CN113717147A

CN113717147A - Compound, liquid crystal composition and liquid crystal display element

Info

Publication number: CN113717147A
Application number: CN202110565039.8A
Authority: CN
Inventors: 稲垣顺一; 木村敬二; 高桥道子
Original assignee: JNC Corp; JNC Petrochemical Corp
Current assignee: JNC Corp; JNC Petrochemical Corp
Priority date: 2020-05-26
Filing date: 2021-05-24
Publication date: 2021-11-30
Also published as: JP2021187742A; TW202206579A

Abstract

The present invention addresses the problem of providing a liquid crystalline compound that sufficiently satisfies at least one of high stability to heat or light, high clearing point (or high upper limit temperature), low lower limit temperature of the liquid crystal phase, low viscosity, appropriate optical anisotropy, large dielectric anisotropy, appropriate elastic constant, and good compatibility with other liquid crystalline compounds, a liquid crystal composition containing the compound, and a liquid crystal display element including the composition. The means of the present invention is a compound represented by formula (1), a liquid crystal composition containing the compound, and a liquid crystal display element comprising the composition.

Description

Compound, liquid crystal composition and liquid crystal display element

Technical Field

The present invention relates to a liquid crystal compound, a liquid crystal composition, and a liquid crystal display element. More specifically, the present invention relates to a liquid crystalline compound having a thiophene ring, a liquid crystal composition containing the compound and having a nematic phase, and a liquid crystal display device including the composition.

Background

Liquid crystal display elements are widely used for displays of personal computers, televisions, and the like. The device utilizes physical properties such as optical anisotropy and dielectric anisotropy of a liquid crystalline compound. As the operation mode of the liquid crystal display device, there are a Phase Change (PC) mode, a Twisted Nematic (TN) mode, a Super Twisted Nematic (STN) mode, a Bistable Twisted Nematic (BTN) mode, an Electrically Controlled Birefringence (ECB) mode, an Optically Compensated Bend (OCB) mode, an in-plane switching (IPS) mode, a Vertical Alignment (VA) mode, a Fringe Field Switching (FFS) mode, a Polymer Stabilized Alignment (PSA) mode, and the like. In the PSA mode element, a liquid crystal composition containing a polymer is used. For the composition, the orientation of the liquid crystal molecules can be controlled using a polymer.

A liquid crystal composition having appropriate physical properties can be used for such a liquid crystal display element. In order to further improve the characteristics of the device, it is preferable that the liquid crystalline compound contained in the composition has the physical properties shown in the following (1) to (8). (1) High stability to heat or light, (2) high clearing point (clearing point), (3) low lower limit temperature of liquid crystal phase, (4) low viscosity (. eta.), (5) appropriate optical anisotropy (. DELTA.n), (6) large dielectric anisotropy (. DELTA.. epsilon.), (7) appropriate elastic constant (K), and (8) good compatibility with other liquid crystal compounds.

The effects of the physical properties of the liquid crystalline compound on the characteristics of the device are as follows. The compound having high stability against heat or light as in (1) improves the voltage holding ratio of the device. Thereby, the life of the element is extended. The compound having a high clearing point as in (2) expands the temperature range of the usable element. The compound having a liquid crystal phase having a nematic phase or a smectic phase as in (3) and having a low lower limit temperature, particularly a low lower limit temperature of a nematic phase, also expands the temperature range in which the element can be used. The compound having a low viscosity as in (4) shortens the response time of the element.

Depending on the design of the element, a compound having appropriate optical anisotropy, that is, large optical anisotropy or small optical anisotropy as in (5) is required. In the case of shortening the response time by reducing the cell gap (cell gap) of the element, a compound having a large optical anisotropy is suitable. The compound having large dielectric anisotropy as in (6) lowers the threshold voltage of the element. This reduces the power consumption of the device. On the other hand, a compound having a small dielectric anisotropy shortens the response time of the element by lowering the viscosity of the composition. The compound expands the temperature range of usable elements by raising the upper limit temperature of the nematic phase.

With regard to (7), the compound having a large elastic constant shortens the response time of the element. Compounds with small elastic constants lower the threshold voltage of the element. Therefore, an appropriate elastic constant is required according to the characteristics to be improved. Preferred is a compound having good compatibility with other liquid crystalline compounds as in (8). The reason for this is that: liquid crystalline compounds having different physical properties are mixed to adjust the physical properties of the composition.

Many liquid crystalline compounds have been synthesized so far. The development of new liquid crystalline compounds is continuing. The reason is that: novel compounds are expected to have good physical properties which are not present in conventional compounds. And the reason is that: sometimes the novel compounds also impart an appropriate balance of at least two physical properties to the composition. Under such circumstances, a compound having good physical properties and an appropriate balance with respect to the physical properties (1) to (8) is desired.

For example, the following compound (PGT-2-1) is described on page 72 of patent document 1.

On page 61 of patent document 2, the following compound 5 is described.

The following compound (PUS-3-2) is described on page 80 of patent document 3, page 69 of patent document 4, page 67 of patent document 5, and page 68 of patent document 6.

[ Prior art documents ]

[ patent document ]

[ patent document 1] International publication No. 2009/129915

[ patent document 2] International publication No. 2010/094455

[ patent document 3] International publication No. 2010/099853

[ patent document 4] International publication No. 2012 and 007096

[ patent document 5] International publication No. 2012/013281

[ patent document 6] International publication No. 2016-146240

Disclosure of Invention

[ problems to be solved by the invention ]

A first object is to provide a liquid crystalline compound that sufficiently satisfies at least one of high stability to heat or light, high clearing point (or high upper limit temperature of nematic phase), low lower limit temperature of liquid crystal phase, low viscosity, appropriate optical anisotropy, large dielectric anisotropy, appropriate elastic constant, and good compatibility with other liquid crystalline compounds. Compared with similar compounds, the compound has high clearing point (or high upper limit temperature of nematic phase) and large dielectric anisotropy. A second object is to provide a liquid crystal composition containing the compound and sufficiently satisfying at least one of the following physical properties such as high stability to heat or light, high upper limit temperature of a nematic phase, low lower limit temperature of the nematic phase, low viscosity, appropriate optical anisotropy, large dielectric anisotropy, large resistivity, and appropriate elastic constant. The subject is to provide a liquid crystal composition having an appropriate balance between at least two physical properties. The third object is to provide a liquid crystal display element which contains the composition and can be used in an element, and has a wide temperature range, a short response time, a high voltage holding ratio, a low threshold voltage, a high contrast ratio, a low flicker rate, and a long life.

[ means for solving problems ]

The present invention relates to a compound represented by formula (1), a liquid crystal composition containing the compound, and a liquid crystal display element including the composition.

In the formula (1), the reaction mixture is,

R¹is hydrogen, P-Sp-, or alkyl with 1 to 15 carbon atoms, and R is¹In (1), at least one-CH₂-may be substituted by-O-, -S-, or-CO-, at least one-CH₂CH₂-may be substituted by-CH ═ CH-or-C ≡ C-, at least one hydrogen may be substituted by fluoro or chloro, but R is¹Is not fluorine or chlorine;

R²is hydrogen, fluorine, chlorine, -C.ident.N, -C.ident.C-C.ident.N, -NCS, -SCN, -SF₅P-Sp-or C1-15 alkyl, R²In (1), at least one-CH₂-may be substituted by-O-, -S-, or-CO-, at least one-CH₂CH₂-may be substituted by-CH ═ CH-or-C ≡ C-, at least one hydrogen may be substituted by fluoro or chloro;

p is a polymerizable group;

sp is a spacer group or a single bond;

ring N¹And ring N²Independently a cycloalkylene group of carbon number 3 to 5, in which at least one-CH group₂-may be substituted by-O-at least one-CH₂CH₂-may be substituted by-CH ═ CH-;

ring A¹And ring A²Independently 1, 4-cyclohexylene, 1, 4-cyclohexenylene, 1, 4-phenylene, naphthalene-2, 6-diyl, 1,2,3, 4-tetrahydronaphthalene-2, 6-diyl, tetrahydropyran-2, 5-diyl, dihydropyran-2, 5-diyl, 1, 3-dioxane-2, 5-diyl, pyridine-2, 5-diyl, or pyrimidine-2, 5-diyl, said ring A being¹And ring A²Wherein at least one hydrogen may be replaced by fluorine, chlorine, -C ≡ N, -CH₃、-CF₃、-CHF₂、-CH₂F、-OCF₃、-OCHF₂or-OCH₂F is substituted;

Z¹、Z²、Z³and Z⁴Independently a single bond or alkylene having 1 to 6 carbon atoms, Z¹、Z²、Z³And Z⁴In (1), at least one-CH₂-may be substituted by-O-, -S-, or-CO-, at least one-CH₂CH₂-may be substituted by-CH ═ CH-or-C ≡ C-, at least one hydrogen may be substituted by fluoro or chloro;

a is 0, 1,2 or 3, b is 0, 1,2 or 3, and c is 0 or 1.

[ Effect of the invention ]

A first advantage is to provide a liquid crystalline compound that sufficiently satisfies at least one of high stability to heat or light, high clearing point (or high upper limit temperature of nematic phase), low lower limit temperature of liquid crystal phase, low viscosity, appropriate optical anisotropy, large dielectric anisotropy, appropriate elastic constant, and good compatibility with other liquid crystalline compounds. Compared with similar compounds, the compound has high clearing point (or high upper limit temperature of nematic phase) and large dielectric anisotropy. A second advantage is to provide a liquid crystal composition containing the compound and sufficiently satisfying at least one of the following properties such as high stability to heat or light, high upper limit temperature of a nematic phase, low lower limit temperature of the nematic phase, low viscosity, appropriate optical anisotropy, large dielectric anisotropy, large resistivity, and appropriate elastic constant. This is advantageous in that a liquid crystal composition having an appropriate balance with respect to at least two physical properties is provided. The third advantage is to provide a liquid crystal display device which contains the composition and can use the device, and has a wide temperature range, a short response time, a large voltage holding ratio, a low threshold voltage, a large contrast ratio, a small flicker rate, and a long life.

Detailed Description

The usage of the terms in the present specification is as follows. The terms "liquid crystalline compound", "liquid crystal composition" and "liquid crystal display element" may be simply referred to as "compound", "composition" and "element", respectively. The "liquid crystalline compound" is a generic name for compounds having a liquid crystal phase such as a nematic phase or a smectic phase and compounds having no liquid crystal phase and added for the purpose of adjusting physical properties of the composition such as an upper limit temperature, a lower limit temperature, viscosity, and dielectric anisotropy. The compound has a six-membered ring such as 1, 4-cyclohexylene or 1, 4-phenylene, and its molecular structure is rod-like (rod like). The term "liquid crystal display element" is a generic term for liquid crystal display panels and liquid crystal display modules. The "polymerizable compound" is a compound added for the purpose of producing a polymer in the composition. The liquid crystalline compound having an alkenyl group is not polymerizable in the meaning.

The liquid crystal composition is prepared by mixing a plurality of liquid crystalline compounds. Additives are added to the composition for the purpose of further adjusting physical properties. If necessary, additives such as a polymerizable compound, a polymerization initiator, a polymerization inhibitor, an optically active compound, an antioxidant, an ultraviolet absorber, a light stabilizer, a heat stabilizer, a pigment, and an antifoaming agent are added. The liquid crystalline compound or the additive is mixed in this order. Even in the case where an additive is added, the proportion (content) of the liquid crystalline compound is represented by a weight percentage (wt%) based on the weight of the liquid crystal composition containing no additive. The proportion (addition amount) of the additive is represented by a weight percentage (% by weight) based on the weight of the liquid crystal composition containing no additive. That is, the ratio of the liquid crystalline compound or the additive is calculated based on the total weight of the liquid crystalline compound. Parts per million (ppm) by weight are also sometimes used. The proportions of the polymerization initiator and the polymerization inhibitor are exceptionally expressed based on the weight of the polymerizable compound.

The "clearing point" is a transition temperature of a liquid crystal phase-isotropic phase of a liquid crystalline compound. The "lower limit temperature of the liquid crystal phase" is a transition temperature of a solid-liquid crystal phase (smectic phase, nematic phase, etc.) of the liquid crystalline compound. The "upper limit temperature of the nematic phase" is a transition temperature of a mixture of a liquid crystalline compound and a mother liquid crystal or a nematic phase-isotropic phase of a liquid crystal composition, and may be simply referred to as "upper limit temperature". The "lower limit temperature of the nematic phase" may be simply referred to as "lower limit temperature". The expression "to improve the dielectric anisotropy" means that the value thereof increases positively in the case of a composition having a positive dielectric anisotropy and increases negatively in the case of a composition having a negative dielectric anisotropy. The term "high voltage holding ratio" means that the device has a large voltage holding ratio not only at room temperature but also at a temperature close to the upper limit temperature in the initial stage, and also has a large voltage holding ratio not only at room temperature but also at a temperature close to the upper limit temperature after long-term use. In some cases, the properties of the composition or the device are examined before and after a time-dependent change test (including an accelerated deterioration test).

The compound represented by formula (1) may be simply referred to as compound (1). Sometimes selected from the compounds represented by the formula (1)At least one compound of the group (2) is abbreviated as compound (1). The "compound (1)" means one compound, a mixture of two compounds or a mixture of three or more compounds represented by the formula (1). These rules apply to compounds represented by other formulae. In the formulae (1) to (15), A is surrounded by a hexagon¹、B¹、C¹The marks respectively corresponding to the rings A¹Ring B¹Ring C¹And (3) waiting for a ring. The hexagon represents a six-membered ring like cyclohexane or benzene. The hexagon sometimes represents a condensed ring like naphthalene or a crosslinked ring like adamantane.

In the chemical formula of the component compound, the terminal group R¹¹The notation of (a) is used for a variety of compounds. In these compounds, any two R¹¹The two radicals indicated may be identical or else different. For example, R of the compound (2)¹¹Is ethyl, and R of the compound (3)¹¹In the case of ethyl. Also R of the compound (2)¹¹Is ethyl, and R of the compound (3)¹¹In the case of propyl. This rule also applies to R¹²、R¹³、Z¹¹And the like. In the compound (8), when i is 2, two rings D are present¹. In the compounds, two rings D¹The two radicals indicated may be identical or may also be different. When i is greater than 2, the same applies to any two rings D¹. This rule also applies to other tokens.

The expression "at least one 'a' means that the number of 'a's is arbitrary. The expression "at least one 'a' may be substituted with 'B' means that when the number of 'a' is one, the position of 'a' is arbitrary, and when the number of 'a' is two or more, the positions of these may also be selected without limitation. This rule also applies to the expression "at least one 'a' is substituted with 'B'. The expression "at least one 'a' may be substituted with 'B', 'C' or 'D' is meant to include any substitution of 'a' with 'B', any substitution of 'a' with 'C' and any substitution of 'a' with 'D', further including the substitution of a plurality of at least two of 'a' with 'B', 'C' and/or 'D'. For example, "at least one-CH₂Examples of the "alkyl group which may be substituted by — O-or-CH ═ CH-include alkyl, alkoxy, alkoxyalkyl, alkenyl, alkoxyalkenyl, and alkenyloxyalkyl. In addition, two-CHs in succession₂The case where-O-is substituted to be-O-is not preferable. Alkyl, etc., methyl moiety (-CH)₂-CH of- (O-H)₂The case where-O-is substituted with-O-to form-O-H is also not preferred.

Sometimes using "R¹¹And R¹²Independently an alkyl group having 1 to 10 carbon atoms or an alkenyl group having 2 to 10 carbon atoms, at least one-CH group being present in the alkyl group or the alkenyl group₂-may be substituted by-O-, and of these groups at least one hydrogen may be substituted by fluorine ". In this expression, "in these groups" can be interpreted in a sentence meaning. In this expression, "these groups" means alkyl groups, alkenyl groups, alkoxy groups, alkenyloxy groups, and the like. That is, "these groups" means all the groups described before the term "in these groups". This common sense interpretation also applies to the terms "in these monovalent radicals" or "in these divalent radicals". For example, "these monovalent groups" means all the groups described before the expression "in" these monovalent groups.

Halogen means fluorine, chlorine, bromine, and iodine. Preferred halogens are fluorine and chlorine. Further preferred halogen is fluorine. The alkyl group of the liquid crystalline compound is linear or branched and does not contain a cyclic alkyl group. Cycloalkyl refers to cyclic alkyl. Straight chain alkyls are generally preferred over branched alkyls. The same applies to the terminal group such as an alkoxy group or an alkenyl group. For the configuration (configuration) related to the 1, 4-cyclohexylene group, the trans form is preferred to the cis form in order to increase the upper limit temperature. 2-fluoro-1, 4-phenylene refers to the following two divalent radicals. In the formula, fluorine may be either to the left (L) or to the right (R). This rule also applies to unsymmetrical divalent radicals generated by ring removal of two hydrogens, such as tetrahydropyran-2, 5-diyl. Straight chain alkyls are generally preferred over branched alkyls. The same applies to the terminal group such as an alkoxy group or an alkenyl group. For the configuration (configuration) related to the 1, 4-cyclohexylene group, the trans form is preferred to the cis form in order to increase the upper limit temperature. 2-fluoro-1, 4-phenylene refers to the following two divalent radicals. In the formula, fluorine may be either to the left (L) or to the right (R). This rule also applies to unsymmetrical divalent radicals generated by ring removal of two hydrogens, such as tetrahydropyran-2, 5-diyl.

The present invention is as follows.

Item 1. a compound represented by formula (1).

In the formula (1), the reaction mixture is,

p is a polymerizable group;

sp is a spacer group or a single bond;

ring A¹And ring A²Independently 1, 4-cyclohexylene, 1, 4-cyclohexenylene, 1, 4-phenylene, naphthalene-2, 6-diyl, 1,2,3, 4-tetrahydronaphthalene-2, 6-diyl, tetrahydropyran-2, 5-diyl, dihydropyran-2, 5-diyl, 1, 3-dioxane-2, 5-diyl, pyridine-2, 5-diyl,Or pyrimidine-2, 5-diyl, said ring A¹And ring A²Wherein at least one hydrogen may be replaced by fluorine, chlorine, -C ≡ N, -CH₃、-CF₃、-CHF₂、-CH₂F、-OCF₃、-OCHF₂or-OCH₂F is substituted;

a is 0, 1,2 or 3, b is 0, 1,2 or 3, and c is 0 or 1.

Item 2. the compound according to item 1, represented by formula (1 a).

In the formula (1a), the compound (A),

R²is fluorine, chlorine, -C.ident.N, -C.ident.C-C.ident.N, -NCS, -SCN, -SF-N₅P-Sp-, or C1-15 alkyl, said R²In (1), at least one-CH₂-may be substituted by-O-, -S-, or-CO-, at least one-CH₂CH₂-may be substituted by-CH ═ CH-or-C ≡ C-, at least one hydrogen may be substituted by fluoro or chloro;

p is a polymerizable group;

sp is a spacer group or a single bond;

ring N¹Is cycloalkylene having a carbon number of 3 to 5, the ring N¹In (1), at least one-CH₂-may be substituted by-O-at least one-CH₂CH₂-may be substituted by-CH ═ CH-;

Z¹、Z²and Z³Independently a single bond or alkylene having 1 to 6 carbon atoms, Z¹、Z²And Z³In (1), at least one-CH₂-may be substituted by-O-, -S-, or-CO-, at least one-CH₂CH₂-may be substituted by-CH ═ CH-or-C ≡ C-, at least one hydrogen may be substituted by fluoro or chloro;

a is 0, 1,2 or 3, and b is 0, 1,2 or 3.

The compound according to item 1 or item 2, represented by any one of formula (1-1) to formula (1-10).

In the formulae (1-1) to (1-10),

R¹is hydrogen or alkyl with 1 to 15 carbon atoms, the R¹In (1), at least one-CH₂-may be substituted by-O-, -S-, or-CO-, at least one-CH₂CH₂-may be substituted by-CH ═ CH-or-C ≡ C-, at least one hydrogen may be substituted by fluoro or chloro, but R is¹Is not fluorine or chlorine;

R²is fluorine, chlorine, -C.ident.N, -C.ident.C-C.ident.N, -NCS, -SCN, -SF-N₅Or an alkyl group having 1 to 15 carbon atoms, R²In (1), at least one-CH₂-may be substituted by-O-, -S-, or-CO-, at least one-CH₂CH₂-may be substituted by-CH ═ CH-or-C ≡ C-, at least one hydrogen may be substitutedSubstituted by fluorine or chlorine;

ring A¹And ring A²Independently 1, 4-cyclohexylene, 1, 4-cyclohexenylene, 1, 4-phenylene, naphthalene-2, 6-diyl, tetrahydropyran-2, 5-diyl, 1, 3-dioxan-2, 5-diyl, pyridine-2, 5-diyl, or pyrimidine-2, 5-diyl, said ring A¹And ring A²Wherein at least one hydrogen may be replaced by fluorine, chlorine, -C ≡ N, -CH₃、-CF₃、-CHF₂、-CH₂F、-OCF₃、-OCHF₂or-OCH₂F is substituted;

Z¹、Z²and Z³Independently a single bond or alkylene having 1 to 6 carbon atoms, Z¹、Z²And Z³In (1), at least one-CH₂-may be substituted by-O-, -S-, or-CO-, at least one-CH₂CH₂-may be substituted by-CH ═ CH-or-C ≡ C-, at least one hydrogen may be substituted by fluoro or chloro.

Item 4. the compound according to item 3, wherein, in the formulae (1-1) to (1-10),

R¹is hydrogen, alkyl group having 1 to 15 carbon atoms, alkoxy group having 1 to 14 carbon atoms, alkoxyalkyl group having 2 to 14 carbon atoms, alkenyl group having 2 to 15 carbon atoms, or alkenyloxy group having 2 to 14 carbon atoms;

R²is fluorine, chlorine, -CF₃、-OCF₃-C ≡ N, an alkyl group having 1 to 15 carbon atoms, an alkoxy group having 1 to 14 carbon atoms, an alkoxyalkyl group having 2 to 14 carbon atoms, an alkenyl group having 2 to 15 carbon atoms, or an alkenyloxy group having 2 to 14 carbon atoms;

ring N¹Is 1, 2-cyclopropylene, 1, 3-cyclobutylene, or 1, 3-cyclopentylene;

ring A¹And ring A²Independently 1, 4-cyclohexylene, 1, 4-cyclohexenylene, 1, 4-phenylene, tetrahydropyran-2, 5-diyl, 1, 3-dioxan-2, 5-diyl, pyridine-2, 5-diyl, or pyrimidine-2, 5-diyl, wherein at least one of the bivalent groups may be substituted with fluorine, chlorine, fluorine, or fluorineC≡N、-CH₃、-CF₃、-CHF₂、-CH₂F、-OCF₃、-OCHF₂or-OCH₂F is substituted;

Z¹、Z²and Z³Independently a single bond, -O-, -CH₂-、-CO-、-COO-、-OCO-、-CH₂O-、-OCH₂-、-CF₂O-、-OCF₂-、-CH₂CH₂-、-CH＝CH-、-CF＝CH-、-CH＝CF-、-CF＝CF-、-C≡C-、-(CH₂)₄-、-(CH₂)₂COO-、-(CH₂)₂OCO-、-OCO(CH₂)₂-、-COO(CH₂)₂-、-(CH₂)₂CF₂O-、-(CH₂)₂OCF₂-、-OCF₂(CH₂)₂-、-CF₂O(CH₂)₂-、-(CH₂)₃O-、-O(CH₂)₃-、-CH＝CH-(CH₂)₂-、-(CH₂)₂-CH＝CH-、-CH＝CH-CH₂O-, or-OCH₂-CH＝CH-。

Item 5. the compound according to any one of item 1 to item 4, represented by any one of formula (1-1-1), formula (1-2-1), formula (1-3-1), formula (1-4-1), formula (1-5-1), formula (1-6-1), formula (1-7-1), formula (1-8-2), formula (1-9-1), formula (1-9-2), formula (1-10-1), or formula (1-10-2).

In the formula (1-1-1), the formula (1-2-1), the formula (1-3-1), the formula (1-4-1), the formula (1-5-1), the formula (1-6-1), the formula (1-7-1), the formula (1-8-2), the formula (1-9-1), the formula (1-9-2), the formula (1-10-1) and the formula (1-10-2),

R¹is hydrogen, alkyl group having 1 to 15 carbon atoms, alkoxy group having 1 to 14 carbon atoms, alkoxy group having 2 to 14 carbon atomsAn alkoxyalkyl group having 14 carbon atoms, an alkenyl group having 2 to 15 carbon atoms, or an alkenyloxy group having 2 to 14 carbon atoms;

ring N¹Is 1, 2-cyclopropylene, 1, 3-cyclobutylene, or 1, 3-cyclopentylene;

ring A¹And ring A²Independently 1, 4-cyclohexylene, 1, 4-cyclohexenylene, 1, 4-phenylene, tetrahydropyran-2, 5-diyl, 1, 3-dioxan-2, 5-diyl, pyridine-2, 5-diyl, or pyrimidine-2, 5-diyl, wherein at least one hydrogen in the divalent radicals may be replaced by fluorine, chlorine, -C.ident.N, -CH₃、-CF₃、-CHF₂、-CH₂F、-OCF₃、-OCHF₂or-OCH₂F is substituted;

Item 6. the compound according to item 5, wherein in the formula (1-1-1), the formula (1-2-1), the formula (1-3-1), the formula (1-4-1), the formula (1-5-1), the formula (1-6-1), the formula (1-7-1), the formula (1-8-2), the formula (1-9-1), the formula (1-9-2), the formula (1-10-1), or the formula (1-10-2),

R¹is hydrogen, alkyl group having 1 to 10 carbon atoms, alkoxy group having 1 to 9 carbon atoms, alkoxyalkyl group having 2 to 9 carbon atoms, alkenyl group having 2 to 10 carbon atoms, or alkenyloxy group having 2 to 9 carbon atoms;

R²is fluorine, -CF₃、-OCF₃-C ≡ N, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 9 carbon atoms, an alkoxyalkyl group having 2 to 9 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, or an alkenyloxy group having 2 to 9 carbon atoms;

ring N¹Is 1, 2-cyclopropylene, 1, 3-cyclobutylene, or 1, 3-cyclopentylene;

ring A¹And ring A²Independently 1, 4-cyclohexylene, 1, 4-cyclohexenylene, 1, 4-phenylene, tetrahydropyran-2, 5-diyl, or 1, 3-dioxan-2, 5-diyl, wherein at least one hydrogen may be replaced by fluorine, chlorine, -C.ident.N, -CH₃、-CF₃、-CHF₂、-CH₂F、-OCF₃、-OCHF₂or-OCH₂F is substituted;

Z¹、Z²and Z³Independently a single bond, -O-, -CH₂-、-CO-、-COO-、-OCO-、-CH₂O-、-OCH₂-、-CF₂O-、-OCF₂-、-CH₂CH₂-、-CH＝CH-、-C≡C-、-(CH₂)₄-、-(CH₂)₃O-、-O(CH₂)₃-、-CH＝CH-(CH₂)₂-、-(CH₂)₂-CH＝CH-、-CH＝CH-CH₂O-, or-OCH₂-CH＝CH-。

Item 7. the compound according to any one of items 1 to 6, represented by formula (1-2-1-1), formula (1-3-1-1) to formula (1-3-1-6), or formula (1-4-1-1) to formula (1-4-1-18).

In the formula (1-2-1-1), the formulae (1-3-1-1) to (1-3-1-6), and the formulae (1-4-1-1) to (1-4-1-18),

ring N¹Is 1, 2-cyclopropylene, 1, 3-cyclobutylene, or 1, 3-cyclopentylene;

Z¹is a single bond, -O-, -CH₂-、-CO-、-COO-、-OCO-、-CH₂O-、-OCH₂-、-CF₂O-、-OCF₂-、-CH₂CH₂-、-CH＝CH-、-(CH₂)₄-、-(CH₂)₃O-、-O(CH₂)₃-、-CH＝CH-(CH₂)₂-、-(CH₂)₂-CH＝CH-、-CH＝CH-CH₂O-, or-OCH₂-CH＝CH-。

Item 8 the compound according to item 7, wherein in the formula (1-2-1-1), the formula (1-3-1-1) to the formula (1-3-1-6), or the formula (1-4-1-1) to the formula (1-4-1-18),

R¹is hydrogen, alkyl group having 1 to 6 carbon atoms, alkoxy group having 1 to 5 carbon atoms, alkoxyalkyl group having 2 to 5 carbon atoms, alkenyl group having 2 to 6 carbon atoms, or alkenyloxy group having 2 to 5 carbon atoms;

R²is fluorine, -OCF₃-C ≡ N, alkyl group having 1 to 6 carbon atoms, alkoxy group having 1 to 5 carbon atoms, alkoxyalkyl group having 2 to 5 carbon atoms, alkenyl group having 2 to 6 carbon atoms, orAn alkenyloxy group having a carbon number of 2 to 5;

ring N¹Is 1, 2-cyclopropylene, 1, 3-cyclobutylene, or 1, 3-cyclopentylene;

Z¹is a single bond, -O-, -CH₂-、-CO-、-COO-、-OCO-、-CH₂O-、-OCH₂-、-CF₂O-、-OCF₂-、-CH₂CH₂-, or-CH ═ CH-.

A liquid crystal composition comprising at least one compound according to any one of items 1 to 8.

Item 10. the liquid crystal composition according to item 9, further comprising at least one compound selected from the group of compounds represented by formulae (2) to (4).

In the formulae (2) to (4),

R¹¹and R¹²Independently an alkyl group having a carbon number of 1 to 10 or an alkenyl group having a carbon number of 2 to 10, R¹¹And R¹²In (1), at least one-CH₂-may be substituted by-O-, at least one hydrogen may be substituted by fluorine;

ring B¹Ring B²Ring B³And ring B⁴Independently 1, 4-cyclohexylene, 1, 4-phenylene, 2-fluoro-1, 4-phenylene, 2, 5-difluoro-1, 4-phenylene, or pyrimidin-2, 5-diyl;

Z¹¹、Z¹²and Z¹³Independently a single bond, -COO-, -CH₂CH₂-, -CH ═ CH-, or-C ≡ C-.

Item 11. the liquid crystal composition according to item 9 or item 10, further comprising at least one compound selected from the group of compounds represented by formulae (5) to (7).

In the formulae (5) to (7),

R¹³is alkyl with 1 to 10 carbon atoms or alkenyl with 2 to 10 carbon atoms, and R is¹³In (1), at least one-CH₂-may be substituted by-O-, at least one hydrogen may be substituted by fluorine;

X¹¹is fluorine, chlorine, -OCF₃、-OCHF₂、-CF₃、-CHF₂、-CH₂F、-OCF₂CHF₂or-OCF₂CHFCF₃；

Ring C¹Ring C²And ring C³Independently 1, 4-cyclohexylene, 1, 4-phenylene in which at least one hydrogen is substituted by fluorine, tetrahydropyran-2, 5-diyl, 1, 3-dioxan-2, 5-diyl, or pyrimidine-2, 5-diyl;

Z¹⁴、Z¹⁵and Z¹⁶Independently a single bond, -COO-, -OCO-, -CH₂O-、-OCH₂-、-CF₂O-、-OCF₂-、-CH₂CH₂-, -CH ═ CH-, -C ≡ C-, or- (CH)₂)₄-；

L¹¹And L¹²Independently hydrogen or fluorine.

Item 12. the liquid crystal composition according to any one of item 9 to item 11, further comprising at least one compound selected from the group of compounds represented by formula (8).

In the formula (8), the reaction mixture is,

R¹⁴is alkyl with 1 to 10 carbon atoms or alkenyl with 2 to 10 carbon atoms, and R is¹⁴In (1), at least one-CH₂-may be substituted by-O-, at least one hydrogen may be substituted by fluorine;

X¹²is-C.ident.N or-C.ident.C-C.ident.N;

ring D¹Is 1, 4-cyclohexylene, 1, 4-phenylene in which at least one hydrogen is substituted by fluorine, tetrahydropyran-2, 5-diyl, 1, 3-dioxan-2, 5-diyl or pyrimidine-2, 5-diyl;

Z¹⁷is a single bond, -COO-, -OCO-, -CH₂O-、-OCH₂-、-CF₂O-、-OCF₂-、-CH₂CH₂-, or-C.ident.C-;

L¹³and L¹⁴Independently hydrogen or fluorine;

i is 1,2,3, or 4.

Item 13. the liquid crystal composition according to any one of items 9 to 12, further comprising at least one compound selected from the group of compounds represented by formulae (11) to (19).

In the formulae (11) to (19),

R¹⁵、R¹⁶and R¹⁷Independently an alkyl group having a carbon number of 1 to 10 or an alkenyl group having a carbon number of 2 to 10, R¹⁵、R¹⁶And R¹⁷In (1), at least one-CH₂-may be substituted by-O-, at least one hydrogen may be substituted by fluorine, and, R¹⁷Can be hydrogen or fluorine;

ring E¹Ring E²Ring E³And ring E⁴Independently 1, 4-cyclohexylene, 1, 4-cyclohexenylene, 1, 4-phenylene in which at least one hydrogen is substituted with fluorine, tetrahydropyran-2, 5-diyl, or decahydronaphthalene-2, 6-diyl;

ring E⁵And ring E⁶Independently 1, 4-cyclohexylene, 1, 4-cyclohexenylene, 1, 4-phenylene, tetrahydropyran-2, 5-diyl, or decahydronaphthalene-2, 6-diyl;

Z¹⁸、Z¹⁹、Z²⁰and Z²¹Independently a single bond, -COO-, -OCO-, -CH₂O-、-OCH₂-、-CF₂O-、-OCF₂-、-CH₂CH₂-、-CF₂OCH₂CH₂-, or-OCF₂CH₂CH₂-；

L¹⁵And L¹⁶Independently fluorine or chlorine;

S¹¹is hydrogen or methyl;

x is-CHF-or-CF₂-；

j. k, m, n, p, q, r, and s are independently 0 or 1, the sum of k, m, n, and p is 1 or 2, the sum of q, r, and s is 0, 1,2, or 3, and t is 1,2, or 3.

Item 14. a liquid crystal display element comprising the liquid crystal composition according to any one of item 9 to item 13.

The present invention also includes the following items. (a) The composition further contains one, two or at least three additives selected from the group consisting of a polymerizable compound, a polymerization initiator, a polymerization inhibitor, an optically active compound, an antioxidant, an ultraviolet absorber, a light stabilizer, a heat stabilizer, a pigment and an antifoaming agent. (b) The liquid crystal composition has an upper limit temperature of a nematic phase of 70 ℃ or higher, an optical anisotropy (measured at 25 ℃) of 0.07 or higher at a wavelength of 589nm, and a dielectric anisotropy (measured at 25 ℃) of 2 or higher at a frequency of 1 kHz. (c) The liquid crystal display element has an operation mode of a TN mode, an ECB mode, an OCB mode, an IPS mode, a VA mode, an FFS mode, or a field-induced photo-alignment (FPA) mode, and is driven by an Active Matrix (AM) mode.

The form of compound (1), the synthesis method of compound (1), the liquid crystal composition, and the liquid crystal display element will be described in order.

1. Forms of Compound (1)

The compound (1) of the present invention has a structure of a thiophene ring and a three-membered, four-membered or five-membered ring. Compound (1) is characterized in that: in comparison with the similar compound, the clearing point was high (or the upper limit temperature of the nematic phase was high), and the dielectric anisotropy was large (see comparative example 1). Preferred examples of the compound (1) will be described. Terminal group R in Compound (1)¹And the terminal group R²P, Sp, Ring N¹Ring N²Ring A¹And ring A²A bonding group Z¹A bonding group Z²A bonding group Z³And a bonding group Z⁴Preferred examples of a, b and c also apply to the compound (1) belowBit type. In the compound (1), the physical properties can be arbitrarily adjusted by appropriately combining these groups. Since there is no great difference in physical properties of the compounds, the compound (1) may be contained in an amount larger than that of the naturally occurring compound²H (deuterium),¹³C is an isotope. Further, the symbol of the compound (1) is defined as described in the item 1.

In the formula (1), the reaction mixture is,

R¹is hydrogen, P-Sp-, or alkyl with 1 to 15 carbon atoms, and R is¹In (1), at least one-CH₂-may be substituted by-O-, -S-, or-CO-, at least one-CH₂CH₂-may be substituted by-CH ═ CH-or-C ≡ C-, at least one hydrogen may be substituted by fluoro or chloro, but R is¹Not fluorine or chlorine.

R²Is hydrogen, fluorine, chlorine, -C.ident.N, -C.ident.C-C.ident.N, -NCS, -SCN, -SF₅P-Sp-or C1-15 alkyl, R²In (1), at least one-CH₂-may be substituted by-O-, -S-, or-CO-, at least one-CH₂CH₂-may be substituted by-CH ═ CH-or-C ≡ C-, at least one hydrogen may be substituted by fluoro or chloro.

Preferred R¹Or R²Is hydrogen, P-Sp-, alkyl, alkoxy, alkoxyalkyl, alkoxyalkoxy, alkenyl, alkenyloxy, alkenyloxyalkyl, alkoxyalkenyl, alkylthio, alkylthioalkyl, alkenylthio, alkenylthioalkyl, alkylthioalkenyl, acyl, acylalkyl, acyloxy, acyloxyalkyl, alkoxycarbonyl, alkynyl, and alkynyloxy. Of these groups, at least one hydrogen may be substituted by fluorine or chlorine. The examples include groups in which at least two hydrogens are substituted with both fluorine and chlorine. Among these groups, straight chain is preferable to branched chain. R¹Or R²Even if it is a branched chain, it is preferable when it is optically active. In addition to being able to be these radicals, R²Can also be fluorine, chlorine, -C.ident.N, -C.ident.C-C.ident.N, -NCS, -SCN, and-SF₅. Further preferred is R¹Or R²Is alkyl or alkoxyA group, alkoxyalkyl, alkoxyalkoxy, alkenyl, alkenyloxy, alkenyloxyalkyl, or alkoxyalkenyl. In addition to being able to be these radicals, R²Fluorine, chlorine, -C.ident.N, -C.ident.C-C.ident.N, and-NCS. Especially preferred R¹Or R²Is alkyl, alkoxy, alkoxyalkyl, alkenyl, or alkenyloxy. In addition to being able to be these radicals, R²Fluorine, chlorine, and-C.ident.N may also be mentioned.

Specific R¹Or R²Is methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, methoxy, ethoxy, propoxy, butoxy, pentoxy, hexoxy, heptoxy, methoxymethyl, methoxyethyl, methoxypropyl, ethoxymethyl, ethoxyethyl, ethoxypropyl, propoxymethyl, propoxyethyl, butoxymethyl, butoxyethyl, pentoxymethyl, pentoxyethyl, ethenyl, 1-propenyl, 2-propenyl, 1-butenyl, 2-butenyl, 3-butenyl, 1-pentenyl, 2-pentenyl, 3-pentenyl, 4-pentenyl, 1-hexenyl, 2-hexenyl, 3-hexenyl, 4-hexenyl, 5-hexenyl, 1-heptenyl, 2-heptenyl, 3-heptenyl, 4-heptenyl, 5-heptenyl, 6-heptenyl, 2-propenyloxy, 2-butenyloxy, 2-pentenyloxy, 2-hexenyloxy, 1-propynyl, and 1-butynyl.

Specific R¹Or R²Also, 2-fluoroethyl, 3-fluoropropyl, 2,2, 2-trifluoroethyl, 2-fluorovinyl, 2, 2-difluorovinyl, 2-fluoro-2-vinyl, 3-fluoro-1-propenyl, 3,3, 3-trifluoro-1-propenyl, 4-fluoro-1-propenyl, and 4, 4-difluoro-3-butenyl.

Specific R²Is fluorine, chlorine, -C.ident.N, -C.ident.C-C.ident.N, -NCS, -SCN, -SF-N₅、-CF₃、-CHF₂、-CH₂F、-OCF₃、-OCHF₂、-OCH₂F、-CF₂CF₃、-CF₂CHF₂、-CF₂CH₂F、-CF₂CF₂CF₃、-CF₂CHFCF₃、-CHFCF₂CF₃、-OCF₃、-OCHF₂、-OCH₂F、-OCF₂CF₃、-OCF₂CHF₂、-OCF₂CH₂F、-OCF₂CF₂CF₃、-OCF₂CHFCF₃and-OCHFCF₂CF₃。

Further preferred is R¹Or R²Is methyl, ethyl, propyl, butyl, pentyl, hexyl, methoxy, ethoxy, propoxy, butoxy, pentoxy, methoxymethyl, ethoxymethyl, ethoxyethyl, propoxymethyl, propoxyethyl, butoxymethyl, pentoxymethyl, vinyl, 1-propenyl, 2-propenyl, 1-butenyl, 2-butenyl, 3-butenyl, 1-pentenyl, 2-pentenyl, 3-pentenyl, 4-pentenyl, 1-hexenyl, 2-hexenyl, 3-hexenyl, 4-hexenyl, 5-hexenyl, 2-propenyloxy, 2-butenyloxy, 2-pentenyloxy. In addition, R is more preferable²Is fluorine, chlorine, -C.ident.N, -C.ident.C-C.ident.N, -NCS, -CF ≡ N₃、-CHF₂、-CH₂F、-OCF₃、-OCHF₂、-OCH₂F、-CF₂CF₃、-CF₂CHF₂、-CF₂CH₂F、-OCF₃、-OCHF₂、-OCH₂F、-OCF₂CF₃、-OCF₂CHF₂and-OCF₂CH₂F. Most preferred R¹Or R²Is methyl, ethyl, propyl, butyl, pentyl, hexyl, methoxy, ethoxy, propoxy, butoxy, pentoxy, methoxymethyl, ethoxymethyl, propoxymethyl, butoxymethyl, ethenyl, 1-propenyl, 3-butenyl, 3-pentenyl. In addition, the most preferred R²Is fluorine, chlorine, -C ≡ N, -CF₃、-CHF₂、-CH₂F、-OCF₃、-OCHF₂and-OCH₂F。

When R is¹When the polymer is a linear chain, the liquid crystal phase has a wide temperature range and a low viscosity. When R is¹When the side chain is branched, the compatibility with other liquid crystalline compounds is good. R¹The optically active compound is effective as a chiral dopant (chiral dopant). By adding this compound toIn the composition, reverse twisted domain (reversed twisted domain) generated in the liquid crystal display element can be prevented. R¹Compounds that are not optically active are effective as ingredients of the composition. When R is¹In the case of alkenyl, the preferred configuration depends on the position of the double bond. The alkenyl compound having a preferred steric configuration has a low viscosity, a high upper limit temperature, or a wide temperature range of a liquid crystal phase.

The preferred steric configuration of-CH ═ CH-in the alkenyl group depends on the position of the double bond. Such as-CH ═ CHCH₃、-CH＝CHC₂H₅、-CH＝CHC₃H₇、-CH＝CHC₄H₉、-C₂H₄CH＝CHCH₃and-C₂H₄CH＝CHC₂H₅Among the alkenyl groups having a double bond in the odd-numbered positions in general, the trans configuration is preferred. Such as-CH₂CH＝CHCH₃、-CH₂CH＝CHC₂H₅and-CH₂CH＝CHC₃H₇Among the alkenyl groups having a double bond at the even number position in general, the cis configuration is preferred. The alkenyl compound having a preferred steric configuration has a high clearing point or a wide temperature range of a liquid crystal phase. Detailed descriptions are given in mol. crystal.liq. crystal. (1985, 131, 109) and mol. crystal.liq. crystal. (1985, 131, 327).

In the formula (1), the reaction mixture is,

p is a polymerizable group;

sp is a spacer group or a single bond.

The polymerizable group P is a group suitable for a polymerization reaction such as radical or ionic chain polymerization, addition polymerization, or polycondensation, or a polymer-like reaction, for example, addition or condensation to the main chain. Particularly preferred are groups for chain polymerization, especially groups containing a C ═ C double bond or a C ≡ C triple bond, and groups suitable for ring-opening polymerization such as oxetane or epoxide groups.

Preferred radicals P are selected from CH₂＝CW¹-COO-、CH₂＝CW¹-CO-、

CH₂＝CW²-(O)_k3-、CH₃-CH＝CH-O-、(CH₂＝CH)₂CH-OCO-、(CH₂＝CH-CH₂)₂CH-OCO-、(CH₂＝CH)₂CH-O-、(CH₂＝CH-CH₂)₂N-、(CH₂＝CH-CH₂)₂N-CO-、HO-CW²W³-、HS-CW²W³-、HW²N-、HO-CW²W³-NH-、CH₂＝CW¹-CO-NH-、CH₂＝CH-(COO)_k1-Phe-(O)_k2-、CH₂＝CH-(CO)_k1-Phe-(O)_k2-, Phe-CH ═ CH-, HOOC-, OCN-and W⁴W⁵W⁶Si-, in the formula, W¹Represents H, F, Cl, CN, CF₃Phenyl or alkyl having 1 to 5C atoms, in particular H, F, Cl or CH₃，W²And W³Each independently of the other represents H or an alkyl group having 1 to 5C atoms, in particular H, methyl, ethyl or n-propyl, W⁴、W⁵And W⁶Each independently represents Cl, an oxaalkyl or oxacarbonylalkyl group having 1 to 5C atoms, W⁷And W⁸Each independently of the other represents H, Cl, an alkyl radical having 1 to 5C atoms, Phe represents a 1, 4-phenylene radical which may be substituted by one or more radicals L as defined above, k1, k2 and k3 each independently of the other represent 0 or 1, and k3 preferably represents 1.

Particularly preferred radicals P are CH₂＝CW¹-COO-, especially CH₂＝CH-COO-、CH₂＝C(CH₃) -COO-and CH₂CF-COO-, and further CH₂＝CH-O-、(CH₂＝CH)₂CH-OCO-、(CH₂＝CH)₂CH-O-、

Particularly very preferred radicals P are vinyloxy, acrylate, methacrylate, fluoroacrylate, chloroacrylate, oxetane and epoxide.

The "spacer" described as "Sp" in the specification of the present application is known to those skilled in the art and is described in the literature, for example, in Pure and Applied Chemistry (Pure appl. chem.) book 73 (No. 5), page 888 (2001) and c.zilseske (c.tschieske), g.peltz (g.pelzl), s.diele (s.diele), german Applied Chemistry (angeldown. chemi, angelw.chem.) (2004), volumes 116, pages 6340 to 6368. The term "spacer" or "spacer" as used hereinabove and hereinbelow means a flexible group that connects a mesogen and a polymerizable group(s) to each other in a polymerizable liquid crystal or mesogen compound, unless otherwise specified.

Preferably, the spacer group Sp is a single bond, selected from the formula Sp '-X' in such a way that the group P-Sp corresponds to the formula P-Sp '-X',

sp' represents an alkylene group having 1 to 20, preferably 1 to 12C atoms, which may be mono-or polysubstituted with F, Cl, Br, I or CN, but in addition to this, one or more non-adjacent CH groups₂The radicals may also independently of one another be-O-, -S-, -NH-, -NR⁰-、-SiR⁰⁰R⁰⁰⁰-、-CO-、-COO-、-OCO-、-OCO-O-、-S-CO-、-CO-S-、-NR⁰⁰-CO-O-、-O-CO-NR⁰⁰-、-NR⁰⁰-CO-NR⁰⁰-, -CH-or-C.ident.C-in such a way that the O atoms and/or the S atoms are not linked directly to one another,

x' represents-O-, -S-, -CO-, -COO-, -OCO-, -O-COO-, -CO-NR⁰⁰-、-NR⁰⁰-CO-、-NR⁰⁰-CO-NR⁰⁰-、-OCH₂-、-CH₂O-、-SCH₂-、-CH₂S-、-CF₂O-、-OCF₂-、-CF₂S-、-SCF₂-、-CF₂CH₂-、-CH₂CF₂-、-CF₂CF₂-、-CH＝N-、-N＝CH-、-N＝N-、-CH＝CR⁰-、-CY²＝CY³-、-C.ident.C-, -CH-COO-, -OCO-CH-or a single bond,

R⁰、R⁰⁰and R⁰⁰⁰Each independently of the other represents H or an alkyl group having 1 to 12C atoms, and

Y²and Y³H, F, Cl or CN, respectively, independently of each other.

X' is preferably-O-, -S-, -CO-, -COO-, -OCO-, -O-COO-, -CO-NR-⁰-、-NR⁰-CO-、-NR⁰-CO-NR⁰-or a single bond.

A typical spacer Sp' is, for example, - (CH)₂)_p1-、-(CH₂CH₂O)_q1-CH₂CH₂-、-CH₂CH₂-S-CH₂CH₂-、-CH₂CH₂-NH-CH₂CH₂-or- (SiR)⁰⁰R⁰⁰⁰-O)_p1In the formula, p1 is an integer of 1 to 12, q1 is an integer of 1 to 3, R⁰⁰And R⁰⁰⁰Have the meaning indicated above.

A particularly preferred radical-X '-Sp' -is- (CH)₂)_p1-、-O-(CH₂)_p1-、-OCO-(CH₂)_p1-、-OCOO-(CH₂)_p1-。

Particularly preferred radicals Sp' are, for example, in each case straight-chain ethylene, propylene, butylene, pentylene, hexylene, heptylene, octylene, nonylene, decylene, undecylene, dodecylene, octadecylene, ethyleneoxyethylene, methyleneoxybutylene, ethylenethioethylene, ethylene-N-methyliminoethylene, 1-methylalkylene, vinylene, propenylene and butenylene.

In the formula (1), ring N¹And ring N²Independently a cycloalkylene group of carbon number 3 to 5, in which at least one-CH group₂-may be substituted by-O-at least one-CH₂CH₂-may be substituted by-CH ═ CH-.

Preferred ring N¹Or ring N²Examples of (b) are divalent groups represented by the following formulae (25-1) to (25-27). A further preferred example is the formulaA divalent group represented by the formula (25-1) to the formula (25-17). Particularly preferred examples are divalent groups represented by the formulae (25-1) to (25-3), and the formulae (25-13) to (25-17). The most preferable examples are divalent groups represented by the formulae (25-1) to (25-3).

In the formula (1), ring A¹And ring A²Independently 1, 4-cyclohexylene, 1, 4-cyclohexenylene, 1, 4-phenylene, naphthalene-2, 6-diyl, 1,2,3, 4-tetrahydronaphthalene-2, 6-diyl, tetrahydropyran-2, 5-diyl, dihydropyran-2, 5-diyl, 1, 3-dioxane-2, 5-diyl, pyridine-2, 5-diyl, or pyrimidine-2, 5-diyl, wherein at least one of these divalent radicals may be fluorine, chlorine, -C.ident.N, -CH₃、-CF₃、-CHF₂、-CH₂F、-OCF₃、-OCHF₂or-OCH₂And F is substituted.

"in these divalent groups, at least one hydrogen may be replaced by fluorine, chlorine, -C.ident.N, -CH₃、-CF₃、-CHF₂、-CH₂F、-OCF₃、-OCHF₂or-OCH₂Preferred examples of the "substitution by F" are divalent groups represented by the following formulae (26-1) to (26-71). Further preferred examples are divalent groups represented by the formulae (26-1) to (26-4), the formulae (26-6), the formulae (26-10) to (26-15), and the formulae (26-54) to (26-59).

Further preferred is ring A¹Or ring A²Is 1, 4-cyclohexylideneA group, a 1, 4-cyclohexenylene group, a 1, 4-phenylene group, a 2-fluoro-1, 4-phenylene group, a 2, 3-difluoro-1, 4-phenylene group, a 2, 6-difluoro-1, 4-phenylene group, a naphthalene-2, 6-diyl group, a tetrahydropyran-2, 5-diyl group, a dihydropyran-2, 5-diyl group, a 1, 3-dioxane-2, 5-diyl group, a pyridine-2, 5-diyl group, a 3-fluoropyridine-2, 5-diyl group, or a pyrimidine-2, 5-diyl group. With respect to the stereoconfiguration of 1, 4-cyclohexylene and 1, 3-dioxan-2, 5-diyl, the trans form is preferred over the cis form.

Especially preferred ring A¹Or ring A²Is 1, 4-cyclohexylene, 1, 4-cyclohexenylene, 1, 4-phenylene, 2-fluoro-1, 4-phenylene, 2, 3-difluoro-1, 4-phenylene, 2, 6-difluoro-1, 4-phenylene, naphthalene-2, 6-diyl, tetrahydropyran-2, 5-diyl, 1, 3-dioxan-2, 5-diyl, pyridine-2, 5-diyl or pyrimidine-2, 5-diyl. Most preferred ring A¹Or ring A²Are 1, 4-cyclohexylene and 1, 4-phenylene, 2-fluoro-1, 4-phenylene, 2, 6-difluoro-1, 4-phenylene, tetrahydropyran-2, 5-diyl or 1, 3-dioxan-2, 5-diyl.

When ring A¹Or ring A²In the case of 1, 4-cyclohexylene group, the clearing point is high and the viscosity is low. When ring A¹Or ring A²In the case of 1, 4-phenylene or in the case of 1, 4-phenylene in which at least one hydrogen is substituted by fluorine, the optical anisotropy is large and the orientation order parameter (orientational order parameter) is relatively large. When ring A¹Or ring A²When the fluorine-substituted 1, 4-phenylene group has at least one hydrogen, the dielectric anisotropy is large.

In the formula (1), Z¹、Z²、Z³And Z⁴Independently a single bond or an alkylene group having 1 to 6 carbon atoms, in which at least one-CH group₂-may be substituted by-O-, -S-, or-CO-, at least one-CH₂CH₂-may be substituted by-CH ═ CH-or-C ≡ C-, at least one of these divalent radicals being substituted by fluorine or chlorine.

Z¹、Z²、Z³Or Z⁴Specific examples thereof are a single bond, -O-, -CH₂-、-CO-、-COO-、-OCO-、-CH₂O-、-OCH₂-、-CF₂O-、-OCF₂-、-CH₂CH₂-、-CH＝CH-、-CF＝CH-、-CH＝CF-、-CF＝CF-、-C≡C-、-CH₂CO-、-COCH₂-、-(CH₂)₄-、-(CH₂)₂COO-、-(CH₂)₂OCO-、-OCO(CH₂)₂-、-COO(CH₂)₂-、-(CH₂)₂CF₂O-、-(CH₂)₂OCF₂-、-OCF₂(CH₂)₂-、-CF₂O(CH₂)₂-、-(CH₂)₃O-、-O(CH₂)₃-、-CH＝CH-(CH₂)₂-、-(CH₂)₂-CH＝CH-、-CH＝CH-CH₂O-, or-OCH₂-CH ═ CH-. With radicals such as-CH-, -CF-, -CH₂O-、-OCH₂The double bond of the-CH-CH-like bonding group has a configuration in which trans is preferable to cis.

Preferred Z¹、Z²、Z³Or Z⁴Is a single bond, -O-, -CH₂-、-CO-、-COO-、-OCO-、-CH₂O-、-OCH₂-、-CF₂O-、-OCF₂-、-CH₂CH₂-、-CH＝CH-、-(CH₂)₄-、-(CH₂)₃O-、-O(CH₂)₃-、-CH＝CH-(CH₂)₂-、-(CH₂)₂-CH＝CH-、-CH＝CH-CH₂O-, or-OCH₂-CH ═ CH-. Further preferred is Z¹、Z²、Z³Or Z⁴Is a single bond, -O-, -CH₂-、-CO-、-COO-、-OCO-、-CH₂O-、-OCH₂-、-CF₂O-、-OCF₂-、-CH₂CH₂-、-CH＝CH-、-(CH₂)₄-、-(CH₂)₃O-、-O(CH₂)₃-、-CH＝CH-(CH₂)₂-, and- (CH)₂)₂-CH ═ CH-. Most preferred Z¹、Z²、Z³Or Z⁴Is a single bond, -O-, -CH₂-、-CO-、-COO-、-OCO-、-CF₂O-、-OCF₂-、-CH₂CH₂-, or-CH ═ CH-.

When Z is¹、Z²、Z³Or Z⁴The single bond has high chemical stability and low viscosity. When Z is¹、Z²、Z³Or Z⁴is-COO-, -OCO-, -CF₂O-or-OCF₂When it is used, the viscosity is low, the dielectric anisotropy is large, and the upper limit temperature is high.

In the formula (1), a is 0, 1,2 or 3, b is 0, 1,2 or 3, and c is 0 or 1. Preferred a is 0, 1, 2. Preferred b is 0, 1, 2. Preferably c is 0. The sum of a and b is preferably 1,2 or 3.

These rings include condensed rings or crosslinked six-membered rings in addition to the usual six-membered rings. When the compound (1) has one ring or two rings, the compatibility with other liquid crystalline compounds is good and the viscosity is low. When the compound (1) has a tricyclic or tetracyclic ring, the upper limit temperature is high. When the compound (1) has four rings or five rings, the temperature range of the liquid crystal phase is wide.

More preferable examples of the formula (1) are the formulae (1-2) to (1-8) described in the item 3. Further preferable examples of the formula (1) are the formula (1-2-1), the formula (1-3-1), the formula (1-4-1), the formula (1-5-1), the formula (1-6-1), the formula (1-7-1), the formula (1-8-1) and the formula (1-8-2) described in the above item 5. Most preferable examples of the formula (1) are the formula (1-2-1-1), the formula (1-3-1-1) to the formula (1-3-1-3), the formula (1-4-1-1) to the formula (1-4-1-7), the formula (1-4-1-14) to the formula (1-4-1-16) described in the item 7.

From the viewpoint of high stability to heat or light and low viscosity, the formula (1-2-1-1) is preferable. From the viewpoint of high clearing point and good compatibility, the formulae (1-3-1-1) to (1-3-1-3) are preferred. From the viewpoint of high clearing point and large optical anisotropy, the formulae (1-4-1-1) to (1-4-1-4) are preferred. From the viewpoint of high clearing point, preferred are formulae (1-4-1-5) to (1-4-1-7), formulae (1-4-1-14) to (1-4-1-16).

2. Synthesis of Compound (1)

The synthesis method of the compound (1) will be described. The compound (1) can be synthesized by appropriately combining the methods of organic synthetic chemistry. Methods for introducing desired terminal groups, rings and bonding groups into starting materials are described in "Organic Synthesis (Organic Synthesis)", (John Wiley & Sons, Inc.), "Organic Reactions (Organic Reactions)", (John Wiley & Sons, Inc.), "Organic chemistry (Comprehensive Organic Synthesis)" the Pergamman Press, and "laboratory chemistry lecture" (Wan.).

2-1 formation of the radical Z

With respect to the formation of the bonding group Z¹To the bonding group Z³First, the flow is shown. Next, the reactions described in the flow of the methods (1) to (11) will be described. In the process, MSG¹(or MSG)²) Is a monovalent organic group having at least one ring. Multiple MSGs for use in a process¹(or MSG)²) The monovalent organic groups represented may be the same or different. The compounds (1A) to (1J) correspond to the compound (1).

(1) Formation of single bonds

The compound (1A) is synthesized by reacting an arylboronic acid (31) synthesized by a conventional method with a halide (32) in the presence of a catalyst such as a carbonate and tetrakis (triphenylphosphine) palladium. The compound (1A) can also be synthesized by reacting a halide (33) synthesized by a conventional method with n-butyllithium, then with zinc chloride, and then with a halide (32) in the presence of a catalyst such as dichlorobis (triphenylphosphine) palladium.

(2) -COO-generation

The halide (33) is reacted with n-butyllithium, and then reacted with carbon dioxide to obtain carboxylic acid (34). Compound (1B) is synthesized by dehydrating compound (35) synthesized by a conventional method and carboxylic acid (34) in the presence of 1,3-Dicyclohexylcarbodiimide (DCC) and 4-Dimethylaminopyridine (DMAP).

(3)-CF₂Formation of O-

Compound (1B) is treated with a sulfurizing agent such as Lawesson's reagent to obtain a thioester (36). Compound (1C) is synthesized by fluorinating thioester (36) with pyridine hydrogen fluoride complex and N-bromosuccinimide (NBS). See, M. Black Star (M.Kuroboshi), et al, communication of chemistry (chem.Lett.) (1992, 827). Compound (1C) can also be synthesized by fluorinating thioester (36) with (Diethylamino) sulfur trifluoride (DAST). Reference is made to journal of organic chemistry (j.org.chem.) by w.h. bonnelle (w.h.bunnelle), et al (1990, 55, 768). Such a linker can also be generated by the method described in Peer. Kirsch et al, applied Germany chemistry (Angew. chem. int. Ed.) (2001, 40, 1480).

(4) -CH-generation

The halide (32) is treated with N-butyllithium, and then reacted with a formamide such as N, N-Dimethylformamide (DMF), to obtain an aldehyde (38). Phosphonium salt (37) synthesized by a conventional method is treated with a base such as potassium tert-butoxide to produce a phosphonium ylide. The phosphorus ylide is reacted with an aldehyde (38) to synthesize a compound (1D). Since the cis-isomer is produced according to the reaction conditions, the cis-isomer is isomerized to the trans-isomer by a conventional method as required.

(5)-CH₂CH₂Generation of

Compound (1E) is synthesized by hydrogenating compound (1D) in the presence of a catalyst such as palladium on carbon.

(6)-(CH₂)₄Generation of

Using phosphonium salt (39) in place of phosphonium salt (37), a compound having- (CH) obtained by the method of the method (4)₂)₂-CH ═ CH-compounds. This was subjected to contact hydrogenation to synthesize compound (1F).

(7)-CH₂CH＝CHCH₂Generation of

Compound (1G) was synthesized according to the method of method (4) using phosphonium salt (40) in place of phosphonium salt (37) and aldehyde (41) in place of aldehyde (38). The trans-isomer is produced according to the reaction conditions, and thus the trans-isomer is isomerized to the cis-isomer by a conventional method as required.

(8) Production of-C.ident.C-

2-methyl-3-butyn-2-ol is reacted with a halide (33) in the presence of a catalyst of palladium dichloride and copper halide, and then deprotected under basic conditions to obtain a compound (32). Compound (1H) is synthesized by reacting compound (42) with halide (32) in the presence of a catalyst of palladium dichloride and copper halide.

(9) Formation of-CF ═ CF-

The halide (33) is treated with n-butyllithium and then reacted with tetrafluoroethylene to obtain a compound (43). Compound (1I) is synthesized by treating halide (32) with n-butyllithium and then reacting the treated halide with compound (43).

(10)-OCH₂Generation of

Aldehyde (38) is reduced with a reducing agent such as sodium borohydride to obtain compound (44). Compound (44) is brominated with hydrobromic acid or the like to obtain bromide (45). Compound (1J) is synthesized by reacting compound (46) with bromide (45) in the presence of a base such as potassium carbonate.

(11)-CF₂CF₂Generation of

A diketone (-COCO-) is fluorinated with sulfur fluoride in the presence of a hydrogen fluoride catalyst according to the method described in J.Am.chem.Soc.) (2001, 123, 5414) to obtain a compound having- (CF) in the presence of a hydrogen fluoride catalyst₂)₂-a compound of (a).

2-2. Ring A¹And ring A²Generation of

As the ring such as 1, 4-cyclohexylene, 1, 4-phenylene, 2-fluoro-1, 4-phenylene or 2, 6-difluoro-1, 4-phenylene, the starting materials are commercially available or widely known. As for the production of tetrahydropyran-2, 5-diyl, refer to paragraphs 0084 to 0107 of Japanese patent laid-open publication No. 2013-241397. As for the production of 1, 3-dioxane-2, 5-diyl, refer to paragraphs 0096 to 0119 of Japanese patent laid-open No. 2009-132927. For the production of pyrimidine-2, 5-diyl and pyridine-2, 5-diyl, see paragraphs 0086 to 0094 of International publication No. 2010/047260.

2-3 Process for synthesizing Compound (1)

Examples of the method for synthesizing the compound (1) are as follows. (51) synthesized by a conventional method was reacted with n-BuLi, and then reacted with isopropoxyboronic acid pinacol to obtain (52). (53) is obtained by reacting (52) in the presence of trimethylolethane and sodium hydroxide. Halogenating (54) to obtain (55). Compound (1) is synthesized by Suzuki coupling reaction of (55) and (53). In these compounds, R¹Ring A¹The definition of the equal sign is the same as that of the sign described in item 1.

3. Liquid crystal composition

3-1. component (A)

The liquid crystal composition of the present invention will be explained. The composition contains at least one compound (1) as component A. The composition may also contain two or more compounds (1). The component of the composition may be only compound (1). In order to exhibit excellent physical properties, the composition preferably contains at least one compound (1) in a range of 1 to 99% by weight. In the composition having positive dielectric anisotropy, the preferable content of the compound (1) is in the range of 5 to 60% by weight. In the composition having negative dielectric anisotropy, the content of the compound (1) is preferably 30% by weight or less.

TABLE 1 dielectric anisotropy of component Compounds

Components of the composition	Component (A) Compound	Dielectric anisotropy
			Component A	Compound (1)	The positive direction is large
Component B	Compounds (2) to (4)	Small
			Component C	Compound (5) to Compound (7)	The positive direction is large
Component D	Compound (8)	The positive direction is large
			Component E	Compound (11) to Compound (19)	Large in negative direction

The composition contains a compound (1) as a component A, and preferably further contains a liquid crystalline compound selected from the group consisting of a component B, a component C, a component D, and a component E shown in Table 1. When the composition is prepared, it is preferable to select the component B, the component C, the component D, and the component E in consideration of the positive, negative, and magnitude of the dielectric anisotropy. The composition may also contain a liquid crystalline compound different from the compounds (1) to (8) and the compounds (11) to (19). The composition may also be free of such liquid crystalline compounds.

The component B is a compound having an alkyl group or the like at both terminal groups. Preferred examples of component B include: transformingCompound (2-1) to compound (2-11), compound (3-1) to compound (3-19), and compound (4-1) to compound (4-7). In these compounds, R¹¹And R¹²Independently an alkyl group having 1 to 10 carbon atoms or an alkenyl group having 2 to 10 carbon atoms, at least one-CH group being present in the alkyl group or the alkenyl group₂-may be substituted by-O-, of which groups at least one hydrogen may be substituted by fluorine.

The component B has a small dielectric anisotropy. Ingredient B is nearly neutral. The compound (2) has an effect of lowering viscosity or adjusting optical anisotropy. The compound (3) and the compound (4) have an effect of expanding the temperature range of the nematic phase or adjusting the optical anisotropy by increasing the upper limit temperature.

The viscosity of the composition becomes lower with increasing the content of component B, but the dielectric anisotropy is reduced. Therefore, the more the content, the more preferable, as long as the required value of the threshold voltage of the element is satisfied. In the case of producing a composition for IPS, VA, or other modes, the content of the component B is preferably 30% by weight or more, and more preferably 40% by weight or more, based on the weight of the liquid crystal composition.

The component C is a compound having a halogen or a fluorine-containing group at the right terminal. Preferred examples of component C include: compound (5-1) to compound (5-16), compound (6-1) to compound (6-116), compound (7-1) to compound (7-59). In these compounds, R¹³Is C1-10 alkyl or C2-10 alkenyl, at least one-CH in the alkyl and alkenyl₂-may be substituted by-O-, of which groups at least one hydrogen may be substituted by fluorine. X¹¹Is fluorine, chlorine, -OCF₃、-OCHF₂、-CF₃、-CHF₂、-CH₂F、-OCF₂CHF₂or-OCF₂CHFCF₃。

Since the component C has positive dielectric anisotropy and very good stability to heat or light, it is used for the production of a composition for IPS, FFS, OCB or other modes. The content of the component C is suitably in the range of 1 to 99% by weight, preferably in the range of 10 to 97% by weight, and more preferably in the range of 40 to 95% by weight, based on the weight of the liquid crystal composition. When the component C is added to a composition having negative dielectric anisotropy, the content of the component C is preferably 30% by weight or less. By adding the component C, the elastic constant of the composition can be adjusted, and the voltage-transmittance curve of the element can be adjusted.

Component D is a compound (8) having the right terminal group-C.ident.N or-C.ident.C-C.ident.N. Preferable examples of the component D include compounds (8-1) to (8-64). In these compounds, R¹⁴Is alkyl with 1 to 10 carbon atoms or alkenyl with 2 to 10 carbon atoms, and at least one of the alkyl and the alkenylIs one of₂-may be substituted by-O-, of which groups at least one hydrogen may be substituted by fluorine. X¹²is-C.ident.N or-C.ident.C-C.ident.N.

Since the component D has positive dielectric anisotropy and a large value, it is used in the case of producing a composition for TN or the like. By adding the component D, the dielectric anisotropy of the composition can be improved. The component D has the effect of expanding the temperature range of the liquid crystal phase, adjusting the viscosity, or adjusting the optical anisotropy. The component D is also useful for adjusting the voltage-transmittance curve of the element.

In the case of preparing a composition for TN or the like mode, the content of the component D is suitably in the range of 1 to 99% by weight, preferably in the range of 10 to 97% by weight, and more preferably in the range of 40 to 95% by weight, based on the weight of the liquid crystal composition. When the component D is added to a composition having negative dielectric anisotropy, the content of the component D is preferably 30% by weight or less. By adding the component D, the elastic constant of the composition can be adjusted, and the voltage-transmittance curve of the element can be adjusted.

The component E is a compound (11) to a compound (19). These compounds have phenylene radicals which are substituted laterally (lateral position) with two halogens, as 2, 3-difluoro-1, 4-phenylene. Preferable examples of the component E include compounds (11-1) to (11-9), compounds (12-1) to (12-19), compounds (13-1) and (13-2), compounds (14-1) to (14-3), compounds (15-1) to (15-3), compounds (16-1) to (16-11), compounds (17-1) to (17-3), compounds (18-1) to (18-3), and compounds (19-1). In these compounds, R¹⁵、R¹⁶And R¹⁷Independently an alkyl group having 1 to 10 carbon atomsOr an alkenyl group having 2 to 10 carbon atoms, at least one-CH being selected from the group consisting of the alkyl group and the alkenyl group₂-may be substituted by-O-, of which groups at least one hydrogen may be substituted by fluorine, and R¹⁷And may be hydrogen or fluorine.

The dielectric anisotropy of the component E is negative and large. Component E is used in the case of preparing compositions for IPS, VA, PSA and the like modes. As the content of the component E increases, the dielectric anisotropy of the composition becomes negative and large, but the viscosity becomes high. Therefore, as long as the required value of the threshold voltage of the element is satisfied, the smaller the content, the more preferable. When the dielectric anisotropy is about-5, the content is preferably 40% by weight or more for sufficient voltage driving.

In the component E, the compound (11) is a bicyclic compound, and therefore has the effect of lowering the viscosity, adjusting the optical anisotropy, or improving the dielectric anisotropy. Since compound (12) and compound (13) are tricyclic compounds and compound (14) is tetracyclic compounds, they have the effect of increasing the upper limit temperature, increasing the optical anisotropy, or increasing the dielectric anisotropy. The compounds (15) to (19) have an effect of improving the dielectric anisotropy.

In the case of producing a composition for IPS, VA, PSA, or other modes, the content of the component E is preferably 40% by weight or more, and more preferably in the range of 50% by weight to 95% by weight, based on the weight of the liquid crystal composition. When the component E is added to a composition having positive dielectric anisotropy, the content of the component E is preferably 30% by weight or less. By adding the component E, the elastic constant of the composition can be adjusted, and the voltage-transmittance curve of the element can be adjusted.

By appropriately combining the component B, the component C, the component D, and the component E with the compound (1), a liquid crystal composition can be prepared which sufficiently satisfies at least one of high stability to heat or light, high upper limit temperature, low lower limit temperature, low viscosity, appropriate optical anisotropy (i.e., large optical anisotropy or small optical anisotropy), large dielectric anisotropy, large specific resistance, appropriate elastic constant (i.e., large elastic constant or small elastic constant), and the like. The usable components of the components comprising the composition have a wide temperature range, short response time, large voltage holding ratio, low threshold voltage, large contrast, small flicker rate and long service life.

When the element is used for a long time, flicker (flicker) may occur in a display screen. The flicker rate (%) may be represented by (| luminance when a positive voltage is applied-luminance when a negative voltage is applied |)/average luminance) × 100. Even if the element is used for a long time, the element having a flicker rate in the range of 0% to 1% is less likely to generate flicker (flicker) on the display screen. The flicker is estimated to be associated with an afterimage of an image, and is generated by generating a difference between the potential of a positive frame and the potential of a negative frame when driven with alternating current. Compositions containing compound (1) are also useful for reducing the generation of flicker.

3-2. additives

The liquid crystal composition is prepared by a conventional method. For example, the component compounds are mixed and dissolved in each other by heating. Additives may be added to the composition according to the use. Examples of the additives are polymerizable compounds, polymerization initiators, polymerization inhibitors, optically active compounds, antioxidants, ultraviolet absorbers, light stabilizers, heat stabilizers, pigments, antifoaming agents, and the like. Such additives are well known to those skilled in the art and are described in the literature.

In a liquid crystal display element having a Polymer Stabilized Alignment (PSA) mode, the composition contains a polymer. The polymerizable compound is added for the purpose of producing a polymer in the composition. The polymerizable compound is polymerized by irradiating ultraviolet rays with a voltage applied between the electrodes, thereby generating a polymer in the composition. By using the method, a proper pretilt angle is achieved, so that an element with shortened response time and improved image retention can be manufactured.

Preferable examples of the polymerizable compound are acrylate, methacrylate, vinyl compound, vinyloxy compound, propylene ether, epoxy compound (oxetane ) and vinyl ketone. Further preferable examples are a compound having at least one acryloyloxy group and a compound having at least one methacryloyloxy group. Further preferred examples include compounds having both an acryloyloxy group and a methacryloyloxy group.

Further preferred examples are the compounds (M-1) to (M-18). In these compounds, R²⁵To R³¹Independently hydrogen or methyl; r³²、R³³And R³⁴Independently hydrogen or C1-5 alkyl, R³²、R³³And R³⁴At least one of (a) is an alkyl group having a carbon number of 1 to 5; v, w, and x are independently 0 or 1; u and y are independently integers from 1 to 10. L is²¹To L²⁶Independently hydrogen or fluorine; l is²⁷And L²⁸Independently hydrogen, fluorine, or methyl.

The polymerizable compound can be rapidly polymerized by adding a polymerization initiator. By optimizing the reaction conditions, the amount of the residual polymerizable compound can be reduced. Examples of photoradical polymerization initiators are TPO 1173 and 4265 from the Darocur (Darocur) series of Basf corporation, 184, 369, 500, 651, 784, 819, 907, 1300, 1700, 1800, 1850 and 2959 from the Irgacure (Irgacure) series.

Additional examples of photo-radical polymerization initiators are 4-methoxyphenyl-2, 4-bis (trichloromethyl) triazine, 2- (4-butoxystyryl) -5-trichloromethyl-1, 3, 4-oxadiazole, 9-phenylacridine, 9, 10-benzophenazine, benzophenone/MILL's ketone mixture, hexaarylbiimidazole/mercaptobenzimidazole mixture, 1- (4-isopropylphenyl) -2-hydroxy-2-methylpropan-1-one, benzildimethylketal, 2-methyl-1- [4- (methylthio) phenyl ] -2-morpholinopropan-1-one, 2, 4-diethylxanthone/p-dimethylaminobenzoic acid methyl ester mixture, and mixtures thereof, Benzophenone/methyl triethanolamine mixtures.

Polymerization can be performed by adding a photo radical polymerization initiator to the liquid crystal composition and then irradiating ultraviolet rays in a state where an electric field is applied. However, there is a high possibility that an unreacted polymerization initiator or a decomposition product of the polymerization initiator causes display defects such as image sticking in the device. To prevent this, photopolymerization may be performed without adding a polymerization initiator. The preferred wavelength of the light to be irradiated is in the range of 150nm to 500 nm. Further, the preferred wavelength is in the range of 250nm to 450nm, and the most preferred wavelength is in the range of 300nm to 400 nm.

When the polymerizable compound is stored, a polymerization inhibitor may be added to prevent polymerization. The polymerizable compound is usually added to the composition in a state where the polymerization inhibitor is not removed. Examples of the polymerization inhibitor are hydroquinone, hydroquinone derivatives such as methyl hydroquinone, 4-t-butyl catechol, 4-methoxyphenol, phenothiazine and the like.

The optically active compound has an effect of preventing reverse twist by imparting a desired twist angle (torsion angle) to the liquid crystal molecules by inducing a helical structure. The helix pitch can be adjusted by adding an optically active compound. Two or more optically active compounds may be added for the purpose of adjusting the temperature dependence of the helical pitch. Preferable examples of the optically active compound include the following compounds (Op-1) to (Op-18). In the compound (Op-18), the ring J is 1, 4-cyclohexylene or 1, 4-phenylene, R²⁸Is an alkyl group having 1 to 10 carbon atoms. The + label indicates asymmetric carbon.

The antioxidant is effective in maintaining a large voltage holding ratio. Preferred examples of the antioxidant include: the following compound (AO-1) and compound (AO-2); irganox 415, Irganox 565, Irganox 1010, Irganox 1035, Irganox 3114, and Irganox 1098 (trade name; BASF corporation). The ultraviolet absorber is effective in preventing a decrease in the upper limit temperature. Preferable examples of the ultraviolet absorber include benzophenone derivatives, benzoate derivatives, triazole derivatives and the like, and specific examples thereof include: the following compound (AO-3) and compound (AO-4); bin (Tinuvin)329, Bin (Tinuvin) P, Bin (Tinuvin)326, Bin (Tinuvin)234, Bin (Tinuvin)213, Bin (Tinuvin)400, Bin (Tinuvin)328, and Bin (Tinuvin)99-2 (trade name; BASF corporation); and 1,4-Diazabicyclo [2.2.2] octane (1,4-Diazabicyclo [2.2.2] octane, DABCO).

Light stabilizers such as hindered amines are preferred because they maintain a large voltage holding ratio. Preferred examples of the light stabilizer include: the following compound (AO-5), compound (AO-6), compound (AO-7), compound (AO-8), and compound (AO-9); dennubin (Tinuvin)144, Dennubin (Tinuvin)765, Dennubin (Tinuvin)770DF, Dennubin (Tinuvin)780 (trade name; BASF corporation); LA-52, LA-57, LA-77Y and LA-77G (trade name; Adeka). The heat stabilizer is effective for maintaining a large voltage holding ratio, and preferable examples thereof include: irgafos 168 (trade name; BASF corporation). In order to be suitable for a guest host (guest host) mode element, a dichroic dye (dichromatic dye) such as an azo dye or an anthraquinone dye is added to the composition. The antifoaming agent is effective in preventing foaming. Preferable examples of the defoaming agent are dimethyl silicone oil, methylphenyl silicone oil and the like.

In the compound (AO-1), R⁴⁰Is alkyl with 1 to 20 carbon atoms, alkoxy with 1 to 20 carbon atoms, -COOR⁴¹or-CH₂CH₂COOR⁴¹Here, R⁴¹Is an alkyl group having 1 to 20 carbon atoms. In the compound (AO-2) and the compound (AO-5), R⁴²Is an alkyl group having 1 to 20 carbon atoms. In the compound (AO-5), R⁴³Is hydrogen, methyl or O (oxygen radical); ring G¹Is 1, 4-cyclohexylene or 1, 4-phenylene; in the compound (AO-7) and the compound (AO-8), ring G²Is 1, 4-cyclohexylene, 1, 4-phenylene, or 1, 4-phenylene in which at least one hydrogen is substituted by fluorine; in the compound (AO-5), the compound (AO-7) and the compound (AO-8), z is 1,2 or 3.

4. Liquid crystal display element

The liquid crystal composition can be used for liquid crystal display elements having operation modes such as PC, TN, STN, OCB, and PSA and driven by an active matrix system. The composition can also be used for liquid crystal display elements having operation modes such as PC, TN, STN, OCB, VA, IPS and the like and driven by a passive matrix method. These elements can be applied to any of reflection type, transmission type, and semi-transmission type.

The compositions are also suitable for Nematic Curvilinear Aligned Phase (NCAP) elements, where the compositions are microencapsulated. The composition can also be used for Polymer Dispersed Liquid Crystal Display (PDLCD) or Polymer Network Liquid Crystal Display (PNLCD). These compositions contain a large amount of a polymerizable compound. On the other hand, when the ratio of the polymerizable compound is 10 wt% or less based on the weight of the liquid crystal composition, a PSA mode liquid crystal display element is produced. The preferred ratio is in the range of 0.1 to 2% by weight. Further, the preferable ratio is in the range of 0.2 to 1.0% by weight. The PSA mode element can be driven by a driving method such as an active matrix method or a passive matrix method. Such an element can be applied to any of a reflection type, a transmission type, and a semi-transmission type.

[ examples ]

1. Examples of Compound (1)

The present invention will be further described in detail by way of examples. The examples are typical examples, and thus the present invention is not limited by the examples. The compound (1) was synthesized by the following procedure. The synthesized compound is identified by Nuclear Magnetic Resonance (NMR) analysis or the like. The physical properties of the compound or the composition and the characteristics of the device were measured by the following methods.

NMR analysis: JNM-ECZS (500MHz) manufactured by Japan Electron Ltd was used for the measurement.¹In the measurement of H-NMR, a sample was dissolved in CDCl₃The measurement was performed at room temperature under the conditions of 500MHz and 16 cumulative times in the deuterated solvent. Tetramethylsilane was used as an internal standard.¹⁹In the measurement of F-NMR, CFCl was used₃As an internal standard, the number of times is accumulated to 24 times. In the description of the nmr spectra, s is a singlet (singlet), d is a doublet (doublt), t is a triplet (triplet), q is a quartet (quatet), quin is a quintet (quintet), sext is a sextet (sextet), m is a multiplet (multiplex), and br is a broad (broad).

Gas chromatographic analysis: for measurement, a gas chromatograph model GC-2010 manufactured by Shimadzu corporation was used. The column used was a capillary column DB-1 (length 60m, inner diameter 0.25mm, film thickness 0.25 μm) manufactured by Agilent Technologies Inc. As the carrier gas, helium (1mL/min) was used. The temperature of the sample vaporization chamber was set to 300 ℃, and the temperature of a Detector (Flame Ionization Detector, FID)) was set to 300 ℃. The sample was dissolved in acetone to prepare a 1 wt% solution, and 1. mu.l of the obtained solution was injected into the sample vaporization chamber. The recorder uses a GCsolution system manufactured by Shimadzu corporation, and the like.

Quality analysis of a gas chromatograph: for measurement, a QP-2010Ultra gas chromatograph mass spectrometer manufactured by Shimadzu corporation was used. The column used was a capillary column DB-1 (length 60m, inner diameter 0.25mm, film thickness 0.25 μm) manufactured by Agilent Technologies Inc. As carrier gas, helium (1ml/min) was used. The temperature of the sample vaporization chamber was set to 300 ℃, the temperature of the ion source was set to 200 ℃, the ionization voltage was set to 70eV, and the emission current was set to 150 uA. The sample was dissolved in acetone to prepare a 1 wt% solution, and 1. mu.l of the obtained solution was injected into the sample vaporization chamber. The recorder uses the GCMSsolution system manufactured by shimadzu corporation.

High Performance Liquid Chromatography (HPLC) analysis: for the measurement, prominine (LC-20 AD; SPD-20A) manufactured by Shimadzu corporation was used. As the column, YMC-Pack ODS-A (length: 150mm, inner diameter: 4.6mm, particle diameter: 5 μm) manufactured by YMC was used. The dissolution liquid is properly mixed with acetonitrile and water. As the detector, an UltraViolet (UV) detector, a Refractive Index (RI) detector, a CORONA (CORONA) detector, or the like is suitably used. In the case of using a UV detector, the detection wavelength was set to 254 nm. A sample was dissolved in acetonitrile to prepare a 0.1 wt% solution, and 1 μ L of the solution was introduced into the sample chamber. The recorder used C-R7Aplus manufactured by Shimadzu corporation.

Ultraviolet and visible light spectroscopy: PharmaSpec UV-1700, manufactured by Shimadzu corporation, was used for the measurement. The detection wavelength was set to 190nm to 700 nm. A sample was dissolved in acetonitrile to prepare a solution of 0.01mmol/L, and the solution was placed in a quartz cell (optical path length 1cm) and measured.

Measurement of the sample: when the phase structure and transition temperature (clearing point, melting point, polymerization initiation temperature, etc.) are measured, the compound itself is used as a sample. When physical properties such as the upper limit temperature, viscosity, optical anisotropy, and dielectric anisotropy of a nematic phase are measured, a mixture of a compound and a mother liquid crystal is used as a sample.

When a sample in which a compound and a mother liquid crystal are mixed is used, an extrapolated value is calculated by the following equation, and the extrapolated value is described.

< extrapolated value > - (100 × < measured value of sample > - < weight% of mother liquid crystal > × < measured value of mother liquid crystal)/< weight% of compound >.

Mother liquid crystal (a): when the dielectric anisotropy of the compound is zero or positive, the following mother liquid crystal (A) is used. The proportions of the respective components are expressed in% by weight.

The ratio of the compound to the mother liquid crystal (a) was set to 15% by weight: 85% by weight. When crystals (or smectic phases) are precipitated at 25 ℃ in this ratio, the ratio of the compound to the mother liquid crystal (a) is changed to 10% by weight in this order: 90 wt%, 5 wt%: 95% by weight, 1% by weight: 99 wt% of the sample was measured at a rate at which no crystal (or smectic phase) precipitated at 25 ℃. Unless otherwise specified, the ratio of the compound to the mother liquid crystal (a) is 15% by weight: 85% by weight.

Mother liquid crystal (B): the mother liquid crystal (B) containing the following fluorine-based compound as a component is also used. The proportion of the components of the mother liquid crystal (B) is expressed in% by weight.

The ratio of the compound to the mother liquid crystal (B) was set to 20 wt%: 80% by weight. When crystals (or smectic phases) are precipitated at 25 ℃ in this ratio, the ratio of the compound to the mother liquid crystal (B) is changed to 15% by weight in this order: 85 wt%, 10 wt%: 90 wt%, 5 wt%: 95% by weight, 1% by weight: 99% by weight, at a rate at which no crystal (or smectic phase) precipitates at 25 ℃. Unless otherwise specified, the ratio of the compound to the mother liquid crystal (B) is 20% by weight: 80% by weight.

The determination method comprises the following steps: the physical properties were measured by the following methods. These methods are described in the JEITA standard (JEITA. ED-2521B) which is proposed by the society of electronic Information Technology Industries (Japan Electronics and Information Technology Industries Association). Methods of modifying the compounds are also used. The TN cell used for the measurement was not mounted with a Thin Film Transistor (TFT).

(1) Phase structure: the sample was placed on a hot plate (hot stage) of a melting point measuring apparatus equipped with a polarizing microscope, model FP-52 produced by Mettler corporation. The phase state and its change were observed by a polarization microscope while heating the sample at a rate of 3 ℃/min to determine the phase type.

(2) Transition temperature (. degree. C.): for the measurement, a scanning calorimeter Diamond DSC system manufactured by Perkin Elmer (Perkin Elmer) or a high sensitivity differential scanning calorimeter X-DSC7000 manufactured by SII Nanotechnology (SII Nanotechnology) was used. The temperature of the sample was raised and lowered at a rate of 3 ℃/min, and the starting point of the endothermic peak or exothermic peak associated with the phase change of the sample was determined by extrapolation, thereby determining the transition temperature. The melting point of the compound and the polymerization initiation temperature were also measured using the apparatus. The temperature at which the compound changes from a solid to a liquid crystal phase such as a smectic phase or a nematic phase may be simply referred to as "lower limit temperature of liquid crystal phase". The temperature at which the compound changes from a liquid crystal phase to a liquid is sometimes referred to simply as "clearing point".

The crystals are denoted as C. When the two types of crystals can be distinguished from each other, they are represented by C₁Or C₂. The smectic phase is denoted S and the nematic phase is denoted N. When the phases are added to distinguish each other as in the case of the smectic A phase, the smectic B phase, the smectic C phase, and the smectic F phase, they are respectively represented as S_A、S_B、S_CAnd S_F. The liquid (isotropic) is denoted as I. The transition temperature is expressed, for example, as "C50.0N 100.0I". It shows that the transition temperature from the crystal to the nematic phase is 50.0 ℃ and the transition temperature from the nematic phase to the liquid is 100.0 ℃.

(3) Compatibility of the compounds: a mother liquid crystal was mixed with a compound so that the proportion of the compound became 20 wt%, 15 wt%, 10 wt%, 5 wt%, 3 wt%, or 1 wt% to prepare a sample. The sample was placed in a glass vial and kept in a freezer at-20 ℃ or-30 ℃ for a fixed period. The nematic phase of the sample was observed to be maintained, or crystals (or smectic phase) were observed to be precipitated. The condition under which the nematic phase is maintained is used as a criterion for compatibility. The ratio of the compounds and the temperature of the freezer may be changed as needed.

(4) Upper limit temperature (T) of nematic phase_NIOr NI; c): melting point measuring device with polarizing microscopeThe sample was placed on a hot plate and heated at a rate of 1 ℃/min. The temperature at which a part of the sample changes from nematic phase to isotropic liquid is measured. When the sample is a mixture of the compound (1) and a mother liquid crystal, the symbol T is used_NIAnd (4) showing. When the sample is a mixture of the compound (1) and a compound selected from the compounds (2) to (15), it is represented by symbol NI. The upper limit temperature of the nematic phase may be simply referred to as "upper limit temperature".

(5) Lower limit temperature (T) of nematic phase_C(ii) a C): the nematic phase was observed after placing the sample in a glass bottle and keeping the bottle in a freezer at 0 ℃, -10 ℃, -20 ℃, -30 ℃ and-40 ℃ for 10 days. For example, when a sample maintains a nematic phase at-20 ℃ and changes to a crystalline or smectic phase at-30 ℃, it is described as T_C< -20 ℃. The lower limit temperature of the nematic phase may be simply referred to as "lower limit temperature".

(6) Viscosity (bulk viscosity;. eta.;. measured at 20 ℃ C.;. mPas): for the measurement, an E-type rotational viscometer manufactured by tokyo counter gmbh was used.

(7) Viscosity (rotational viscosity; γ 1; measured at 25 ℃; mPas): the measurement was carried out according to the method described in Molecular Crystals and Liquid Crystals (vol.259, 37(1995)) of M.J.et al (M.Imai). A sample was placed in a TN cell having a twist angle of 0 ℃ and a gap (cell gap) of 5 μm between two glass substrates. The element was applied with a voltage in 0.5V in a stepwise manner within 16V to 19.5V. After 0.2 seconds had not been applied, the application was repeated with only one square wave (square pulse; 0.2 seconds) and without (2 seconds). The peak current (peak current) and peak time (peak time) of the transient current (transient current) resulting from the application are measured. Values for rotational viscosity are obtained from these measurements and equation (8) on page 40 of the paper by M.J.et al. The value of the dielectric anisotropy necessary for the calculation was determined by the following method using an element for measuring the rotational viscosity.

(8) Optical anisotropy (refractive index anisotropy; measured at 25 ℃; Δ n): the measurement was performed using a light having a wavelength of 589nm by an Abbe refractometer having a polarizing plate attached to an eyepiece. After rubbing the surface of the main prism in one direction, the sample was dropped onto the main prism. The refractive index (n/is measured when the direction of polarization is parallel to the direction of rubbing. The refractive index (n ″) is measured when the direction of the polarized light is perpendicular to the direction of the rubbing. The value of the optical anisotropy (Δ n) is calculated from the equation of Δ n ═ n/n ″.

(9) Dielectric anisotropy (. DELTA.. di-elect cons.; measured at 25 ℃): a sample was placed in a TN cell having a cell gap of 9 μm and a twist angle of 80 degrees between two glass substrates. A sine wave (10V, 1kHz) was applied to the element, and the dielectric constant (. epsilon. /) in the long axis direction of the liquid crystal molecules was measured after 2 seconds. Sine wave (0.5V, 1kHz) was applied to the element, and the dielectric constant (∈ ∈ in the short-axis direction of the liquid crystal molecules was measured after 2 seconds. The value of the dielectric anisotropy is calculated from the equation of Δ ∈/∈ ″.

(10) Elastic constant (K; measured at 25 ℃ C.; pN): for the measurement, an LCR model HP4284A manufactured by Yokogawa Hewlett-Packard GmbH was used. A sample was placed in a horizontally oriented cell having a gap (cell gap) of 20 μm between two glass substrates. An electric charge of 0V to 20V was applied to the element, and the electrostatic capacitance (C) and the applied voltage (V) were measured. These measurement values were fitted (fitting) using equation (2.98) and equation (2.101) described in "liquid crystal device manual (journal industry news agency)" page 75, and equation (2.99), and K was obtained from equation (2.99)₁₁And K₃₃The value of (c). Next, in equation (3.18) described on page 171, K obtained as described above is used₁₁And K₃₃To calculate K₂₂. The elastic constant K is determined from K₁₁、K₂₂And K₃₃Is expressed as an average value of (a).

(11) Threshold voltage (Vth; measured at 25 ℃; V): for the measurement, a Liquid Crystal Display (LCD) 5100 type luminance meter manufactured by Otsuka electronics Ltd was used. The light source is a halogen lamp. A sample was placed in a TN element of normal white mode (normal white mode) in which the distance between two glass substrates (cell gap) was 0.45/. DELTA.n (μm) and the twist angle was 80 degrees. The voltage (32Hz, rectangular wave) applied to the element was increased stepwise from 0V to 10V in units of 0.02V. At this time, the element was irradiated with light from the vertical direction, and the amount of light transmitted through the element was measured. A voltage-transmittance curve was prepared in which the transmittance was 100% when the light amount reached the maximum and the transmittance was 0% when the light amount was the minimum. The threshold voltage is represented by a voltage at which the transmittance reaches 90%.

(12) Voltage holding ratio (VHR-1; measured at 25;%): the TN element used for the measurement had a polyimide alignment film, and the interval (cell gap) between the two glass substrates was 5 μm. The elements are sealed with an adhesive that is cured with ultraviolet light after the sample is added. The element was charged by applying a pulse voltage (5V, 60 μ s) at 25 ℃. The decayed voltage was measured by a high-speed voltmeter for a period of 16.7 milliseconds, and the area a between the voltage curve per unit cycle and the horizontal axis was determined. The area B is the area when not attenuated. The voltage holding ratio is expressed as a percentage of the area a to the area B.

(13) Voltage holding ratio (VHR-2; measured at 80;%): the voltage holding ratio was determined by the method described, except that the measurement was performed at 80 ℃ instead of 25 ℃. The result obtained is shown by the symbol VHR-2.

(14) Resistivity (. rho.; measured at 25 ℃ C.;. OMEGA. cm): 1.0mL of the sample was injected into a container equipped with an electrode. A DC voltage (10V) was applied to the vessel, and a DC current after 10 seconds was measured. The resistivity was calculated according to the following equation.

(resistivity) { (voltage) × (capacitance of container) }/{ (direct current) × (dielectric constant of vacuum) }

(15) Response time (. tau.; measured at 25 ℃ C.; ms): for the measurement, an LCD5100 type luminance meter manufactured by Otsuka electronics Co., Ltd was used. The light source is a halogen lamp. The Low pass filter (Low-pass filter) was set to 5 kHz. A sample was placed in a TN element of normal white mode (normal white mode) in which the gap between two glass substrates (cell gap) was 5.0 μm and the twist angle was 80 degrees. A square wave (60Hz, 5V, 0.5 sec) was applied to the element. At this time, the element was irradiated with light from the vertical direction, and the amount of light transmitted through the element was measured. The transmittance was regarded as 100% when the light amount reached the maximum, and as 0% when the light amount was the minimum. The rise time (τ r: rise time; millisecond) is the time required for the transmittance to change from 90% to 10%. The fall time (τ f: fall time; milliseconds) is the time required for the transmittance to change from 10% to 90%. The response time is represented by the sum of the rise time and the fall time found in the above manner.

(16) Scintillation rate (measured at 25;%): a multimedia display tester (3298F) manufactured by york motor (gang) was used for the measurement. The light source is an LED. The sample was placed in an FFS cell of a normally black mode (normal black mode) in which the gap between two glass substrates (cell gap) was 3.5 μm and the rubbing directions were antiparallel. The element is sealed using an adhesive hardened with ultraviolet rays. A voltage is applied to the element, and the voltage at which the amount of light transmitted through the element is maximized is measured. The sensor section is brought close to the element while the voltage is applied to the element, and the flicker rate displayed is read.

Raw materials: sommix (Solmix) (registered trademark) A-11 is a mixture of ethanol (85.5%), methanol (13.4%) and isopropanol (1.1%) and is available from Nippon spirit, Inc. Tetrahydrofuran is sometimes abbreviated as thf (tetrahydrofuran). Tetrabutylammonium bromide is sometimes abbreviated as tbab (tetrabutyllamonium bromide). N, N-dimethylformamide is sometimes abbreviated as DMF (dimethyl formamide). 2-propanol is sometimes abbreviated IPA (iso Propyl alcohol). 1,2-Dimethoxyethane is sometimes abbreviated as DME (1, 2-Dimethoxyethane). Potassium hexamethyldisilazane is sometimes referred to simply as KHMDS.

[ Synthesis example 1]

Synthesis of Compound (a-6)

First step of

2-ethylthiophene (5.00g, 43.2mmol) and THF (25ml) were placed in a reactor under nitrogen and cooled to-70 ℃. An n-BuLi hexane solution (1.55mol/L, 32.1mL, 49.7mmol) was added dropwise thereto, and the mixture was stirred for 1 hour while maintaining-70 ℃. Subsequently, a solution of isopropoxyboronic acid pinacol (9.74g, 49.7mmol) in THF (10ml) was slowly added dropwise thereto, and then the temperature was raised to room temperature. The reaction mixture was poured into water, and the aqueous layer was extracted with ethyl acetate. The organic layer thus prepared was washed with water and saturated brine in this order, and dried over anhydrous magnesium sulfate. The solution was concentrated under reduced pressure, and the residue was purified by silica gel column chromatography (heptane/ethyl acetate 9/1, volume ratio), thereby obtaining compound (t-1) (7.84g, yield 76.1%).

Second step of

Compound (t-1) (7.84g, 32.9mmol), trimethylolethane (4.04g, 32.9mmol), sodium hydroxide (1.36g, 32.9mmol), water (1.78mL, 98.8mmol) and 1, 4-dioxane (165mL) were placed in a reactor, heated to 60 ℃ and stirred for 6 hours. After cooling to room temperature, 200mL of heptane was added and the mixture was stirred. The precipitate was collected by filtration, washed with heptane and dried to obtain compound (t-2) (9.43g, yield 99.9%).

The third step

1-bromo-4-iodobenzene (27.8g, 98.3mmol) and THF (250mL) were placed in a reactor under nitrogen and cooled to-50 ℃. To this solution was added dropwise a solution of isopropyl magnesium chloride-lithium chloride complex (1.3mol/L, 74.1mL, 98.3mmol), and the mixture was stirred at-40 ℃ for 2 hours. Next, cyclopentanone (6.89g, 81.9mmol) was added dropwise, and the temperature was raised to room temperature after the dropwise addition. The reaction mixture was poured into an aqueous ammonium chloride solution, and the aqueous layer was extracted with ethyl acetate. The organic layer thus prepared was washed with water and dried over anhydrous magnesium sulfate. The solution was concentrated under reduced pressure, and the residue was purified by silica gel column chromatography (toluene), whereby compound (t-3) (15.1g, yield 87.0%) was obtained.

The fourth step

Compound (t-3) (13.1g, 54.4mmol), 3, 5-difluorophenylboronic acid (10.3g, 65.3mmol), tetrakis (triphenylphosphine) palladium (1.94g), potassium carbonate (15.1g, 109mmol), tetrabutylammonium bromide (5.37g, 16.3mmol), toluene (130mL), 2-propanol (130mL) and water (65mL) were placed in a reactor under a nitrogen atmosphere, heated under reflux for 3 hours, and after completion of the reaction, cooled to room temperature. The reaction mixture was poured into water, and the aqueous layer was extracted with toluene. The organic layer thus prepared was washed with sodium hydrogencarbonate water and saturated brine in this order and dried over anhydrous magnesium sulfate. The solution was concentrated under reduced pressure, and the residue was purified by silica gel column chromatography (toluene), thereby obtaining compound (t-4) (7.68g, yield 51.4%).

The fifth step

Under a nitrogen atmosphere, compound (t-4) (7.68g, 28.0mmol) and dichloromethane (40mL) were placed in a reactor and cooled to-70 ℃. A solution of triethylsilane (6.71mL, 42.0mmol) in methylene chloride (40mL) was added dropwise, followed by dropwise addition of boron trifluoride-diethyl ether complex (5.30mL, 42.0mmol), and the temperature was raised to room temperature. The reaction mixture was poured into sodium bicarbonate water, and the aqueous layer was extracted with toluene. The organic layer thus prepared was washed with water and saturated brine, and dried over anhydrous magnesium sulfate. The solution was concentrated under reduced pressure, and the residue was purified by silica gel column chromatography (heptane), whereby compound (t-5) (8.05g, yield 99.9%) was obtained.

The sixth step

Compound (t-5) (8.05g, 31.2mmol) and THF (60ml) were placed in a reactor under nitrogen and cooled to-70 ℃. An n-BuLi hexane solution (1.60mol/L, 29.8mL, 49.7mmol) was added dropwise thereto, and the mixture was stirred for 1 hour while maintaining-70 ℃. Subsequently, a solution of iodine (12.1g, 47.7mmol) in THF (120ml) was slowly added dropwise, and then the temperature was raised to room temperature. The reaction mixture was poured into an aqueous sodium sulfite solution and stirred, and the aqueous layer was extracted with toluene. The organic layer thus prepared was washed with an aqueous sodium sulfite solution and a saturated brine in this order, and dried over anhydrous magnesium sulfate. The solution was concentrated under reduced pressure, and the residue was purified by silica gel column chromatography (heptane) and recrystallization (sommix/heptane 10/1, volume ratio), thereby obtaining compound (t-6) (9.01g, yield 75.2%).

Seventh step

(t-6) (4.88g, 12.7mmol), (t-2) (7.33g, 28.0mmol), palladium acetate (0.0856g, 0.380mmol), (t-7) (0.228g, 0.760mmol) and DMF (75mL) were placed in a reactor under nitrogen and stirred at 50 ℃ for 3 hours. After the reaction, the mixture was cooled to room temperature, poured into water, and the aqueous layer was extracted with toluene, and the organic layer thus prepared was washed with water and saturated brine, and dried over anhydrous magnesium sulfate. The solution was concentrated under reduced pressure, and the residue was purified by silica gel chromatography (heptane). After purification, the mixture was placed in a reactor under hydrogen atmosphere with 5% palladium on carbon (0.123g), toluene (25mL) and 2-propanol (25mL) and stirred for 4 hours. After completion of the reaction, 5% palladium on carbon was separated by filtration, the filtrate was concentrated, and the residue was purified by silica gel column chromatography (heptane) and recrystallization (somite (Solmix)/ethyl acetate 10/3, volume ratio), whereby compound (a-6) (1.99g, yield 42.5%) was obtained.

¹H-NMR(ppm；CDCl₃)：δ7.51(d,J＝8.0Hz,2H)、7.41(d,J＝4.0Hz,1H)、7.33(d,J＝8.0Hz,2H)、7.23-7.19(m,2H)、6.85(d,J＝3.5Hz、1H)、3.08-3.01(m,1H)、2.91(q、J＝7.5Hz、2H)、2.14-2.07(m、2H)、1.88-1.58(m、6H)、1.37(t、J＝7.5Hz、3H).

Transition temperature: C77.5N 105.1I.

Upper limit temperature (T)_NI) 105.0 ℃ under normal temperature; dielectric anisotropy (Δ ∈) ═ 6.9; optical anisotropy (Δ n) of 0.270; viscosity (. eta.) was 39.8 mPas.

Comparative example 1

The following compound (S-1) was selected as a comparative compound. The compound is a compound (PUS-3-2) described in International publication No. 2010/099853, and synthesized according to the method described in the publication.

¹H-NMR(ppm；CDCl₃)：δ7.51-7.49(m,2H)、7.41(d,J＝3.5Hz,1H)、7.26(d,J＝8.0Hz,2H)、7.23-7.19(m,2H)、6.84(td,J＝1.0,3.5Hz、1H)、2.91(q、J＝7.5Hz、2H)、2.63(t、J＝7.5Hz、2H)、1.68(sext、J＝7.5Hz、2H)、1.36(t、J＝7.5Hz、3H)、0.971(t、J＝7.5Hz、3H).

Transition temperature: C44.7N 89.1I.

Upper limit temperature (T)_NI) The temperature is 101 ℃; dielectric anisotropy (Δ ∈) ═ 6.87; optical anisotropy (Δ n) of 0.270; viscosity (. eta.) was 17.4 mPas.

Comparison of physical Properties

Table 2 physical Properties of Compound (a-6) and comparative Compound (S-1)

Physical properties of the compound (a-6) obtained in Synthesis example 1 and the comparative compound (S-1) are summarized in Table 2. As can be seen from Table 2: the compound (a-6) is good in that the upper limit temperature is high.

2. Synthesis of Compound (1)

The compound (1) was synthesized according to "2. Synthesis of the compound (1)" and the synthesis examples described above. Examples of such compounds include the compounds (a-1) to (a-96) and the compounds (b-1) to (b-92) shown below.

[ Industrial Applicability ]

The liquid crystalline compound of the present invention has good physical properties. Liquid crystal compositions containing the compounds are widely used in liquid crystal display devices used in personal computers, televisions, and the like.

Claims

1. A compound represented by the formula (1),

in the formula (1), the reaction mixture is,

R²is hydrogen, fluorine, chlorine, -C ≡ N, -C ≡ C-C ≡ N,-NCS、-SCN、-SF₅P-Sp-or C1-15 alkyl, R²In (1), at least one-CH₂-may be substituted by-O-, -S-, or-CO-, at least one-CH₂CH₂-may be substituted by-CH ═ CH-or-C ≡ C-, at least one hydrogen may be substituted by fluoro or chloro;

p is a polymerizable group;

sp is a spacer group or a single bond;

a is 0, 1,2 or 3, b is 0, 1,2 or 3, and c is 0 or 1.

2. The compound according to claim 1, represented by formula (1a),

in the formula (1a), the compound (A),

p is a polymerizable group;

sp is a spacer group or a single bond;

a is 0, 1,2 or 3, and b is 0, 1,2 or 3.

3. The compound according to claim 1 or 2, represented by any one of formula (1-1) to formula (1-10),

in the formulae (1-1) to (1-10),

R²is fluorine, chlorine, -C.ident.N, -C.ident.C-C.ident.N, -NCS, -SCN, -SF-N₅Or an alkyl group having 1 to 15 carbon atoms, R²In (1), at least one-CH₂-may be substituted by-O-, -S-, or-CO-, at least one-CH₂CH₂-may be substituted by-CH ═ CH-or-C ≡ C-, at least one hydrogen may be substituted by fluoro or chloro;

Z¹、Z²and Z³Independently a single bond or alkylene having 1 to 6 carbon atoms, Z¹、Z²And Z³In (1), at least one-CH₂-may be substituted by-O-, -S-, or-CO-, at least one-CH₂CH₂Can be passed through-CH-or-C ≡ C-substituted, at least one hydrogen may be substituted by fluoro or chloro.

4. The compound according to claim 3, wherein in the formulae (1-1) to (1-10),

ring N¹Is 1, 2-cyclopropylene, 1, 3-cyclobutylene, or 1, 3-cyclopentylene;

5. The compound according to claim 1 or 2, represented by any one of formula (1-1-1), formula (1-2-1), formula (1-3-1), formula (1-4-1), formula (1-5-1), formula (1-6-1), formula (1-7-1), formula (1-8-2), formula (1-9-1), formula (1-9-2), formula (1-10-1), or formula (1-10-2),

ring N¹Is 1, 2-cyclopropylene, 1, 3-cyclobutylene, or 1, 3-cyclopentylene;

6. The compound according to claim 5, wherein in the formula (1-1-1), the formula (1-2-1), the formula (1-3-1), the formula (1-4-1), the formula (1-5-1), the formula (1-6-1), the formula (1-7-1), the formula (1-8-2), the formula (1-9-1), the formula (1-9-2), the formula (1-10-1), or the formula (1-10-2),

ring N¹Is 1, 2-cyclopropylene, 1, 3-cyclobutylene, or 1, 3-cyclopentylene;

7. The compound according to claim 1 or 2, represented by formula (1-2-1-1), formula (1-3-1-1) to formula (1-3-1-6), or formula (1-4-1-1) to formula (1-4-1-18),

ring N¹Is 1, 2-cyclopropylene, 1, 3-cyclobutylene, or 1, 3-cyclopentylene;

8. The compound according to claim 7, wherein in the formula (1-2-1-1), the formula (1-3-1-1) to the formula (1-3-1-6), or the formula (1-4-1-1) to the formula (1-4-1-18),

R²is fluorine, -OCF₃-C ≡ N, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, an alkoxyalkyl group having 2 to 5 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, or an alkenyloxy group having 2 to 5 carbon atoms;

ring N¹Is 1, 2-cyclopropylene, 1, 3-cyclobutylene, or 1, 3-cyclopentylene;

9. A liquid crystal composition comprising at least one compound according to any one of claims 1 to 8.

10. The liquid crystal composition according to claim 9, further comprising at least one compound selected from the group of compounds represented by formulae (2) to (4),

in the formulae (2) to (4),

11. The liquid crystal composition according to claim 9 or 10, further comprising at least one compound selected from the group of compounds represented by formulae (5) to (7),

in the formulae (5) to (7),

Ring C¹Ring C²And ring C³Independently 1, 4-cyclohexylene, 1, 4-phenyleneA group, a 1, 4-phenylene group in which at least one hydrogen is substituted with fluorine, a tetrahydropyran-2, 5-diyl group, a 1, 3-dioxan-2, 5-diyl group, or a pyrimidine-2, 5-diyl group;

L¹¹And L¹²Independently hydrogen or fluorine.

12. The liquid crystal composition according to claim 9 or 10, further comprising at least one compound selected from the group of compounds represented by formula (8),

in the formula (8), the reaction mixture is,

X¹²is-C.ident.N or-C.ident.C-C.ident.N;

L¹³and L¹⁴Independently hydrogen or fluorine;

i is 1,2,3, or 4.

13. The liquid crystal composition according to claim 9 or 10, further comprising at least one compound selected from the group of compounds represented by formula (11) to formula (19),

in the formulae (11) to (19),

L¹⁵And L¹⁶Independently fluorine or chlorine;

S¹¹is hydrogen or methyl;

x is-CHF-or-CF₂-；

14. A liquid crystal display element comprising the liquid crystal composition according to any one of claims 9 to 13.