JP5885017B2 - Azobenzene derivative and liquid crystal composition containing the same - Google Patents

Description

  The present invention relates to a compound having both an azobenzene structure and a biarylacetylene structure useful as an organic electronic material, medical pesticide, particularly a nematic liquid crystal material for electro-optical liquid crystal display, and a liquid crystal composition comprising the same, and a liquid crystal composition using the same The present invention relates to a liquid crystal display element.

  Liquid crystal display elements are used in various measuring instruments, automobile panels, word processors, electronic notebooks, printers, computers, televisions, watches, advertisement display boards, as well as watches and calculators. Typical liquid crystal display methods include TN (twisted nematic) type, STN (super twisted nematic) type, vertical alignment (VA: vertical alignment) type using TFT (thin film transistor), and IPS (inside).・ Plain switching type. In recent years, in these liquid crystal display elements, there is a tendency to achieve higher-speed driving by narrowing the cell gap (d) of the liquid crystal cell. Here, there is a constraint that the value (retardation) of the product (d × Δn) of the cell gap and the refractive index anisotropy (Δn) must be optimized. For this reason, if the cell gap is narrowed (d is decreased), the value of Δn must be increased. Thus, it is necessary to increase the Δn value of the liquid crystal composition, and a liquid crystal compound having a larger Δn value than the existing liquid crystal compounds is demanded.

  On the other hand, development of a cholesteric liquid crystal display element is underway as a new display method. A polarizing plate is required to configure the conventional display element described above, and a color filter is required to realize color display, but the presence of the polarizing plate not only reduces the light use efficiency, The viewing angle characteristics are adversely affected, and the presence of a color filter has a problem that the light use efficiency is lowered. In contrast, cholesteric liquid crystal display elements display light by selectively reflecting light having a wavelength corresponding to the helical pitch of cholesteric liquid crystal from circularly polarized light components contained in external light, eliminating the need for polarizing plates and color filters. The drawbacks of the conventional liquid crystal display element can be improved.

  In a cholesteric liquid crystal display element, a selective reflection state in a planar state in which the spiral axis is usually perpendicular to the substrate is used. At this time, it is known that the half-value width (Δλ) of the selectively reflected light is represented by the product (Δn × P) of Δn and the natural pitch (P), and in order to realize a bright display, a large Δn A compound having Therefore, development of a liquid crystal compound exhibiting a larger Δn value is also strongly desired for a liquid crystal composition for a cholesteric liquid crystal display element.

  A typical example of a liquid crystal compound exhibiting a large Δn value is a tolan compound. The compound represented by the formula (A) has a Δn value of 0.178 (Patent Document 1). The value of Δn can generally be increased by expanding the conjugated system in the molecular structure in the molecular long axis direction. For this reason, a compound represented by the formula (B) in which an aromatic ring is introduced into the compound represented by the formula (A) to further increase Δn was developed, and Δn showed 0.384 (Patent Document 2). ).

  Further, an azine-based compound represented by the formula (C) conjugated in a wide range has been developed, and this compound has Δn of 0.340 (Patent Document 3).

  However, even these conventionally developed compounds are insufficient to meet the above-mentioned demands, and it has been demanded to meet the demand for further higher Δn.

  Both the azobenzene structure and the tolan structure are known as structures exhibiting a large Δn, and a compound represented by the formula (D) has been reported as a material having both these structures (Patent Document 4). However, this compound has been developed as a pigment added to the liquid crystal composition, and there is no description regarding basic physical properties as a liquid crystal material such as Δn. For this reason, as will be described later, the present inventors actually synthesized an analog of this compound and measured the physical properties. As a result, it was found that Δn is still insufficient and cannot be practically used. Further, when used as a constituent component of a liquid crystal composition, there is a difficulty in practical use in that it is poor in solubility and compatibility with other compounds (group).

JP-A-61-5031 JP-A-60-152427 JP-A-11-71338 JP-A-2-56456

  The problem to be solved by the present invention is to provide a material realizing high Δn, and also a liquid crystal composition comprising the compound as a constituent member, and a liquid crystal display device and a cholesteric liquid crystal display device using the liquid crystal composition Is to provide.

  In order to solve the above-mentioned problems, the present inventors have intensively studied and found that the problems can be effectively solved by using a biarylacetylene compound into which an azobenzene moiety and a naphthalene structure are introduced, and have completed the present invention.

  The present invention provides a general formula (1)

Wherein R ¹ and R ² are each independently a fluorine atom, a chlorine atom, a cyano group, an alkyl group having 1 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, or 1 to 12 carbon atoms. Or an alkenyloxy group having 2 to 12 carbon atoms, but R ¹ and R ² do not both represent a substituent selected from a fluorine atom, a chlorine atom and a cyano group. In addition, one or two or more hydrogen atoms in the alkoxy group and / or alkenyloxy group may be each independently substituted with a fluorine atom, and one or two or more —CH _{2 in} these groups may be substituted. -Each independently may be substituted with -O-, -CO-, -COO- or -OCO- so that two or more oxygen atoms are not continuously bonded, and one or non- 2 adjacent More -CH ₂ - may be substituted with -CH = CH- or -C≡C- ^{independently,} Z 1, ^{Z 2} and ^{Z 3} each independently represent a single bond, -OCH ₂ - _{, -CH 2 O -, - C} 2 H 4 -, - C 4 H 8 -, - COO -, - OCO -, - CH = CH -, - CF = CF -, - CF 2 O -, - OCF 2 -, -CF ₂ CF ₂ -or -C≡C-, wherein A ¹ , A ² , A ³ , A ⁴ , A ⁵ and A ⁶ are each independently a 1,4-phenylene group, naphthalene-1, A 4-diyl group or a naphthalene-2,6-diyl group, wherein the hydrogen atoms in A ¹ , A ² , A ³ , A ⁴ , A ⁵ and A ⁶ are each independently substituted with a halogen atom. Well, one or more non-adjacent one or more —CH═ in A ¹ , A ² , A ³ , A ⁴ , A ⁵ and A ^{6 May} be substituted with -N =, but at least one of A ¹ , A ² , A ³ , A ⁴ , A ⁵ and A ^{6 present} is of the general formula (2)

(Wherein, X ¹ , X ² , X ³ , X ⁴ , X ⁵ and X ⁶ each independently represents a hydrogen atom or a halogen atom), and represents a naphthalene-2,6-diyl group represented by: m, n, and p each independently represent 0 or 1, but m + n + p represents 0-2. ), A liquid crystal composition containing the compound, a liquid crystal display device using the liquid crystal composition, a method for producing the compound represented by the general formula (1), and a raw material used in the production method in general Formula (3)

(In the formula, R ¹ is a fluorine atom, a chlorine atom, a cyano group, an alkyl group having 1 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or the number of carbon atoms. 2 to 12 alkenyloxy groups are represented, and one or two or more hydrogen atoms in the alkyl group, alkenyl group, alkoxy group and / or alkenyloxy group may be each independently substituted with a fluorine atom. Furthermore, one or more of —CH ₂ — in these groups are each independently —O—, —CO—, —COO— or —OCO so that two or more oxygen atoms are not continuously bonded. One or non-adjacent two or more —CH ₂ — in these groups may be each independently substituted with —CH═CH— or —C≡C—. ,
Z ¹ is a single bond, —OCH ₂ —, —CH ₂ O—, —C ₂ H ₄ —, —C ₄ H ₈ —, —COO—, —OCO—, —CH═CH—, —CF═CF—. _{, -CF 2 O -, - OCF} 2 -, - CF 2 CF 2 - or an -C≡C-, ^{a 1} is 1,4-phenylene group, a naphthalene-1,4-diyl group or a naphthalene-2,6 Represents a 6-diyl group, each hydrogen atom in A ¹ may be independently substituted with a halogen atom, and one or more non-adjacent —CH═ in A ¹ is —N═. X ¹ , X ² , X ³ , X ⁴ , X ⁵ and X ⁶ each independently represent a hydrogen atom or a halogen atom, and m represents 0 or 1. The compound represented by this is provided.

  The compound represented by the general formula (1) provided by the present invention is stable against heat, light, etc., has excellent liquid crystallinity, and can be easily produced industrially. The obtained compound represented by the general formula (1) has a very large Δn and exhibits a wide liquid crystal phase temperature range. In addition, the compound represented by the general formula (1) has good solubility and compatibility with other liquid crystal materials, but is more soluble particularly when a part of the ring structure is halogenated with a fluorine atom or the like. The compatibility is good, and it can be suitably used as a constituent component of the liquid crystal composition.

  Therefore, when added to a liquid crystal material for a liquid crystal display element that requires a large Δn, problems such as precipitation do not occur and the characteristics can be improved, so it is very useful as a component of the liquid crystal material for a liquid crystal display element. In particular, it is very useful as a component of a liquid crystal material for a cholesteric liquid crystal display element that requires a large Δn.

In the general formula (1), R ¹ and R ² may be the same or different, but an alkyl group having 1 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, or 1 carbon atom. It is preferable that it is a C12 alkoxy group, a C2-C12 alkenyloxy group, a fluorine atom, or a cyano group. In particular, to improve solubility, an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, an alkenyloxy group having 2 to 8 carbon atoms, A fluorine atom or R ³ —Z ⁴ — is preferable, and in order to improve liquid crystallinity, an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, or An alkenyloxy group having 2 to 8 carbon atoms is preferable. In order to increase the value of Δε, a fluorine atom or a cyano group is preferable. To further increase Δn, at least one of at least one of R ¹ and R ² is preferable. One of -CH ₂ - is preferably is substituted with -C = C-or ^-C≡C-, R 11 -C = C-or ^R 11 -C≡C- ^{(wherein, R 11} is a carbon atom Number 1-8 alkyl group or carbon atom Represents an alkenyl group having a number of 2 to 8, and R ¹¹ —C≡C— is preferable. The alkyl group, alkenyl group, alkoxy group and alkenyloxy group may be linear or branched, but are preferably linear. When branched, it may be substantially either the R or S form or the racemic form.

Z ¹ , Z ² and Z ³ are each independently a single bond, —OCH ₂ —, —CH ₂ O—, —C ₂ H ₄ —, —CH═CH—, —CF ₂ O—, —OCF ₂ —. Alternatively, —C≡C— is preferable, and a single bond, —OCH ₂ —, —CH ₂ O—, —CF ₂ O—, —OCF ₂ —, or —C≡C— is more preferable.

A ¹ , A ² , A ³ , A ⁴ , A ⁵ and A ⁶ each independently represents a 1,4-phenylene group, a naphthalene-1,4-diyl group or a naphthalene-2,6-diyl group; ¹ , A ² , A ³ , A ⁴ , A ⁵ and A ⁶ may be each independently substituted with a halogen atom, and A ¹ , A ² , A ³ , A ⁴ , A ⁵ and One or more non-adjacent —CH═ in A ⁶ may be substituted with —N═, but present in A ¹ , A ² , A ³ , A ⁴ , A ⁵ and A ⁶ . At least one of the general formula (2)

(Wherein, X ¹ , X ² , X ³ , X ⁴ , X ⁵ and X ⁶ each independently represents a hydrogen atom or a halogen atom), and a naphthalene-2,6-diyl group represented by: It is preferable that one or two or more of X ¹ , X ² , X ³ , X ⁴ , X ⁵ and X ^{6 in} the general formula (2) is a halogen atom, and X ¹ , X ² , X ³ , X ⁴ , X ⁵ and X ⁶ are more preferably fluorine atoms, and two or more of X ¹ , X ² , X ³ , X ⁴ , X ⁵ and X ⁶ are fluorine atoms. Is more preferable, two or more of X ¹ , X ³ , X ⁴ , and X ⁶ are more preferably a fluorine atom, and X ³ and X ⁴ are particularly preferably a fluorine atom.

At least one of A ¹ , A ² , A ³ , A ⁴ , A ⁵ and A ^{6 present} is a naphthalene-2,6-diyl group represented by the general formula (2), but the others are independent of each other. It is preferably a 1,4-phenylene group which is unsubstituted or optionally substituted by one or more fluorine atoms, and A ² is a naphthalene-2,6-diyl group represented by the general formula (2) And A ¹ , A ³ , A ⁴ , A ⁵ and A ⁶ are each independently a 1,4-phenylene group which is unsubstituted or may be substituted by one or more fluorine atoms. preferable.

In order to improve the compatibility, it is preferable that the hydrogen atom on the carbon atom adjacent to the carbon to which —C≡C— of A ² and / or A ³ is bonded is substituted with a fluorine atom. In particular, A ² is a naphthalene-2,6-diyl group represented by the general formula (2), X ³ and X ⁴ are fluorine atoms, and A ¹ , A ³ , A ⁴ , A ⁵ and A ⁶ Are each independently unsubstituted or a 1,4-phenylene group optionally substituted by one or more fluorine atoms.

  Since Δn exhibits a large value when the number of aromatic rings is large, m, n, and p are preferably 1 in order to increase Δn. However, when the number of aromatic rings is large, the phase with other liquid crystal materials is large. Solubility will decrease. For this reason, m + n + p is 2 or less, but m + n + p is preferably 1, and m + n + p is more preferably 0.

In the general formula (1), various types of compounds may be included depending on the selection of R ^{1 to} R ² , A ^{1 to} A ⁵ , Z ^{1 to} Z ³ , m, n, and p. In these, each compound represented by the following general formula (1-1)-general formula (1-44) is preferable.

(In the formula, R ^a and R ^b are each independently an alkyl group having 1 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or 2 to 2 carbon atoms. 12 alkenyloxy groups (one or two or more non-adjacent —CH ₂ — in R ^a and R ^b may each independently be substituted with —CH═CH— or —C≡C—). In the liquid crystal composition of the present invention, if the content of the compound represented by the general formula (1) is small, the effect does not appear. Therefore, the lower limit in the composition is 1% by mass (hereinafter referred to as composition). % In the product represents mass%.) It is preferably contained in an amount of preferably 2% by mass or more, and more preferably 5% by mass or more. Moreover, since it will cause problems, such as precipitation, if there is much content, as an upper limit, it is preferable to contain 50 mass% or less, it is more preferable to contain 30 mass% or less, and it is further containing 20 mass% or less. The content is preferably 10% by mass or less.

  In order to adjust the physical properties of the liquid crystal composition, a compound having no liquid crystal phase can be added as needed in addition to the compound having a liquid crystal phase.

  Thus, as a preferable representative example of the nematic liquid crystal compound that can be used by mixing with the compound represented by the general formula (1), in the composition provided by the present invention, the general formula is used as the first component. Although it contains at least one compound represented by (1), it is preferable to contain at least one of the following second to fourth components as other components.

  That is, the second component is a so-called fluorine-based (halogen-based) p-type liquid crystal compound, and one or more compounds selected from the compound group represented by the following general formulas (A1) to (A3) It is.

In the above formula, R ^b represents an alkyl group having 1 to 12 carbon atoms, which may be linear or have a methyl or ethyl branch, and has a 3- to 6-membered cyclic structure. Any —CH ₂ — present in the group may be —O—, —CH═CH—, —CH═CF—, —CF═CH—, —CF═CF— or —C≡C. Any hydrogen atom present in the group may be substituted by a fluorine atom or a trifluoromethoxy group, but a linear alkyl group having 1 to 7 carbon atoms, a carbon atom A linear 1-alkenyl group having 2 to 7 carbon atoms, a linear 3-alkenyl group having 4 to 7 carbon atoms, and a terminal group having 1 to 5 carbon atoms substituted with an alkoxy group having 1 to 3 carbon atoms Alkyl groups are preferred. Further, when asymmetric carbon is generated by branching, the compound may be optically active or racemic.

Ring A, Ring B, and Ring C may each independently be substituted with a trans-1,4-cyclohexylene group, a transdecahydronaphthalene-trans-2,6-diyl group, or one or more fluorine atoms. A good 1,4-phenylene group, a naphthalene-2,6-diyl group optionally substituted by one or more fluorine atoms, a tetrahydronaphthalene-2,6-optionally substituted by one or more fluorine atoms Diyl group, 1,4-cyclohexenylene group optionally substituted by a fluorine atom, 1,3-dioxane-trans-2,5-diyl group, pyrimidine-2,5-diyl group or pyridine-2,5 -Represents a diyl group, but may be a trans-1,4-cyclohexylene group, a transdecahydronaphthalene-trans-2,6-diyl group, or a naphth optionally substituted by a fluorine atom A talen-2,6-diyl group or a 1,4-phenylene group optionally substituted by 1 to 2 fluorine atoms is preferred. In particular, when ring B is a trans-1,4-cyclohexylene group or a transdecahydronaphthalene-trans-2,6-diyl group, ring A may be a trans-1,4-cyclohexylene group. Preferably, when ring C is a trans-1,4-cyclohexylene group or a transdecahydronaphthalene-trans-2,6-diyl group, ring B and ring A are trans-1,4-cyclohexylene groups. Preferably there is. In general formula (A3), ring A is preferably a trans-1,4-cyclohexylene group.
L ^a , L ^b and L ^c are each a linking group and each independently represents a single bond, an ethylene group (—CH ₂ CH ₂ —), a 1,2-propylene group (—CH (CH ₃ ) CH ₂ — and _{-CH 2 CH (CH 3) -} ), 1,4- butylene _{group, -COO -, - OCO -,} - OCF 2 -, - CF 2 O -, - CH = CH -, - CH = CF -, - CF═CH—, —CF═CF—, —C≡C— or —CH═NN═CH—, each represents a single bond, ethylene group, 1,4-butylene group, —COO—, —OCF ₂ —, —CF ₂ O—, —CF═CF— or —C≡C— are preferred, and a single bond or an ethylene group is particularly preferred. In addition, it is preferable that at least one of them in the general formula (A2) represents a single bond in the general formula (A3).

  Ring Z is an aromatic ring and can be represented by the following general formulas (La) to (Lc).

In the formula, Y ^{a to} Y ^j each independently represent a hydrogen atom or a fluorine atom. In the general formula (La), at least one of Y ^a and Y ^b is preferably a fluorine atom, and the general formula ( In Lb), at least one of Y ^{d to} Y ^f is preferably a fluorine atom, and more preferably Y ^d is a fluorine atom.

Terminal group P ^a represents a fluorine atom, a chlorine atom, trifluoromethoxy group, difluoromethoxy group, trifluoromethyl group or difluoromethyl group or 2 or more fluorine atoms optionally substituted carbon atoms 2 or 3 alkoxy groups, alkyl Represents a group, an alkenyl group or an alkenyloxy group, preferably a fluorine atom, a trifluoromethoxy group or a difluoromethoxy group, and particularly preferably a fluorine atom.

  Further, in the general formulas (A2) and (A3), the compound represented by the general formula (I) of the present invention is excluded.

  The third component is a so-called cyano p-type liquid crystal compound, and is one or more compounds selected from the group of compounds represented by the following general formulas (B1) to (B3).

In the above formula, R ^c represents an alkyl group having 1 to 12 carbon atoms, which may be linear or have a methyl or ethyl branch, and has a 3- to 6-membered cyclic structure. Any —CH ₂ — present in the group may be —O—, —CH═CH—, —CH═CF—, —CF═CH—, —CF═CF— or —C≡C. Any hydrogen atom present in the group may be substituted by a fluorine atom or a trifluoromethoxy group, a linear alkyl group having 1 to 7 carbon atoms, a carbon atom A linear 1-alkenyl group having 2 to 7 carbon atoms, a linear 3-alkenyl group having 4 to 7 carbon atoms, and a terminal group having 1 to 5 carbon atoms substituted with an alkoxy group having 1 to 3 carbon atoms Alkyl groups are preferred. Further, when asymmetric carbon is generated by branching, the compound may be optically active or racemic.

  Ring D, Ring E and Ring F may be each independently substituted with a trans-1,4-cyclohexylene group, a transdecahydronaphthalene-trans-2,6-diyl group, or one or more fluorine atoms. A good 1,4-phenylene group, a naphthalene-2,6-diyl group optionally substituted by one or more fluorine atoms, a tetrahydronaphthalene-2,6-optionally substituted by one or more fluorine atoms Diyl group, 1,4-cyclohexenylene group optionally substituted by a fluorine atom, 1,3-dioxane-trans-2,5-diyl group, pyrimidine-2,5-diyl group or pyridine-2,5 -Represents a diyl group, but is substituted by a trans-1,4-cyclohexylene group, a transdecahydronaphthalene-trans-2,6-diyl group, a fluorine atom The good can have a naphthalene-2,6-diyl group or one to two fluorine atoms may be substituted 1,4-phenylene group is preferred. In particular, when ring E is a trans-1,4-cyclohexylene group or a transdecahydronaphthalene-trans-2,6-diyl group, ring D may be a trans-1,4-cyclohexylene group. Preferably, when Ring F is a trans-1,4-cyclohexylene group or a transdecahydronaphthalene-trans-2,6-diyl group, Ring D and Ring E are trans-1,4-cyclohexylene groups. Preferably there is. In general formula (B3), ring D is preferably a trans-1,4-cyclohexylene group.

L ^d , ^Le and L ^f are each a linking group and each independently represents a single bond, an ethylene group (—CH ₂ CH ₂ —), a 1,2-propylene group (—CH (CH ₃ ) CH ₂ — and ) —CH ₂ CH (CH ₃ ) —), 1,4-butylene group, —COO—, —OCO—, —OCF ₂ —, —CF ₂ O—, —CH═CH—, —CH═CF—, —CF═CH—, —CF═CF—, —C≡C—, —OCH ₂ —, —CH ₂ O— or —CH═NN═CH— represents a single bond, ethylene group, —COO—, —OCF ₂ —, —CF ₂ O—, —CF═CF— or —C≡C— are preferred, and a single bond, an ethylene group or —COO— is particularly preferred. In the general formula (B2), at least one of them preferably represents a single bond. In the general formula (B3), at least two of them preferably represent a single bond.

Ring Y is an aromatic ring and can be represented by the following general formulas (L ^d ) to (L ^f ).

In the formula, Y ^{h to} Y ⁿ each independently represent a hydrogen atom or a fluorine atom, but in the general formula (Le), Y ⁿ and Y ^o are preferably hydrogen atoms.

The terminal group Pa represents ^a cyano group (—CN), a cyanate group (—OCN) or —C≡CCN, and is preferably a cyano group.

  Further, in the general formulas (B2) and (B3), the compound represented by the general formula (I) of the present invention is excluded.

  The fourth component is a so-called n-type liquid crystal having a dielectric anisotropy of about 0, and one or more compounds selected from the compound group represented by the following general formulas (C1) to (C3) It is.

In the above formula, R ^d and ^Pe each independently represent an alkyl group having 1 to 12 carbon atoms, which may be linear or have a methyl or ethyl branch, and 3 to 6 Any —CH ₂ — present in the group may be —O—, —CH═CH—, —CH═CF—, —CF═CH—, —CF═. Any hydrogen atom present in the group may be replaced by CF- or -C≡C-, and may be substituted by a fluorine atom or a trifluoromethoxy group. A linear alkyl group, a linear 1-alkenyl group having 2 to 7 carbon atoms, a linear 3-alkenyl group having 4 to 7 carbon atoms, a linear alkoxy group having 1 to 3 carbon atoms, or a terminal A linear alkyl group having 1 to 5 carbon atoms substituted by an alkoxy group having 1 to 3 carbon atoms And at least one is a linear alkyl group having 1 to 7 carbon atoms, a linear 1-alkenyl group having 2 to 7 carbon atoms, or a linear 3-alkenyl group having 4 to 7 carbon atoms. It is particularly preferred.

  Ring G, Ring H, Ring I and Ring J are each independently a trans-1,4-cyclohexylene group, a transdecahydronaphthalene-trans-2,6-diyl group, one or two fluorine atoms, 1,4-phenylene group optionally substituted by a methyl group, naphthalene-2,6-diyl group optionally substituted by one or more fluorine atoms, substituted by 1 or 2 fluorine atoms A tetrahydronaphthalene-2,6-diyl group, a 1,4-cyclohexenylene group optionally substituted by 1 to 2 fluorine atoms, a 1,3-dioxane-trans-2,5-diyl group, Represents a pyrimidine-2,5-diyl group or a pyridine-2,5-diyl group, but in each compound, a transdecahydronaphthalene-trans-2,6-diyl group, one or more A naphthalene-2,6-diyl group optionally substituted by a nitrogen atom, a tetrahydronaphthalene-2,6-diyl group optionally substituted by one or two fluorine atoms, and a fluorine atom The number of 1,4-cyclohexenylene group, 1,3-dioxane-trans-2,5-diyl group, pyrimidine-2,5-diyl group or pyridine-2,5-diyl group may be within 1 The other ring is preferably a trans-1,4-cyclohexylene group or a 1,4-phenylene group optionally substituted by 1 to 2 fluorine atoms or a methyl group.

L ^g , L ^h and ^Li are each a linking group, and each independently represents a single bond, an ethylene group (—CH ₂ CH ₂ —), a 1,2-propylene group (—CH (CH ₃ ) CH ₂ — and ) —CH ₂ CH (CH ₃ ) —), 1,4-butylene group, —COO—, —OCO—, —OCF ₂ —, —CF ₂ O—, —CH═CH—, —CH═CF—, —CF═CH—, —CF═CF—, —C≡C— or —CH═NN═CH—, each represents a single bond, ethylene group, 1,4-butylene group, —COO—, —OCO—, —OCF ₂ —, —CF ₂ O—, —CF═CF—, —C≡C— or —CH═NN═CH— are preferred, and in general formula (C2), at least one of them is represented by general formula (C3 ), At least two of them preferably represent a single bond.

  In the general formulas (C2) and (C3), the compound represented by the general formula (I) of the present invention is excluded.

  More preferable forms in the general formula (C1) can be represented by the following general formulas (C1a) to (C1h).

In the above formulas, R ^f and R ^g are each independently a linear alkyl group having 1 to 7 carbon atoms, a linear 1-alkenyl group having 2 to 7 carbon atoms, or 4 to 7 carbon atoms. A linear 3-alkenyl group, a linear alkoxy group having 1 to 3 carbon atoms, or a linear alkyl group having 1 to 5 carbon atoms, the terminal of which is substituted with an alkoxy group having 1 to 3 carbon atoms is represented. However, at least one represents a linear alkyl group having 1 to 7 carbon atoms, a linear 1-alkenyl group having 2 to 7 carbon atoms, or a linear 3-alkenyl group having 4 to 7 carbon atoms. However, if the ring G1~ ring G3 is an aromatic ring, the corresponding ^{R f} is except 1-alkenyl group and alkoxy group, and when ring H1~ ring and H3 of the aromatic ring, the corresponding ^{R g} is 1-alkenyl and alkoxy Excluding groups.

  Ring G1 and Ring H1 are each independently substituted with a trans-1,4-cyclohexylene group, a transdecahydronaphthalene-trans-2,6-diyl group, one or two fluorine atoms or a methyl group. 1,4-phenylene group, naphthalene-2,6-diyl group optionally substituted by one or more fluorine atoms, tetrahydronaphthalene-2 optionally substituted by 1 to 2 fluorine atoms, 6-diyl group, 1,4-cyclohexenylene group optionally substituted by 1 to 2 fluorine atoms, 1,3-dioxane-trans-2,5-diyl group, pyrimidine-2,5-diyl Group or a pyridine-2,5-diyl group, but in each compound, a transdecahydronaphthalene-trans-2,6-diyl group, one or more fluorine atoms A more optionally substituted naphthalene-2,6-diyl group, a tetrahydronaphthalene-2,6-diyl group optionally substituted by 1 to 2 fluorine atoms, and an optionally substituted 1 atom , 4-cyclohexenylene group, 1,3-dioxane-trans-2,5-diyl group, pyrimidine-2,5-diyl group or pyridine-2,5-diyl group is preferably within one, In this case, the other ring is a trans-1,4-cyclohexylene group or a 1,4-phenylene group optionally substituted by 1 to 2 fluorine atoms or a methyl group. Ring G2 and Ring H2 are each independently substituted with a trans-1,4-cyclohexylene group, transdecahydronaphthalene-trans-2,6-diyl group, 1 to 2 fluorine atoms or a methyl group. 1,4-phenylene group, naphthalene-2,6-diyl group optionally substituted by one or more fluorine atoms, tetrahydronaphthalene-2 optionally substituted by 1 to 2 fluorine atoms, Represents a 6-diyl group, but in each compound, a transdecahydronaphthalene-trans-2,6-diyl group, a naphthalene-2,6-diyl group optionally substituted by one or more fluorine atoms, The number of tetrahydronaphthalene-2,6-diyl groups which may be substituted by two fluorine atoms is preferably no more than one. The other ring is a trans-1,4-cyclohexylene group or a 1,4-phenylene group optionally substituted by 1 to 2 fluorine atoms or a methyl group. Ring G3 and Ring H3 are each independently a 1,4-phenylene group optionally substituted by 1 to 2 fluorine atoms or a methyl group, and naphthalene-2 optionally substituted by one or more fluorine atoms , 6-diyl group, tetrahydronaphthalene-2,6-diyl group optionally substituted by 1 or 2 fluorine atoms, naphthalene optionally substituted by one or more fluorine atoms in each compound It is preferable that the number of the -2,6-diyl group and the tetrahydronaphthalene-2,6-diyl group optionally substituted by 1 or 2 fluorine atoms is 1 or less.

  More preferable forms in the general formula (C2) can be represented by the following general formulas (C2a) to (C2m).

In the above formula, ring G1, ring G2, ring G3, ring H1, ring H2, and ring H3 have the same meanings as described above, ring I1 is the same as ring G1, ring I2 is the same as ring G2, and ring I3 is the same as ring G3. Represents meaning. In each of the above compounds, a transdecahydronaphthalene-trans-2,6-diyl group, a naphthalene-2,6-diyl group optionally substituted by one or more fluorine atoms, and one or two fluorine atoms A tetrahydronaphthalene-2,6-diyl group optionally substituted by 1, a 1,4-cyclohexenylene group optionally substituted by a fluorine atom, a 1,3-dioxane-trans-2,5-diyl group, The number of pyrimidine-2,5-diyl groups or pyridine-2,5-diyl groups is preferably 1 or less, and the other ring in that case is a trans-1,4-cyclohexylene group or 1 to 2 groups. A 1,4-phenylene group which may be substituted with a fluorine atom or a methyl group.
Next, the more preferable form in (C3) can be represented by the following general formulas (C3a) to (C3f).

  In the above formula, ring G1, ring G2, ring H1, ring H2, ring I1 and ring I2 have the same meanings as described above, and ring J1 has the same meaning as ring G1 or ring J2, respectively. In each of the above compounds, a transdecahydronaphthalene-trans-2,6-diyl group, a naphthalene-2,6-diyl group optionally substituted by one or more fluorine atoms, and one or two fluorine atoms A tetrahydronaphthalene-2,6-diyl group optionally substituted by 1, a 1,4-cyclohexenylene group optionally substituted by a fluorine atom, a 1,3-dioxane-trans-2,5-diyl group, The number of pyrimidine-2,5-diyl groups or pyridine-2,5-diyl groups is preferably 1 or less, and the other ring in that case is a trans-1,4-cyclohexylene group or 1 to 2 groups. A 1,4-phenylene group which may be substituted with a fluorine atom or a methyl group.

In the present invention, the compound of the general formula (1) can be produced, for example, as follows, but the spirit and scope of the present invention are not limited thereto.
(Manufacturing method 1) General formula (7)

(Wherein R ¹ , A ¹ , A ² , Z ¹ and m each independently represent the same meaning as in the general formula (1), X is a chlorine atom, a bromine atom, an iodine atom, a benzenesulfonyloxy group, p A compound represented by -toluenesulfonyloxy group, methanesulfonyloxy group or trifluoromethanesulfonyloxy group) and trimethylsilylacetylene, tetrakistriphenylphosphine palladium (0), palladium (II) acetate or bis (trichloride) In the presence of a palladium-based transition metal catalyst such as phenylphosphine) palladium (II), the Sonogashira reaction is carried out in the presence of a base and a copper salt, thereby obtaining

(Wherein R ¹ , A ¹ , A ² , Z ¹ and m each independently represent the same meaning as in general formula (1), and TMS represents a trimethylsilyl group) to obtain a compound represented by it can.

  Examples of the base include butylamine, diethylamine, triethylamine, diisopropylamine, piperidine, ammonia and the like, preferably triethylamine and diisopropylamine. Preferred examples of the copper salt include copper (I) iodide and copper (I) bromide. X can be exemplified by bromine, iodine and trifluoromethanesulfonyloxy groups, with iodine and trifluoromethanesulfonyloxy groups being particularly preferred.

  Any solvent can be used as long as it allows the reaction to proceed appropriately. Ether solvents, hydrocarbon solvents, aromatic solvents, polar solvents, and the like can be preferably used, and amines used as bases can also be used. Can also be used as a solvent. Ether solvents include 1,4-dioxane, 1,3-dioxane, tetrahydrofuran, diethyl ether, t-butyl methyl ether, etc., and hydrocarbon solvents include pentane, hexane, cyclohexane, heptane, octane, etc. Benzene, toluene, xylene, mesitylene, chlorobenzene, dichlorobenzene, etc. as group solvents, N, N-dimethylformamide, N, N-dimethylacetamide, N-methylpyrrolidone, dimethyl sulfoxide, sulfolane, water, etc. as polar solvents Can be cited as a good example. Of these, tetrahydrofuran, N, N-dimethylformamide, N, N-dimethylacetamide and the like are preferable. Each of the above solvents may be used alone, or two or more solvents may be mixed and used.

  The reaction temperature can be in the range from the freezing point of the solvent to the reflux temperature, but is preferably 20 ° C to 90 ° C.

  Next, the compound represented by the general formula (8) is deprotected using tetrabutylammonium fluoride or the like, and the general formula (9)

(Wherein, R ¹ , A ¹ , A ² , Z ¹ and m each independently represent the same meaning as in general formula (1)) can be obtained.

  Any solvent can be used as long as it allows the reaction to proceed appropriately, but ether solvents, hydrocarbon solvents, aromatic solvents, and the like can be preferably used. Ether solvents include 1,4-dioxane, 1,3-dioxane, tetrahydrofuran, diethyl ether, t-butyl methyl ether, etc., and hydrocarbon solvents include pentane, hexane, cyclohexane, heptane, octane, etc. Examples of the group solvent include benzene, toluene, xylene, mesitylene and the like. Of these, ether solvents such as 1,4-dioxane and tetrahydrofuran are preferred. Each of the above solvents may be used alone, or two or more solvents may be mixed and used.

  Although reaction temperature can be performed in the recirculation | reflux temperature range from the freezing point of a solvent, -40 degreeC to 30 degreeC is preferable.

  Next, general formula (10)

(Wherein R ² , A ⁵ , A ⁶ , Z ³ and p independently represent the same meaning as in general formula (1)) and sodium nitrite were reacted under acidic conditions. After, general formula (11)

(Wherein A ³ , A ⁴ , Z ² and n each independently represent the same meaning as in general formula (1)) and a diazo coupling reaction under basic conditions with a compound represented by the general formula (12)

(Wherein R ² , A ^{3 to} A ⁶ , Z ² , Z ³ , n and p each independently represent the same meaning as in general formula (1)) can be obtained.

  As the acid used for the acidic condition, an inorganic acid is preferably used, and hydrochloric acid, sulfuric acid and the like are particularly preferable. As a base used for making it basic, an inorganic base is preferably used, and sodium hydroxide, potassium hydroxide, sodium carbonate, and sodium bicarbonate are particularly preferable.

  Any solvent can be used as long as it allows the reaction to proceed suitably, but ether solvents, hydrocarbon solvents, polar solvents, and the like can be preferably used. Ether solvents include 1,4-dioxane, 1,3-dioxane, tetrahydrofuran, diethyl ether, t-butyl methyl ether, etc., and hydrocarbon solvents include pentane, hexane, cyclohexane, heptane, octane, etc., polar Examples of the solvent include methanol, ethanol, propanol, water and the like. Among these, water-soluble ether solvents such as 1,4-dioxane and tetrahydrofuran and water are preferable. Each of the above solvents may be used alone, or two or more solvents may be mixed and used.

  Although reaction temperature can be performed in the recirculation | reflux temperature range from the freezing point of a solvent, -40 degreeC to 10 degreeC is preferable.

  Next, the compound represented by the general formula (12) is reacted with trifluoromethanesulfonic anhydride in the presence of a base, and the general formula (13)

(Wherein R ² , A ^{3 to} A ⁶ , Z ² , Z ³ , n and p each independently represent the same meaning as in general formula (1), and Tf represents a trifluoromethanesulfonyl group). Can be obtained.

  As the base, amines are preferably used, and triethylamine, diisopropylamine, and pyridine are particularly preferable.

  Any solvent may be used as long as it allows the reaction to proceed suitably. Ether solvents, hydrocarbon solvents, aromatic solvents, chlorine solvents, and the like can be preferably used. Ether solvents include 1,4-dioxane, 1,3-dioxane, tetrahydrofuran, diethyl ether, t-butyl methyl ether, etc., and hydrocarbon solvents include pentane, hexane, cyclohexane, heptane, octane, etc. Examples of the group solvent include benzene, toluene, xylene, mesitylene and the like, and examples of the chlorine solvent include dichloromethane, chloroform, 1,2-dichloroethane and the like. Of these, chlorinated solvents such as dichloromethane, chloroform, and 1,2-dichloroethane are preferable. Each of the above solvents may be used alone, or two or more solvents may be mixed and used.

  Although reaction temperature can be performed in the recirculation | reflux temperature range from the freezing point of a solvent, -40 degreeC to 10 degreeC is preferable.

  Next, the compound represented by the general formula (13) and the compound represented by the general formula (9) are converted into tetrakistriphenylphosphine palladium (0), palladium (II) acetate or bis (triphenylphosphine) palladium dichloride. A compound represented by the general formula (1) can be obtained by performing a coupling reaction in the presence of a base and a copper salt in the presence of a palladium-based transition metal catalyst such as (II).

  Examples of preferred bases include butylamine, diethylamine, triethylamine, diisopropylamine, piperidine, and ammonia. Among them, triethylamine and diisopropylamine are preferred. Preferred examples of the copper salt include copper (I) iodide and copper (I) bromide.

  Any solvent can be used as long as it allows the reaction to proceed suitably. Ether solvents, hydrocarbon solvents, aromatic solvents, polar solvents, and the like can be preferably used, and the amine used as the base can be selected. It can also be used as a solvent. Ether solvents include 1,4-dioxane, 1,3-dioxane, tetrahydrofuran, diethyl ether, t-butyl methyl ether, etc., and hydrocarbon solvents include pentane, hexane, cyclohexane, heptane, octane, etc. Benzene, toluene, xylene, mesitylene, chlorobenzene, dichlorobenzene, etc. as group solvents, N, N-dimethylformamide, N, N-dimethylacetamide, N-methylpyrrolidone, dimethyl sulfoxide, sulfolane, water, etc. as polar solvents Can be cited as a good example. Of these, polar solvents such as tetrahydrofuran, N, N-dimethylformamide and N, N-dimethylacetamide are preferred. Each of the above solvents may be used alone, or two or more solvents may be mixed and used.

The reaction temperature can be in the range from the freezing point of the solvent to the reflux temperature, but is preferably 20 ° C to 120 ° C.
(Manufacturing method 2) The compound represented by General formula (9) obtained by manufacturing method 1, and General formula (14)

(Wherein A ³ , A ⁴ , Z ² and n each independently represent the same meaning as in general formula (1), X is a chlorine atom, a bromine atom, an iodine atom, a benzenesulfonyloxy group, p-toluenesulfonyl) An oxy group, a methanesulfonyloxy group or a trifluoromethanesulfonyloxy group) and tetrakistriphenylphosphine palladium (0), palladium (II) acetate or bis (triphenylphosphine) palladium (II) chloride In the presence of a palladium-based transition metal catalyst such as a base and a copper salt in the presence of a Sonogashira reaction,

(Wherein R ¹ , A ^{1 to} A ⁴ , Z ¹ , Z ² , m and n each independently represent the same meaning as in general formula (1)) can be obtained.

  Examples of the base include butylamine, diethylamine, triethylamine, diisopropylamine, piperidine, and ammonia, preferably triethylamine, diisopropylamine, and ammonia. Preferred examples of the copper salt include copper (I) iodide and copper (I) bromide. Preferred examples of X include bromine, iodine and trifluoromethanesulfonyloxy groups, with iodine and trifluoromethanesulfonyloxy groups being more preferred.

  Any solvent can be used as long as it allows the reaction to proceed suitably. Ether solvents, hydrocarbon solvents, aromatic solvents, polar solvents, and the like can be preferably used, and the amine used as the base can be selected. It can also be used as a solvent. Ether solvents include 1,4-dioxane, 1,3-dioxane, tetrahydrofuran, diethyl ether, t-butyl methyl ether, etc., and hydrocarbon solvents include pentane, hexane, cyclohexane, heptane, octane, etc. Benzene, toluene, xylene, mesitylene, chlorobenzene, dichlorobenzene, etc. as group solvents, N, N-dimethylformamide, N, N-dimethylacetamide, N-methylpyrrolidone, dimethyl sulfoxide, sulfolane, water, etc. as polar solvents Can be cited as a good example. Of these, polar solvents such as tetrahydrofuran, N, N-dimethylformamide, N, N-dimethylacetamide, and water are preferable. Each of the above solvents may be used alone, or two or more solvents may be mixed and used.

  The reaction temperature can be in the range from the freezing point of the solvent to the reflux temperature, but is preferably 20 ° C to 120 ° C.

  Next, after reacting the compound represented by the general formula (15) and sodium nitrite under acidic conditions, the general formula (16)

(Wherein A ⁵ , A ⁶ , Z ³ and p each independently represent the same meaning as in general formula (1)) and a diazo coupling reaction under basic conditions with a compound represented by the general formula (17)

(Wherein R ¹ , A ^{1 to} A ⁶ , Z ^{1 to} Z ³ , m, n, and p each independently represent the same meaning as in general formula (1)). it can.

  As the acid used for the acidic condition, an inorganic acid is preferably used, and hydrochloric acid, sulfuric acid and the like are particularly preferable. As the base used for basic conditions, an inorganic base is preferably used, and sodium hydroxide, potassium hydroxide, sodium carbonate, and sodium hydrogen carbonate are particularly preferable.

  Any solvent can be used as long as it allows the reaction to proceed suitably, but ether solvents, hydrocarbon solvents, polar solvents, and the like can be preferably used. Ether solvents include 1,4-dioxane, 1,3-dioxane, tetrahydrofuran, diethyl ether, t-butyl methyl ether, etc., and hydrocarbon solvents include pentane, hexane, cyclohexane, heptane, octane, etc., polar Examples of the solvent include methanol, ethanol, propanol, water and the like. Among these, water-soluble ether solvents such as 1,4-dioxane and tetrahydrofuran and water are preferable. Each of the above solvents may be used alone, or two or more solvents may be mixed and used.

  Although reaction temperature can be performed in the recirculation | reflux temperature range from the freezing point of a solvent, -40 degreeC to 10 degreeC is preferable.

  Next, the compound represented by the general formula (17) and the general formula (18)

(In the formula, R ⁴ represents an alkyl group having 1 to 12 carbon atoms or an alkenyl group having 2 to 12 carbon atoms, and X represents a chlorine atom, a bromine atom, an iodine atom, a benzenesulfonyloxy group, or p-toluenesulfonyloxy. Group, a methanesulfonyloxy group or a trifluoromethanesulfonyloxy group) is reacted in the presence of a base to give a general formula (19)

(In the formula, R ¹ , A ^{1 to} A ⁶ , Z ^{1 to} Z ³ , m, n and p each independently represent the same meaning as in general formula (1), and R ⁴ has 1 to 12 carbon atoms. An alkyl group or an alkenyl group having 2 to 12 carbon atoms can be obtained.

  As the base, sodium hydroxide, potassium hydroxide, sodium carbonate, sodium hydrogen carbonate, potassium hydrogen carbonate, potassium carbonate and the like can be preferably used.

  Any solvent can be used as long as it allows the reaction to proceed suitably, but ether solvents, hydrocarbon solvents, polar solvents, and the like can be preferably used. Ether solvents include 1,4-dioxane, 1,3-dioxane, tetrahydrofuran, diethyl ether, t-butyl methyl ether, etc., and hydrocarbon solvents include pentane, hexane, cyclohexane, heptane, octane, etc., polar Preferred examples of the solvent include N, N-dimethylformamide, N, N-dimethylacetamide, N-methylpyrrolidone, acetone, acetonitrile and the like. Of these, ether solvents such as 1,4-dioxane and tetrahydrofuran and polar solvents such as N, N-dimethylformamide, N, N-dimethylacetamide and acetone are preferable. Each of the above solvents may be used alone, or two or more solvents may be mixed and used.

  The reaction temperature can be in the range from the freezing point of the solvent to the reflux temperature, but is preferably 20 ° C to 130 ° C.

  EXAMPLES Hereinafter, although an Example is given and this invention is further explained in full detail, this invention is not limited to these Examples.

  “%” In the compositions of the following examples and comparative examples means “mass%”.

Various analyzes were performed by the following methods.
-Phase transition temperature: measured with a polarizing microscope equipped with a temperature control stage-Compound structure: confirmed by nuclear magnetic resonance spectrum (NMR), mass spectrum (MS), etc. _TN-I represents the upper limit temperature indicating a nematic phase .

  The following abbreviations are used in compound descriptions.

THF: Tetrahydrofuran DMF: N, N-dimethylformamide TMS: Trimethylsilyl group Tf: Trifluoromethanesulfonyl group Et: Ethyl group Pr: n-propyl group Bu: n-butyl group Pen: n-pentyl group (Example 1) 4- Preparation of (6-propyl-1,3-difluoronaphthalen-2-yl) ethynyl-4'-ethylazobenzene

  15 g of 5,7-difluoro-1,2,3,4-tetrahydronaphthalen-2-one (obtained in the same manner as described in JP 2002-128717 A) was dissolved in 75 mL of dichloromethane, 23.7 g of bromine dissolved in 190 mL of dichloromethane was added dropwise at 4-5 ° C. over 3 hours. After stirring at 15 ° C. or lower for 50 minutes, a saturated aqueous sodium hydrogen sulfite solution was added under ice cooling to deactivate excess bromine. The organic layer was washed in turn with water, saturated aqueous sodium hydrogen carbonate, and saturated brine, dried over anhydrous magnesium sulfate, filtered, and concentrated. Next, this was dissolved in 260 mL of ethanol and 50 mL of triethylamine, 2.9 g of 5% palladium carbon (containing 50% water) (Pd / C) was added, and the mixture was stirred at room temperature for 6 hours under a hydrogen pressure of 0.5 MPa. After filtration and concentration, the residue was dissolved in 150 mL of dichloromethane, washed successively with 10% hydrochloric acid, saturated aqueous sodium hydrogen carbonate, and saturated brine, dried over anhydrous magnesium sulfate, filtered, and concentrated. Recrystallization from a mixed solvent of toluene / hexane gave 8.9 g of 5,7-difluoro-2-naphthol.

  8.9 g of 5,7-difluoro-2-naphthol obtained is dissolved in 5.9 g of pyridine, 50 mL of dichloromethane. 15.4 g of trifluoromethanesulfonic anhydride dissolved in 45 mL of dichloromethane was added dropwise thereto at 6-8 ° C. over 1 hour, and the mixture was further stirred at room temperature or lower for 1 hour. 50 mL of water was added under ice-cooling, and the organic layer was separated, washed successively with water, 10% hydrochloric acid and saturated brine, dried over anhydrous magnesium sulfate, filtered and concentrated. Purification by silica gel column chromatography (eluent hexane / ethyl acetate) gave 15.0 g of 5,7-difluoronaphthalen-2-yl trifluoromethanesulfonate as a solid.

  15.0 g of obtained trifluoromethanesulfonic acid 5,7-difluoronaphthalen-2-yl, 0.2 g of copper (I) iodide, 1.4 g of tetrakis (triphenylphosphine) palladium (0), 90 mL of DMF, 30 mL Of triethylamine was mixed, and 2 L of propyne was blown in gradually so as to keep the temperature below 50 ° C. The mixture was cooled to 20 ° C. or lower and acidified with 10% hydrochloric acid. A hexane / toluene mixed solution was added and the mixture was filtered through celite. The organic layer was washed with water, 10% hydrochloric acid and saturated brine in this order, dried over anhydrous magnesium sulfate, filtered and concentrated. Purification by silica gel column chromatography (eluent toluene) gave 9.7 g of 2- (1-propynyl) -5,7-difluoronaphthalene.

  9.7 g of 2- (1-propynyl) -5,7-difluoronaphthalene obtained was dissolved in 180 mL of ethyl acetate, 2.4 g of 5% palladium carbon (containing 50% water) was added, and under a hydrogen pressure of 0.5 MPa, Stir at room temperature for 2 days. Filtration and concentration gave 9.5 g of 2-propyl-5,7-difluoronaphthalene as a pale yellow oil.

  The obtained 9.5 g of 2-propyl-5,7-difluoronaphthalene was dissolved in 66 mL of THF. 32 mL of n-butyllithium 1.6M hexane solution was added dropwise at −44 to −60 ° C. over 7 minutes, and the mixture was further stirred for 20 minutes. 12.8 g of iodine dissolved in 39 mL of THF was added dropwise at −62 to −49 ° C. over 20 minutes, and the mixture was further stirred at −60 for 1 hour. After adding 70 mL of 10% hydrochloric acid, heating to 0 ° C. and extracting with toluene, the organic layer was washed with water and then saturated brine, dried over anhydrous magnesium sulfate, filtered, concentrated, and 15.4 g of 2 -Propyl-5,7-difluoro-6-iodonaphthalene was obtained.

  The resulting 15.4 g 2-propyl-5,7-difluoro-6-iodonaphthalene, 0.35 g copper iodide, 1.1 g tetrakis (triphenylphosphine) palladium (0) in 45 mL DMF, 15 mL triethylamine. The mixture was mixed and heated to 70 ° C., 5.5 g of trimethylsilylacetylene was added dropwise, and the mixture was further stirred at 70 to 80 ° C. for 10 hours. After cooling, water and toluene were added and stirred, and then the organic phase was separated. The aqueous phase was extracted with toluene, and the organic phases were combined, washed successively with 10% hydrochloric acid, saturated aqueous sodium hydrogen carbonate and saturated brine, dried over anhydrous sodium sulfate, and the solvent was evaporated under reduced pressure. Purification by column chromatography gave 13.3 g of 2-propyl-6- (trimethylsilyl) ethynyl-5,7-difluoronaphthalene.

13.3 g of the obtained 2-propyl-6- (trimethylsilyl) ethynyl-5,7-difluoronaphthalene was dissolved in 50 mL of THF, and 48 mL of tetrabutylammonium fluoride was added thereto at such a rate that the reaction temperature was 10 ° C. or less. 1.0M THF solution was added dropwise, and the mixture was further stirred at room temperature for 1 hour. Water was added and stirred to separate the organic phase. The aqueous phase was extracted with hexane, the organic phases were combined, washed with saturated brine, dried over anhydrous sodium sulfate, and the solvent was distilled off under reduced pressure. Purification by column chromatography gave 9.9 g of 2-propyl-6-ethynyl-5,7-difluoronaphthalene.
Using 14.7 g of 4'-ethylazobenzene-4-yl trifluoromethanesulfonate (4-ethyl-4'-hydroxyazobenzene (obtained in the same manner as described in Chemical Communication, 2010, 46, 2587-2589) Obtained in the same manner as in the case of 5,7-difluoronaphthalen-2-yl trifluoromethanesulfonate), 0.33 g of copper (I) iodide, 1.0 g of tetrakis (triphenylphosphine) palladium (0) Is mixed with 50 mL of DMF and 20 mL of triethylamine, heated to 75 ° C., and 9.9 g of 2-propyl-6-ethynyl-5,7-difluoronaphthalene obtained here is dissolved in 30 mL of DMF and added dropwise. Stir for 7 hours. After cooling to room temperature, toluene and 10% hydrochloric acid were added to the reaction mixture until the system became acidic, and the mixture was stirred to separate the organic phase. The aqueous phase was extracted with toluene, the organic phases were combined, washed with saturated aqueous sodium hydrogen carbonate and saturated brine, dried over anhydrous sodium sulfate, and the solvent was evaporated under reduced pressure. Purification by column chromatography and recrystallization (acetone, methanol) gave 9.5 g of 4- (6-propyl-1,3-difluoronaphthalen-2-yl) ethynyl-4′-ethylazobenzene.

MS m / z: 438 [M +]
Similarly, the following compounds were obtained.
4- (6-Propyl-1,3-difluoronaphthalen-2-yl) ethynyl-4'-propylazobenzene
4- (6-Ethyl-1,3-difluoronaphthalen-2-yl) ethynyl-4'-propylazobenzene
4- (6-Ethyl-1,3-difluoronaphthalen-2-yl) ethynyl-4'-ethylazobenzene (Example 2) 4- (6-Propyl-1,3-difluoronaphthalen-2-yl) ethynyl- Production of 4'-ethoxyazobenzene

  In a suspension of 17.1 g iodoaniline, 0.3 g copper iodide, 0.6 g bis (triphenylphosphine) palladium (II) dichloride, 160 mL 1 M aqueous ammonia, 180 mL THF, 20 g 2-propyl-6 -Ethynyl-5,7-difluoronaphthalene (obtained in the same manner as in Example 1) was dissolved in 20 mL of THF, added dropwise at 40 ° C., and further stirred for 4 hours. Saturated saline was added, and the organic layer was separated. The aqueous layer was extracted with THF, the organic layers were combined, washed with saturated brine, dried over anhydrous sodium sulfate, and the solvent was evaporated under reduced pressure. Purified by column chromatography, then dissolved in THF, 6M hydrochloric acid was added, the organic layer was separated, washed with saturated brine, dried over anhydrous sodium sulfate, the solvent was distilled off under reduced pressure, and 25.2 g of 4 -(6-Propyl-1,3-difluoronaphthalen-2-yl) ethynylaniline hydrochloride was obtained.

  25.2 g of the obtained 4- (6-propyl-1,3-difluoronaphthalen-2-yl) ethynylaniline hydrochloride, 10 mL of concentrated hydrochloric acid, 260 mL of THF were mixed, and 5.4 g of sodium nitrite was mixed there. Was dissolved in 30 mL of water and added dropwise under ice cooling, and the mixture was further stirred for 1 hour to prepare a diazonium salt solution. 7.5 g of phenol, 7.9 g of sodium carbonate, and 3.2 g of sodium hydroxide were dissolved in 120 mL of water, and the prepared diazonium solution was added dropwise under ice cooling, followed by further stirring for 3 hours. 50 mL of 15% hydrochloric acid was added, followed by extraction with THF. The organic layer was washed with saturated brine, dried over anhydrous sodium sulfate, and the solvent was evaporated under reduced pressure. Purification by column chromatography and recrystallization gave 14.3 g of 4- (6-propyl-1,3-difluoronaphthalen-2-yl) ethynyl-4'-hydroxyazobenzene.

  The resulting 14.3 g of 4- (6-propyl-1,3-difluoronaphthalen-2-yl) ethynyl-4′-hydroxyazobenzene, 14.3 g of iodoethane, and 17.0 g of potassium carbonate were mixed in 76 mL of DMF. Stir at 12 ° C. for 12 hours. The mixture was cooled to room temperature, poured into 150 mL of ice water, and the collected precipitate was dissolved in a toluene-THF mixed solvent, washed with saturated brine, and dried over anhydrous sodium sulfate, and the solvent was distilled off under reduced pressure. Purification by column chromatography and recrystallization gave 4.2 g of 4- (6-propyl-1,3-difluoronaphthalen-2-yl) ethynyl-4'-ethoxyazobenzene.

Similarly, the following compounds were obtained.
4- (6-Propyl-1,3-difluoronaphthalen-2-yl) ethynyl-4'-propoxyazobenzene
4- (6-Ethyl-1,3-difluoronaphthalen-2-yl) ethynyl-4'-propoxyazobenzene
4- (6-Ethyl-1,3-difluoronaphthalen-2-yl) ethynyl-4′-ethoxyazobenzene (Example 3) 4- (6-propylnaphthalen-2-yl) ethynyl-4′-ethylazobenzene Manufacturing

  30 g of 6-propyl-2-naphthol and 20 g of pyridine were dissolved in 150 mL of dichloromethane, and 50.0 g of trifluoromethanesulfonic anhydride was added dropwise thereto under ice cooling. The mixture was further stirred at room temperature for 5 hours, and 10% hydrochloric acid was added dropwise under ice-cooling until acidic. The organic layer was separated, washed successively with saturated aqueous sodium hydrogen carbonate and saturated brine, dried over anhydrous sodium sulfate, and the solvent was evaporated under reduced pressure. Purification by column chromatography gave 51.3 g of 6-propylnaphthalen-2-yl trifluoromethanesulfonate.

  Using the obtained 51.3 g of 6-propylnaphthalen-2-yl trifluoromethanesulfonate, in the same manner as in Example 1, after induction to 6-propyl-2-ethynylnaphthalene, 4- (6-propylnaphthalene) -2-yl) ethynyl-4′-ethylazobenzene was obtained.

MS m / z: 402 [M +]
Similarly, the following compounds were obtained.
4- (6-Propyl-naphthalen-2-yl) ethynyl-4'-propylazobenzene
4- (6-Ethyl-naphthalen-2-yl) ethynyl-4'-propylazobenzene
4- (6-Ethyl-naphthalen-2-yl) ethynyl-4′-ethylazobenzene (Example 4) Preparation of 4- (6-propylnaphthalen-2-yl) ethynyl-4′-ethoxyazobenzene

  4- (6-Propylnaphthalen-2-yl) ethynyl-4'-ethoxyazobenzene was obtained in the same manner as in Example 2 except that 6-propyl-2-ethynylnaphthalene obtained in Example 3 was used.

Similarly, the following compounds were obtained.
4- (6-Propyl-naphthalen-2-yl) ethynyl-4'-propoxyazobenzene
4- (6-Ethyl-naphthalen-2-yl) ethynyl-4'-propoxyazobenzene
4- (6-Ethyl-naphthalen-2-yl) ethynyl-4'-ethoxyazobenzene (Comparative Example 1) Preparation of 4- (4-pentylphenyl) ethynyl-4'-propoxyazobenzene

4- (4-pentylphenylethynyl) was used in the same manner as in Example 2 except that 4-pentyl-1-ethynylbenzene was used instead of 2-propyl-6-ethynyl-5,7-difluoronaphthalene and iodopropyl was used instead of iodoethane. ) -4'-propoxyazobenzene was obtained.
Example 5 Preparation of Liquid Crystal Composition-1
Host liquid crystal composition (H) having the following composition

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

Nematic phase upper limit temperature (T _N-I ): 77.9 ° C.
Refractive index anisotropy (Δn): 0.1024
A liquid crystal composition comprising 90% of the base liquid crystal (H) and 10% of 4- (6-propyl-1,3-difluoronaphthalen-2-yl) ethynyl-4′-ethylazobenzene obtained in Example 1 was prepared. Prepared.
Example 6 Preparation of Liquid Crystal Composition-2
A liquid crystal composition comprising 90% of the base liquid crystal (H) and 10% of 4- (6-propyl-1,3-difluoronaphthalen-2-yl) ethynyl-4′-ethoxyazobenzene obtained in Example 2 was prepared. did.
Example 7 Preparation of Liquid Crystal Composition-3
A liquid crystal composition comprising 90% of the base liquid crystal (H) and 10% of 4- (6-propylnaphthalen-2-yl) ethynyl-4′-ethylazobenzene obtained in Example 3 was prepared.
Example 8 Preparation of Liquid Crystal Composition-4
A liquid crystal composition comprising 90% of the base liquid crystal (H) and 10% of 4- (6-propylnaphthalen-2-yl) ethynyl-4′-ethoxyazobenzene obtained in Example 4 was prepared.
Comparative Example 2 Preparation of Liquid Crystal Composition-5
A liquid crystal composition comprising 90% of the base liquid crystal (H) and 10% of 4- (4-pentylphenylethynyl) -4′-propoxyazobenzene obtained in Comparative Example 1 was prepared.

The following table shows Δn of the liquid crystal compositions prepared in Examples 5 to 8 and Comparative Example 2 together with the base liquid crystal (H), and Δn of the compounds of Examples 1 to 4 and Comparative Example 1 obtained by extrapolation therefrom. Shown in In addition, _TN-I of each liquid crystal composition is shown in the same table.

As can be seen from the comparison with the comparative example, the compound of the present invention represented by the general formula (1) shows an extremely large Δn. In addition, although the liquid crystal compositions of Examples 5 to 8 contained 10% of the compound of the present invention, there was no precipitation even after one week, and the stable liquid crystal phase was retained. It can be seen that it has good compatibility. Further, it can be seen that _TN-I is high and shows excellent liquid crystallinity.

  Moreover, it turned out that the cholesteric liquid crystal display element produced using the liquid crystal composition of Examples 5-8 shows the outstanding display characteristic.

Claims (20)

General formula (1)

Wherein R ¹ and R ² are each independently a fluorine atom, a chlorine atom, a cyano group, an alkyl group having 1 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, or 1 to 12 carbon atoms. Or an alkenyloxy group having 2 to 12 carbon atoms, but R ¹ and R ² do not both represent a substituent selected from a fluorine atom, a chlorine atom and a cyano group. In addition, one or two or more hydrogen atoms in the alkoxy group and / or alkenyloxy group may be each independently substituted with a fluorine atom, and one or two or more —CH _{2 in} these groups may be substituted. -Each independently may be substituted with -O-, -CO-, -COO- or -OCO- so that two or more oxygen atoms are not continuously bonded, and one or non- 2 adjacent More -CH ₂ - may be substituted with -CH = CH- or -C≡C- ^{independently,} Z 1, ^{Z 2} and ^{Z 3} each independently represent a single bond, -OCH ₂ - _{, -CH 2 O -, - C} 2 H 4 -, - C 4 H 8 -, - COO -, - OCO -, - CH = CH -, - CF = CF -, - CF 2 O -, - OCF 2 -, -CF ₂ CF ₂ -or -C≡C-, wherein A ¹ , A ³ , A ⁴ , A ⁵ and A ⁶ are each independently 1,4-phenylene group, naphthalene-1,4-diyl A hydrogen atom in each of A ¹ , A ³ , A ⁴ , A ⁵ and A ⁶ may be independently substituted with a halogen atom, or A ¹ , A ^{2, a 3, a 4,} 1 nonadjacent in ^{a 5} and ^{a 6} or two or more -CH = are still at -N = It may be, ^{A 2} is the general formula (2)

(Wherein, X ¹ , X ² , X ³ , X ⁴ , X ⁵ and X ⁶ each independently represents a hydrogen atom or a halogen atom), and represents a naphthalene-2,6-diyl group represented by: m, n, and p each independently represent 0 or 1, but m + n + p represents 0-2. ) A compound represented by The compound according to claim 1, wherein one or more of X ¹ , X ² , X ³ , X ⁴ , X ⁵ and X ^{6 in} the general formula (1) is a halogen atom. The compound according to claim 1, wherein one or more of X ¹ , X ² , X ³ , X ⁴ , X ⁵ and X ^{6 in} the general formula (1) is a fluorine atom. The compound according to claim 1, wherein two or more of X ¹ , X ² , X ³ , X ⁴ , X ⁵ and X ^{6 in} the general formula (1) are fluorine atoms. The compound according to claim ¹ , wherein, in the general formula (1), two or more of X ¹ , X ³ , X ⁴ and X ⁶ are fluorine atoms. The compound according to claim 1, wherein in the general formula (1), X ³ and X ⁴ are fluorine atoms. In General Formula (1), R ¹ and R ² are each independently R ³ —Z ⁴ — (wherein R ³ represents an alkyl group having 1 to 12 carbon atoms or an alkenyl group having 2 to 12 carbon atoms. And one or more hydrogen atoms in the group may be independently substituted with fluorine atoms, and Z ⁴ represents —CH═CH— or —C≡C—. The compound of any one of 1-6. In General Formula (1), one of A ¹ , A ² , A ³ , A ⁴ , A ⁵ and A ^{6 present} is a naphthalene-2,6-diyl group represented by General Formula (2) The compound according to any one of claims 1 to 7, wherein the others are each independently unsubstituted or a 1,4-phenylene group optionally substituted by one or more fluorine atoms. In general formula (1), m, n, and p are 0, The compound of any one of Claims 1-8 . In General Formula (1), at least one of R ¹ and R ² is an alkyl group having 1 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or 2 carbon atoms. 12 alkenyloxy group, or ^R 3 -Z ⁴ -, compound according to any one of claims 7-9. In General Formula (1), R ¹ and R ² are each independently an alkyl group having 1 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, and the number of carbon atoms. 2-12 alkenyloxy group, or ^R 3 -Z ⁴ -, compound according to any one of claims 7-9. In the general formula (1), compound according to any one of claims 1-10 either of R ¹ or R ² is a fluorine atom or a cyano group. A liquid crystal composition comprising one or more compounds represented by the general formula (1) according to any one of claims 1 to 12 . A liquid crystal display device using the liquid crystal composition according to claim 13 . A cholesteric liquid crystal display device using the liquid crystal composition according to claim 13 . General formula (3)

(Wherein R ¹ represents an alkyl group having 1 to 12 carbon atoms,
Z ¹ is a single bond, —OCH ₂ —, —CH ₂ O—, —C ₂ H ₄ —, —C ₄ H ₈ —, —COO—, —OCO—, —CH═CH—, —CF═CF—. _{, -CF 2 O -, - OCF} 2 -, - CF 2 CF 2 - or an -C≡C-, ^{a 1} is 1,4-phenylene group, a naphthalene-1,4-diyl group or a naphthalene-2,6 Represents a 6-diyl group, each hydrogen atom in A ¹ may be independently substituted with a halogen atom, and one or more non-adjacent —CH═ in A ¹ is —N═. X ¹ , X ² , X ³ , X ⁴ , X ⁵ and X ⁶ each independently represent a hydrogen atom or a halogen atom, and m represents 0 or 1. ) A compound represented by The compound according to claim 16 , wherein, in the general formula (3), two or more of X ¹ , X ² , X ³ , X ⁴ , X ⁵ and X ⁶ are fluorine atoms. The compound according to claim 16 , wherein, in the general formula (3), two or more of X ¹ , X ² , X ³ , X ⁴ , X ⁵ and X ⁶ are fluorine atoms. The compound according to claim 16 , wherein in the general formula (3), X ³ and X ⁴ are fluorine atoms. A compound represented by the general formula (3) according to any one of claims 16 to 19 is used, wherein the compound represented by the general formula (1) according to any one of claims 1 to 12 is used. A method for producing the represented compound.