JP5077621B2 - Difluorobenzene derivative and liquid crystal composition using the same - Google Patents

Description

  The present invention relates to a nematic liquid crystal composition having a negative dielectric anisotropy Δε useful as an electro-optical liquid crystal display material, and a liquid crystal display device using the same.

  The liquid crystal display element is used in various electric appliances for home use, measuring instruments, automobile panels, word processors, electronic notebooks, printers, computers, televisions, etc., including clocks and calculators. Typical liquid crystal display methods include TN (twisted nematic), STN (super twisted nematic), DS (dynamic light scattering), GH (guest / host), and IPS (in-plane switching). Type, OCB (optical compensation birefringence) type, ECB (voltage controlled birefringence) type, VA (vertical alignment) type, CSH (color super homeotropic) type, FLC (ferroelectric liquid crystal), etc. . As a driving method, multiplex driving is generally used instead of conventional static driving, and the active matrix (AM) method driven by a TFT (thin film transistor), TFD (thin film diode) or the like has become mainstream recently. ing.

  In these display systems, the IPS type, ECB type, VA type, CSH type and the like have a feature that a liquid crystal material having a negative dielectric anisotropy (Δε) is used, unlike currently-used TN type and STN type. . Among these, VA type display by AM driving is currently most expected in application to a display element that requires a high speed and a wide viewing angle, such as a television.

A liquid crystal material used in a display method such as a VA type is required to have low voltage driving, high speed response, and a wide operating temperature range. That is, the dielectric anisotropy is negative, the absolute value is large, the viscosity is low, and a high nematic phase-isotropic liquid phase transition temperature (Tni) is required. Moreover, it is necessary to adjust the refractive index anisotropy of the liquid crystal material to an appropriate range according to the cell gap from the setting of Δn × d, which is the product of the refractive index anisotropy (Δn) and the cell gap (d). is there. In order to realize a high-speed response, the cell gap of the display element is reduced, but there is a limit to narrowing the cell gap due to the above-described restrictions. In order to improve the response speed without changing the cell gap, it is effective to use a liquid crystal composition having a low viscosity. In the case of applying a liquid crystal display element to a television or the like, since high-speed response is important, development of a liquid crystal composition having particularly low viscosity has been demanded.
As liquid crystal materials having a negative dielectric anisotropy, the following liquid crystal compounds having a 2,3-difluorophenylene skeleton (see Patent Documents 1 and 2) are disclosed.

(In the formula, R and R ′ represent an alkyl group having 1 to 10 carbon atoms or an alkoxy group.)
Furthermore, these references include compounds having a 1-hydroxy-2,3-difluoro-4-substituted benzene skeleton, which is the basic skeleton of the liquid crystal compound constituting the present invention. However, the compounds described in the cited document are wide, and there is no specific disclosure regarding compounds having alkenyl groups in both side chains, and liquid crystal compositions having a negative dielectric anisotropy using the described compounds. The product has not yet achieved a sufficiently low viscosity in a liquid crystal composition that requires a high-speed response such as a liquid crystal television.

  On the other hand, there is also a disclosure of a liquid crystal composition using a compound having a 1-hydroxy-2,3-difluoro-4-substituted benzene skeleton, which is a basic skeleton of a liquid crystal compound constituting the present invention (Patent Document 3, Patent Document 3). 4 and Patent Document 5), there is no specific description of a liquid crystal composition using a compound having an alkenyl group in both side chains, and the viscosity of the liquid crystal composition can be determined by using the compound and any other compound. There is no specific disclosure about whether or not it can be reduced.

  In addition, a liquid crystal compound having a 2,3-difluorohydroquinone skeleton has already been disclosed (see Patent Documents 6 and 7), and a liquid crystal composition using the compound is also disclosed. However, since the compound has a hydroquinone skeleton, it is considered that it cannot be used for an active matrix in terms of voltage holding ratio (see Non-Patent Document 1). A low-viscosity liquid crystal composition for VA using the compound. The development of things was delayed.

  As a liquid crystal compound having a negative dielectric anisotropy value and a large absolute value, a liquid crystal compound having a 7,8-difluorochroman skeleton (see Patent Document 8) is disclosed. However, although this compound and a liquid crystal composition using the same have a negative dielectric anisotropy value and a large absolute value, it cannot be said that the viscosity is sufficiently low, and the liquid crystal compound and the liquid crystal composition have a lower viscosity. There was a need to develop things.

Some liquid crystal compounds having a low viscosity have an alkenyl group in the side chain, and general disclosure including many compounds has already been made (see Patent Document 9). However, the cited document is intended to use a liquid crystal compound and a liquid crystal composition having a positive dielectric anisotropy value, and as a liquid crystal composition having a negative dielectric anisotropy value, which compound in a wide disclosure range is specified. There is no disclosure of what compounds are used together and what effects are used in combination.
Accordingly, development of a liquid crystal composition having a negative dielectric anisotropy and a low viscosity has been desired.

JP-A-60-199840 JP-A-2-4725 JP-A-8-104869 JP 2000-96055 A European Patent Application No. 04744062 (page 14) Special table 2-503568 German Patent Application Publication No. 3,906,058 International Publication No. 2005/000995 Pamphlet JP 10-45639 A Numata Hiroshi, Monthly Display, Vol. 4, no. 3 pp. 1-7, (1998) (table 4 on page 5)

  The problem to be solved by the present invention is to provide a liquid crystal composition having a negative absolute dielectric anisotropy having a large absolute value and a low viscosity without reducing or increasing the refractive index anisotropy. . Furthermore, the problem to be solved by the present invention is to provide a difluorobenzene derivative having a negative dielectric constant anisotropy and a low viscosity, which is a constituent member of the liquid crystal composition, such as a VA type using the liquid crystal composition. The object is to provide a liquid crystal display element.

  As a result of intensive studies to solve the above-mentioned problems, the present invention has the general formula (I)

（式中、R¹は炭素数1から10のアルキル基又は炭素数2から10のアルケニル基を表し、これらの基中に存在する1個のCH₂基又は隣接していない2個以上のCH₂基はO及び/又はSに置換されてもよく、またこれらの基中に存在する1個又は2個以上の水素原子はF又はClに置換されてもよく、R²は炭素数1から10のアルキル基、炭素数1から10のアルコキシル基、炭素数2から10のアルケニル基又は炭素数3から10のアルケニルオキシ基を表し、
mは0、1又は2表す。）
で表される化合物を１種又は２種以上含有し、
第二成分として、一般式（II）

(In the formula, R ¹ represents an alkyl group having 1 to 10 carbon atoms or an alkenyl group having 2 to 10 carbon atoms, and one CH ₂ group present in these groups or two or more non-adjacent CHs. _Two groups may be substituted with O and / or S, and one or more hydrogen atoms present in these groups may be substituted with F or Cl, and R ² has 1 to Represents an alkyl group having 10 carbon atoms, an alkoxyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, or an alkenyloxy group having 3 to 10 carbon atoms,
m represents 0, 1 or 2. )
Containing one or more compounds represented by:
As the second component, the general formula (II)

(Wherein R ³ and R ⁴ each independently represent the same meaning as R ² in formula (I),
B ¹ and B ² are each independently
(a) trans-1,4-cyclohexylene group (two CH ₂ groups not one CH ₂ group or adjacent present in this group may be substituted with an oxygen atom or a sulfur atom)
(b) 1,4-phenylene group (one or more CH groups present in this group may be substituted with a nitrogen atom)
(c) 1,4-cyclohexenylene group, 1,4-bicyclo [2.2.2] octylene group, piperidine-1,4-diyl group, naphthalene-2,6-diyl group, decahydronaphthalene-2,6 Represents a group selected from the group consisting of a -diyl group and a 1,2,3,4-tetrahydronaphthalene-2,6-diyl group, and the group (a), the group (b) or the group (c) is CN or May be substituted with halogen,
Y ¹ and Y ² are independently
-CH ₂ CH _2- , -CH = CH-, -CH (CH ₃ ) CH _2- , -CH ₂ CH (CH ₃ )-, -CH (CH ₃ ) CH (CH ₃ )-, -CF ₂ CF _2- , -CF = CF-, -CH ₂ O-, -OCH _2- , -OCH (CH ₃ )-, -CH (CH ₃ ) O-,-(CH ₂ ) ₄ -,-(CH ₂ ) _{3 O -, - O (CH} 2) 3 -, - C≡C -, - CF 2 O -, - OCF 2 -, - COO -, - OCO -, - COS -, - SCO- or a single bond ,
When there are a plurality of Y ² and B ² , they may be the same or different,
p represents 0, 1 or 2. )
A nematic liquid crystal composition having a negative dielectric anisotropy containing one or more compounds represented by general formula (I-1), which is a constituent member of the liquid crystal composition

(In the formula, R ^a represents a linear alkenyl group having 2 to 7 carbon atoms, and R ^b represents a linear alkyl group having 1 to 7 carbon atoms or a linear alkenyl group having 2 to 7 carbon atoms. P1 and p2 each independently represents 1 or 2, and the sum of p1 and p2 is 3 or less), and a liquid crystal using the liquid crystal composition A display element is provided.

By the combination of the liquid crystal compounds of the present invention, a liquid crystal composition having a low viscosity and a negative dielectric anisotropy was obtained while the refractive index anisotropy was substantially maintained. By using this composition, a highly reliable liquid crystal display element capable of maintaining a high voltage holding ratio up to a high temperature range is provided, and this display is very practical as a liquid crystal display of VA mode, ECB mode, IPS mode, etc. In particular, it is effective for high-speed response without reducing the cell gap.
The difluorobenzene derivative of the present invention is useful as a component of the liquid crystal composition of the present invention because of its negative dielectric anisotropy and low viscosity.

In the liquid crystal composition of the present invention, the first component contains one or more compounds represented by the general formula (I), preferably 1 to 20 types, more preferably 1 to 15 types. 1 to 10 species are more preferred, and 2 to 8 species are particularly preferred.
The content of the compound represented by the general formula (I) is preferably in the range of 10 to 80% by mass, and more preferably in the range of 15 to 70% by mass. These compounds have a negative dielectric anisotropy with a large absolute value, but if the content is large, there is a tendency to increase the viscosity, or the smectic-nematic phase transition temperature may be increased. When importance is attached to low viscosity, or when importance is attached to low smectic-nematic phase transition temperature, these contents are preferably small. When importance is attached to negative dielectric anisotropy having a large absolute value, these contents are preferred. It is preferable that there are many.

In the general formula (I), R ¹ and R ² represent an alkyl group having 1 to 10 carbon atoms or an alkenyl group having 2 to 10 carbon atoms, and at least ^one of R ^{1 and} R ² is from 2 carbon atoms The alkenyl group preferably represents 10 alkenyl groups, and specifically the following structures are particularly preferable as the alkenyl group.

(構造式は右端で環に連結しているものとする。)
又、mは0又は1を表すことが好ましい。
更に詳述すると、一般式（I）は、具体的な構造として以下の一般式（I-A）及び一般式（I-B）で表される化合物が好ましく、

(The structural formula shall be connected to the ring at the right end.)
M preferably represents 0 or 1.
More specifically, the general formula (I) is preferably a compound represented by the following general formula (IA) or general formula (IB) as a specific structure,

(In the formula, R ⁵ , R ⁶ , R ⁷ and R ⁸ represent the same meaning as R ² in the general formula (I).)
Compounds represented by the group consisting of general formulas (IAI) to (IA-VIII) and general formulas (IBI) to (IB-IV) are more preferable.

(In the formula, R ⁵ , R ⁶ and R ⁸ represent an alkyl group having 1 to 10 carbon atoms or an alkenyl group having 2 to 10 carbon atoms.)
As the second component, the compound represented by the general formula (II) contains one or two or more kinds, preferably 1 to 12 kinds, more preferably 1 to 8 kinds, more preferably 2 to 6 kinds. Further preferred.

  The content of the general formula (II) is preferably in the range of 20 to 70% by mass, and more preferably in the range of 25 to 65% by mass. These compounds have little effect of increasing the absolute value of the dielectric anisotropy, but have the effect of lowering the viscosity. When importance is attached to increasing the absolute value of the property, it is preferable that these contents are small.

In general formula (II), R ³ and R ⁴ are each independently an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an alkoxyl group having 1 to 10 carbon atoms, or 3 to 10 carbon atoms. R ³ represents an alkyl group having 1 to 10 carbon atoms or an alkenyl group having 2 to 10 carbon atoms, R ⁴ represents an alkyl group having 1 to 10 carbon atoms, and 1 to carbon atoms. More preferably, it represents 10 alkoxyl groups or alkenyl groups having 2 to 10 carbon atoms,
Specifically, R ³ is -CH ₃ , -CH ₂ CH ₃ ,-(CH ₂ ) ₂ CH ₃ ,-(CH ₂ ) ₃ CH ₃ ,-(CH ₂ ) ₄ CH ₃ ,-(CH ₂ ) ₅ CH ₃ ,-(CH ₂ ) ₆ CH ₃ ,-(CH ₂ ) ₇ CH ₃ , -CH = CH ₂ , -CH = CHCH ₃ (E form),-(CH ₂ ) ₂ CH = CH ₂ ,-( CH ₂ ) ₂ CH = CHCH ₃ (E form),-(CH ₂ ) ₄ CH = CH ₂ ,-(CH ₂ ) ₄ CH = CHCH ₃ (E form) or-(CH ₂ ) ₆ CH = CH ₂ Represent,
R ⁴ _{is, -CH 3, -CH 2 CH 3} , - (CH 2) 2 CH 3, - (CH 2) 3 CH 3, - (CH 2) 4 CH 3, - (CH 2) 5 CH 3, -(CH ₂ ) ₆ CH ₃ ,-(CH ₂ ) ₇ CH ₃ , -OCH ₃ , -OCH ₂ CH ₃ , -O (CH ₂ ) ₂ CH ₃ , -O (CH ₂ ) ₃ CH ₃ , -O (CH ₂ ) ₄ CH ₃ , -O (CH ₂ ) ₅ CH ₃ , -O (CH ₂ ) ₆ CH ₃ , -O (CH ₂ ) ₇ CH _3, -CH = CH ₂ , -CH = CHCH ₃ ( E-form),-(CH ₂ ) ₂ CH = CH ₂ ,-(CH ₂ ) ₂ CH = CHCH ₃ (E-form),-(CH ₂ ) ₄ CH = CH ₂ ,-(CH ₂ ) ₄ CH = CHCH More preferably, it represents ₃ (E form) or — (CH ₂ ) ₆ CH═CH ₂ .

B ¹ and B ² are each independently a trans-1,4-cyclohexylene group (one CH ₂ group present in this group or _two non-adjacent CH ₂ groups are substituted with oxygen atoms). 1,4-phenylene group (including one or more CH groups substituted by nitrogen atoms), 1,4-cyclohexenylene group 1,4-bicyclo [2.2.2] octylene group, piperidine-1,4-diyl group, naphthalene-2,6-diyl group, decahydronaphthalene-2,6-diyl group, or 1,2,3,4 -It preferably represents a tetrahydronaphthalene-2,6-diyl group or a substituent in which these hydrogen atoms are substituted with fluorine atoms, trans-1,4-cyclohexylene group, 1,4-phenylene group, fluorine-substituted A 1,4-phenylene group or a 1,4-bicyclo [2.2.2] octylene group is more preferable.

Y ¹ and Y ² are each independently -CH ₂ CH _2- , -CH = CH- (E form), -CH (CH ₃ ) CH _2- , -CH ₂ CH (CH ₃ )-, -CH (CH ₃ ) CH (CH ₃ )-, -CF ₂ CF _2- , -CF = CF- (E form), -CH ₂ O-, -OCH _2- , -OCH (CH ₃ )-, -CH ( CH ₃ ) O-,-(CH ₂ ) ₄ -,-(CH ₂ ) ₃ O-, -O (CH ₂ ) _3- , -C≡C-, -CF ₂ O-, -OCF ₂ -,- COO-, -OCO-, -COS-, -SCO- or a single bond is preferred, but -CH ₂ CH _2- , -CH = CH- (E form), -CH (CH ₃ ) CH _2- , -CH ₂ CH (CH ₃ )-, -CF ₂ CF _2- , -CF = CF- (E form), -CH ₂ O-, -OCH _2- , -OCH (CH ₃ )-, -CH ( CH ₃ ) O—, —C≡C—, —CF ₂ O—, —OCF ₂ — or a single bond is more preferable, and —CH ₂ CH ₂ —, —CH═CH— (E form) or a single bond is further preferable.
More specifically, the general formula (II) is preferably a compound represented by the group consisting of the following general formulas (II-A) to (II-I) as a specific structure.

(In the formula, R ¹³ , R ¹⁵ , R ¹⁷ , R ¹⁹ , R ²¹ , R ²⁷ and R ²⁹ are each independently -CH ₃ , -CH ₂ CH ₃ ,-(CH ₂ ) ₂ CH ₃ ,- (CH ₂ ) ₃ CH ₃ ,-(CH ₂ ) ₄ CH ₃ ,-(CH ₂ ) ₅ CH ₃ ,-(CH ₂ ) ₆ CH ₃ ,-(CH ₂ ) ₇ CH ₃ , -CH = CH ₂ , -CH = CHCH ₃ (E),-(CH ₂ ) ₂ CH = CH ₂ ,-(CH ₂ ) ₂ CH = CHCH ₃ (E),-(CH ₂ ) ₄ CH = CH ₂ ,-(CH _{2) 4 CH = CHCH 3 (} E form) or represents - (CH _{2) 6} CH = CH _2,
R ²³ and R ²⁵ are each independently -CH ₃ , -CH ₂ CH ₃ ,-(CH ₂ ) ₂ CH ₃ ,-(CH ₂ ) ₃ CH ₃ ,-(CH ₂ ) ₄ CH ₃ ,-( CH ₂ ) ₅ CH ₃ ,-(CH ₂ ) ₆ CH ₃ ,-(CH ₂ ) ₇ CH ₃ ,-(CH ₂ ) ₂ CH = CH ₂ ,-(CH ₂ ) ₂ CH = CHCH ₃ (E) ,-(CH ₂ ) ₄ CH = CH ₂ ,-(CH ₂ ) ₄ CH = CHCH ₃ (E form) or-(CH ₂ ) ₆ CH = CH ₂
R ¹⁴ , R ¹⁶ and R ¹⁸ are each independently -CH ₃ , -CH ₂ CH ₃ ,-(CH ₂ ) ₂ CH ₃ ,-(CH ₂ ) ₃ CH ₃ ,-(CH ₂ ) ₄ CH ₃ ,-(CH ₂ ) ₅ CH ₃ ,-(CH ₂ ) ₆ CH ₃ ,-(CH ₂ ) ₇ CH ₃ , -OCH ₃ , -OCH ₂ CH ₃ , -O (CH ₂ ) ₂ CH ₃ , -O (CH ₂ ) ₃ CH ₃ , -O (CH ₂ ) ₄ CH ₃ , -O (CH ₂ ) ₅ CH ₃ , -O (CH ₂ ) ₆ CH ₃ , -O (CH ₂ ) ₇ CH _3, -CH = CH ₂ , -CH = CHCH ₃ (E form),-(CH ₂ ) ₂ CH = CH ₂ ,-(CH ₂ ) ₂ CH = CHCH ₃ (E form),-(CH ₂ ) ₄ CH = CH ₂ ,-(CH ₂ ) ₄ CH = CHCH ₃ (E form) or-(CH ₂ ) ₆ CH = CH ₂
R ²⁰ , R ²² , R ²⁴ , R ²⁶ , R ²⁸ and R ³⁰ are each independently -CH ₃ , -CH ₂ CH ₃ ,-(CH ₂ ) ₂ CH ₃ ,-(CH ₂ ) ₃ CH ₃ ,-(CH ₂ ) ₄ CH ₃ ,-(CH ₂ ) ₅ CH ₃ ,-(CH ₂ ) ₆ CH ₃ ,-(CH ₂ ) ₇ CH ₃ , -OCH ₃ , -OCH ₂ CH ₃ , -O ( CH ₂ ) ₂ CH ₃ , -O (CH ₂ ) ₃ CH ₃ , -O (CH ₂ ) ₄ CH ₃ , -O (CH ₂ ) ₅ CH ₃ , -O (CH ₂ ) ₆ CH ₃ , -O ( CH ₂ ) ₇ CH _3, -(CH ₂ ) ₂ CH = CH ₂ ,-(CH ₂ ) ₂ CH = CHCH ₃ (E form),-(CH ₂ ) ₄ CH = CH ₂ ,-(CH ₂ ) ₄ CH═CHCH ₃ (E form) or — (CH ₂ ) ₆ CH═CH ₂ is represented. )
As an additional component, it is also preferable to contain one or more compounds selected from the compound group consisting of general formulas (III-A) to (III-J).

(Wherein R ³¹ and R ³² each independently represents an alkyl group having 1 to 10 carbon atoms or an alkenyl group having 2 to 10 carbon atoms, and one CH ₂ group present in these groups or adjacent thereto. Two or more CH ₂ groups not present may be substituted with O and / or S, and one or more hydrogen atoms present in these groups may be substituted with F or Cl. )
The nematic liquid crystal composition of the present invention contains 10 to 80% by mass of one or more compounds selected from the general formula (I), from the general formula (II-A) to the general formula (II-I). It is preferable to contain 20 to 70% by mass of one or more compounds selected from the group consisting of:
10 to 80% by mass of one or more compounds selected from the group consisting of general formula (IA) and general formula (IB), and from general formula (II-A) to general formula (II-I) More preferably, it contains 20 to 70% by mass of one or more compounds selected from the group consisting of:

  10 to 80% by mass of one or more compounds selected from the group consisting of compounds of general formula (IAI) to general formula (IA-VIII) and general formula (IBI) to general formula (IB-IV) More preferably, it contains 20 to 70% by mass of one or more compounds selected from the group consisting of general formula (II-A) to general formula (II-I).

In the present invention, the nematic phase-isotropic liquid phase transition temperature (Tni) is preferably 70 ° C., more preferably 75 ° C. or higher, and further preferably 80 ° C. or higher. In addition, since it is preferable that the nematic layer-isotropic liquid phase transition temperature (Tni) is as high as possible, it is not necessary to specifically limit the upper limit, but a practical upper limit is, for example, 130 ° C. Can do.
The dielectric anisotropy (Δε) at 25 ° C. is preferably −2.0 or less, more preferably −2.5 or less, and further preferably −3.0 or less. Since the absolute value of dielectric anisotropy (Δε) is preferably as large as possible, it is not necessary to specifically limit the lower limit value, but a practical lower limit value may be −8.0, for example. .

  The refractive index anisotropy (Δn) at 25 ° C. is more preferably 0.10 or more and even more preferably 0.12 or more when it corresponds to a thin cell gap. When it corresponds to a thick cell gap, it is more preferably 0.095 or less, and further preferably 0.085 or less. The refractive index anisotropy (Δn) is adjusted in accordance with each optimum value of the retardation expressed by the cell gap (d) and the product of both (Δn × d). Although it is not necessary to limit, as a practical range, 0.06 or more and 0.16 or less can be mentioned, for example.

  The viscosity is preferably 30 mPa · s or less, more preferably 25 mPa · s or less, and further preferably 20 mPa · s or less. Since the viscosity is preferably as low as possible, it is not necessary to specifically limit the lower limit value, but a practical lower limit value is, for example, 10 mPa · s.

The nematic liquid crystal composition is useful for a liquid crystal display element, particularly useful for an active matrix driving liquid crystal display element, and can be used for a VA mode, IPS mode or ECB mode liquid crystal display element.
The nematic liquid crystal composition of the present invention may contain a normal nematic liquid crystal, smectic liquid crystal, cholesteric liquid crystal and the like in addition to the above-mentioned compounds.

In the compound represented by the general formula (I-1) constituting the present invention,
R ^a represents a linear alkenyl group having 2 to 7 carbon atoms, but —CH═CH ₂ , —CH═CHCH ₃ (E form), — (CH ₂ ) ₂ CH═CH ₂ , — (CH ₂ ) ₂ CH = CHCH ₃ (E form),-(CH ₂ ) ₄ CH = CH ₂ or-(CH ₂ ) ₄ CH = CHCH ₃ (E form) are preferred,
R ^b represents a linear alkyl group having 1 to 7 carbon atoms or a linear alkenyl group having 2 to 7 carbon atoms, and examples of the linear alkyl group having 1 to 7 carbon atoms include ethyl, propyl Group, butyl group or pentyl group is preferred, and the alkenyl group having 2 to 7 carbon atoms is -CH = CH ₂ , -CH = CHCH ₃ (E form),-(CH ₂ ) ₂ CH = CH ₂ ,-( CH ₂ ) ₂ CH═CHCH ₃ (E-form), — (CH ₂ ) ₄ CH═CH ₂ or — (CH ₂ ) ₄ CH═CHCH ₃ (E-form) are preferred, and specifically represents the following structure: It is preferable.

(In the formula, R ^a represents —CH═CH ₂ , —CH═CHCH ₃ (E-form), — (CH ₂ ) ₂ CH═CH ₂ , — (CH ₂ ) ₂ CH═CHCH ₃ (E-form), -(CH ₂ ) ₄ CH = CH ₂ or-(CH ₂ ) ₄ CH = CHCH ₃ (E form), R ^b is a linear alkyl group having 1 to 5 carbon atoms or -CH = CH ₂ , -CH = CHCH ₃ (E form),-(CH ₂ ) ₂ CH = CH ₂ ,-(CH ₂ ) ₂ CH = CHCH ₃ (E form),-(CH ₂ ) ₄ CH = CH ₂ or-(CH ₂ ) ₄ CH = CHCH ₃ (E form))
The compound of the present invention can be produced as follows.

(Production method 1)
Formula (9)

で表されるジケトン化合物に対し、メトキシメチルトリフェニルホスホニウムクロリドより調製されるイリドを反応させて式(10)

Is reacted with an ylide prepared from methoxymethyltriphenylphosphonium chloride to form a diketone compound represented by formula (10):

で表される化合物を得る。得られた式(10)の化合物を酸触媒加水分解し、更に塩基性条件下でシス−トランス異性化することにより式(11)

To obtain a compound represented by: The resulting compound of formula (10) is subjected to acid-catalyzed hydrolysis and further cis-trans isomerization under basic conditions to give a compound of formula (11)

で表される化合物を得る。得られた式(11)の化合物に対し、メチルトリフェニルホスホニウムブロミドより調製されるイリドを反応させて式(12)

To obtain a compound represented by: The resulting compound of formula (11) is reacted with an ylide prepared from methyltriphenylphosphonium bromide to give a compound of formula (12)

で表される化合物を得る。得られた式(12)の化合物を水素化ほう素ナトリウム等の還元剤を用いて還元して式(13)

To obtain a compound represented by: The resulting compound of formula (12) is reduced using a reducing agent such as sodium borohydride to obtain the formula (13)

で表される化合物を得る。得られた式(13)の化合物を一般式(14)

To obtain a compound represented by: The obtained compound of the formula (13) is represented by the general formula (14)

（式中、X¹は塩素、臭素、よう素、ベンゼンスルホニルオキシ基、p-トルエンスルホニルオキシ基、メタンスルホニルオキシ基又はトリフルオロメタンスルホニルオキシ基を表す。）で表される化合物へ変換し、2,3-ジフルオロフェノールから調製されるフェノラートと反応させることにより式(15)

(Wherein X ¹ represents chlorine, bromine, iodine, benzenesulfonyloxy group, p-toluenesulfonyloxy group, methanesulfonyloxy group or trifluoromethanesulfonyloxy group), (15) by reacting with phenolate prepared from 1,3-difluorophenol

で表される化合物を得る。これを酸化することにより式(16)

To obtain a compound represented by: By oxidizing this, the formula (16)

で表される化合物を得る。これより調製されるフェノラートと一般式(17)

To obtain a compound represented by: Phenolates prepared from this and general formula (17)

（式中、R^aは一般式(I-1)と同じ意味を表し、X²は一般式(14)におけるX¹と同じ意味を表す。）で表される化合物を反応させることにより一般式(18)

(Wherein R ^a represents the same meaning as in general formula (I-1), and X ² represents the same meaning as X ¹ in general formula (14)). (18)

（式中、R^aは一般式(I-1)と同じ意味を表す。）で表される化合物を得ることができる。

(Wherein, ^Ra represents the same meaning as in general formula (I-1)) can be obtained.

(Production method 2)
Formula (19)

で表される化合物に対し、式(9)から式(11)への変換と同様の反応を行うことにより式(20)

The compound represented by formula (20) is subjected to a reaction similar to the conversion from formula (9) to formula (11).

で表される化合物を得る。得られた式(20)の化合物を水素化ほう素ナトリウム等の還元剤を用いて還元して式(21)

To obtain a compound represented by: The resulting compound of formula (20) is reduced using a reducing agent such as sodium borohydride to obtain a compound of formula (21)

で表される化合物を得る。得られた式(21)で表される化合物を一般式(22)

To obtain a compound represented by: The resulting compound represented by the formula (21) is represented by the general formula (22)

（式中、X²は一般式(14)におけるX¹と同じ意味を表す。）で表される化合物へと変換し、酸性条件下で脱保護することにより一般式(23)

(In the formula, X ² represents the same meaning as X ¹ in the general formula (14)), and is converted to a compound represented by the general formula (23) by deprotection under acidic conditions.

（式中、X²は一般式(14)におけるX¹と同じ意味を表す。）で表される化合物を得る。得られた一般式(23)で表される化合物に対し、式(9)から式(11)への変換と同様の反応を行うことにより式(24)

(Wherein X ² represents the same meaning as X ¹ in formula (14)). The compound represented by the general formula (23) thus obtained is subjected to a reaction similar to the conversion from the formula (9) to the formula (11) to obtain the formula (24).

（式中、X²は一般式(14)におけるX¹と同じ意味を表す。）で表される化合物を得る。得られた一般式(24)で表される化合物とメチルトリフェニルホスフィンブロミドより調製されるイリドを反応させることにより一般式(25)

(Wherein X ² represents the same meaning as X ¹ in formula (14)). By reacting the compound represented by the general formula (24) thus obtained with an ylide prepared from methyltriphenylphosphine bromide, the general formula (25)

（式中、X²は一般式(14)におけるX¹と同じ意味を表す。）で表される化合物を得る。得られた一般式(25)で表される化合物を一般式(26)

(Wherein X ² represents the same meaning as X ¹ in formula (14)). The compound represented by the general formula (25) thus obtained is represented by the general formula (26).

（式中、R^aは一般式(I-1)と同じ意味を表す。）
で表されるフェノール化合物から調製されるフェノラートと反応させることにより一般式(18)で表される化合物を得ることができる。
(製法4)
式(27)

(Wherein, R ^a represents the same meaning as the general formula (I-1).)
A compound represented by the general formula (18) can be obtained by reacting with a phenolate prepared from a phenol compound represented by the formula:
(Manufacturing method 4)
Formula (27)

で表される化合物に対し、式(9)から式(12)への変換と同様の反応を行うことにより式(28)

The compound represented by formula (28) is subjected to a reaction similar to the conversion from formula (9) to formula (12).

で表される化合物を得る。得られた式(28)で表される化合物を水素化リチウムアルミニウム、水素化ビス(2-メトキシエトキシ)アルミニウムナトリウム等の還元剤により還元して式(29)

To obtain a compound represented by: The resulting compound represented by the formula (28) is reduced with a reducing agent such as lithium aluminum hydride, sodium bis (2-methoxyethoxy) aluminum hydride, and the formula (29)

で表される化合物を得る。得られた式(29)で表される化合物を一般式(30)

To obtain a compound represented by: The resulting compound represented by the formula (29) is represented by the general formula (30)

（式中、X³は一般式(14)におけるX¹と同じ意味を表す。）で表される化合物へと変換し、
一般式(26)で表されるフェノール化合物から調製されるフェノラートと反応させることにより一般式(31)

(Wherein X ³ represents the same meaning as X ¹ in the general formula (14)),
By reacting with a phenolate prepared from a phenol compound represented by the general formula (26), the general formula (31)

（式中、R^aは一般式(I-1)と同じ意味を表す。）で表される化合物を得ることができる。
(製法3)
式(39)

(Wherein, ^Ra represents the same meaning as in general formula (I-1)) can be obtained.
(Manufacturing method 3)
Formula (39)

で表される化合物に対し、酸性・脱水条件下、エチレングリコールと反応させて式(40)

The compound represented by formula (40) is reacted with ethylene glycol under acidic and dehydrating conditions.

で表される化合物を得る。得られた式(40)で表される化合物を水素化リチウムアルミニウム、水素化ビス(2-メトキシエトキシ)アルミニウムナトリウム等の還元剤により還元して式(41)

To obtain a compound represented by: The resulting compound represented by the formula (40) is reduced with a reducing agent such as lithium aluminum hydride, sodium bis (2-methoxyethoxy) aluminum hydride, and the formula (41).

で表される化合物を得る。得られた式(41)で表される化合物を一般式(42)

To obtain a compound represented by: The resulting compound represented by the formula (41) is represented by the general formula (42)

（式中、X¹は塩素、臭素、よう素、ベンゼンスルホニルオキシ基、p-トルエンスルホニルオキシ基、メタンスルホニルオキシ基又はトリフルオロメタンスルホニルオキシ基を表す。）で表される化合物へ変換し、2,3-ジフルオロフェノールから調製されるフェノラートと反応させることにより式(43)

(Wherein X ¹ represents chlorine, bromine, iodine, benzenesulfonyloxy group, p-toluenesulfonyloxy group, methanesulfonyloxy group or trifluoromethanesulfonyloxy group), By reacting with phenolate prepared from 1,3-difluorophenol

で表される化合物を得る。得られた式(43)で表される化合物を、酸性条件下で脱保護することにより式(44)

To obtain a compound represented by: The obtained compound represented by the formula (43) is deprotected under acidic conditions to obtain the formula (44).

で表される化合物を得る。得られた式(44)で表される化合物に対し、メトキシメチルトリフェニルホスホニウムクロリドより調製されるイリドを反応させて式(45)

To obtain a compound represented by: The resulting compound represented by the formula (44) is reacted with an ylide prepared from methoxymethyltriphenylphosphonium chloride to obtain a compound represented by the formula (45).

で表される化合物を得る。得られた式(45)の化合物を酸性条件下で加水分解し、更に塩基性条件下でシス−トランス異性化することにより式(46)

To obtain a compound represented by: The resulting compound of formula (45) is hydrolyzed under acidic conditions, and further cis-trans isomerized under basic conditions to give formula (46)

で表される化合物を得る。得られた式(46)の化合物に対し、式(44)から式(46)への変換反応（ただしシス−トランス異性化は行わない）を2回行うことにより式(47)

To obtain a compound represented by: The resulting compound of formula (46) is subjected to a conversion reaction from formula (44) to formula (46) (but without cis-trans isomerization) twice to give formula (47)

で表される化合物を得る。得られた式(47)で表される化合物に対し、メチルトリフェニルホスホニウムブロミドより調製されるイリドを反応させて式(48)

To obtain a compound represented by: The resulting compound represented by formula (47) is reacted with ylide prepared from methyltriphenylphosphonium bromide to formula (48)

で表される化合物を得る。得られた式(48)で表される化合物を酸化して、式(49)

To obtain a compound represented by: The obtained compound represented by the formula (48) is oxidized to obtain the formula (49).

で表される化合物を得る。得られた式(49)で表される化合物から調製されるフェノラートと一般式(50)

To obtain a compound represented by: Phenolate prepared from the compound represented by formula (49) and general formula (50)

（式中、X¹は一般式(42)におけるものと同じ意味を表し、p2及びR^bはそれぞれ一般式(I-1)におけるものと同じ意味を表す。）で表される化合物を反応させることにより一般式(51)

(Wherein X ¹ represents the same meaning as in general formula (42), and p2 and R ^b represent the same meaning as in general formula (I-1), respectively). General formula (51)

（式中、p2及びR^bはそれぞれ一般式(I-1)におけるものと同じ意味を表す。）で表される化合物を得ることができる。

(Wherein, p2 and ^Rb have the same meaning as in general formula (I-1), respectively).

(Manufacturing method 5)
The compound represented by the formula (46) is reacted with an ylide prepared from ethyltriphenylphosphonium bromide and subjected to E / Z isomerization under acidic conditions to form the formula (52).

で表される化合物を得る。得られた式(52)で表される化合物に対し、式(48)から一般式(51)への変換反応を行うことにより一般式(53)

To obtain a compound represented by: The resulting compound represented by formula (52) is subjected to a conversion reaction from formula (48) to formula (51) to give a formula (53)

（式中、p2及びR^bはそれぞれ一般式(I-1)におけるものと同じ意味を表す。）で表される化合物を得ることができる。

(Wherein, p2 and ^Rb have the same meaning as in general formula (I-1), respectively).

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples. The structure of the compound was confirmed by nuclear magnetic resonance spectrum (NMR), mass spectrum (MS) and the like. Further, “%” in the compositions of the following Examples and Comparative Examples means “% by mass”.
The following abbreviations are used in compound descriptions.
THF: tetrahydrofuran
DMF: N, N-dimethylformamide
Me: methyl group
Et: ethyl group
Bu: Butyl group
Pen: pentyl group
Pr: Propyl group
Ms: Methanesulfonyl group In the examples, the measured physical property values are as follows.
T _NI : Nematic-isotropic phase transition temperature (° C)
Δn: Birefringence at 25 ° C. Δε: Dielectric anisotropy at 25 ° C. η: Viscosity (mPa · s) (20 ° C.)
C, N, and I represent a crystal phase, a nematic phase, and an isotropic phase, respectively.

Example 1 Synthesis of 2,3-difluoro-1- (trans-4-ethylcyclohexyl) methoxy-4- (trans-4- (trans-4-vinylcyclohexyl) cyclohexyl) methoxybenzene (1a)

(1-1) Synthesis of 4,4′-bismethoxymethylidenebicyclohexyl 882.3 g of methoxymethyltriphenylphosphonium chloride was dispersed in 2600 mL of THF and cooled to −10 ° C. While maintaining the internal temperature, 313.2 g of potassium-t-butoxide was added. After stirring for 1 hour while maintaining the internal temperature, a solution of bicyclohexyl-4,4′-dione 200.0 g in THF (800 mL) was added dropwise. After stirring for 1 hour while maintaining the internal temperature, water was added to stop the reaction. After the solvent was distilled off under reduced pressure, hexane was added and stirred vigorously, followed by filtration (twice). The filtrates were combined, washed with a 50% aqueous methanol solution and saturated brine in that order, and dried over anhydrous magnesium sulfate. The solvent was distilled off to obtain 231.8 g of a white solid.

(1-2) Synthesis of trans, trans-bicyclohexyl-4,4'-dicarbaldehyde
To a solution of 231.8 g of the solid obtained in (1-1) in THF (930 mL) was added 700 mL of 10% hydrochloric acid, and the mixture was heated to reflux for 1 hour. After allowing the reaction solution to cool, the organic layer was separated and extracted from the aqueous layer with toluene (4 times). The combined organic layers were washed with saturated brine, and then dried over anhydrous magnesium sulfate. The solvent was distilled off under reduced pressure to obtain 204.5 g of a reddish brown liquid. This was dissolved in 800 mL of methanol, and 80 mL of 10% aqueous sodium hydroxide solution was added dropwise while maintaining the internal temperature while stirring vigorously at −10 ° C. The mixture was stirred for 2 hours while maintaining the internal temperature. Water was added, and the precipitated solid was collected by suction filtration. The obtained solid was washed with water and methanol in this order and dried to obtain 189.4 g of a white solid.

(1-3) Synthesis of 4'-vinylbicyclohexyl-4-carbaldehyde Methyltriphenylphosphonium bromide (192.5 g) was dispersed in THF (580 mL) and vigorously stirred at -10 ° C while maintaining the internal temperature. Potassium-t-butoxide 66.6 g was added. The mixture was stirred for 1 hour while maintaining the internal temperature, and added dropwise to a solution of 120.0 g of the solid obtained in (1-2) in THF (1800 mL) at an internal temperature of 5 ° C. After stirring for 1 hour while maintaining the internal temperature, water was added to stop the reaction. The reaction solution was washed with 5% aqueous ammonium chloride solution. The solvent of the organic layer was distilled off, hexane and toluene were added, and the mixture was washed with 50% aqueous methanol. After drying over anhydrous magnesium sulfate, the solvent was distilled off under reduced pressure to obtain 60.1 g of an almost colorless solid.

(1-4) Synthesis of trans-4- (trans-4-vinylcyclohexyl) cyclohexylmethanol While maintaining a solution of 1.65 g of sodium borohydride in ethanol (120 mL) at -10 ° C, the internal temperature was maintained. Then, a solution of 60.1 g of the almost colorless solid obtained in (1-3) in THF (180 mL) was added dropwise. After warming to room temperature, the mixture was stirred for 2 hours, and water, ethyl acetate, and an aqueous ammonium chloride solution were added to stop the reaction. Saturated brine was added to the reaction solution, the organic layer was separated, and the aqueous layer was extracted with ethyl acetate (twice). The combined organic layers were washed with saturated brine and dried over anhydrous magnesium sulfate. The solvent was distilled off under reduced pressure and purified by column chromatography to obtain 15.4 g of trans-4- (trans-4-vinylcyclohexyl) cyclohexylmethanol as a white solid.

(1-5) Methanesulfonic acid Synthesis of trans-4- (trans-4-vinylcyclohexyl) cyclohexylmethyl Trans-4- (trans-4-vinylcyclohexyl) cyclohexylmethanol 15.1 g, pyridine 8.2 mL and 4-dimethylaminopyridine 0.41 g was dissolved in 50 mL of dichloromethane. Under ice-cooling, a solution of 6.3 mL of methanesulfonyl chloride in 6 mL of dichloromethane was added dropwise over 30 minutes, the temperature was raised to room temperature, stirred for 6 hours, and left overnight. The reaction solution was poured into 10% hydrochloric acid, the organic layer was separated, and the aqueous layer was extracted with dichloromethane. The organic layers were combined, washed with saturated brine, and dried over anhydrous magnesium sulfate. The solvent was distilled off under reduced pressure, and the residue was purified by column chromatography (silica gel / toluene) and recrystallization (hexane / toluene) three times, and methanesulfonic acid trans-4- (trans-4-vinylcyclohexyl) cyclohexyl as colorless crystals. Methyl 9.8 g was obtained.

(1-6) Synthesis of 2,3-difluoro-1- (trans-4- (trans-4-vinylcyclohexyl) cyclohexyl) methoxybenzene Methanesulfonic acid trans-4- (trans-4-vinylcyclohexyl) cyclohexylmethyl After dissolving in DMF, 2,3-difluorophenol and tripotassium phosphate were added and stirred at 80 ° C. for 2 hours. Water and toluene were added, the organic layer was separated, washed with water and saturated brine, and dried over anhydrous sodium sulfate. The solvent was distilled off under reduced pressure, and the residue was purified by column chromatography to obtain 2,3-difluoro-1- (trans-4- (trans-4-vinylcyclohexyl) cyclohexyl) methoxybenzene.

(1-7) Synthesis of 2,3-difluoro-4- (trans-4- (trans-4-vinylcyclohexyl) cyclohexyl) methoxyphenol
2,3-Difluoro-1- (trans-4- (trans-4-vinylcyclohexyl) cyclohexyl) methoxybenzene 15.7 g was dissolved in THF 80 mL, and sec-butyllithium (1.01 M hexane, cyclohexane solution) 51 mL was added dropwise at an internal temperature of −45 ° C. or lower, and the mixture was further stirred for 30 minutes. Thereto, 5.9 g of trimethyl borate was added dropwise at an internal temperature of −40 ° C. or lower, and the mixture was further stirred for 30 minutes, and the temperature was raised to 0 ° C. Thereafter, 16 mL of water was added, and 16 mL of 15% aqueous hydrogen peroxide was added dropwise over 30 minutes, followed by stirring for 3 hours. Water and toluene were added, the organic layer was separated, and the aqueous layer was extracted with toluene. The organic layers were combined, washed with saturated brine, and dried over anhydrous magnesium sulfate. The solvent was distilled off under reduced pressure, and the residue was purified by column chromatography and recrystallization to obtain 2,3-difluoro-4- (trans-4- (trans-4-vinylcyclohexyl) cyclohexyl) methoxyphenol.

(1-8) Synthesis of 2,3-difluoro-1- (trans-4-ethylcyclohexyl) methoxy-4- (trans-4- (trans-4-vinylcyclohexyl) cyclohexyl) methoxybenzene (1a)
6.5 g of 2,3-difluoro-4- (trans-4- (trans-4-vinylcyclohexyl) cyclohexyl) methoxyphenol was dissolved in 35 mL of DMF, and 4.9 g of (trans-4-ethylcyclohexyl) methyl bromide and 6.4 g of tripotassium phosphate was added and stirred at 80 ° C. for 2 hours. Water and toluene were added, the organic layer was separated, washed with saturated brine, and dried over anhydrous sodium sulfate. The solvent was distilled off under reduced pressure, and the residue was purified by recrystallization and column chromatography to give 2,3-difluoro-1- (trans-4-ethylcyclohexyl) methoxy-4- (trans-4- (trans- 3.8 g of 4-vinylcyclohexyl) cyclohexyl) methoxybenzene (1 a) was obtained.

Phase transition temperature C 94.1 N 197.5 I
MS m / z: 474 (M ⁺ ), 146 (100)
¹ H-NMR (400 MHz, CDCl ₃ )
δ: 0.88 (t, J = 7.2 Hz, 3 H), 0.90 1.30 (m, 17 H), 1.65 2.00 (m, 15 H), 3.70 3.80 (m, 4 H), 4.80 5.00 (m, 2 H) , 5.77 (ddd, J = 16.8 Hz, J = 10.4 Hz, J = 6.4 Hz, 1 H), 6.59 (d, J = 5.6 Hz, 2 H)
Example 2 Synthesis of 2,3-difluoro-1- (trans-4-ethylcyclohexyl) methoxy-4- (trans-4-vinylcyclohexyl) methoxybenzene (1b)

(2-1) Synthesis of 2,3-difluoro-1- (trans-4-ethylcyclohexyl) methoxybenzene
30 g of 2,3-difluorophenol was dissolved in 300 mL of DMF, 56.8 g of (trans-4-ethylcyclohexyl) methyl bromide and 73.4 g of tripotassium phosphate were added, and the mixture was stirred at 100 110 ° C. for 1 hour. Water and toluene were added, the organic layer was separated, and the aqueous layer was extracted with toluene. The organic layers were combined and washed with saturated brine, followed by column chromatography, and the solvent was distilled off under reduced pressure. The residue was purified by recrystallization to obtain 37 g of 2,3-difluoro-1- (trans-4-ethylcyclohexyl) methoxybenzene.

(2-2) Synthesis of 2,3-difluoro-4- (trans-4-ethylcyclohexyl) methoxyphenol
37 g of 2,3-difluoro-1- (trans-4-ethylcyclohexyl) methoxybenzene was dissolved in 222 mL of THF, and 59.9 mL of butyllithium (2.67 M hexane solution) was added dropwise thereto at an internal temperature of -40 ° C or lower. The mixture was further stirred for 30 minutes. To this, 18.1 g of trimethyl borate was added dropwise at an internal temperature of -40 ° C or lower, and the temperature was raised to 0 ° C. Thereafter, 24.7 mL of 30% hydrogen peroxide solution was added dropwise over 5 minutes, followed by stirring for 3 hours. Water and toluene were added, the organic layer was separated, and the aqueous layer was extracted with toluene. The organic layers were combined and washed with water, and the solvent was distilled off under reduced pressure. The obtained residue was purified by column chromatography to obtain 20 g of 2,3-difluoro-4- (trans-4-ethylcyclohexyl) methoxyphenol.

(2-3) Synthesis of methyl 4-methoxymethylidenecyclohexanecarboxylate 263.4 g of methoxymethyltriphenylphosphonium chloride was dispersed in 750 mL of tetrahydrofuran, and 86.2 g of potassium-t-butoxide was added thereto at −9 to −4 ° C. Added over 5 minutes. Further, after stirring at −4 to −11 ° C. for 30 minutes, 100.0 g of methyl 4-oxocyclohexanecarboxylate was dissolved in 300 mL of THF and added dropwise at −10 to 4 ° C. over 80 minutes. After further stirring for 60 minutes at 0 to 4 ° C., 7.0 g of ammonium chloride and 20 mL of water were added. After the solvent of the reaction mixture was distilled off under reduced pressure, 600 mL of hexane was added and stirred at room temperature for 30 minutes. After the precipitate was filtered off, the precipitate was suspended and washed again with 600 mL of hexane, and the hexane filtrate was combined and washed with a methanol-water (1: 1) mixture, water, and saturated brine in this order. After drying over anhydrous sodium sulfate, the solvent was distilled off under reduced pressure to obtain 103 g of methyl 4-methoxymethylidenecyclohexanecarboxylate as an oil.

(2-4) Synthesis of methyl 4-formylcyclohexanecarboxylate
103 g of methyl 4-methoxymethylidenecyclohexanecarboxylate was dissolved in 350 mL of THF, and 100 mL of 10% hydrochloric acid was added dropwise thereto at 11-13 ° C. over 10 minutes. After further stirring for 3 hours at room temperature, 80 mL of hexane was added. The aqueous layer was extracted with ethyl acetate, and the organic layers were combined and washed sequentially with water and saturated brine. After drying over anhydrous magnesium sulfate and concentrating, 92.4 g of methyl 4-formylcyclohexanecarboxylate was obtained as an oil. As a result of analysis by gas chromatography, the obtained product was a 64:36 mixture of cis and trans isomers.

(2-5) Synthesis of methyl 4-vinylcyclohexanecarboxylate 297.4 g of methyltriphenylphosphonium bromide was dispersed in 900 mL of THF, and 95.6 g of potassium-t-butoxide was added thereto at -8 ° C over 3 minutes. After further stirring for 30 minutes, 92.4 g of methyl 4-formylcyclohexanecarboxylate was dissolved in 270 mL of THF and added dropwise at −6 to 4 ° C. over 50 minutes. After further stirring at 0-4 ° C. for 30 minutes, 15 mL of water was added. The solvent of the reaction mixture was distilled off under reduced pressure, 500 mL of hexane was added, and the mixture was stirred at room temperature for 30 minutes. After the precipitate was filtered off, the precipitate was suspended and washed again with 500 mL of hexane, and the hexane filtrate was combined and washed with a methanol-water (1: 1) mixture, water, and saturated brine in this order. After drying over anhydrous sodium sulfate, the solvent was distilled off under reduced pressure to obtain 81.2 g of an oil. Distillation under reduced pressure gave 57.3 g of methyl 4-vinylcyclohexanecarboxylate. Boiling point 122-127 ° C / 48hPa. As a result of gas chromatography analysis, the obtained product was a 26:74 mixture of cis- and trans-isomers.

(2-6) Synthesis of trans-4-vinylcyclohexanecarboxylic acid
After dissolving 55.3 g of methyl 4-vinylcyclohexanecarboxylate in 60 mL of methanol and cooling to 15 ° C., 100 g of a 20% aqueous sodium hydroxide solution was added thereto. After further stirring at room temperature for 2 hours, concentrated hydrochloric acid was added to acidify the system. After extraction with hexane, the organic layer was washed with saturated brine. The extract was dried over anhydrous sodium sulfate and concentrated to obtain 52.4 g of a reaction mixture. Recrystallization from hexane gave 23.0 g of trans-4-vinylcyclohexanecarboxylic acid.

(2-7) Synthesis of methyl trans-4-vinylcyclohexanecarboxylate Dissolve 23.0 g of trans-4-vinylcyclohexanecarboxylic acid in 120 mL of methanol, add 0.1 g of trimethylsilyl chloride, reflux for 6 hours, and cool to room temperature. Concentrated under reduced pressure. After adding 150 mL of hexane and separating the methanol layer, the methanol layer was extracted with hexane, and the organic layers were combined and washed with saturated brine. The extract was dried over anhydrous sodium sulfate and concentrated to obtain 29.5 g of methyl trans-4-vinylcyclohexanecarboxylate as an oily substance.

(2-8) Synthesis of (trans-4-vinylcyclohexyl) methanol 5.7 g of lithium aluminum hydride was dispersed in 50 mL of THF, and 29.5 g of methyl trans-4-vinylcyclohexanecarboxylate was dissolved in 75 mL of THF, and 15-16 The solution was added dropwise at 40 ° C. over 40 minutes. Furthermore, after stirring at 10-20 degreeC for 30 minutes, water was added slowly. About 70 mL of 10% hydrochloric acid was added, and sludge-like insoluble matter was removed with a decanter while rinsing with hexane, and the obtained organic layer was washed with 10% hydrochloric acid, saturated aqueous sodium hydrogen carbonate, and saturated brine in this order. The extract was dried over anhydrous sodium sulfate and concentrated to obtain 26 g of (trans-4-vinylcyclohexyl) methanol.

(2-9) Synthesis of methyl methanesulfonate (trans-4-vinylcyclohexyl)
26 g of (trans-4-vinylcyclohexyl) methanol was dissolved in 100 mL of dichloromethane, and 23.6 g of pyridine and 0.9 g of 4-dimethylaminopyridine were added. To this, 18.8 g of methanesulfonyl chloride was dissolved in 36 mL of dichloromethane and added dropwise at 14 to 20 ° C. over 25 minutes. The mixture was further stirred at room temperature for 7 hours and allowed to stand overnight. After adding 40 mL of water and separating the organic layer, the organic layer was washed sequentially with 10% hydrochloric acid, water, saturated aqueous sodium hydrogen carbonate, and saturated aqueous ammonium chloride. The extract was dried over anhydrous magnesium sulfate and concentrated to obtain 32.7 g of a solid. Recrystallization from hexane gave 30.8 g of methyl methanesulfonate (trans-4-vinylcyclohexyl).

(2-10) Synthesis of 2,3-difluoro-1- (trans-4-ethylcyclohexyl) methoxy-4- (trans-4-vinylcyclohexyl) methoxybenzene (1b)
To a solution of 2,3-difluoro-4- (trans-4-ethylcyclohexyl) methoxyphenol 10 g in DMF (50 ml), tripotassium phosphate 12 g and methanesulfonic acid (trans-4-vinylcyclohexyl) methyl 8.1 g And stirred at 80 100 ° C. for 2 hours. Water and toluene were added, the organic layer was separated, washed with water and saturated brine, and dried over silica gel. The solvent was distilled off under reduced pressure, the residue was purified by recrystallization and column chromatography, and 2,3-difluoro-1- (trans-4-ethylcyclohexyl) methoxy-4- (trans-4-vinylcyclohexyl) was obtained as colorless crystals. 7.9 g of methoxybenzene (1b) was obtained.
Phase transition temperature C 59.2 N 77.1 I
MS m / z: 392 (M ⁺ ), 146 (100)
¹ H-NMR (400 MHz, CDCl ₃ )
δ: 0.88 (t, J = 7.6 Hz, 3 H), 0.90 1.30 (m, 11 H), 1.65 2.00 (m, 11 H), 3.70 3.80 (m, 4 H), 4.85 5.05 (m, 2 H) , 5.79 (ddd, J = 17.2 Hz, J = 10.4 Hz, J = 6.8 Hz, 1 H), 6.60 (d, J = 5.6 Hz, 2 H)
Example 3 Synthesis of 2,3-difluoro-1-((trans-4-ethylcyclohexyl) methoxy) -4-((trans-4- (3-butenyl) cyclohexyl) methoxy) benzene (1c)

(3-1) Synthesis of methyl 4- (4 ', 4'-ethylenedioxy) cyclohexanecarboxylate
300 mL of methyl 4-oxocyclohexanecarboxylate was dissolved in 900 mL of toluene, 257 mL of ethylene glycol and 5 g of p-toluenesulfonic acid hydrate were added, and the mixture was heated to reflux for 4 hours while removing generated water. After cooling to room temperature, 100 mL of saturated aqueous sodium hydrogen carbonate solution was added dropwise, 500 mL of water was added, and the organic layer was separated. The aqueous layer was extracted with toluene, and the organic layers were combined, washed with water and saturated brine, and dried over anhydrous sodium sulfate. The solvent was distilled off under reduced pressure until the total amount was about 1.2 L to obtain a toluene solution of methyl 4- (4 ′, 4′-ethylenedioxy) cyclohexanecarboxylate.

(3-2) Synthesis of (4- (4 ', 4'-ethylenedioxy) cyclohexyl) methanol
To the toluene solution obtained in (1-1), 832 g of 70% bis (2-methoxyethoxy) aluminum sodium toluene solution was added dropwise, and the mixture was further stirred for 2 hours. To the reaction solution, 100 mL of ethyl acetate was added dropwise, 500 mL of water was added, and the organic layer was separated. The aqueous layer was extracted with toluene, and the organic layers were combined, washed with water and saturated brine, and dried over anhydrous sodium sulfate. The solvent was distilled off under reduced pressure, and the residue was distilled under reduced pressure (179 184 ° C./2.5 kPa) to obtain 153.9 g of (4- (4 ′, 4′-ethylenedioxy) cyclohexyl) methanol as a colorless oily substance.

(3-3) Synthesis of (4- (4 ', 4'-ethylenedioxy) cyclohexyl) methyl methanesulfonate
153.9 g of (4- (4 ′, 4′-ethylenedioxy) cyclohexyl) methanol was dissolved in 500 mL of dichloromethane, and 108 mL of pyridine and 11 g of 4-dimethylaminopyridine were added and cooled with ice. Methanesulfonyl chloride (83 mL) was added dropwise over 30 minutes, and the mixture was warmed to room temperature and stirred for 2 hours. The reaction solution was poured into 400 mL of water, the organic layer was separated, and the aqueous layer was extracted with dichloromethane. The organic layers were combined, washed with water, saturated aqueous sodium hydrogen carbonate solution and saturated brine, and dried over anhydrous sodium sulfate. The solvent was distilled off under reduced pressure, and the residue was purified by column chromatography to obtain 230.6 g of methanesulfonic acid (4- (4 ′, 4′-ethylenedioxy) cyclohexyl) methyl as a pale yellow oily substance.

(3-4) Synthesis of 1-((4- (4 ', 4'-ethylenedioxy) cyclohexyl) methoxy) -2,3-difluorobenzene Methanesulfonic acid (4- (4', 4'-ethylenedi 15.9 g of oxy) cyclohexyl) methyl was dissolved in 150 mL of DMF, 20.2 g of tripotassium phosphate and 9.1 g of 2,3-difluorophenol were added, and the mixture was stirred at 80 ° C. for 2 hours. The reaction solution was poured into water and extracted with toluene, and the organic layer was washed with water and saturated brine, and dried over silica gel. The solvent was distilled off under reduced pressure until the total amount reached about 100 mL to obtain a toluene solution of 1- (4- (4 ′, 4′-ethylenedioxy) cyclohexyl) methoxy-2,3-difluorobenzene.

(3-5) Synthesis of 1-((4-oxocyclohexyl) methoxy) -2,3-difluorobenzene
80 mL of formic acid was added to the toluene solution obtained in (1-4), and the mixture was stirred at room temperature for 6 hours. Water and toluene were added, and the organic layer was separated, washed with water and saturated brine, and dried over anhydrous sodium sulfate. The solvent was distilled off under reduced pressure to obtain 13.8 g of 1-((4-oxocyclohexyl) methoxy) -2,3-difluorobenzene.

(3-6) Synthesis of 1-((trans-4-formylcyclohexyl) methoxy) -2,3-difluorobenzene
13.8 g of 1-((4-oxocyclohexyl) methoxy) -2,3-difluorobenzene was dissolved in 50 mL of THF, and 23.6 g of methoxymethyltriphenylphosphonium chloride was added. Thereto, a THF (20 mL) solution of 7.7 g of potassium-t-butoxide was added dropwise at an internal temperature of 10 25 ° C., and the mixture was stirred for 30 minutes. 10 mL of water was added and the solvent was distilled off under reduced pressure. Hexane and 50% aqueous methanol solution were added to separate the organic layer. This was washed with 50% aqueous methanol solution and saturated brine, and subjected to column chromatography. The solvent was distilled off under reduced pressure, the residue was dissolved in 100 mL of THF, 100 mL of 10% hydrochloric acid was added, and the mixture was heated to reflux for 3 hours. Water and ethyl acetate were added, and the organic layer was separated, washed successively with saturated brine, saturated aqueous sodium hydrogen carbonate solution and saturated brine, dried over anhydrous sodium sulfate, and the solvent was evaporated under reduced pressure. Methanol 30 mL and 20% aqueous sodium hydroxide solution were added to the residue, and the mixture was stirred for 2 hours under ice cooling. Water and ethyl acetate were added, and the organic layer was separated, washed 3 times with saturated brine, and dried over anhydrous sodium sulfate. The solvent was distilled off under reduced pressure to obtain 11.5 g of 1-((trans-4-formylcyclohexyl) methoxy) -2,3-difluorobenzene.

(3-7) Synthesis of 1-((trans-4- (formylmethyl) cyclohexyl) methoxy) -2,3-difluorobenzene
11.5 g of 1-((trans-4-formylcyclohexyl) methoxy) -2,3-difluorobenzene was dissolved in 50 mL of THF, and 18.6 g of methoxymethyltriphenylphosphonium chloride was added. Thereto was added dropwise a solution of 6.1 g of potassium-t-butoxide in THF (20 mL) at an internal temperature of 520 ° C. and stirred for 30 minutes. 10 mL of water was added and the solvent was distilled off under reduced pressure. Hexane and 50% aqueous methanol solution were added to separate the organic layer. This was washed with 50% aqueous methanol solution and saturated brine, and subjected to column chromatography. The solvent was distilled off under reduced pressure, the residue was dissolved in 70 mL of THF, 70 mL of 10% hydrochloric acid was added, and the mixture was heated to reflux for 2 hours. Water and ethyl acetate were added, the organic layer was separated, washed 3 times with saturated brine, and dried over anhydrous sodium sulfate. The solvent was distilled off under reduced pressure to obtain 8.2 g of 1-((trans-4- (formylmethyl) cyclohexyl) methoxy) -2,3-difluorobenzene.

(3-8) Synthesis of 1-((trans-4- (2-formylethyl) cyclohexyl) methoxy) -2,3-difluorobenzene
8.2 g of 1-((trans-4- (formylmethyl) cyclohexyl) methoxy) -2,3-difluorobenzene was dissolved in 50 mL of THF, and 12.6 g of methoxymethyltriphenylphosphonium chloride was added. Thereto was added dropwise a solution of 4.1 g of potassium-t-butoxide in THF (20 mL) at an internal temperature of 520 ° C. and stirred for 30 minutes. 10 mL of water was added and the solvent was distilled off under reduced pressure. Hexane and 50% aqueous methanol solution were added to separate the organic layer. This was washed with 50% aqueous methanol solution and saturated brine, and dried over silica gel. The solvent was distilled off under reduced pressure, the residue was dissolved in 50 mL of THF, 50 mL of 10% hydrochloric acid was added, and the mixture was heated to reflux for 2 hours. Water and ethyl acetate were added, the organic layer was separated, washed 3 times with saturated brine, and dried over anhydrous sodium sulfate. The solvent was distilled off under reduced pressure to obtain 7.0 g of 1-((trans-4- (2-formylethyl) cyclohexyl) methoxy) -2,3-difluorobenzene.

(3-9) Synthesis of 1-((trans-4- (3-butenyl) cyclohexyl) methoxy) -2,3-difluorobenzene
7.0 g of 1-((trans-4- (2-formylethyl) cyclohexyl) methoxy) -2,3-difluorobenzene was dissolved in 30 mL of THF, and 10.6 g of methyltriphenylphosphonium bromide was added. Thereto was added dropwise a solution of 3.3 g of potassium-t-butoxide in THF (15 mL) at an internal temperature of 520 ° C. and stirred for 30 minutes. 10 mL of water was added and the solvent was distilled off under reduced pressure. Hexane and 50% aqueous methanol solution were added to separate the organic layer. This was washed with 50% aqueous methanol solution and saturated brine, and subjected to column chromatography. The solvent was distilled off under reduced pressure to obtain 3.0 g of 1-((trans-4- (3-butenyl) cyclohexyl) methoxy) -2,3-difluorobenzene.

(3-10) Synthesis of 4-((trans-4- (3-butenyl) cyclohexyl) methoxy) -2,3-difluorophenol
Dissolve 3 g of 1-((trans-4- (3-butenyl) cyclohexyl) methoxy) -2,3-difluorobenzene in 30 mL of THF, and add 11.7 mL of sec-butyllithium (1.01 M cyclohexane, hexane solution). The solution was added dropwise at a temperature of -40 to -60 ° C and stirred for 30 minutes. Thereto was added 1.3 g of trimethyl borate, the temperature was raised to room temperature, 1.8 mL of 30% hydrogen peroxide was added, and the mixture was stirred at 40 ° C. for 1 hour. 5% Hydrochloric acid was added and stirred for 1 hour. Toluene was added and the organic layer was separated, washed with saturated brine, dried over anhydrous magnesium sulfate and dried with 4-((trans-4- (3-butenyl) cyclohexyl. ) Methoxy) -2,3-difluorophenol was obtained.

Synthesis of (3-11) 2,3-difluoro-1-((trans-4-ethylcyclohexyl) methoxy) -4-((trans-4- (3-butenyl) cyclohexyl) methoxy) benzene (1c)
The total amount of 4-((trans-4- (3-butenyl) cyclohexyl) methoxy) -2,3-difluorophenol obtained in (3-10) was dissolved in 20 mL of DMF, and 3.4 g of tripotassium phosphate and ( Trans-4-ethylcyclohexyl) methyl bromide (2.6 g) was added, and the mixture was stirred at 80 ° C. for 2 hours. Water and toluene were added, the organic layer was separated, washed with water and saturated brine, and dried over anhydrous magnesium sulfate, and the solvent was evaporated under reduced pressure. The residue was purified by recrystallization and column chromatography, and 2,3-difluoro-1-((trans-4-ethylcyclohexyl) methoxy) -4-((trans-4- (3-butenyl) cyclohexyl) as colorless crystals 1.3 g of methoxy) benzene (Ic) was obtained.
Phase transition temperature C 60.6 N 88.5 I
MS m / z: 420 (M ⁺ ), 146 (100)
¹ H-NMR (400 MHz, CDCl ₃ )
δ: 0.88 (t, J = 7.2 Hz, 3 H), 0.85 1.40 (m, 14 H), 1.70 2.20 (m, 12 H), 3.76 (d, J = 6.4 Hz, 4 H), 4.90 5.04 (m , 2 H), 5.75 5.87 (m, 1 H), 6.55 6.65 (m, 2 H)
(Example 4) Preparation of liquid crystal composition (1)
Host liquid crystal composition comprising the following composition (H)

Was prepared. Here, the physical properties of (H) are as follows.

Nematic phase upper limit temperature (TN-I): 103.2 ℃
Dielectric anisotropy (Δε): 0.03
Refractive index anisotropy (Δn): 0.099
Viscosity (mPa · s): 15.2
A liquid crystal composition (M-1) comprising 80% of the base liquid crystal (H) and 20% of (1a) obtained in Example 1 was prepared. The physical properties of this composition are as follows.

Nematic phase upper limit temperature (TN-I): 121.0 ℃
Dielectric anisotropy (Δε): −1.03
Refractive index anisotropy (Δn): 0.099
Viscosity (mPa · s): 23.4
The liquid crystal composition (M-1) containing the compound (1a) of the present invention has a significantly increased nematic phase upper limit temperature (TN-I) and dielectric anisotropy (Δε) compared to the base liquid crystal (H). Decreased to a negative value. This shows that the compound (Ia) of the present invention stably exhibits a nematic phase even at a high temperature, has a negative dielectric anisotropy, and has an extremely large absolute value.
(Example 5) Preparation of liquid crystal composition (2)
A liquid crystal composition (M-2) comprising 80% of the base liquid crystal (H) prepared in Example 4 and 20% of (1b) obtained in Example 2 was prepared. The physical properties of this composition are as follows.

Nematic phase upper limit temperature (TN-I): 97.3 ℃
Dielectric anisotropy (Δε): −1.20
Refractive index anisotropy (Δn): 0.097
Viscosity (mPa · s): 20.6
In the liquid crystal composition (M-2) containing the compound (1b) of the present invention, the dielectric anisotropy (Δε) was greatly reduced to a negative value as compared with the base liquid crystal (H). This shows that the compound (1b) of the present invention has a negative dielectric anisotropy and an extremely large absolute value.
(Example 6) Preparation of liquid crystal composition (3)
A liquid crystal composition (M-3) comprising 80% of the base liquid crystal (H) prepared in Example 4 and 20% of (1c) obtained in Example 3 was prepared. The physical properties of this composition are as follows.

Nematic phase upper limit temperature (TN-I): 99.3 ℃
Dielectric anisotropy (Δε): −1.09
Refractive index anisotropy (Δn): 0.096
Viscosity (mPa · s): 19.6
In the liquid crystal composition (M-3) containing the compound (Ic) of the present invention, the dielectric anisotropy (Δε) was greatly reduced to a negative value as compared with the base liquid crystal (H). This shows that the compound (1c) of the present invention has a negative dielectric anisotropy and an extremely large absolute value.
(Comparative Example 1)
80% of the base liquid crystal (H) prepared in Example 4 and the compound (R1) described in Patent Document 8

A liquid crystal composition (MR-1) comprising 20% was prepared. The physical properties of this composition are as follows.

Nematic phase upper limit temperature (TN-I): 109.2 ℃
Dielectric anisotropy (Δε): −1.19
Refractive index anisotropy (Δn): 0.095
Viscosity (mPa · s): 24.8
The physical properties of (M-2) in Example 5, (M-3) in Example 6 and (MR-1) in Comparative Example 1 are summarized in Table 1 below.

The liquid crystal composition (MR-1) containing the compound (R1) described in Patent Document 1 has a higher viscosity than the liquid crystal composition using the compound of the present invention. From this, it can be seen that the compound of the present invention has a negative dielectric anisotropy having a large absolute value and a low viscosity.
(Example 7) Preparation of liquid crystal composition (4)
A liquid crystal composition (M-4) represented by the following structure was prepared and measured for physical properties.

The physical properties of (M-4) were Tni: 81.2 ° C., Δn: 0.074, Δε: −4.7, and η: 22.2 mPa · s.
(Comparative Example 2)
As Comparative Example 2, a liquid crystal composition (MR-2) represented by the following structure which does not contain the compound represented by the general formula (I) was prepared and measured for physical properties.

The physical properties of (MR-2) were Tni: 77.5 ° C., Δn: 0.073, Δε: −4.8, η: 23.5 mPa · s.
(M-4) is an excellent liquid crystal composition having Δn equivalent to (MR-2) and negative Δε having a large absolute value, but having higher Tni and lower viscosity than (MR-2). I know that there is.
(Example 8) Preparation of liquid crystal composition (5)
A liquid crystal composition (M-5) represented by the following structure was prepared and measured for physical properties.

The physical properties of (M-5) were Tni: 79.5 ° C., Δn: 0.074, Δε: −4.7, η: 22.4 mPa · s.
(Example 9) Preparation of liquid crystal composition (6)
A liquid crystal composition (M-6) represented by the following structure was prepared and measured for physical properties.

The physical properties of (M-6) were Tni: 80.3 ° C., Δn: 0.074, Δε: −4.8, η: 19.0 mPa · s.
These physical property values are summarized in Table 2.

It is apparent that MR-2 is inferior in terms of liquid crystal phase upper limit temperature and viscosity as compared with M-4, M-5 and M-6.
(Example 10) Preparation of liquid crystal composition (7)
A liquid crystal composition (M-7) having the following composition was prepared as a composition having a slightly larger Δn.

The physical properties of (M-7) were as follows.
Nematic phase upper limit temperature (TN-I): 79.4 ℃
Dielectric anisotropy (Δε): −2.55
Refractive index anisotropy (Δn): 0.106
Viscosity (mPa · s): 24.4
(Example 11) Preparation of liquid crystal composition (8)
A liquid crystal composition (M-8) having the following composition was prepared as a composition having a slightly larger Δn.

The physical properties of (M-8) were as follows.
Nematic phase upper limit temperature (TN-I): 79.6 ℃
Dielectric anisotropy (Δε): −2.50
Refractive index anisotropy (Δn): 0.108
Viscosity (mPa · s): 24.6

Claims (12)

As the first component, the general formula (I)

(In the formula, R ¹ represents an alkyl group having 1 to 10 carbon atoms or an alkenyl group having 2 to 10 carbon atoms, and one CH ₂ group present in these groups or two or more non-adjacent CHs. _Two groups may be substituted with O and / or S, and one or more hydrogen atoms present in these groups may be substituted with F or Cl, and R ² has 1 to Represents an alkyl group having 10 carbon atoms, an alkoxyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, or an alkenyloxy group having 3 to 10 carbon atoms,
m represents 0, 1 or 2. )
Containing one or more compounds represented by:
As the second component, the general formula (II)

(Wherein R ³ and R ⁴ each independently represent the same meaning as R ² in formula (I),
B ¹ and B ² are each independently
(a) trans-1,4-cyclohexylene group (two CH ₂ groups not one CH ₂ group or adjacent present in this group may be substituted with an oxygen atom or a sulfur atom)
(b) 1,4-phenylene group (one or more CH groups present in this group may be substituted with a nitrogen atom)
(c) represents a group selected from the group consisting of a 1,4-cyclohexenylene group and a 1,4-bicyclo [2.2.2] octylene group, and the group (a), the group (b) or the group (c) May be substituted with CN or halogen,
Y ¹ and Y ² are independently
_{-CH 2 CH 2 -, - CH} = CH -, - CF 2 CF 2 -, - CF = CF -, - (CH 2) 4 -, - C≡C- or a single bond,
When there are a plurality of Y ² and B ² , they may be the same or different,
p represents 1 or 2. )
A nematic liquid crystal composition having a negative dielectric anisotropy containing one or more compounds represented by the formula: General formula (IA) and general formula (IB)

(In the formula, R ⁵ , R ⁶ , R ⁷ and R ⁸ represent the same meaning as R ² in the general formula (I).)
The nematic liquid crystal composition of Claim 1 containing the 1 type, or 2 or more types of compound chosen from the compound group represented by these. From general formula (II-A) to general formula (II-I)

(In the formula, R ¹³ , R ¹⁴ , R ¹⁵ , R ¹⁶ , R ¹⁷ , R ¹⁸ , R ¹⁹ , R ²⁰ , R ²¹ , R ²² , R ²³ , R ²⁴ , R ²⁵ , R ²⁶ , R ²⁷ , R ²⁸ , R ^29, and R ³⁰ represent the same meaning as R ² in the general formula (I), and contain one or more compounds selected from the group of compounds represented by claim 1 or 2. Nematic liquid crystal composition. 10 to 80% by mass of one or more compounds selected from the group consisting of general formula (IA) and general formula (IB), and from general formula (II-A) to general formula (II-I) The nematic liquid crystal composition according to claim 3, wherein the nematic liquid crystal composition contains 20 to 70% by mass of one or more compounds selected from the compound group consisting of: From general formula (III-A) to general formula (III-J)

(Wherein R ³¹ and R ³² each independently represents an alkyl group having 1 to 10 carbon atoms or an alkenyl group having 2 to 10 carbon atoms, and one CH ₂ group present in these groups or adjacent thereto. Two or more CH ₂ groups not present may be substituted with O and / or S, and one or more hydrogen atoms present in these groups may be substituted with F or Cl. )
The nematic liquid crystal composition according to claim 4, further comprising one or more compounds selected from the group consisting of: The dielectric anisotropy Δε at 25 ° C. is in the range of −2.0 to −8.0, the refractive index anisotropy Δn at 25 ° C. is in the range of 0.06 to 0.16, and the viscosity at 20 ° C. is in the range of 10 to 40 mPa · s. 6. The nematic liquid crystal composition according to claim 1, wherein the nematic phase-isotropic liquid phase transition temperature Tni is in the range of 70 ° C. to 130 ° C. 6. Formula (I-1)

(In the formula, R ^a represents a linear alkenyl group having 2 to 7 carbon atoms, and R ^b represents a linear alkyl group having 1 to 7 carbon atoms or a linear alkenyl group having 2 to 7 carbon atoms. P1 and p2 each independently represent 1 or 2, and the sum of p1 and p2 is 3 or less.) The compound according to claim 7, wherein in the general formula (I-1), R ^a represents ^a vinyl group and R ^b represents a linear alkyl group having 1 to 7 carbon atoms. A liquid crystal composition containing the compound according to claim 7 or 8. A liquid crystal display device using the nematic liquid crystal composition according to claim 1. A liquid crystal display element for active matrix driving using the nematic liquid crystal composition according to claim 1. A liquid crystal display element for VA mode, IPS mode or ECB mode, using the nematic liquid crystal composition according to claim 1.