wherein n is an integer of 0 to 6. In the above formula (a), Ra is hydrogen or alkyl having 1 to 10 carbons;
The compound according to claim 2, wherein Rb is alkoxy having 1 to 9 carbon atoms.   The compound according to claim 3, wherein, in the formula (a), l + m is 1.   A liquid crystal composition comprising at least one of the compounds according to claim 1. A first component comprising at least one compound selected from the compound group described in any one of claims 1 to 4, a formula (e-1), a formula (e-2), and a formula (e) A liquid crystal composition having a negative dielectric anisotropy, comprising a second component comprising at least one compound selected from the compound group consisting of 3).

(In the formula, Ra ₁₁ and Rb ₁₁ are each independently an alkyl having 1 to 10 carbon atoms. In the alkyl, —CH ₂ — that is not adjacent to each other may be replaced by —O—. The non-adjacent — (CH ₂ ) ₂ — may be replaced with —CH═CH— and the hydrogen may be replaced with fluorine;
Ring A ¹¹ , Ring A ¹² , Ring A ¹³ and Ring A ¹⁴ are independently trans-1,4-cyclohexylene, 1,4-phenylene, 2-fluoro-1,4-phenylene, 3- Fluoro-1,4-phenylene, pyrimidine-2,5-diyl, 1,3-dioxane-2,5-diyl, or tetrahydropyran-2,5-diyl;
Z ¹¹ , Z ¹² , and Z ¹³ are each independently a single bond, —CH ₂ —CH ₂ —, —CH═CH—, —C≡C—, —COO—, or —CH ₂ O—. . )   A first component comprising at least one compound selected from the group of compounds according to claim 3 and formula (e-1), formula (e-2), and formula (e-3) according to claim 6 A liquid crystal composition having a negative dielectric anisotropy, comprising a second component comprising at least one compound selected from the group of compounds represented by:   The content ratio of the first component is in the range of 30 to 85% by weight and the content ratio of the second component is in the range of 15 to 70% by weight based on the total weight of the liquid crystal composition. The liquid crystal composition described in 1. In addition to the first component and the second component, selected from the compound group represented by the following formula (g-1), formula (g-2), formula (g-3), and formula (g-4) The liquid crystal composition according to claim 6 or 7, comprising a third component comprising at least one compound.

(In the formula, Ra ₂₁ and Rb ₂₁ are independently hydrogen or alkyl having 1 to 10 carbons, but in the alkyl, —CH ₂ — that is not adjacent to each other is replaced by —O—. Or — (CH ₂ ) ₂ — that are not adjacent to each other may be replaced by —CH═CH—, and hydrogen may be replaced by fluorine;
Ring A ²¹ , Ring A ²² , and Ring A ²³ are independently trans-1,4-cyclohexylene, 1,4-phenylene, 2-fluoro-1,4-phenylene, 3-fluoro-1, 4-phenylene, 2,3-difluoro-1,4-phenylene, pyrimidine-2,5-diyl, 1,3-dioxane-2,5-diyl, or tetrahydropyran-2,5-diyl;
Z ²¹ , Z ²² and Z ²³ are each independently a single bond, —CH ₂ —CH ₂ —, —CH═CH—, —C≡C—, —OCF ₂ —, —CF ₂ O—, — _{OCF 2 CH 2 CH 2 -,} - CH 2 CH 2 CF 2 O -, - COO -, - OCO -, - OCH 2 -, or -CH ₂ O-;
Y ¹ , Y ² , Y ³ , and Y ⁴ are independently fluorine or chlorine;
q, r, and s are independently 0, 1, or 2, but q + r + s is 1, 2, or 3;
t is 0, 1, or 2. ) The third component is selected from the group of compounds represented by the following formula (h-1), formula (h-2), formula (h-3), formula (h-4), and formula (h-5) The liquid crystal composition according to claim 9, comprising at least one compound.

(In the formula, Ra ₂₂ is linear alkyl having 1 to 8 carbons or linear alkenyl having 2 to 8 carbons;
Rb ₂₂ is a straight-chain alkyl having 1 to 8 carbon atoms, a straight chain alkenyl, or alkoxy having 1 to 7 carbon atoms of 2 to 8 carbon atoms;
Z ²⁴ is a single bond or —CH ₂ CH ₂ —;
Y ¹ and Y ² are both fluorine, or one is fluorine and the other is chlorine. )   A first component comprising at least one compound selected from the group of compounds described in claim 3, and a formula (e-1), a formula (e-2), and a formula (e- A second component comprising at least one compound selected from the group of compounds represented by 3), and the formula (h-1), formula (h-2), and formula (h-3) according to claim 10 A liquid crystal composition having a negative dielectric anisotropy, comprising a third component comprising at least one compound selected from the group of compounds represented by formulas (h-4) and (h-5):   Based on the total weight of the liquid crystal composition, the content of the first component is in the range of 10 to 80% by weight, the content of the second component is in the range of 10 to 80% by weight, and the third The liquid crystal composition according to claim 9, wherein the content ratio of the components is in the range of 10 to 80% by weight.   Furthermore, the liquid-crystal composition of any one of Claims 5-12 containing antioxidant and / or a ultraviolet absorber. The liquid crystal composition according to claim 13, comprising an antioxidant represented by the following formula (I).

(In the above formula (I), w represents an integer of 1 to 15)   The liquid crystal display element containing the liquid-crystal composition of any one of Claims 5-14.   The liquid crystal display element according to claim 15, wherein an operation mode of the liquid crystal display element is a VA mode or an IPS mode, and a driving method of the liquid crystal display element is an active matrix method.