Liquid crystal compound, and liquid crystal composition and element containing same

Abstract

The present invention provides a liquid crystal compound having a novel structure and exhibiting ferroelectricity.　Provided is a liquid crystal compound represented by formula (1-1) or formula (2-1).

Description

Liquid crystal compound, and liquid crystal composition and device containing the same

[0001] The present invention relates to a liquid crystal compound, and a liquid crystal composition and device containing the same.

[0002] 2. Description of the Related Art Conventionally, liquid crystal compounds have been used in applications such as liquid crystal displays because of their property of being oriented in a specific direction in the presence of an electric field, i.e., exhibiting dielectric anisotropy.

[0003] In recent years, it has been reported that liquid crystal compounds having a permanent dipole moment of a certain magnitude or more in a specific direction exhibit ferroelectricity, i.e., polarization even in the absence of an external electric field. Such ferroelectric liquid crystal compounds have properties such as a high relative dielectric constant and dielectric anisotropy, a hysteresis phenomenon in the relationship between the electric field and polarization, and a reversible reversal of polarization by changing the direction of the external electric field. For this reason, ferroelectric liquid crystal compounds can be suitably used in applications such as liquid crystal displays, optical devices, storage media, and sensors.

[0004] As a liquid crystal compound exhibiting such ferroelectricity, for example, Patent Document 1 discloses a compound DIO-3 represented by the following structure.

[0005] According to Patent Document 1, the compound DIO-3 exhibits a very large relative dielectric constant of about 10,000 at 1 Hz to 1 kHz in the temperature range of 48 to 66° C., for example.

[0006] JP 2017-145298 A

[0007] Although the compound described in Patent Document 1 exhibits a very high dielectric constant, it is not necessarily easy to synthesize. For example, the 1,3-dioxane ring contained in the compound described in Patent Document 1 is formed by reacting the corresponding aldehyde and 1,3-diol (acetalization reaction). However, these aldehydes and 1,3-diols are not inexpensive, which may limit the synthesis of analogs. Furthermore, of the geometric isomers (cis and trans isomers) obtained by the acetalization reaction, the trans isomer, which exhibits higher ferroelectricity, must be purified (by separating and removing the cis isomer), which may increase production costs. For this reason, there is a demand for liquid crystal compounds with novel structures that exhibit ferroelectricity.

[0008] Therefore, the present invention provides a liquid crystal compound or the like that exhibits ferroelectricity and has a novel structure.

[0009] The present invention is, for example, as follows.

[0010] [1] Formula (1-1) or Formula (2-1): (In the above formula, R １ represents hydrogen, a polymerizable group, or an alkyl group having 1 to 20 carbon atoms, and in this case, any —CH ２ - may be replaced by -O-, -S-, -COO-, -OCO-, -CH=CH-, -CF=CF-, or -C≡C-, and any hydrogen in the alkyl may be replaced by a halogen; X is hydrogen, a polymerizable group, a halogen, -CN, or -NO ２ , -NCO, -NCS, -CH ２ F, -CHF ２ , -CF ３ , -OCH ２ F, -OCHF ２ , -OCF ３ , alkyl having 1 to 3 carbon atoms, in which any —CH ２ - may be replaced by -O-, -S-, -COO-, -OCO-, -CH=CH-, -CF=CF-, or -C≡C-; any hydrogen in the alkyl may be replaced by halogen; ３ may be replaced by —CN, Ar １ , Ar ２ , Ar３ , Ar ４ , and Ar ５ are each independently substituted or unsubstituted arylene, substituted or unsubstituted heteroarylene, １ , A ２ , and A ３ are each independently a single bond or alkylene having 1 to 8 carbon atoms, and any —CH ２ - may be replaced by -O-, -S-, -COO-, -OCO-, -CSO-, -OCS-, -N=N-, -CH=N-, -N=CH-, -N(O)=N-, -N=N(O)-, -CH=CH-, -CF=CF-, or -C≡C-, any hydrogen in the alkylene may be replaced by a halogen, and n and m are each independently 0 or 1. [2] A liquid crystal compound represented by the following formula (1-2) or (2-2): (In the above formula, R １ represents hydrogen, a polymerizable group, or an alkyl group having 1 to 20 carbon atoms, and in this case, any —CH ２ - may be replaced by -O-, -S-, -COO-, -OCO-, -CH=CH-, -CF=CF-, or -C≡C-, and any hydrogen in the alkyl may be replaced by a halogen; R ２ each independently represents a polymerizable group, a halogen, —CN, or —NO ２ , -NCO, -NCS, -CH ２ F, -CHF ２ , -CF ３ , -OCH ２ F, -OCHF ２ , -OCF ３ , alkyl having 1 to 3 carbon atoms, in which any —CH ２ - may be replaced by -O-, -S-, -COO-, -OCO-, -CH=CH-, -CF=CF-, or -C≡C-; any hydrogen in the alkyl may be replaced by halogen; ３ may be replaced by —CN, and X is hydrogen, a polymerizable group, a halogen, —CN, or —NO ２ , -NCO, -NCS, -CH ２ F, -CHF２ , -CF ３ , -OCH ２ F, -OCHF ２ , -OCF ３ , alkyl having 1 to 3 carbon atoms, in which any —CH ２ - may be replaced by -O-, -S-, -COO-, -OCO-, -CH=CH-, -CF=CF-, or -C≡C-; any hydrogen in the alkyl may be replaced by halogen; ３ may be replaced by -CN, ３ represents a single bond, an alkylene having 1 to 8 carbon atoms, and any —CH ２ - may be replaced by -O-, -S-, -COO-, -OCO-, -CSO-, -OCS-, -N=N-, -CH=N-, -N=CH-, -N(O)=N-, -N=N(O)-, -CH=CH-, -CF=CF-, or -C≡C-, any hydrogen in the alkylene may be replaced by a halogen, and each p is independently an integer of 0 to 4. [3] The liquid crystal compound according to the above item [1], represented by the following formulae (1-3) to (2-4): (In the above formula, R １ represents hydrogen, a polymerizable group, or an alkyl group having 1 to 20 carbon atoms, and in this case, any —CH ２ - may be replaced by -O-, -S-, -COO-, -OCO-, -CH=CH-, -CF=CF-, or -C≡C-, and any hydrogen in the alkyl may be replaced by a halogen; R ３ are each independently hydrogen, a polymerizable group, a halogen, —CN, or —NO ２ , -NCO, -NCS, -CH ２ F, -CHF ２ , -CF ３ , -OCH ２ F, -OCHF ２ , -OCF ３ , alkyl having 1 to 3 carbon atoms, in which any —CH ２- may be replaced by -O-, -S-, -COO-, -OCO-, -CH=CH-, -CF=CF-, or -C≡C-; any hydrogen in the alkyl may be replaced by halogen; ３ may be replaced by —CN, and X is hydrogen, a polymerizable group, a halogen, —CN, or —NO ２ , -NCO, -NCS, -CH ２ F, -CHF ２ , -CF ３ , -OCH ２ F, -OCHF ２ , -OCF ３ , alkyl having 1 to 3 carbon atoms, in which any —CH ２ - may be replaced by -O-, -S-, -COO-, -OCO-, -CH=CH-, -CF=CF-, or -C≡C-; any hydrogen in the alkyl may be replaced by halogen; ３ [4] The liquid crystal compound according to the above [1], represented by the following formulae (1) to (13): The liquid crystal compound according to [1] above, represented by the formula: [5] The liquid crystal compound according to any one of [1] to [4] above, having a dielectric constant of 1000 or more. [6] The liquid crystal compound according to any one of [1] to [5] above, having a dipole moment of 8.5 D or less. [7] A liquid crystal composition comprising the liquid crystal compound according to any one of [1] to [6] above. [8] A liquid crystal composition comprising two or more liquid crystal compounds according to any one of [1] to [6] above. [9] The liquid crystal composition according to [7] above, further comprising a liquid crystal compound with a dielectric constant of less than 1000.

[10] The liquid crystal composition according to [8] above, further comprising a liquid crystal compound with a dielectric constant of less than 1000.

[11] A device comprising the liquid crystal compound according to any one of [1] to [6] above or the liquid crystal composition according to any one of [7] to

[10] above.

[12] The device according to

[11] above, further comprising a voltage application unit.

[0011] The present invention provides a liquid crystal compound having a novel structure and exhibiting ferroelectricity, which can have at least one of the following effects: various analogs can be synthesized inexpensively, the compound can be produced in high yield, the compound exhibits a high dielectric constant, the compound exhibits hysteresis in the relationship between the electric field and polarization, and the compound exhibits reversible polarization reversal by changing the direction of an external electric field.

[0012] 1A is a polarized light microscope (POM) image of the A phase of the liquid crystal compounds of Examples 1 to 4 measured using a non-alignment treated cell. Ｆ FIG. 1B shows the ferroelectric nematic phase (N Ｆ phase). FIG. 1C shows the ferroelectric nematic phase (N Ｆ phase). FIG. 1D shows the ferroelectric smectic phase (Sm Ｆ FIG. 2A shows the electric flux density-electric field (D-E) curves of the liquid crystal compounds of Examples 1 to 4. FIG. 2A shows the D-E curve (frequency: 100 Hz) of the liquid crystal compound of Example 1. FIG. 2B shows the D-E curve (frequency: 200 Hz) of the liquid crystal compound of Example 2. FIG. 2C shows the D-E curve (frequency: 100 Hz) of the liquid crystal compound of Example 3. FIG. 2D shows the D-E curve (frequency: 10 Hz) of the liquid crystal compound of Example 4. FIG. 2B shows the D-E curve (frequency: 10 Hz) of the liquid crystal compound of Example 4. FIG. 2C shows the D-E curve (frequency: 100 Hz) of the liquid crystal compound of Example 3. FIG. 2D shows the D-E curve (frequency: 10 Hz) of the liquid crystal compound of Example 4. FIG. 4A shows the change in the phase transition temperature of the liquid crystal compositions of Examples 14 to 19. FIG. 4A shows the data of Examples 2, 14 to 16, and 3 (horizontal axis: content of the liquid crystal compound of Example 3, vertical axis: phase transition temperature). FIG. 4B shows the data of Examples 15, 17 to 19, and Comparative Example 5 (horizontal axis: content of the liquid crystal compound of Compound A, vertical axis: phase transition temperature).

[0013] Hereinafter, embodiments of the present invention will be described in detail.

[0014] 1. Liquid Crystal Compound The liquid crystal compound according to the present invention is represented by the following formula (1-1) or formula (2-1).

[0015]

[0016] In the above formula, R １is hydrogen, a polymerizable group, or an alkyl having 1 to 20 carbon atoms. ２ - may be replaced by -O-, -S-, -COO-, -OCO-, -CH=CH-, -CF=CF-, or -C≡C-. Any hydrogen in the alkyl may be replaced by halogen.

[0017] Examples of the polymerizable group include functional groups containing an acrylic group, a methacrylic group, a vinyloxy group, an isocyanate group, an isothiocyanate group, an epoxy group, an aziridine group, an azlactone group, a chloro-s-triazine group, or a β-chloroethylaminosulfonyl group. The polymerizable group is represented, for example, by any one of the following formulas (3-1) to (3-10).

[0018] In the above formula, L may be a single bond, methylene, ethylene, propylene, isopropylene, butylene, pentylene, hexylene, heptylene, 2-ethylhexylene, -O-, -S-, etc. Furthermore, "*" represents a link to the carbon atom of the carbonyl group in formula (1-1), and a link to the oxygen atom in formula (2-1).

[0019] Examples of the alkyl having 1 to 20 carbon atoms include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, pentyl, hexyl, heptyl, octyl, 2-ethylhexyl, nonyl, and decyl.

[0020] Any —CH in alkyl ２Examples of the alkyl having 1 to 20 carbon atoms when - is replaced by -O-, -S-, -COO-, -OCO-, -CH=CH-, -CF=CF-, or -C≡C- include -O-; -S-; -COO-; -OCO-; -CH=CH-; -CF=CF-; -C≡C-; alkoxy having 1 to 20 carbon atoms such as methoxy, ethoxy, propyloxy, butyloxy, and tert-butyloxy; alkoxyalkyl having 1 to 20 carbon atoms such as methoxymethyl, methoxyethyl, methoxypropyl, ethoxymethyl, ethoxyethyl, and ethoxypropyl; methylthio, ethylthio, propylthio, isopropylthio, butylthio, and tert- alkylthio having 1 to 20 carbon atoms such as butylthio; alkylthio having 1 to 20 carbon atoms such as methylthiomethyl, methylthioethyl, ethylthiomethyl, and ethylthioethyl; alkylcarbonyloxy having 1 to 20 carbon atoms such as methylcarbonyloxy and ethylcarbonyloxy; alkoxycarbonyl having 1 to 20 carbon atoms such as methoxycarbonyl and ethoxycarbonyl; alkenyl having 1 to 20 carbon atoms such as vinyl, 1-propenyl, 2-propenyl, 2-butenyl, and 3-butenyl; difluoroalkenyl having 1 to 20 carbon atoms such as 1,2-difluorovinyl; and alkynyl having 1 to 20 carbon atoms such as methylidyne and propargyl.

[0021] Examples of the alkyl having 1 to 20 carbon atoms in which any hydrogen atom in the alkyl has been replaced by a halogen include fluoromethyl, difluoromethyl, trifluoromethyl, chloromethyl, dichloromethyl, and bromomethyl.

[0022] Of these, R １ is preferably hydrogen, alkyl having 1 to 20 carbon atoms, or alkenyl having 1 to 20 carbon atoms, more preferably alkyl having 1 to 10 carbon atoms, or alkenyl having 1 to 10 carbon atoms, even more preferably alkyl having 1 to 5 carbon atoms, or alkenyl having 1 to 5 carbon atoms, particularly preferably alkyl having 1 to 3 carbon atoms, or alkenyl having 1 to 3 carbon atoms, very preferably alkyl having 1 to 3 carbon atoms, and most preferably propyl.

[0023] X is hydrogen, a polymerizable group, a halogen, —CN, or —NO ２, -NCO, -NCS, -CH ２ F, -CHF ２ , -CF ３ , -OCH ２ F, -OCHF ２ , -OCF ３ , alkyl having 1 to 3 carbon atoms. In this case, any —CH ２ - may be replaced by -O-, -S-, -COO-, -OCO-, -CH=CH-, -CF=CF-, or -C≡C-. Any hydrogen in the alkyl may be replaced by a halogen. Furthermore, -CH ３ may be replaced by -CN.

[0024] The polymerizable group is R １ Specifically, they are represented by the above formulas (3-1) to (3-10).

[0025] Examples of halogen include fluorine, chlorine, bromine, and iodine.

[0026] Examples of the alkyl having 1 to 3 carbon atoms include methyl, ethyl, propyl, and isopropyl.

[0027] Any —CH in alkyl ２ Examples of the alkyl having 1 to 3 carbon atoms in which - is replaced by -O-, -S-, -COO-, -OCO-, -CH=CH-, -CF=CF-, or -C≡C- include alkoxy having 1 to 3 carbon atoms such as methoxy, ethoxy, and propyloxy; alkoxyalkyl having 1 to 3 carbon atoms such as methoxymethyl, methoxyethyl, and ethoxymethyl; alkylthio having 1 to 3 carbon atoms such as methylthio, ethylthio, propylthio, and isopropylthio; methylthiomethyl, methylthioethyl, and ethyl alkylcarbonyloxy having 1 to 3 carbon atoms such as methylcarbonyloxy and ethylcarbonyloxy; alkoxycarbonyl having 1 to 3 carbon atoms such as methoxycarbonyl and ethoxycarbonyl; alkenyl having 1 to 20 carbon atoms such as vinyl, 1-propenyl and 2-propenyl; difluoroalkenyl having 1 to 3 carbon atoms such as 1,2-difluorovinyl; and alkynyl having 1 to 3 carbon atoms such as methylidyne and propargyl.

[0028] Examples of the alkyl having 1 to 3 carbon atoms in which any hydrogen atom in the alkyl has been replaced by a halogen atom include fluoromethyl, difluoromethyl, trifluoromethyl, chloromethyl, dichloromethyl, and bromomethyl.

[0029] -CH in alkyl ３ Examples of the alkyl having 1 to 3 carbon atoms in which the alkyl group is replaced by —CN include cyanomethyl and cyanoethyl.

[0030] Among these, X is a halogen, —CN, or —NO ２ , -NCO, -NCS, -CF ３ , -OCF ３ is preferably fluorine, —CN, —NO ２ , -CF ３ , and more preferably fluorine, —CN, —NO ２ In one embodiment, X is fluorine. In another embodiment, X is —CN. In another embodiment, X is —NO ２ is.

[0031] Ar １ , Ar ２ , Ar ３ , Ar ４ , and Ar ５ are each independently substituted or unsubstituted arylene, or substituted or unsubstituted heteroarylene.

[0032] Examples of arylene include divalent groups derived from phenyl, naphthyl, and anthracenyl.

[0033] Examples of heteroarylene include divalent groups derived from furan, pyrrole, imidazole, pyrazole, oxazole, isoxazole, thiazole, triazole, pyridine, pyrimidine, pyridazine, pyrazine, indole, quinoline, isoquinoline, naphthyridine, phthalazine, quinoxaline, quinazoline, benzoxazole, benzothiazole, and carbazole.

[0034] Substituents that the arylene and heteroarylene may have include hydrogen, a polymerizable group, halogen, —CN, and —NO. ２ , -NCO, -NCS, -CH ２ F, -CHF ２ , -CF ３ , -OCH ２ F, -OCHF ２ , -OCF ３ , alkyl having 1 to 3 carbon atoms. In this case, any —CH ２ - may be replaced by -O-, -S-, -COO-, -OCO-, -CH=CH-, -CF=CF-, or -C≡C-. Any hydrogen in the alkyl may be replaced by a halogen. Furthermore, -CH ３ may be replaced by -CN.

[0035] Specific examples of the substituent that the arylene and heteroarylene may have are the same as those described above for X.

[0036] Among these, Ar １ , Ar ２ , Ar ３ , Ar ４ , and Ar ５ are each independently preferably a substituted or unsubstituted phenylene, more preferably a substituted or unsubstituted phenylene, and even more preferably represented by any one of the following formulas (4-1) to (4-10). １ ~A ５ , or the linkage with X.

[0037]

[0038] In one embodiment, Ar １ is preferably a group represented by formula (4-1). ２ is preferably a group represented by formula (4-1). ３ is preferably a group represented by formula (4-1) or formula (4-5). ４is preferably a group represented by formula (4-2) or formula (4-5). ５ is preferably a group represented by formula (4-5).

[0039] In one preferred embodiment, Ar ３ is a group represented by formula (4-1), and Ar ４ is a group represented by formula (4-2) or formula (4-5), and Ar ５ is preferably a group represented by formula (4-5), and Ar ３ is a group represented by formula (4-1), and Ar ４ is a group represented by formula (4-2), and Ar ５ is more preferably a group represented by formula (4-5). ３ is a group represented by formula (4-5), and Ar ４ is a group represented by formula (4-2) or formula (4-5), and Ar ５ is preferably a group represented by formula (4-5), and Ar ３ is a group represented by formula (4-5), and Ar ４ is a group represented by formula (4-2), and Ar ５ is a group represented by formula (4-5), or Ar ３ is a group represented by formula (4-5), and Ar ４ is a group represented by formula (4-5), and Ar ５ is more preferably a group represented by formula (4-5).

[0040] A １ , A ２ , and A ３ are each independently a single bond or alkylene having 1 to 8 carbon atoms. In this case, any —CH ２ - may be replaced by -O-, -S-, -COO-, -OCO-, -CSO-, -OCS-, -N=N-, -CH=N-, -N=CH-, -N(O)=N-, -N=N(O)-, -CH=CH-, -CF=CF- or -C≡C-. Furthermore, any hydrogen in the alkylene may be replaced by a halogen.

[0041] Examples of the alkylene having 1 to 8 carbon atoms include methylene, ethylene, propylene, isopropylene, butylene, pentylene, hexylene, heptylene, and 2-ethylhexylene.

[0042] Any —CH in alkylene ２ Examples of alkylene having 1 to 8 carbon atoms in which - is replaced by -O-, -S-, -COO-, -OCO-, -CSO-, -OCS-, -N=N-, -CH=N-, -N=CH-, -N(O)=N-, -N=N(O)-, -CH=CH-, -CF=CF-, or -C≡C- include -O-, -S-, -COO-, -OCO-, -CSO-, -OCS-, -N=N-, -CH=N-, -N=CH-, -N(O)=N-, -N=N(O)-, -CH=CH-, -CF=CF-, -C≡C-, and -CH ２ —O—, —CH ２ CH ２ —O—, —CH ２ CH ２ CH ２ —O—, —CH ２ -O-CH ２ -, -CH ２ CH ２ -O-CH ２ -, -CH ２ CH ２ -O-CH ２ CH ２ -, -CH ２ -S-, -CH ２ CH ２ -S-, -CH ２ CH ２ CH ２ -S-, -CH ２ -S-CH ２ -, -CH ２ CH ２ -S-CH ２ -, -CH ２ CH ２ -S-CH ２ CH ２ -, -CH ２ -COO-, -CH ２ CH ２ -COO-, -CH ２ —OCO—, —CH ２ CH ２ -OCO- and the like.

[0043] Of these, A １ , A ２ , and A ３ are each independently preferably a single bond, —O—, —COO—, or —OCO—, more preferably a single bond, —COO—, or —OCO—, and further preferably a single bond or —COO—. ３ is preferably a single bond, —O—, —COO—, or —OCO—, more preferably a single bond, —COO—, or —OCO—, further preferably a single bond or —COO—, and particularly preferably —COO—.

[0044] n and m each independently represent 0 or 1, and preferably 0.

[0045] Among the above, the compound represented by formula (1-1) is preferred from the viewpoint of further improving the dielectric properties.

[0046] The liquid crystal compound according to the present invention is preferably represented by the following formula (1-2) or formula (2-2).

[0047] In the above formula, R １ is hydrogen, a polymerizable group, or an alkyl having 1 to 20 carbon atoms. ２ - may be replaced by -O-, -S-, -COO-, -OCO-, -CH=CH-, -CF=CF-, or -C≡C-. Any hydrogen in the alkyl may be replaced by a halogen.

[0048] R １ is the same as that described above in formula (1-1) and formula (2-1).

[0049] Of these, R １is preferably hydrogen, alkyl having 1 to 20 carbon atoms, or alkenyl having 1 to 20 carbon atoms, more preferably alkyl having 1 to 10 carbon atoms, or alkenyl having 1 to 10 carbon atoms, even more preferably alkyl having 1 to 5 carbon atoms, or alkenyl having 1 to 5 carbon atoms, particularly preferably alkyl having 1 to 3 carbon atoms, or alkenyl having 1 to 3 carbon atoms, very preferably alkyl having 1 to 3 carbon atoms, and most preferably propyl.

[0050] R ２ each independently represents a polymerizable group, a halogen, —CN, or —NO ２ , -NCO, -NCS, -CH ２ F, -CHF ２ , -CF ３ , -OCH ２ F, -OCHF ２ , -OCF ３ , alkyl having 1 to 3 carbon atoms. In this case, any —CH ２ - may be replaced by -O-, -S-, -COO-, -OCO-, -CH=CH-, -CF=CF-, or -C≡C-. Any hydrogen in the alkyl may be replaced by a halogen. Furthermore, -CH ３ may be replaced by -CN.

[0051] R ２ is the same as those described as the substituents that the arylene and heteroarylene may have in formula (1-1) and formula (2-1) (that is, those described as X).

[0052] Of these, R ２ is halogen, -CN, -NO ２ , -NCO, -NCS, -CF ３ , -OCF ３ is preferably fluorine, —CN, —NO ２ , -CF ３ , and more preferably fluorine, —CN, —NO ２ In one embodiment, R ２ is fluorine. Also, in one embodiment, R ２is —CN. Also, in one embodiment, R ２ Ha-NO ２ is.

[0053] X is hydrogen, a polymerizable group, a halogen, —CN, or —NO ２ , -NCO, -NCS, -CH ２ F, -CHF ２ , -CF ３ , -OCH ２ F, -OCHF ２ , -OCF ３ , alkyl having 1 to 3 carbon atoms. In this case, any —CH ２ - may be replaced by -O-, -S-, -COO-, -OCO-, -CH=CH-, -CF=CF-, or -C≡C-. Any hydrogen in the alkyl may be replaced by a halogen. Furthermore, -CH ３ may be replaced by -CN.

[0054] X is the same as that described as X in formula (1-1) and formula (2-1).

[0055] Among these, X is halogen, —CN, —NO ２ , -NCO, -NCS, -CF ３ , -OCF ３ is preferably fluorine, —CN, —NO ２ , -CF ３ , and more preferably fluorine, —CN, —NO ２ In one embodiment, X is fluorine. In another embodiment, X is —CN. In another embodiment, X is —NO ２ is.

[0056] A ３ is a single bond or alkylene having 1 to 8 carbon atoms. In this case, any —CH ２- may be replaced by -O-, -S-, -COO-, -OCO-, -CSO-, -OCS-, -N=N-, -CH=N-, -N=CH-, -N(O)=N-, -N=N(O)-, -CH=CH-, -CF=CF- or -C≡C-. Furthermore, any hydrogen in the alkylene may be replaced by a halogen.

[0057] A ３ In formula (1-1) and formula (2-1), A ３ It is similar to that described as

[0058] Of these, A ３ is preferably a single bond, —O—, —COO—, or —OCO—, more preferably a single bond, —COO—, or —OCO—, further preferably a single bond or —COO—, and particularly preferably —COO—.

[0059] Each p is independently an integer of 0 to 4, preferably an integer of 0 to 2.

[0060] Among the above, the compound represented by formula (1-2) is preferred from the viewpoint of further improving the dielectric properties.

[0061] The liquid crystal compound according to the present invention is more preferably a compound represented by the following formulas (1-3) to (2-4).

[0062] In the above formula, R １ is hydrogen, a polymerizable group, or an alkyl having 1 to 20 carbon atoms. ２ - may be replaced by -O-, -S-, -COO-, -OCO-, -CH=CH-, -CF=CF-, or -C≡C-. Any hydrogen in the alkyl may be replaced by halogen.

[0063] R １ is the same as that described above in formula (1-1) and formula (2-1).

[0064] Of these, R １is preferably hydrogen, alkyl having 1 to 20 carbon atoms, or alkenyl having 1 to 20 carbon atoms, more preferably alkyl having 1 to 10 carbon atoms, or alkenyl having 1 to 10 carbon atoms, even more preferably alkyl having 1 to 5 carbon atoms, or alkenyl having 1 to 5 carbon atoms, particularly preferably alkyl having 1 to 3 carbon atoms, or alkenyl having 1 to 3 carbon atoms, very preferably alkyl having 1 to 3 carbon atoms, and most preferably propyl.

[0065] R ３ are each independently hydrogen, a polymerizable group, a halogen, —CN, or —NO ２ , -NCO, -NCS, -CH ２ F, -CHF ２ , -CF ３ , -OCH ２ F, -OCHF ２ , -OCF ３ , alkyl having 1 to 3 carbon atoms. In this case, any —CH ２ - may be replaced by -O-, -S-, -COO-, -OCO-, -CH=CH-, -CF=CF-, or -C≡C-. Any hydrogen in the alkyl may be replaced by a halogen. Furthermore, -CH ３ may be replaced by -CN.

[0066] R ３ is the same as those described as the substituents that the arylene and heteroarylene may have in formula (1-1) and formula (2-1) (i.e., those described as X) except for hydrogen.

[0067] Of these, R ３ is halogen, -CN, -NO ２ , -NCO, -NCS, -CF ３ , -OCF ３ is preferably fluorine, —CN, —NO ２ , -CF ３ , and more preferably fluorine, —CN, —NO ２ In one embodiment, R ３ is hydrogen. Also, in one embodiment, R ３is fluorine. Also, in one embodiment, R ３ is —CN. Also, in one embodiment, R ３ Ha-NO ２ is.

[0068] X is hydrogen, a polymerizable group, a halogen, —CN, or —NO ２ , -NCO, -NCS, -CH ２ F, -CHF ２ , -CF ３ , -OCH ２ F, -OCHF ２ , -OCF ３ , alkyl having 1 to 3 carbon atoms. In this case, any —CH ２ - may be replaced by -O-, -S-, -COO-, -OCO-, -CH=CH-, -CF=CF-, or -C≡C-. Any hydrogen in the alkyl may be replaced by a halogen. Any hydrogen in the alkyl may be replaced by a halogen. Furthermore, -CH ３ may be replaced by -CN.

[0069] X is the same as that described as X in formula (1-1) and formula (2-1).

[0070] Among these, X is halogen, —CN, —NO ２ , -NCO, -NCS, -CF ３ , -OCF ３ is preferably fluorine, —CN, —NO ２ , -CF ３ , and more preferably fluorine, —CN, —NO ２ In one embodiment, X is fluorine. In another embodiment, X is —CN. In another embodiment, X is —NO ２ is.

[0071] Among the above, the compound represented by formula (1-3) is preferred from the viewpoint of further improving the dielectric properties.

[0072] The liquid crystal compound according to the present invention is more preferably a compound represented by the following formulas (1-5) to (2-6).

[0073] In the above formula, R １ and X are the same as those described in the above formulas (1-3) to (2-4).

[0074] R ４ each independently represents a polymerizable group, a halogen, —CN, or —NO ２ , -NCO, -NCS, -CH ２ F, -CHF ２ , -CF ３ , -OCH ２ F, -OCHF ２ , -OCF ３ , alkyl having 1 to 3 carbon atoms. In this case, any —CH ２ - may be replaced by -O-, -S-, -COO-, -OCO-, -CH=CH-, -CF=CF-, or -C≡C-. Any hydrogen in the alkyl may be replaced by a halogen. Furthermore, -CH ３ may be replaced by -CN.

[0075] R ４ is the same as those described as the substituents that the arylene and heteroarylene may have in formula (1-1) and formula (2-1) (that is, those described as X).

[0076] Of these, R ４ is halogen, -CN, -NO ２ , -NCO, -NCS, -CF ３ , -OCF ３ is preferably fluorine, —CN, —NO ２ , -CF ３ , and more preferably fluorine, —CN, —NO ２ In one embodiment, R ３ is fluorine. Also, in one embodiment, R ３ is —CN. Also, in one embodiment, R ３ Ha-NO ２ is.

[0077] Among the above, from the viewpoint of further improving the dielectric properties, the compound represented by formula (1-5) or formula (1-6) is preferred. In one embodiment, the liquid crystal compound according to the present invention is preferably a compound represented by formula (1-5). Also, in one embodiment, the liquid crystal compound according to the present invention is preferably a compound represented by formula (1-6).

[0078] In one embodiment, the liquid crystal compound according to the present invention is represented by any one of the following formulas (1) to (13).

[0079] Of these, the liquid crystal compound is more preferably a compound represented by the following formulas (1) to (4).

[0080] The liquid crystal compound according to the present invention exhibits a ferroelectric nematic phase (N Ｆ phase), nematic phase (N phase), ferroelectric smectic phase (Sm Ｆ In this case, the ferroelectric smectic phase (Sm Ｆ phase) is a ferroelectric smectic A phase (SmA Ｆ phase), ferroelectric smectic C phase (SmC Ｆ The smectic phase (Sm phase) may be a smectic A phase (SmA phase) or a smectic C phase (SmC phase). In this specification, "ferroelectric" means that the material exhibits a hysteresis phenomenon in the relationship between the electric field and polarization. Specifically, it means that the material exhibits hysteresis in the electric flux density-electric field (D-E) curve obtained from polarization reversal current measurement. In this case, the polarization reversal current measurement is carried out by the method described in the Examples.

[0081] In a preferred embodiment, the liquid crystal compound according to the present invention exhibits a ferroelectric nematic phase (N Ｆ In a preferred embodiment, the liquid crystal compound according to the present invention exhibits a ferroelectric smectic phase (Sm Ｆ phase).

[0082] The dielectric constant of the liquid crystal compound according to the present invention is preferably 100 or more, more preferably 500 or more, further preferably 1000 or more, and particularly preferably 10000 or more. In this specification, the dielectric constant of the liquid crystal compound refers to the dielectric constant of the liquid crystal compound when the liquid crystal compound is in a ferroelectric nematic phase (N Ｆ The dielectric constant is the highest value among the dielectric constants at the temperatures at which the polymer is in the liquid crystal phase (phase) or nematic phase (N phase). The dielectric constant is measured by the method described in the examples.

[0083] The dipole moment of the liquid crystal compound according to the present invention is preferably 12D or less, more preferably 10D or less, even more preferably 8.5D or less, particularly preferably 4 to 8.5D, and most preferably 4 to 7.5D, 4 to 7D, 5 to 7D, 6 to 7D, 7 to 8.5D, 7.2 to 8.5D, 7.5 to 8.5D, 7.2 to 8D, or 7.5 to 8D. Despite their low dipole moment, the liquid crystal compounds according to the present invention can exhibit high dielectric properties (e.g., relative dielectric constants of 100 or more, 1,000 or more, or 10,000 or more). In this specification, the dipole moment of the liquid crystal compound is measured by the method described in the Examples.

[0084] Since the liquid crystal compound of the present invention does not contain a 1,3-dioxane ring, it can be produced without using expensive raw materials, facilitating the synthesis of analogues. Furthermore, since geometric isomers (cis and trans isomers) based on the 1,3-dioxane ring are not produced, the liquid crystal compound can be produced in high yield, resulting in excellent production costs.

[0085] 2. Liquid Crystal Composition According to one aspect of the present invention, a liquid phase composition is provided. The liquid crystal composition includes the liquid crystal compound according to the present invention described above. In this specification, the term "liquid crystal composition" includes two or more liquid crystal compounds. By mixing two or more liquid crystal compounds, it may be possible to widen the operating temperature range, optimize physical properties (optical properties, viscosity, dielectric properties, etc.), improve response speed, improve stability, reduce manufacturing costs, and so on.

[0086] [Liquid Crystal Compound] The liquid crystal composition contains two or more liquid crystal compounds. In one embodiment, the liquid crystal composition contains two or more of the liquid crystal compounds according to the present invention described above.

[0087] In a preferred embodiment, the liquid crystal composition can be used in a combination of a compound represented by formula (1) and a compound represented by formula (2), a combination of a compound represented by formula (1) and a compound represented by formula (3), a combination of a compound represented by formula (1) and a compound represented by formula (4), a combination of a compound represented by formula (2) and a compound represented by formula (3), a combination of a compound represented by formula (2) and a compound represented by formula (4), a combination of a compound represented by formula (3) and a compound represented by formula (4), a combination of a compound represented by formula (1), a compound represented by formula (2), and a compound represented by formula (3), a combination of a compound represented by formula (1), a compound represented by formula (2), and a compound represented by formula (4), a combination of a compound represented by formula (1), a compound represented by formula (3), and a compound represented by formula (4), a combination of a compound represented by formula (2), a compound represented by formula (3), and a compound represented by formula (4), a combination of a compound represented by formula (2), a compound represented by formula (3), and a compound represented by formula (4), and a combination of a compound represented by formula (1), a compound represented by formula (2), a compound represented by formula (3), and a compound represented by formula (4).

[0088] The content of the liquid crystal compound according to the present invention is preferably 5 to 100% by mass, 10 to 100% by mass, 20 to 100% by mass, 30 to 100% by mass, or 40 to 100% by mass, and more preferably 50 to 100% by mass, relative to the total mass of the liquid crystal composition. The liquid crystal composition may consist of two or more liquid crystal compounds according to the present invention (100% by mass). In one embodiment, the content of the liquid crystal compound according to the present invention is preferably 60 to 100% by mass, 70 to 100% by mass, or 80 to 100% by mass, more preferably 90 to 100% by mass, even more preferably 95 to 100% by mass, and most preferably 100% by mass, relative to the total mass of the liquid crystal composition. When the content of the liquid crystal compound according to the present invention is within the above range, high dielectric properties can be obtained. In one embodiment, the content of the liquid crystal compound according to the present invention is preferably 40 to 80% by mass, more preferably 40 to 75% by mass, 40 to 65% by mass, 50 to 75% by mass, or 50 to 65% by mass, and even more preferably 40 to 65% by mass, relative to the total mass of the liquid crystal composition. When the content of the liquid crystal compound according to the present invention is in the above range, a wider operating temperature range can be achieved.

[0089] The liquid crystal composition may contain one or more liquid crystal compounds according to the present invention as described above, as well as other liquid crystal compounds.

[0090] The other liquid crystal compound is a liquid crystal compound other than the liquid crystal compound according to the present invention, and is preferably a liquid crystal compound having a relative dielectric constant of less than 1000. That is, in one embodiment, the liquid crystal composition contains one or more liquid crystal compounds according to the present invention and a liquid crystal compound having a relative dielectric constant of less than 1000. In one embodiment, the liquid crystal composition contains one liquid crystal compound according to the present invention and a liquid crystal compound having a relative dielectric constant of less than 1000. In another embodiment, the liquid crystal compound contains two or more liquid crystal compounds according to the present invention and a liquid crystal compound having a relative dielectric constant of less than 1000.

[0091] Liquid crystal compounds having a relative dielectric constant of less than 1000 are not particularly limited, but include compounds represented by the following formula (5-1) or formula (6-1). Since the compound has one less phenylene group than the compound represented by formula (1-2) or formula (2-2), the rigidity of the compound is relatively reduced, and the dielectric constant can be less than 1000.

[0092] In the above formula, R １ , R ２ , A ３ , X, and p are the same as those described in the above formula (1-2) or formula (2-2).

[0093] The liquid crystal compound having a relative dielectric constant of less than 1000 is preferably represented by the following formulas (5-2) to (6-3).

[0094] In the above formula, R １ , R ３ and X are the same as those described in the above formulas (1-3) to (2-4).

[0095] Specific examples of liquid crystal compounds having a relative dielectric constant of less than 1000 include compounds represented by the following formulae (A) to (F).

[0096]

[0097] The content of the liquid crystal compound having a relative dielectric constant of less than 1000 is preferably 60% by mass or less, relative to the total mass of the liquid crystal composition. In one embodiment, the content of the liquid crystal compound having a relative dielectric constant of less than 1000 is preferably 20% by mass or less, more preferably 10% by mass or less, and even more preferably 5% by mass or less, relative to the total mass of the liquid crystal composition. When the content of the liquid crystal compound having a relative dielectric constant of less than 1000 is 20% by mass or less, high dielectric properties can be obtained. In one embodiment, the content of the liquid crystal compound having a relative dielectric constant of less than 1000 is preferably 20 to 60% by mass, more preferably 25 to 60% by mass, 35 to 60% by mass, 25 to 50% by mass, or 35 to 50% by mass, relative to the total mass of the liquid crystal composition. When the content of the liquid crystal compound having a relative dielectric constant of less than 1000 is within the above range, a wider operating temperature range can be achieved.

[0098] 3. Device According to one aspect of the present invention, there is provided a device, which includes the liquid crystal compound or liquid crystal composition described above.

[0099] The liquid crystal compound or liquid crystal composition according to the present invention can exhibit ferroelectricity and can therefore be used in various devices. Examples include liquid crystal displays (LCDs), capacitor nonvolatile memory devices, sensors, etc. In this case, the type of liquid crystal display (LCD) is not particularly limited, and may be any of TN (Twisted Nematic), STN (Super Twisted Nematic), VA (Vertical Alignment), IPS (In-Plane Switching), OCB (Opticaly Compensated Bend) types, etc.

[0100] The element according to the present invention preferably includes a voltage application section, which allows the direction of polarization of the liquid crystal compound to be changed by an external electric field since the element contains a liquid crystal compound that can exhibit ferroelectricity.

[0101] The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.

[0102] Example 1 Synthesis of 3-fluoro-4-(3,4,5-trifluorophenyl)phenyl 4-n-butyryloxy-2,6-difluorobenzoate (Compound 1)

[0103] 5.74 g (44.1 mmol) of 3,5-difluorophenol (A-1) and 6.91 g (40.4 mmol) of benzyl bromide (A-2) were dissolved in 44 mL of dehydrated tetrahydrofuran (THF). 9.20 g (66.6 mmol) of potassium carbonate was added to this solution, and the reaction mixture was stirred at 60°C overnight. After cooling to room temperature, insoluble matter was removed by suction filtration, and the filtrate was concentrated and dried. The resulting yellow liquid was dissolved in 100 mL of n-hexane and washed three times with 100 mL of distilled water. The organic layer was dried over anhydrous sodium sulfate, and the solvent was removed. The residue was purified by silica gel column chromatography (eluent: n-hexane) to obtain benzyl 3,5-difluorophenyl ether (A-3) as a colorless liquid. Yield: 8.35 g (94.8%).

[0104] 7.00 g (31.8 mmol) of benzyl 3,5-difluorophenyl ether (A-3) was dissolved in 50 mL of anhydrous THF, and the solution was cooled to -78°C using dry ice / acetone under a nitrogen atmosphere. At this temperature, 25 mL (40 mmol, 1.3 equivalents) of a 1.6 M n-butyllithium n-hexane solution was gradually added and stirred for 10 minutes. 28 g (0.64 mol) of dry ice was then added at -78°C, and the mixture was stirred for 10 minutes, followed by stirring at room temperature for 30 minutes. 5 mL of distilled water was added to terminate the reaction, and the solvent was then removed. The residue was dissolved in 50 mL of distilled water, and 1 M hydrochloric acid was added to adjust the pH to 2-3. The resulting precipitate was collected by suction filtration, washed with distilled water, and dried under reduced pressure to obtain 4-benzyloxy-2,6-difluorobenzoic acid (A-4) as a white solid. Yield: 5.29 g (62.9%).

[0105] 5.28 g (20.0 mmol) of 4-benzyloxy-2,6-difluorobenzoic acid (A-4), 244 mg (2.00 mmol) of 4-dimethylaminopyridine (DMAP), and 5.33 g (22.0 mmol) of 3-fluoro-4-(3,4,5-trifluorophenyl)phenol (A-5) were dissolved in 100 mL of dichloromethane (DCM). 4.39 g (22.9 mmol) of 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (WSC) was added to this solution, and the reaction mixture was stirred overnight at room temperature. The resulting precipitate was collected by suction filtration and washed with DCM. The filtrate was concentrated and then added to methanol, and the resulting precipitate was also collected. These solids were mixed and dried under reduced pressure to obtain 3-fluoro-4-(3,4,5-trifluorophenyl)phenyl 4-benzyloxy-2,6-difluorobenzoate (A-6) as a white solid. Yield: 7.44 g (76.2%).

[0106] 7.33 g (15.0 mmol) of 3-fluoro-4-(3,4,5-trifluorophenyl)phenyl 4-benzyloxy-2,6-difluorobenzoate (A-6) was dissolved in 60 mL of THF, and 367 mg of 5 wt % palladium on carbon (Pd / C) was added. The mixture was stirred overnight at room temperature under a hydrogen atmosphere. The solid was separated by suction filtration, and the filtrate was concentrated. The residue was reprecipitated with an acetone / n-hexane mixture. After drying under reduced pressure, 3-fluoro-4-(3,4,5-trifluorophenyl)phenyl 2,6-difluoro-4-hydroxybenzoate (A-7) was obtained as a white solid. Yield: 5.57 g (93.3%).

[0107] 796 mg (2.19 mmol) of 3-fluoro-4-(3,4,5-trifluorophenyl)phenyl 2,6-difluoro-4-hydroxybenzoate (A-7) and 222 mg (2.19 mmol) of triethylamine were added to 10 mL of anhydrous THF and dissolved. After cooling this solution to 0°C in an ice bath, 5 mL of anhydrous THF solution containing 234 mg (2.20 mmol) of n-butyryl chloride (A-8) was slowly added. The reaction mixture was stirred at room temperature for one day, after which the resulting precipitate was filtered off by suction filtration, and the filtrate was concentrated. The residue was dissolved in DCM and washed three times with ultrapure water. The organic layer was dried over anhydrous sodium sulfate, and then the solvent was removed. The resulting solid was purified by silica gel column chromatography (eluent: n-hexane / DCM=1:1 (volume ratio)). Further, recrystallization was carried out using a mixed solvent of n-hexane / DCM to obtain 3-fluoro-4-(3,4,5-trifluorophenyl)phenyl 4-n-butyryloxy-2,6-difluorobenzoate (Compound 1) as a white solid. Yield: 804 mg (yield: 85.8%). １ H NMR (400MHz, CDCl ３ , ppm): δ 7.46-7.42 (m, 1H, phenyl), 7.20-7.15 (m, 4H, phenyl), 6.90 (d, 2H, J = 8.8 Hz, phenyl), 2.58 (t, 2H, J = 7.2 Hz, -CH ２ -C=O), 1.80 (sext, 2H, J = 7.4 Hz, CH ３ -CH ２ -), 1.06 (t, 3H, J = 7.2 Hz, CH ３ -). HRMS (FAB+) m / z: calcd for C ２３ H １４ F ６ O ４ :468.0796;found:469.0875(M+H).

[0108] According to the above-described production method, it was possible to produce the liquid crystal compound using inexpensive raw materials. Furthermore, excluding the steps of protecting and deprotecting the phenolic hydroxyl group, the target liquid crystal compound could be produced in just three steps. Furthermore, since the compound does not have a 1,3-dioxane ring, geometric isomers (cis and trans isomers) do not occur, and therefore no separation and purification step is required. As a result, the target liquid crystal compound could be produced in high yield.

[0109]

[0110] Example 2 Synthesis of 4-(4-cyano-3,5-difluorophenyl)-3-fluorophenyl 4-n-butyryloxy-2,6-difluorobenzoate (Compound 2)

[0111] 2.86 g (22.0 mmol) of 3,5-difluorophenol (A-1) and 2.20 g (21.7 mmol) of triethylamine were dissolved in 20 mL of DCM. 3.00 g (19.9 mmol) of tert-butyldimethylsilyl chloride was gradually added to this solution at 0°C, and the reaction mixture was stirred at room temperature for 2 days. The resulting precipitate was separated by suction filtration, and the filtrate (DCM solution) was washed three times with distilled water. The organic layer was dried over anhydrous sodium sulfate, the solvent was removed, and the mixture was dried under reduced pressure to obtain tert-butyldimethylsilyl 3,5-difluorophenyl ether (A-9) as a pale yellow liquid. Yield: 4.87 g (>99%).

[0112] 9.54 g (39.0 mmol) of tert-butyldimethylsilyl 3,5-difluorophenyl ether (A-9) was dissolved in 30 mL of anhydrous THF and cooled to -78°C in dry ice-acetone under a nitrogen atmosphere. At this temperature, 30 mL (48 mmol, 1.2 equivalents) of a 1.6 M n-butyllithium n-hexane solution was slowly added dropwise, followed by stirring for 10 minutes. 3.14 g (43.0 mmol) of anhydrous N,N-dimethylformamide (DMF) was then added and stirred at -78°C for 10 minutes. The mixture was returned to room temperature, and distilled water was added to terminate the reaction. The organic solvent was removed, and the residue was added to distilled water. The pH of this aqueous solution was adjusted to approximately 4 with 1 M hydrochloric acid, and the resulting precipitate was collected by suction filtration. After drying under reduced pressure and washing with DCM, 2,6-difluoro-4-hydroxybenzaldehyde (A-10) was obtained as a white solid. Yield: 4.21 g (68.2%).

[0113] A 20 mL DCM solution of 1.02 g (6.45 mmol) of 2,6-difluoro-4-hydroxybenzaldehyde (A-10) and 715 mg (7.07 mmol) of triethylamine was cooled to 0°C in an ice bath, and 3 mL of a DCM solution of 750 mg (7.04 mmol) of n-butyryl chloride (A-8) was slowly added dropwise thereto. The reaction mixture was stirred at room temperature for 2 days, and then additional DCM was added. The mixture was separated and washed with aqueous sodium bicarbonate and then distilled water. The organic layer was dried over anhydrous sodium sulfate and concentrated. The resulting residue was purified by silica gel column chromatography (eluent: n-hexane / DCM = 1:1 (volume ratio)) to give 4-n-butyryloxy-2,6-difluorobenzaldehyde (A-11) as a colorless solution. Yield: 1.43 g (94.3%).

[0114] To 2.0 mL of a dimethyl sulfoxide (DMSO) solution of 1.34 g (5.87 mmol) of 4-n-butyryloxy-2,6-difluorobenzaldehyde (A-11), 2.10 g (29.9 mmol) of 2-methyl-2-butene was added, followed by 5.0 mL of an aqueous solution of 2.17 g (24.0 mmol) of sodium dihydrogen phosphate. This mixture was cooled in an ice bath, and 4.0 mL of an aqueous solution of 2.17 g (24.0 mmol) of sodium chlorite was added. The reaction mixture was stirred at 0°C for 2 hours. After stirring at room temperature for another 2 hours, 1 M hydrochloric acid was added to adjust the pH to approximately 3. The resulting precipitate was collected by suction filtration, washed with distilled water, and dried under reduced pressure to obtain 4-n-butyryloxy-2,6-difluorobenzoic acid (A-12) as a white solid. Yield: 1.01 g (70.1%).

[0115] 977 mg (4.00 mmol) of 4-n-butyryloxy-2,6-difluorobenzoic acid (A-12) and 1.20 g (4.82 mmol) of 4-(4-cyano-3,5-difluorophenyl)-3-fluorophenol (A-13) were added to 30 mL of DCM. 1.05 g (5.48 mmol) of WSC was gradually added to this mixture, and the reaction mixture was stirred at room temperature for 2.5 hours. 50 mL of DCM was then added, and the mixture was washed three times with 50 mL of ultrapure water. The organic layer was dried over anhydrous sodium sulfate, the solvent was removed, and the residue was purified by silica gel column chromatography (n-hexane / DCM = 1:2 (volume ratio)). Subsequently, recrystallization was performed from an n-hexane / DCM mixture to obtain 4-(4-cyano-3,5-difluorophenyl)-3-fluorophenyl 4-n-butyryloxy-2,6-difluorobenzoate (Compound 2) as a white solid. Yield: 638 mg (33.6%). １ H NMR (400MHz, CDCl ３ , ppm): δ 7.52-7.48 (m, 1H, phenyl), 7.28-7.21 (m, 4H, phenyl), 6.91 (d, 2H, J = 9.2 Hz, phenyl), 2.59 (t, 2H, J = 7.4 Hz, -CH ２ -COO-), 1.84-1.75 (m, 2H, CH ３ -CH ２-), 1.06 (t, 3H, J = 7.4 Hz, CH ３ -). HRMS (FAB+) m / z: calcd for C ２４ H １４ F ５ NO ４ :475.0843;found:476.0923(M+H).

[0116]

[0117] Example 3 Synthesis of 4-(3,5-difluoro-4-nitrophenyl)-3-fluorophenyl 4-n-butyryloxy-2,6-difluorobenzoate (Compound 3)

[0118] 900 mg (3.69 mmol) of 4-n-butyryloxy-2,6-difluorobenzoic acid (A-12) and 1.15 g (4.27 mmol) of 4-(3,5-difluoro-4-nitrophenyl)-3-fluorophenol (A-14) were added to 10 mL of DCM. 860 mg (4.49 mmol) of WSC was gradually added to this mixture, and the reaction mixture was stirred at room temperature for 2 hours. 100 mL of DCM was then added, and the mixture was washed three times with 100 mL of ultrapure water. The organic layer was dried over anhydrous sodium sulfate, the solvent was removed, and the resulting crude product was purified by silica gel column chromatography (eluent: n-hexane / DCM = 1:1 (volume ratio)). Recrystallization was then performed using a mixed solvent of n-hexane / DCM to obtain 4-(3,5-difluoro-4-nitrophenyl)-3-fluorophenyl 4-n-butyryloxy-2,6-difluorobenzoate (Compound 3) as a white solid. Yield: 724 mg (yield: 40.0%). １ H NMR (400MHz, DMSO-d ６ , ppm): δ 7.84-7.79 (m, 3H, phenyl), 7.55 (dd, 1H, J = 12.0, 2.0 Hz, phenyl), 7.38-7.34 (m, 3H, phenyl), 2.62 (t, 2H, J = 7.0Hz, -CH ２ -COO-), 1.72-1.63 (m, 2H, CH ３ -CH ２-), 0.99 (t, 3H, J = 7.6 Hz, CH ３ -). HRMS (FAB+) m / z: calcd for C ２３ H １４ F ５ NO ６ :495.0741;found:496.0821(M+H).

[0119]

[0120] Example 4 Synthesis of 3-fluoro-4-(3,4,5-trifluorophenyl)phenyl 4-n-butyryloxybenzoate (Compound 4)

[0121] 4.56 g (20.0 mmol) of 4-benzyloxybenzoic acid (A-15), 5.33 g (22.0 mmol) of 3-fluoro-4-(3,4,5-trifluorophenyl)phenol (A-5), and 2.44 g (20.0 mmol) of DMAP were dissolved in 100 mL of DCM. 4.50 g (23.5 mmol) of WSC was added to this solution, and the reaction mixture was stirred at room temperature overnight. The resulting precipitate was collected by suction filtration and washed with DCM to obtain the target product. The filtrate was washed separately with dilute hydrochloric acid and then distilled water, and the organic layer was dried over anhydrous sodium sulfate and the solvent was removed. The residue was then washed with methanol to obtain 3-fluoro-4-(3,4,5-trifluorophenyl)phenyl 4-benzyloxybenzoate (A-16). Yield: 8.69 g (96.0%).

[0122] To 100 mL of a THF solution containing 8.69 g (19.2 mmol) of 3-fluoro-4-(3,4,5-trifluorophenyl)phenyl 4-benzyloxybenzoate (A-16), 900 mg of 5 wt % Pd / C (10 wt % relative to the substrate) was added, and the mixture was stirred at room temperature under a hydrogen atmosphere for 2 days. The solid was filtered off, and the filtrate was concentrated and reprecipitated with an acetone / n-hexane mixed solvent to obtain 3-fluoro-4-(3,4,5-trifluorophenyl)phenyl 4-hydroxybenzoate (A-17) as a white solid. Yield: 6.33 g (90.9%).

[0123] 1.09 g (3.00 mmol) of 3-fluoro-4-(3,4,5-trifluorophenyl)phenyl 4-hydroxybenzoate (A-17) and 334 mg (3.30 mmol) of triethylamine were added to 30 mL of DCM and cooled to 0 °C in an ice bath. 330 mg (3.30 mmol) of n-butyryl chloride (A-8) was slowly added dropwise thereto, and the reaction mixture was stirred at room temperature for 1 hour. The resulting precipitate was filtered off, and 50 mL of the filtrate was washed twice with 50 mL of distilled water and then with 50 mL of ultrapure water. After drying over anhydrous sodium sulfate, the solvent was removed, and 1.53 g of the resulting crude product was purified by silica gel column chromatography (eluent: n-hexane / DCM = 1:1 → 1:2 (volume ratio)). Thereafter, recrystallization was carried out using a mixed solvent of n-hexane and DCM to obtain 3-fluoro-4-(3,4,5-trifluorophenyl)phenyl 4-n-butyryloxybenzoate (Compound 4) as a white solid. Yield: 1.15 g (85.8%). １ H NMR (400MHz, CDCl ３ , ppm): δ 8.24 (d, 2H, J = 8.8 Hz, phenyl), 7.46-7.41 (m, 1H, phenyl), 7.28-7.26 (m, 2H, phenyl), 7.19 (t, 2H, J = 7.2 Hz, phenyl ),7.14-7.10(m, 2H, phenyl )2.60 (t, 2H, J = 7.2 Hz, -CH ２ -C=O), 1.86-1.77 (m, 2H, CH ３ -CH ２ -), 1.07 (t, 3H, J = 7.4 Hz, CH ３ -). HRMS (FAB+) m / z: calcd for C ２３ H １６ F ４ O ４ :432.0985;found:433.1064(M+H).

[0124]

[0125] Example 5 Synthesis of 3-fluoro-4-(3,4,5-trifluorophenyl)phenyl 4-acetyloxy-2,6-difluorobenzoate (Compound 5)

[0126] 3-Fluoro-4-(3,4,5-trifluorophenyl)phenyl 4-acetyloxy-2,6-difluorobenzoate (Compound 5) was synthesized in the same manner as in Example 1, except that 3-fluoro-4-(3,4,5-trifluorophenyl)phenyl 2,6-difluoro-4-hydroxybenzoate (A-7) was reacted with acetyl chloride instead of n-butyryl chloride (A-8).

[0127]

[0128] Example 6 Synthesis of 3-fluoro-4-(3,4,5-trifluorophenyl)phenyl 2,6-difluoro-4-propionyloxybenzoate (Compound 6)

[0129] 3-Fluoro-4-(3,4,5-trifluorophenyl)phenyl 2,6-difluoro-4-propionyloxybenzoate (Compound 6) was synthesized in the same manner as in Example 1, except that 3-fluoro-4-(3,4,5-trifluorophenyl)phenyl 2,6-difluoro-4-hydroxybenzoate (A-7) was reacted with propionyl chloride instead of n-butyryl chloride (A-8).

[0130]

[0131] Example 7 Synthesis of 3-fluoro-4-(3,4,5-trifluorophenyl)phenyl 2,6-difluoro-4-valeryloxybenzoate (Compound 7)

[0132] 3-Fluoro-4-(3,4,5-trifluorophenyl)phenyl 2,6-difluoro-4-valeryloxybenzoate (Compound 7) was synthesized in the same manner as in Example 1, except that 3-fluoro-4-(3,4,5-trifluorophenyl)phenyl 2,6-difluoro-4-hydroxybenzoate (A-7) was reacted with valeryl chloride instead of n-butyryl chloride (A-8).

[0133]

[0134] Example 8 Synthesis of 3-fluoro-4-(3,4,5-trifluorophenyl)phenyl 2,6-difluoro-4-isovaleryloxybenzoate (Compound 8)

[0135] 3-Fluoro-4-(3,4,5-trifluorophenyl)phenyl 2,6-difluoro-4-isovaleryloxybenzoate (Compound 8) was synthesized in the same manner as in Example 1, except that 3-fluoro-4-(3,4,5-trifluorophenyl)phenyl 2,6-difluoro-4-hydroxybenzoate (A-7) was reacted with isovaleryl chloride instead of n-butyryl chloride (A-8).

[0136]

[0137] Example 9 Synthesis of 3-fluoro-4-(3,4,5-trifluorophenyl)phenyl 2,6-difluoro-4-(DL-2-methylbutyryloxy)benzoate (Compound 9)

[0138] 3-Fluoro-4-(3,4,5-trifluorophenyl)phenyl 2,6-difluoro-4-(DL-2-methylbutyryloxy)benzoate (Compound 9) was synthesized in the same manner as in Example 1, except that 3-fluoro-4-(3,4,5-trifluorophenyl)phenyl 2,6-difluoro-4-hydroxybenzoate (A-7) was reacted with DL-2-methylbutyryl chloride instead of n-butyryl chloride (A-8).

[0139]

[0140] Example 10 Synthesis of 3-fluoro-4-(3,4,5-trifluorophenyl)phenyl 4-crotonoyloxy-2,6-difluorobenzoate (Compound 10)

[0141] 3-Fluoro-4-(3,4,5-trifluorophenyl)phenyl 4-crotonoyloxy-2,6-difluorobenzoate (Compound 10) was synthesized in the same manner as in Example 1, except that 3-fluoro-4-(3,4,5-trifluorophenyl)phenyl 2,6-difluoro-4-hydroxybenzoate (A-7) was reacted with crotonic acid instead of n-butyryl chloride (A-8).

[0142]

[0143] Example 11 Synthesis of 3-fluoro-4-(3,4,5-trifluorophenyl)phenyl 2,6-difluoro-4-(trans-3-pentenoyloxy)benzoate (Compound 11)

[0144] 3-Fluoro-4-(3,4,5-trifluorophenyl)phenyl 2,6-difluoro-4-(trans-3-pentenoyloxy)benzoate (Compound 11) was synthesized in the same manner as in Example 1, except that 3-fluoro-4-(3,4,5-trifluorophenyl)phenyl 2,6-difluoro-4-hydroxybenzoate (A-7) was reacted with trans-3-pentenoic acid instead of n-butyryl chloride (A-8).

[0145]

[0146] Example 12 Synthesis of 3-fluoro-4-(3,4,5-trifluorophenyl)phenyl 4-propionyloxybenzoate (Compound 12)

[0147] 3-Fluoro-4-(3,4,5-trifluorophenyl)phenyl 4-propionyloxybenzoate (Compound 12) was synthesized in the same manner as in Example 4, except that 3-fluoro-4-(3,4,5-trifluorophenyl)phenyl 4-hydroxybenzoate (A-17) was reacted with propionyl chloride instead of n-butyryl chloride (A-8).

[0148]

[0149] Example 13 Synthesis of 3-fluoro-4-(3,4,5-trifluorophenyl)phenyl 4-valeryloxybenzoate (Compound 13)

[0150] 3-Fluoro-4-(3,4,5-trifluorophenyl)phenyl 4-valeryloxybenzoate (Compound 13) was synthesized in the same manner as in Example 4, except that 3-fluoro-4-(3,4,5-trifluorophenyl)phenyl 4-hydroxybenzoate (A-17) was reacted with valeryl chloride instead of n-butyryl chloride (A-8).

[0151]

[0152] Comparative Examples 1 to 4 In Comparative Examples 1 to 4, the following compounds were used.

[0153] [Evaluation] The liquid crystal compounds of Examples 1 to 4 and Comparative Examples 1 to 4 were subjected to various evaluations.

[0154] (Measurement of Phase Transition Temperature) Differential scanning calorimetry (DSC) was performed using a DSC 1 STARe system (manufactured by METTLER TOLEDO) at a rate of 5°C / min. Specifically, the exothermic peak and endothermic peak were measured in the order of first heating, first cooling, second heating, and second cooling.

[0155] The results are shown in Table 1 below. The phase transition from the crystalline phase to Phase A is the data of the endothermic peak during the first heating, and the phase transitions to the other phases are the data of the exothermic peak during the second cooling. Phase transitions below the melting point are monotropic (monotropic) phase transitions that occur in a supercooled state during cooling, and the other phase transitions are enantiotropic (mutually mutated) phase transitions.

[0156]

[0157] (Identification of Each Phase) Phases A to E observed in Examples 1 to 4 and Comparative Examples 1 to 4 were identified by polarizing microscope (POM) observation, small angle X-ray scattering (SAXS) measurement, and polarization reversal current measurement.

[0158] (1) Preparation of Measurement Cells A plain glass cell, a non-alignment treated cell, and a vertical alignment (homeotropic alignment) treated cell were prepared.

[0159] The non-alignment treated cell was prepared by injecting a liquid crystal compound in a liquid crystal state into a plain glass cell (manufactured by E.H.C. Co.) (area: 1 m ２ , cell thickness: 10 μm). A vertically aligned (homeotropic alignment) treated cell was fabricated as follows. Specifically, a glass substrate with an indium tin oxide (ITO) electrode was subjected to ultrasonic cleaning in Cicaclean, distilled water, and acetone, followed by ozone cleaning. A cyclopentane solution of octadecyltrimethoxysilane (concentration: 2 vol%) as a surface modifier was spin-coated at 3000 rpm for 30 seconds. After baking at 130°C for 10 minutes, ultrasonic cleaning was performed in cyclopentanone and then in ethanol. After vacuum baking at 130°C for 3 hours, a sandwich cell was assembled using a 10 μm-thick PET film. A liquid crystal compound was injected into the sandwich cell to fabricate a vertically aligned (homeotropic alignment) treated cell.

[0160] (2) Polarizing microscope (POM) observation: A polarizing microscope, ECLIPSE LV100NPO L-WinP (Nikon Corporation), and a microscope digital camera, DS-Ri2 camera (Nikon Corporation), were used. A non-aligned cell and a vertically aligned (homeotropic alignment) cell were used as measurement cells. The measurement cells were placed on a temperature-controlled stage, which was then placed on the stage of the polarizing microscope. The temperature was controlled at a temperature increase / decrease rate of 5°C / min, and the cells were observed under crossed Nicols.

[0161] In the liquid crystal compound of Example 1, when the A phase was observed by POM, a ferroelectric nematic phase (N Ｆ The striped texture characteristic of the ferroelectric nematic phase (N phase) was observed, which suggests that the A phase is a ferroelectric nematic phase (N phase). Ｆ Furthermore, as a result of POM observation, it was determined that the B phase was a nematic phase (N phase) and the C phase was an isotropic phase (Iso phase).

[0162] In the liquid crystal compounds of Examples 2 and 3, when the A phase was observed by POM, a ferroelectric nematic phase (N Ｆ The striped texture characteristic of the ferroelectric nematic phase (N phase) was observed, which suggests that the A phase is a ferroelectric nematic phase (N phase). Ｆ Furthermore, as a result of POM observation, it was determined that the C phase was a nematic phase (N phase) and the D phase was an isotropic phase (Iso phase). Ｆ The B phase, which is located between the C phase (N phase) and the A phase (N phase), has a sandy texture similar to that observed in the C phase (N phase). Ｆ The striped texture observed in the nematic phase (N Ｘ It was identified as a phase.

[0163] In the liquid crystal compound of Example 4, when the A phase was observed by POM, a ferroelectric smectic phase (Sm Ｆ The mosaic texture characteristic of the ferroelectric smectic phase (Sm Ｆ Furthermore, as a result of POM observation, it was determined that the B phase was a nematic phase (N phase) and the C phase was an isotropic phase (Iso phase).

[0164] 1A and 1B are POM images of the A phase of the liquid crystal compounds of Examples 1 to 4 measured using a non-alignment treated cell. FIG. 1A shows the ferroelectric nematic phase (N Ｆ phase), and FIG. 1B shows the ferroelectric nematic phase (N Ｆ phase), and FIG. 1C shows the ferroelectric nematic phase (N Ｆ phase), and FIG. 1D shows the ferroelectric smectic phase (Sm Ｆ phase).

[0165] (3) Small-angle X-ray scattering (SAXS) measurement Ferroelectric smectic phase (Sm Ｆ The phase A of the liquid crystal compound of Example 4, which was identified as a phase A, was further analyzed by small-angle X-ray scattering (SAXS) measurements. Specifically, small-angle X-ray scattering (SAXS) measurements were performed using the Kyushu University Beamline (BL06) installed at the Saga Prefectural Kyushu Synchrotron Light Research Center (SAGA-LS). The crystalline compound was injected into a hole stage (diameter: 3 mm, depth: 1 mm) equipped with a pair of magnets (magnetic field: approximately 560 mT), and the stage was positioned so that the direction of the magnetic field (director direction of the liquid crystal compound) was perpendicular to the direction of X-ray irradiation. Measurements were performed with an aging time of 1 minute, an exposure time of 10 seconds, and cooling operation at 90 to 145°C. The obtained SAXS images were integrated to obtain a one-dimensional profile.

[0166] As a result of the measurement, strong first-order scattering, which is seen in the smectic A phase, was obtained, and therefore the liquid crystal compound of Example 4 was found to be in the A phase, i.e., the ferroelectric smectic phase (Sm Ｆ phase) is a ferroelectric smectic A phase (SmA Ｆ It was identified as a phenotype.

[0167] (4) Measurement of polarization reversal current An apparatus was used, which was equipped with an arbitrary waveform generator 2411B (manufactured by Toyo Corporation), an analog-digital converter Wave Book / 516A (manufactured by Toyo Corporation), and a current-voltage / charge-voltage (IV / QV) converter Model 6254C (manufactured by Toyo Corporation). A vertically aligned (homeotropic alignment) treated cell was used as the measurement cell.

[0168] The polarization inversion current was measured by the triangular wave method at an applied voltage of 20 Vpp (±10 V) and a frequency of 10 to 200 Hz, and the measured current was integrated to obtain an electric flux density-electric field (DE) curve.

[0169] Fig. 2 shows the DE curves of the liquid crystal compounds of Examples 1 to 4. Fig. 2A shows the DE curve (frequency: 100 Hz) of the liquid crystal compound of Example 1, Fig. 2B shows the DE curve (frequency: 200 Hz) of the liquid crystal compound of Example 2, Fig. 2C shows the DE curve (frequency: 100 Hz) of the liquid crystal compound of Example 3, and Fig. 2D shows the DE curve (frequency: 10 Hz) of the liquid crystal compound of Example 4.

[0170] The liquid crystal compound of Example 1 exhibited hysteresis in the DE curve at 95 to 100°C, which indicates the A phase. The liquid crystal compound of Example 2 exhibited hysteresis in the DE curve at 80 to 100°C, which indicates the A phase. The liquid crystal compound of Example 3 exhibited hysteresis in the DE curve at 60 to 100°C, which indicates the A phase. The liquid crystal compound of Example 4 exhibited hysteresis in the DE curve at 90 to 120°C, which indicates the A phase. Therefore, it was confirmed that the A phases of Examples 1 to 4 all had ferroelectricity.

[0171] (5) Results The phases A to F identified from the results of (2) to (4) above are as shown in Table 2 below. Ｆ "N phase" is a ferroelectric nematic phase, "N phase" is a nematic phase, and "N ｘ Phase" is N Ｆ A phase that can occur on the high temperature side of the N phase and the low temperature side of the N phase, Ｆ It is an unexplained nematic phase different from the N phase and the N phase. Ｆ 'Phase' is N Ｆ A ferroelectric nematic phase that can occur at low temperatures is N Ｆ It is an unexplained ferroelectric nematic phase that is different from the SmA phase. Ｆ phase" is a ferroelectric smectic A phase, and "SmA Ｆ 'Phase' is SmA Ｆ A ferroelectric smectic A phase that can occur at low temperatures is SmA ＦThe "Iso phase" is an isotropic phase, and the "Smectic A phase" is an unexplained ferroelectric phase that is different from the "Iso phase."

[0172]

[0173] From the results in Table 1, the liquid crystal compounds of Examples 1 to 4 have a crystalline phase, N Ｆ Phase or SmA Ｆ In addition to the N-phase, N-phase, and Iso-phase, Ｘ It was found that the phase transition behavior was such that the liquid crystal compounds of Examples 1 to 4 were capable of forming a phase. That is, it was found that the liquid crystal compounds of Examples 1 to 4 had simpler phase transition behavior than the liquid crystal compounds of Comparative Examples 1 to 4. It was also found that the liquid crystal compounds of Examples 1 to 4 had lower phase transition temperatures than the liquid crystal compounds of Comparative Examples 1 to 4. For example, the liquid crystal compounds of Examples 1 to 4 do not have the 1,3-dioxane ring that the liquid crystal compounds of Comparative Examples 1 to 4 have, and therefore it is thought that the phase transition was simplified by reducing the intermolecular interaction, thereby lowering the phase transition temperature.

[0174] (Dipole Moment) The dipole moments of the liquid crystal compounds of Examples 1 to 4 and Comparative Examples 1 to 4 were calculated from the most stable structures obtained by quantum chemical calculations (density functional theory, 6-31+G(2d,p)) using Gaussian 16. The results are shown in Table 3 below.

[0175]

[0176] The results in Table 3 show that Examples 1 to 4 have lower dipole moments than the corresponding Comparative Examples 1 to 4. Conventionally, it has been thought that the larger the dipole moment of a liquid crystal compound, the more advantageous it is for the development of ferroelectricity. However, since Examples 1 to 4 have excellent dielectric properties as described below despite having a low dipole moment, the results of Examples 1 to 4 are surprising and contrary to conventional knowledge.

[0177] (Dielectric Properties) The dielectric properties of the liquid crystal compounds of Examples 1 to 4 were evaluated by dielectric relaxation spectrum measurement. The dielectric relaxation spectrum measurement was performed as follows. Measurement was performed using an impedance / gain phase analyzer SI1260 (manufactured by Solatron Metrology) at an applied voltage of 0.1 Vrms. In addition, the vertically aligned (homeotropic alignment) treated cell prepared in the above "Identification of Each Phase" was used as the sample. First, using an empty cell, the resistance and capacitance of the indium tin oxide (ITO) electrode were measured, and the obtained values ​​were used to correct the impedance of the sample to measure the dielectric constant.

[0178] The results are shown in Tables 4-1 and 4-2 below. Table 4-1 shows the results measured at a frequency of 100 Hz, and Table 4-2 shows the results measured at a frequency of 1000 Hz. Figure 3 is a logarithmic graph showing the relationship between the relative dielectric constant and temperature at a frequency of 1000 Hz for the liquid crystal compounds of Examples 1 to 4.

[0179]

[0180] From the results in Tables 4-1 and 4-2 and FIG. 3, it was found that the liquid crystal compounds of Examples 1 to 4 had a relative dielectric constant of at least 100 or more and exhibited excellent dielectric properties. The compounds of Examples 1 to 3 exhibited an extremely high relative dielectric constant of 10,000 or more. Furthermore, the compounds of Examples 2 and 3 exhibited a high relative dielectric constant over a wide temperature range.

[0181] [Examples 14 to 19: Liquid Crystal Compositions] Liquid crystal compositions were prepared by mixing the liquid crystal compounds of Examples 2 and 3 and Compound A having a relative dielectric constant of a nematic phase of less than 1000 as shown in Table 5, heating the mixture, and then cooling it. Table 5 also lists Examples 2 and 3, as well as Comparative Example 5 in which Compound A was used alone.

[0182]

[0183] The structure of Compound A is as follows:

[0184] [Evaluation] Differential scanning calorimetry (DSC), polarizing microscope (POM) observation, polarization inversion current measurement, and dielectric relaxation spectrum measurement were performed on the liquid crystal compositions of Examples 14 to 19 and the liquid crystal compound of Comparative Example 5 in the same manner as in Examples 1 to 4. The results are shown in Table 6 below. FIG. 4 is a graph showing the changes in phase transition temperature of the liquid crystal compositions of Examples 14 to 19. FIG. 4A shows data for Examples 2, 14 to 16, and 3 (horizontal axis: content of the liquid crystal compound of Example 3, vertical axis: phase transition temperature), and FIG. 4B shows data for Examples 15, 17 to 19, and Comparative Example 5 (horizontal axis: content of the liquid crystal compound of Compound A, vertical axis: phase transition temperature).

[0185] All phase transitions are from the second cooling. Phase transitions below the melting point are monotropic (monotropic) phase transitions that occur in a supercooled state during cooling, while all others are enantiotropic (mutually mutated) phase transitions.

[0186] From the results of Table 6 and FIG. 4, in the liquid crystal compositions of Examples 14 to 16 in which the liquid crystal compounds of Examples 2 and 3 were mixed, N Ｆ The temperature at which the liquid crystal compound of Example 2 or 3 transitions from the N phase to the crystalline phase is 40 to 43°C, which is lower than the temperature at which the liquid crystal compound of Example 2 or 3 transitions alone (53°C or 60°C). Ｆ The temperature range in which the phase appears could be expanded.

[0187] In addition, in Examples 17 to 19 in which Compound A was further mixed with Example 15 (the equimolar mixture of the liquid crystal compounds of Examples 2 and 3), N Ｆ It was found that the temperature at which the phase transition from the crystalline phase to the crystalline phase occurs is 24 to 30°C and further decreases.

Claims

1. The following formula (1-1) or formula (2-1): (In the above formula, R １ represents hydrogen, a polymerizable group, or an alkyl group having 1 to 20 carbon atoms, and in this case, any —CH ２ - may be replaced by -O-, -S-, -COO-, -OCO-, -CH=CH-, -CF=CF-, or -C≡C-, and any hydrogen in the alkyl may be replaced by a halogen; X is hydrogen, a polymerizable group, a halogen, -CN, or -NO ２ , -NCO, -NCS, -CH ２ F, -CHF ２ , -CF ３ , -OCH ２ F, -OCHF ２ , -OCF ３ , alkyl having 1 to 3 carbon atoms, in which any —CH ２ - may be replaced by -O-, -S-, -COO-, -OCO-, -CH=CH-, -CF=CF-, or -C≡C-; any hydrogen in the alkyl may be replaced by halogen; ３ may be replaced by —CN, Ar １ , Ar ２ , Ar ３ , Ar ４ , and Ar ５ are each independently substituted or unsubstituted arylene, substituted or unsubstituted heteroarylene, １ , A ２ , and A ３ are each independently a single bond or alkylene having 1 to 8 carbon atoms, and any —CH ２ - may be replaced by -O-, -S-, -COO-, -OCO-, -CSO-, -OCS-, -N=N-, -CH=N-, -N=CH-, -N(O)=N-, -N=N(O)-, -CH=CH-, -CF=CF- or -C≡C-, any hydrogen in the alkylene may be replaced by a halogen, and n and m are each independently 0 or 1.

2. The following formula (1-2) or formula (2-2): (In the above formula, R １ represents hydrogen, a polymerizable group, or an alkyl group having 1 to 20 carbon atoms, and in this case, any —CH ２ - may be replaced by -O-, -S-, -COO-, -OCO-, -CH=CH-, -CF=CF-, or -C≡C-, and any hydrogen in the alkyl may be replaced by a halogen; R ２ each independently represents a polymerizable group, a halogen, —CN, or —NO ２ , -NCO, -NCS, -CH ２ F, -CHF ２ , -CF ３ , -OCH ２ F, -OCHF ２ , -OCF ３ , alkyl having 1 to 3 carbon atoms, in which any —CH ２ - may be replaced by -O-, -S-, -COO-, -OCO-, -CH=CH-, -CF=CF-, or -C≡C-; any hydrogen in the alkyl may be replaced by halogen; ３ may be replaced by —CN, and X is hydrogen, a polymerizable group, a halogen, —CN, or —NO ２ , -NCO, -NCS, -CH ２ F, -CHF ２ , -CF ３ , -OCH ２ F, -OCHF ２ , -OCF ３ , alkyl having 1 to 3 carbon atoms, in which any —CH ２ - may be replaced by -O-, -S-, -COO-, -OCO-, -CH=CH-, -CF=CF-, or -C≡C-; any hydrogen in the alkyl may be replaced by halogen; ３ may be replaced by -CN, ３ represents a single bond, an alkylene having 1 to 8 carbon atoms, and any —CH ２ - may be replaced by -O-, -S-, -COO-, -OCO-, -CSO-, -OCS-, -N=N-, -CH=N-, -N=CH-, -N(O)=N-, -N=N(O)-, -CH=CH-, -CF=CF- or -C≡C-; any hydrogen in the alkylene may be replaced by a halogen; and each p is independently an integer of 0 to 4.

3. The following formulas (1-3) to (2-4): (In the above formula, R １ represents hydrogen, a polymerizable group, or an alkyl group having 1 to 20 carbon atoms, and in this case, any —CH ２ - may be replaced by -O-, -S-, -COO-, -OCO-, -CH=CH-, -CF=CF-, or -C≡C-, and any hydrogen in the alkyl may be replaced by a halogen; R ３ are each independently hydrogen, a polymerizable group, a halogen, —CN, or —NO ２ , -NCO, -NCS, -CH ２ F, -CHF ２ , -CF ３ , -OCH ２ F, -OCHF ２ , -OCF ３ , alkyl having 1 to 3 carbon atoms, in which any —CH ２ - may be replaced by -O-, -S-, -COO-, -OCO-, -CH=CH-, -CF=CF-, or -C≡C-; any hydrogen in the alkyl may be replaced by halogen; ３ may be replaced by —CN, and X is hydrogen, a polymerizable group, a halogen, —CN, or —NO ２ , -NCO, -NCS, -CH ２ F, -CHF ２ , -CF ３ , -OCH ２ F, -OCHF ２ , -OCF ３ , alkyl having 1 to 3 carbon atoms, in which any —CH ２ - may be replaced by -O-, -S-, -COO-, -OCO-, -CH=CH-, -CF=CF-, or -C≡C-; any hydrogen in the alkyl may be replaced by halogen; ３ The liquid crystal compound according to claim 1 , wherein 4. The following formulas (1) to (13): The liquid crystal compound according to claim 1 , represented by:

5. The liquid crystal compound according to claim 1, which has a relative dielectric constant of 1,000 or more.

6. The liquid crystal compound according to claim 1, having a dipole moment of 8.5 D or less.

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

8. A liquid crystal composition comprising two or more liquid crystal compounds according to claim 1.

9. The liquid crystal composition according to claim 7, further comprising a liquid crystal compound having a relative dielectric constant of less than 1,000.

10. The liquid crystal composition according to claim 8, further comprising a liquid crystal compound having a relative dielectric constant of less than 1,000.

11. A device comprising the liquid crystal compound according to any one of claims 1 to 6 or the liquid crystal composition according to any one of claims 7 to 10.

12. The device according to claim 11, further comprising a voltage application section.

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