TWI477587B - A liquid crystal compound having hexahydro-indene-based structure, a liquid crystal composition comprising said compound and application thereof - Google Patents

Description

Liquid crystal compound containing hexahydroquinone structure, liquid crystal group containing the same Compound and liquid crystal display

The present invention relates to a liquid crystal compound and a liquid crystal composition comprising the liquid crystal compound, and more particularly to a novel liquid crystal compound containing a hexahydroindole structure, and a liquid crystal composition comprising the liquid crystal compound.

Physically, the matter is divided into three states, namely solid, liquid and gaseous. In nature, most materials exhibit only three states of solid state, liquid state and gas state with temperature. Liquid crystal is a new material state different from the usual solid, liquid and gaseous states. The liquid crystal can be in a certain temperature range. The state of matter in which both the liquid and the crystal are characteristic, also referred to as the liquid crystal phase or the intermediate phase, is also referred to as the fourth state of matter.

There are many types of liquid crystals, and there are thousands of naturally occurring and synthetic liquid crystals, but they are basically organic compounds. According to the conditions formed by the liquid crystal phase, the liquid crystal can be classified into a thermotropic liquid crystal, a lyotropic liquid crystal, an inductive liquid crystal, and a flow-through liquid crystal.

Currently, liquid crystal materials for display are basically thermotropic liquid crystals. Thermotropic liquid crystals can be classified into smectic liquid crystals (Smectic, also known as smectic liquid crystals), nematic liquid crystals (Nematic, also known as filamentous liquid crystals), and cholesterol phase liquid crystals (Cholesteric). It is called spiral liquid crystal). The physical properties of these phases are known. Molecular structural features of compounds used in the field of optoelectronics, usually having a rigid backbone comprising, for example, 1,4-phenylene or 1,4-cyclohexylene or heterocyclic systems for attachment, as far as possible The distant sites are substituted by so-called terminal groups such as alkyl, alkoxy or cyano groups.

The liquid crystal composition used in the field of optoelectronics is composed of a mixture of these compounds, and a compound which does not have a mutual transformation from a crystal phase to a liquid crystal is also used therein. Classified by liquid crystal display, liquid crystal mixture can be divided into dynamic scattering type (DS type), guest main type (GH type), twisted nematic type (TN type), super twisted nematic type (STN type), thin film transistor type ( TFT type) and ferroelectric type (FLC type). Liquid crystal materials have been widely used in the production of liquid crystal display elements such as tablet computers, various measuring instruments, automotive instrument panels, notebook computers, mobile phones, computers, and televisions.

To date, various liquid crystal materials have been synthesized into a variety of compounds, depending on the mode of display or the manner of driving and their use. On the other hand, the demand for improving the performance of liquid crystal display elements has been increasing year by year. To meet this demand, it is necessary to continue to develop novel liquid crystal compounds.

It is an object of the present invention to provide a novel liquid crystal compound containing a hexahydroindole structure.

Thus, the novel liquid crystal compound containing the hexahydroindole structure of the present invention has the structure of the general formula (I):

Wherein R ₁ represents -H, -F, a straight or branched alkyl or alkoxy group having from 1 to 20 carbon atoms which is substituted or unsubstituted with at least one halogen, wherein at least R ₁ One -CH ₂ - may be independently independently -O-, -S-, -SiH ₂ -, -CH=CH-, -C≡C-, -CF=CF-, -CH=CF-, -COO- Or -OCO-substitution, provided that the heteroatoms are not directly connected to each other, and the O, S and Si atoms are not directly bonded to the ring; R ₂ represents -H, -F, -Cl, -CN, -NCS, -SCN, - OCN, -NCO, a linear or branched alkyl or alkoxy group having 1 to 20 carbon atoms substituted or unsubstituted with at least one halogen, wherein at least one -CH ₂ - in the R ₂ may be independently -O-, -S-, -SiH ₂ -, -CH=CH-, -C≡C-, -CF=CF-, -CH=CF-, , -COO- or -OCO-substitution, provided that the heteroatoms are not directly connected to each other; A ₁ represents , or ; A ₂ , A ₃ and A ₄ are the same or different and each independently represents , , or Ring structure; alternatively, the ring structure represented by A ₁ , A ₂ , A ₃ , and A ₄ conforms to at least one of the following (a), (b), (c), and (d): (a ) a cyclic structure in which one or more hydrogen atoms may be each independently -D, -F, -Cl, -CN, -CF3, -OCF 3, -CH 2 F, -OCH 2 F, -CF 2 H, -OCF ₂ H, -OCH ₃ or -CH ₃ substituted; (b) one or more -CH ₂ - in the cyclic structure may each independently be -O-, -SiH ₂ -, -S- or -CO-substitution, provided that the heteroatoms are not directly linked to each other; (C) in the cyclic structure, one or more -CH- in the aromatic ring structure may each be independently substituted by N; (d) the ring One or more of the structures Can be independently Substituted; Z ₁ represents -CF ₂ O-, -CH ₂ O-, -CH ₂ CH ₂ -, -CF ₂ CH ₂ -, -C ₂ F ₄ -, -(CH ₂ ) ₄ -, -C ₄ F ₈ -, -OCF ₂ CF ₂ O-, -CF ₂ CF ₂ CF ₂ O-, -CH ₂ CH ₂ CF ₂ O-, -OCF ₂ CF ₂ CF ₂ -, -CH ₂ CF ₂ OCH ₂ -, - CH=CHCH ₂ CH ₂ -, -C ₂ H ₄ OCH ₂ -, -CH ₂ CH=CHCH ₂ -, -OCH ₂ CH ₂ CH ₂ - or a single bond; Z ₂ , Z ₃ , and Z ₄ are the same or Different, each independently represents a single bond, -COO-, -CF ₂ O-, -CH ₂ O-, -CH ₂ CH ₂ -, -CF ₂ CH ₂ -, -CF=CF-, -CH=CH- , -CH=CF-, -C ₂ F ₄ -, -(CH ₂ ) ₄ -, -C ₄ F ₈ -, -OCF ₂ CF ₂ O-, -CF ₂ CF ₂ CF ₂ O-, -CH ₂ CH ₂ CF ₂ O-, -OCF ₂ CF ₂ CF ₂ -, -CH ₂ CF ₂ OCH ₂ -, -CH=CHCF ₂ O-, -CF ₂ OCH=CH-, -CF ₂ OCF=CH-, - CF ₂ OCH=CF-, -CF=CFCF ₂ O-, -CH=CFCF ₂ O-, -CF ₂ OCF=CF-, -CH=CHCH ₂ CH ₂ -, -C ₂ H ₄ OCH ₂ -, - CH ₂ CH=CHCH ₂ -, -OCH ₂ CH ₂ CH ₂ -, -CF=CF-CF=CF-, -C≡C-CF=CF-, -C≡C-CF=CF-C≡C- , -CF=CF-C≡C-CF=CF-, -C≡C-CF ₂ O- or -C≡C-, wherein any one of Z ₂ , Z ₃ , and Z ₄ -CH ₂ - can be independently substituted by -SiH ₂ -; m, n And p are the same or different, each independently represents 0, 1 or 2, when m is 2, two Z ₂ and two A ₂ are the same or different; when n is 2, two Z ₃ and two A ₃ are each the same or different; when p is 2, two Z ₄ and two A ₄ are each the same or different.

Another object of the present invention is to provide a synthesis method for synthesizing the liquid crystal compound of the formula (I).

Thus, the method for synthesizing the liquid crystal compound of the formula (I) of the present invention comprises the following steps:

Add sodium hydride to the dimethyl hydrazine solution, then add trimethyl iodine The hydrazine is heated, and then the compound of the formula (III) dissolved in dimethyl hydrazine is added to obtain a compound of the formula (IV); the tetrahydrofuran solution of the compound of the formula (IV) is added dropwise to the lithium-naphthalene-magnesium chloride. The prepared active magnesium reagent is further reacted with a compound of the formula (V) at a low temperature to obtain a compound of the formula (VI); the compound of the formula (VI) is further decomposed with trimethylchloroantane under the catalysis of trifluoroacetic acid. Hydroxyl group to give a compound of the formula (I).

R' ₁ -COOR ₅ (V)

R' ₁ is the same as R ₁ and R ₅ represents -CH ₃ or -CH ₂ CH ₃ .

The compound of the formula (III) is mainly synthesized by a commercially available intermediate or a known synthesis method, wherein the known synthesis methods include an esterification reaction, a Wittig reaction, a carbon-carbon cross-coupling reaction (Suzuki coupling, Negishi coupling, Heck coupling, Sonogashira coupling and transition metal catalysis and Grignard reagent cross-coupling reaction, etc.), reduction reaction, oxidation reaction and substitution reaction.

The compound of the formula (V) is mainly synthesized by a commercially available intermediate or a known synthesis method, wherein the known synthesis methods include, Wittig reaction, transition metal catalyzed Grignard reagent cross-coupling reaction, reduction reaction and ester Chemical reaction, etc.

The main reaction process is as follows:

(1) Add sodium hydride in anhydrous dimethyl hydrazine solvent under argon atmosphere, add trimethyl iodide iodide in batches, raise the temperature to 110 to 120 ° C, and add dimethyl amide of the compound of formula (III) dropwise. The hydrazine solution is reacted at 120 to 140 ° C for 30 minutes after the addition to obtain a compound of the formula (IV).

(2) References Journal of the American Chemical Society; 1995, 117 (20), 5429 to prepare an active magnesium reagent, and then add a solution of the compound of the formula (IV) in anhydrous tetrahydrofuran to the prepared activity by a syringe under argon atmosphere. In the magnesium reagent, stir at room temperature (25 ± 3 ° C) for 4 hours, add appropriate amount of tetrahydrofuran, let stand for stratification, transfer the supernatant into a dry and clean three-necked flask, and cool the argon atmosphere to -78 To a solution of the compound of the formula (V) in tetrahydrofuran at -85 ° C, after stirring, stir at -78 to -85 ° C for 1 to 2 hours, warm to room temperature (25 ± 3 ° C), and then heat to reflux 1 to 3 The compound of the formula (VI) is obtained in an hour.

(3) The compound of the formula (VI) is dissolved in dichloromethane, trifluoroacetic acid is added, trimethylchloromethane is added dropwise with stirring, and stirred at room temperature (25 ± 3 ° C) for 12 to 24 hours to obtain the formula ( I) Compound.

It is still another object of the present invention to provide a liquid crystal composition comprising the liquid crystal compound.

Thus, the liquid crystal composition of the present invention comprises one or more liquid crystal compounds of the formula (I).

Still another object of the present invention is to provide an application of the liquid crystal composition in a liquid crystal element, which is applicable to a liquid crystal element containing a liquid crystal medium.

Thus, the liquid crystal display of the present invention comprises a liquid crystal composition as described above.

The effect of the present invention is that the liquid crystal compound of the formula (I) having a hexahydroindole ring structure of the present invention has a novel structure and has a low viscosity, a large optical anisotropy, and a large dielectric anisotropy. The liquid crystal composition of the present invention has the effect of using a liquid crystal compound of the formula (I), and can be applied to display modes such as TN, STN, TFT, VA, ECB, OCB, LCP, PDLC, BiNem, LC LENS, FFS, and IPS. Liquid crystal element.

The contents of the present invention will be described in detail below:

Preferably, R ₁ represents -H, -F, a straight or branched alkyl or alkoxy group having from 1 to 10 carbon atoms which is substituted or unsubstituted with at least one halogen, wherein at least R _{1 is} at least One -CH ₂ - may be independently independently -O-, -S-, -SiH ₂ -, -CH=CH-, -C≡C-, -CF=CF-, -CH=CF-, -COO- Or -OCO-substitution, provided that the heteroatoms are not directly connected to each other, and the O, S and Si atoms are not directly connected to the ring, and R ₂ represents -H, -F, -Cl, -CN, -NCS, a straight or branched alkyl or alkoxy group having from 1 to 10 carbon atoms which is substituted or unsubstituted with at least one halogen, wherein at least one -CH ₂ - in the R ₂ may be independently taken - O-, -CH=CH-, -C≡C-, -CF=CF-, -CH=CF-, Or -COO-substitution, provided that the heteroatoms are not directly connected to each other.

Preferably, ring A ₁ represents , , , , , ,or Ring structure, rings A ₂ , A ₃ and A ₄ are the same or different and each independently represents , , , or The ring structure.

More preferably, the ring A ₁ represents , , , , or Ring structure, rings A ₂ , A ₃ and A ₄ are the same or different and each independently represents , , , , , or The ring structure.

Preferably, Z ₁ represents -CF ₂ O-, -CH ₂ O-, -CH ₂ CH ₂ -, -CF ₂ CH ₂ -, -C ₂ F ₄ -, -(CH ₂ ) ₄ -, -CH ₂ CH ₂ CF ₂ O-, -CH=CHCH ₂ CH ₂ -, -C ₂ H ₄ OCH ₂ -, -CH ₂ CH=CHCH ₂ -, -OCH ₂ CH ₂ CH ₂ - or a single bond, Z ₂ , Z ₃ and Z ₄ are the same or different and each independently represents -COO-, -CF ₂ O-, -CH ₂ O-, -CH ₂ CH ₂ -, -CF=CF-, -CH=CH-, - C ₂ F ₄ -, -(CH ₂ ) ₄ -, -C ₄ F ₈ -, -OCF ₂ CF ₂ O-, -CH ₂ CH ₂ CF ₂ O-, -CF=CFCF ₂ O-, -C ₂ H ₄ OCH ₂ -, -OCH ₂ CH ₂ CH ₂ -, -C≡C- or a single bond.

More preferably, Z ₁ represents -CF ₂ O-, -CH ₂ O-, -CH ₂ CH ₂ -, -CF ₂ CH ₂ -, -C ₂ F ₄ -, -(CH ₂ ) ₄ -, -CH ₂ CH ₂ CF ₂ O-, -CH=CHCH ₂ CH ₂ -, -C ₂ H ₄ OCH ₂ -, -CH ₂ CH=CHCH ₂ -, -OCH ₂ CH ₂ CH ₂ - or a single bond, Z ₂ , Z ₃ and Z ₄ are the same or different and each independently represents -COO-, -CF ₂ O-, -CH ₂ O-, -CH ₂ CH ₂ -, -CF=CF-, -CH=CH-, - C ₂ F ₄ -, -(CH ₂ ) ₄ -, -C ₄ F ₈ -, -OCF ₂ CF ₂ O-, -CF=CFCF ₂ O-, -C≡C- or a single bond.

Preferably, m, n and p are the same or different, each independently representing 0, 1 or 2, and 0 m+n+p 4.

Preferably, the liquid crystal compound of the formula (I) is selected from the group consisting of: Wherein, L ₁ to L ₄ are the same or different, each independently represents -H, -F or -CH ₃ , and L ₅ to L ₁₆ are the same or different, each independently expressing the formula -H, -F, -OCF ₂ H , -CH ₃ , -OCH ₃ , -OCF ₃ or -CF ₃ .

Preferably, the liquid crystal composition comprises from 1 to 5 liquid crystal compounds of the formula (I).

Preferably, the liquid crystal composition comprises 2 to 4 kinds of the general formula (I) Liquid crystal compound.

In the liquid crystal composition of the present invention, the component other than the general formula (I) may be a conventional liquid crystal compound, that is, it can be mixed in a pure state or with other components to form a liquid crystal composition. Some such compounds are mentioned, for example, in DE 1804894 and CN1158602A.

Preferably, the liquid crystal composition further comprises at least one liquid crystal compound of the formula (II):

Wherein R ₃ and R ₄ are the same or different and each independently represents -H, -F, -Cl, -CN, -NCS, -SCN, -OCN, -NCO, -OCH=CF ₂ , and has 1 to 20 a linear or branched alkyl or alkoxy group having one carbon atom substituted by at least one halogen or unsubstituted, or a linear or branched olefin having 2 to 20 carbon atoms substituted or unsubstituted with at least one halogen Or an alkenyloxy group, wherein at least one of the R ₃ and the R ₄ -CH ₂ - may be independently independently -O-, -S-, -SiH ₂ -, -CH=CH-, -C≡ C-, -CF=CF-, -CH=CF-, , -COO- or -OCO-, provided that the heteroatoms are not directly connected to each _{other; B 1, B 2, B} 3 and B ₄ are the same or different, each independently represent a , , , , indane-2,5-diyl, acridine-1,4-diyl, naphthalene-2,6-diyl, decahydronaphthalene-2,6-diyl or 1,2,3,4-tetra Hydronaphthalene-2,6-diyl, of which One or two of the non-adjacent -CH ₂ - may be independently substituted by -O- or -S-, Any of the above H can be independently replaced by F, which One or two non-adjacent -CH- of each may be independently replaced by N, One or more hydrogen atoms may be independently substituted by F, cyano or Cl, One or two non-adjacent -CH ₂ - may be independently replaced by O, One or more hydrogen atoms may be independently substituted by F; Y ₁ , Y ₂ and Y ₃ are the same or different and each independently represents -OCO-, -COO-, -CF ₂ O-, -CH ₂ O -, -OCH ₂ -, -CH ₂ CH ₂ -, -CF ₂ CH ₂ -, -CF=CF-, -CH=CH-, -CH(CH ₃ )CH ₂ -, -CH ₂ CH (CH ₃ )-, -(CH ₂ ) ₃ O-, -O(CH ₂ ) ₃ -, -COS-, -SCO-, -CH=CF-, -C ₂ F ₄ -, -(CH ₂ ) ₄ -, -C ₄ F ₈ -, -OCF ₂ CF ₂ O-, -CF ₂ CF ₂ CF ₂ O-, -CH ₂ CH ₂ CF ₂ O-, -CH ₂ CF ₂ OCH ₂ -, -CH=CHCF ₂ O -, -CF ₂ OCH=CH-, -CF ₂ OCF=CH-, -CF ₂ OCH=CF-, -CF=CFCF ₂ O-, -CF ₂ OCF=CF-, -CH=CHCH ₂ CH ₂ - , -C ₂ H ₄ OCH ₂ -, -CH ₂ CH=CHCH ₂ -, -OCH ₂ CH ₂ CH ₂ -, -CF=CF-CF=CF-, -C≡C-CF=CF-, -C ≡C-CF=CF-C≡C-, -CF=CF-C≡C-CF=CF-, -C≡C-CF ₂ O-, -C≡C- or a single bond, wherein, in the Y Any one of ₁ and Y ₂ -CH ₂ - may be independently substituted by -SiH ₂ -; a, b and c are the same or different, each independently representing 0, 1 or 2, when a is 2, two B ₁ and two Y ₁ are each the same or different; when b is, each two of the same or different and two the Y ₂ B _2; when c is 2, And a two Y ₃ B ₃ are each the same or different.

Preferably, the liquid crystal compound is selected from the group consisting of:

Preferably, the liquid crystal compound of the formula (I) is used in an amount ranging from 5 to 50% by weight based on 100% by weight of the total weight of the liquid crystal composition, and the liquid crystal compound of the formula (II) is used in an amount ranging from 50 to 95wt%.

Preferably, the liquid crystal compound of the formula (I) is used in an amount ranging from 10 to 30% by weight based on 100% by weight of the total weight of the liquid crystal composition, and the liquid crystal compound of the formula (II) is used in an amount ranging from 70 to 90wt%.

The invention will now be described in connection with specific embodiments. It is to be understood that the following examples are illustrative of the invention and are not intended to limit the invention. Other combinations and various modifications within the inventive concept can be made without departing from the spirit or scope of the invention.

For ease of expression, in the following examples, the group structure of the liquid crystal compound is represented by the codes listed in Table 1: Take a compound of the following structural formula as an example:

The structural formula is expressed as the code listed in Table 1, and can be expressed as: 3PUQUF.

[Example 1]

The synthetic steps for the preparation of the compound HCLC-14D are as follows:

Among them, HCLC-14D-6 is synthesized by reference EP1160251.

The specific synthetic steps of HCLC-14D are as follows:

(1). Synthesis of HCLC-14D-5

Under a nitrogen atmosphere, add 68g of HCLC-14D-6, 0.48g of Mg and 400mL of anhydrous THF to a dry 1L three-necked flask. Add 126mL of 2mol/L isopropylmagnesium chloride in THF at a temperature below 20°C. After reacting at 20 ° C for 2 hours, a solution of 36.5 g of 1,4 cyclohexanedione in 100 mL of THF was added dropwise at 50 ° C or lower. After the completion of the dropwise addition, the mixture was refluxed for 2 hours, and 200 mL of the solution was gradually added to the reaction solution. After the ammonium chloride solution was separated and the aqueous phase was extracted twice with 100 mL of ethyl acetate, the organic phase was combined, washed three times with saturated sodium chloride solution, dried over 100 g of anhydrous sodium sulfate, and evaporated to dryness 92.4 g of a yellow solid was obtained, and the crude product was subjected to column chromatography using petroleum ether (PE): ethyl acetate = 6:1, and the product was collected, and the solvent was evaporated to dryness by a rotary concentrator to obtain 84.5. g light yellow solid.

The pale yellow solid was added to a 500 mL three-necked flask, and then 4.2 g of p-Toluenesulfonic acid monohydrate, 300 mL of toluene and 15 g of ethylene glycol were added, and a reflux water-packing device was installed. The mixture was refluxed under nitrogen for 4 hours. After the reaction mixture was cooled to room temperature (25 ± 3 ° C), 100 mL of saturated sodium bicarbonate solution was added, and the organic phase was washed twice with 200 mL of deionized water. The solvent was evaporated to dryness under reduced pressure using a rotary concentrator, and then recrystallized twice with 200 mL of anhydrous ethanol and 100 mL of petroleum ether to give product HCLC-14D-5 75.2 g, purity: 99.4%, yield 92.4%.

(2). Synthesis of HCLC-14D-4

75.2 g of HCLC-14D-5 solution dissolved in 400 mL of toluene and 150 mL of ethanol was added to a 1 L high pressure hydrogenator, and 5 g of 5% Pd/C was added thereto, and the high pressure hydrogenation kettle was sealed, and 5 to 6 were replaced with nitrogen and hydrogen, respectively. The catalyst was hydrogenated at 1.5 MPa for 6 hours at room temperature (25 ± 3 ° C), monitored by GC until no material remained, and the reaction liquid was filtered to remove the catalyst. The filtrate was evaporated to dryness with a rotary concentrator to obtain 75.8 g of white. The solid was recrystallized from 200 mL of anhydrous ethanol and 100 mL of petroleum ether to give the product HCLC-14D-4 74.5 g, purity: 99.6%, yield 98.5%.

(3). Synthesis of HCLC-14D-3

Add 74.5g of HCLC-14D-4, 380mL of anhydrous formic acid and 8mL of deionized water dissolved in 200mL of toluene in a 1L three-necked flask, react at room temperature (25±3 °C) for 24 hours, and add the reaction solution to 400 mL of saturated sodium chloride. The liquid phase was separated and extracted with 100 mL of toluene four times. All the organic phases were combined, washed twice with deionized water, twice with saturated sodium bicarbonate solution, and the organic phase was evaporated to dryness with a rotary concentrator. 66.4 g of a pale yellow solid were obtained, which was recrystallized from 200 mL of anhydrous ethanol and 100 mL of toluene to afford white solid HCLC-14D-3 60.5 g, purity: 99.7%, yield 92.3%.

Synthesis of HCLC-14D-2

46.8 g of sodium hydride was added to 1 L of anhydrous dimethyl hydrazine solvent under argon atmosphere, and 85.8 g of trimethyl iodide iodide was added in portions. After the addition, the temperature was raised to 110 to 120 ° C, and 41.7 g of HCLC-14D was added dropwise. -3 of 100 mL of dimethyl hydrazine solution, after the addition, react at 120 to 140 ° C for 30 minutes, naturally cool to room temperature (25 ± 3 ° C), and slowly add the reaction solution to 1.5 L of ice brine under ice bath. Then, 400 mL of ethyl acetate was further added and stirred for three times. The organic phase was washed three times with 400 mL of a saturated sodium chloride solution, dried over anhydrous sodium sulfate (80 g), and evaporated to dryness. The ether extract was subjected to column chromatography, and the product chromatography liquid was collected, and the solvent was evaporated under reduced pressure using a rotary concentrator to obtain 35.2 g of pale yellow solid, which was then recrystallized three times with 100 mL of anhydrous ethanol to obtain 24.3 g of white solid HCLC- 14-2, purity: 99.2%, yield 56.5%.

(5). Synthesis of HCLC-14D-1

Under dry atmosphere, add 13.87g anhydrous magnesium chloride, 2.1g lithium strip, 5.87g naphthalene, 470mL anhydrous tetrahydrofuran and dry clean magnet in dry and clean three-necked flask. At room temperature (25±3°C) under argon atmosphere. Stir for 3.5 hours, add 300 mL of anhydrous tetrahydrofuran, stop stirring, let stand for 2 hours, pour 650 mL of solution under argon atmosphere, and then add 24.3 g of HCLC-14D-2 in 450 mL of anhydrous tetrahydrofuran solution with a syringe under argon atmosphere. Stir for 4 hours under temperature, then add 300 mL of tetrahydrofuran with a syringe, stop stirring, and let stand for 3.5 hours; transfer the supernatant to a dry and clean three-necked flask, and cool the argon atmosphere to -78 to -85 °C, drip 11.1g of a solution of ethyl propionate in 100 mL of tetrahydrofuran. After the addition, the mixture was stirred at -78 to -85 ° C for 1.5 hours, warmed to room temperature (25 ± 3 ° C), and heated under reflux for 2 hours. The reaction solution was cooled to room temperature (25±3 ° C), and the reaction solution was slowly added to 100 mL of 2 mol/L concentrated hydrochloric acid, and then added with 300 mL of ethyl acetate, and the mixture was separated, and the aqueous phase was extracted twice with 100 mL of ethyl acetate. All the organic phases were combined, washed with saturated sodium chloride solution three times, dried over 100 g of anhydrous sodium sulfate, and evaporated to dryness with a rotary concentrator to give 29.2 g of pale yellow solid, and the crude product was recrystallized twice with 80 mL of petroleum ether. White solid HCLC-14D-1 27.1 g. Purity: 98.5%, yield 94.5%.

(6). Synthesis of HCLC-14D

To a 500 mL three-necked flask, 27.1 g of HCLC-14D-1, 300 mL of dichloromethane and 30 mL of trifluoroacetic acid were added, and 13 mL of trimethylchloromethane was added dropwise with stirring, and the mixture was stirred at room temperature (25 ± 3 ° C) for 12 hours to react. The solution was poured into 200 mL of saturated sodium bicarbonate solution, and the organic phase was washed twice with 100 mL of deionized water, dried over 40 g of anhydrous sodium sulfate, and evaporated to dryness. The solid was recrystallized three times from 100 mL of EtOAc (EtOAc).

_{1H NMR (300MHz, CDCl 3)} δ 7.75 (dd, J = 14.9,10.0Hz, 1H), 7.47-7.16 (m, 4H), 3.12-2.94 (m, 1H), 2.47-2.32 (m, 1H), 2.32-2.21(m,1H),2.13-1.76(m,7H),1.76-1.48(m,4H),0.93(t, J = 13.3Hz, 3H).

[Embodiment 2]

The synthetic steps for the preparation of the compound HCLC-14F are as follows: Among them, HCLC-14F-5 is synthesized by reference EP2206695; HCLC-14F-4 is synthesized by the Journal of Organic Chemistry, 1994, 59(7), pp1855-1862.

The specific synthetic steps of HCLC-14F are as follows:

(1). Synthesis of HCLC-14F-3

In a 500 mL dry clean single-necked flask, add 13.2 g of HCLC-14F-5, 12.6 g of HCLC-14F-4, 10.6 g of anhydrous sodium carbonate, 50 mL of deionized water, 150 mL of toluene and 50 mL of absolute ethanol, and replace the venting with argon. Thereafter, 1 g of Pd[P(Ph) ₃ ] _{4 was added} . The mixture was heated to reflux for 22 hours under an argon atmosphere, and the reaction liquid was cooled and separated. The organic phase was subjected to column chromatography using 8:1 petroleum ether and ethyl acetate extracts, and the solvent was evaporated to dryness with a rotary concentrator. 18.7 g of a pale yellow solid, which was recrystallized from 20 mL of toluene and 50 mL of anhydrous ethanol to give 12.8 g of white solid HCLC-14F-3, purity: 99.7%, yield 65.4%.

(2). Synthesis of HCLC-14F-2

Under an argon atmosphere, 11.7 g of sodium hydride was added to 250 mL of anhydrous dimethyl hydrazine solvent, and 21.5 g of trimethyl iodide iodide was added in portions. After the addition, the temperature was raised to 110 to 120 ° C, and 12.8 g of HCLC-14F was added dropwise. -3 of 50mL two The solution of yamidine is reacted at 120 to 140 ° C for 30 minutes, and then naturally cooled to room temperature (25 ± 3 ° C). The reaction solution is slowly added dropwise to 1 L of ice brine under ice bath, and then 200 mL of acetic acid is added. The ester was extracted three times with stirring, the organic phase was washed three times with 100 mL of saturated sodium chloride solution, dried over 80 g of anhydrous sodium sulfate, and the solvent was evaporated to dryness with a rotary concentrator to give 14.4 g of a yellow solid. Chromatography, the product chromatography solution was collected, and the solvent was evaporated to dryness with a rotary concentrator to give 12.7 g of pale yellow solid, and then recrystallized three times with 60 mL of anhydrous ethanol and 30 mL of petroleum ether to obtain 7.6 g of white solid HCLC-14F-2. , purity: 99.4%, yield 57.8%.

(3). Synthesis of HCLC-14F-1

Under an argon atmosphere, add 3.58g anhydrous magnesium chloride, 0.55g lithium strip, 1.5g naphthalene, 120mL anhydrous tetrahydrofuran and dry clean magnet in a dry and clean three-necked flask at room temperature (25±3°C) under argon atmosphere. Stir well for 3 hours, add 80 mL of anhydrous tetrahydrofuran, stop stirring, let stand for 2 hours, pour out 170 mL of solution under argon atmosphere, then add 7.6 g of HCLC-14F-2 in 120 mL of anhydrous tetrahydrofuran solution by syringe under argon atmosphere. Stir at temperature (25 ± 3 ° C) for 4 hours, then add 80 mL of tetrahydrofuran with a syringe, stop stirring, let stand for 3 hours; transfer the upper layer into a dry and clean three-necked flask, and cool the argon atmosphere to -78 to A solution of 2.9 g of ethyl propionate in 20 mL of tetrahydrofuran was added dropwise at -85 ° C. After the addition, the mixture was stirred at -78 to -85 ° C for 1 hour, warmed to room temperature (25 ± 3 ° C), and heated to reflux for 1 hour. The solution was cooled to room temperature (25 ± 3 ° C), and the reaction solution was slowly added to 20 mL of 2 mol/L concentrated hydrochloric acid, and then added with 100 mL of ethyl acetate, and the mixture was separated, and the aqueous phase was extracted twice with 50 mL of ethyl acetate. All organic phases are combined to saturate The sodium chloride solution was washed three times, dried over 20 g of anhydrous sodium sulfate, and the solvent was evaporated to dryness with a rotary concentrator to give 8.5 g of pale yellow solid. The crude product was recrystallized twice with 80 mL of petroleum ether to give white solid HCLC-14F-1 8g. Purity: 99.3%, yield 92.4%.

(4). Synthesis of HCLC-14F

8 g of HCLC-14F-1, 80 mL of dichloromethane and 8 mL of trifluoroacetic acid were added to a 250 mL three-necked flask, and 4 mL of trimethylchloromethane was added dropwise with stirring, and the mixture was stirred at room temperature (25 ± 3 ° C) for 12 hours to react. The solution was poured into 100 mL of saturated sodium bicarbonate solution, and the organic phase was washed twice with 50 mL of deionized water, dried over 10 g of anhydrous sodium sulfate, and evaporated to dryness. The crude product was recrystallized three times with 30 mL of ethanol and 10 mL of toluene to afford white solid HCLC-14F 5.8 g, purity: 99.9%, yield 75.3%.

¹ H NMR (300 MHz, CDCl ₃ ) δ 7.75 (dd, J =15.0, 10.0 Hz, 1H), 7.65-7.45 (m, 4H), 7.40-7.24 (m, 2H), 3.16-2.90 (m, 1H) , 2.61-2.18 (m, 3H), 2.17.1-36 (m, 17H), 1.36-1.11 (m, 5H), 1.10-0.81 (m, 8H).

The following Example 3 is a performance test result of the liquid crystal composition of the present invention:

The abbreviated codes for the test properties in the following examples are as follows:

[Example 3]

Table 2 shows the composition of HCLC-14D and HCLC-14F as liquid crystal compositions and the obtained performance parameters:

The above is only the preferred embodiment of the present invention, and the scope of the present invention is not limited thereto, that is, the simple equivalent changes and modifications made by the scope of the patent application and the patent specification of the present invention, All remain within the scope of the invention patent.

Claims (10)

A liquid crystal compound having the structure of the formula (I): Wherein R ₁ represents -H, -F, a straight or branched alkyl or alkoxy group having from 1 to 20 carbon atoms which is substituted or unsubstituted with at least one halogen, wherein at least R ₁ One -CH ₂ - may be independently substituted by -O-, -S- or -SiH ₂ -, provided that the heteroatoms are not directly bonded to each other, and the O, S and Si atoms are not directly bonded to the ring; R ₂ represents - H, -F, -Cl, -CN, -NCS, -SCN, -NCO, a linear or branched alkyl or alkoxy group having 1 to 20 carbon atoms substituted or unsubstituted with at least one halogen, wherein at least one -CH ₂ - in the R ₂ may be independently -O-, -S-, -SiH ₂ -, -CH=CH-, -C≡C-, -CF=CF-, or -CH=CF-substitution, provided that the heteroatoms are not directly linked to each other; A ₁ Express , or Ring structure; A ₂ , A ₃ and A ₄ are the same or different and each independently represents Ring structure; alternatively, the ring structure represented by A ₁ , A ₂ , A ₃ , and A ₄ conforms to at least one of the following (a), (b), (c), and (d): (a One or more hydrogen atoms in the cyclic structure may each independently be -D, -F, -Cl, -CN, -CF ₃ , -OCF ₃ , -CH ₂ F, -OCH ₂ F, -CF ₂ H, -OCF ₂ H, -OCH ₃ or -CH ₃ substituted; (b) one or more -CH ₂ - in the cyclic structure may each independently be -O-, -SiH ₂ -, -S- Or -CO-substitution, provided that the heteroatoms are not directly linked to each other; (C) in the cyclic structure, one or more -CH- in the aromatic ring structure may each be independently substituted by N; (d) the ring One or more of the structures Can be independently Substituted; Z ₁ represents -CF ₂ O-, -CH ₂ O-, -CH ₂ CH ₂ -, -CF ₂ CH ₂ -, -C ₂ F ₄ -, -(CH ₂ ) ₄ -, -C ₄ F ₈ -, -OCF ₂ CF ₂ O-, -CF ₂ CF ₂ CF ₂ O-, -CH ₂ CH ₂ CF ₂ O-, -OCF ₂ CF ₂ CF ₂ -, -CH ₂ CF ₂ OCH ₂ -, - C ₂ H ₄ OCH ₂ -, -OCH ₂ CH ₂ CH ₂ - or a single bond; Z ₂ , Z ₃ , and Z ₄ are the same or different and each independently represents a single bond, -CF ₂ O-, -CH ₂ O-, -CH ₂ CH ₂ -, -CF ₂ CH ₂ -, -CF=CF-, -CH=CH-, -CH=CF-, -C ₂ F ₄ -, -(CH ₂ ) ₄ -, -C ₄ F ₈ -, -OCF ₂ CF ₂ O-, -CF ₂ CF ₂ CF ₂ O-, -CH ₂ CH ₂ CF ₂ O-, -OCF ₂ CF ₂ CF ₂ -, -CH ₂ CF ₂ OCH ₂ -, -CH=CHCF ₂ O-, -CF ₂ OCH=CH-, -CF ₂ OCF=CH-, -CF ₂ OCH=CF-, -CF=CFCF ₂ O-, -CH=CFCF ₂ O- , -CF ₂ OCF=CF-, -CH=CHCH ₂ CH ₂ -, -C ₂ H ₄ OCH ₂ -, -CH ₂ CH=CHCH ₂ -, -OCH ₂ CH ₂ CH ₂ -, -CF=CF- CF=CF-, -C≡C-CF=CF-, -C≡C-CF=CF-C≡C-, -CF=CF-C≡C-CF=CF-, -C≡C-CF ₂ O- or -C≡C-, wherein any one of -Z ₂ , Z ₃ , and Z ₄ -CH ₂ - may be independently substituted by -SiH ₂ -; m, n and p are the same or different, Independent of each other Shows 0, 1 or 2, when m is 2, two Z are each the same _or different and the two A _2; when n is 2, two Z ₃ and two A ₃ are each the same or different; when p is 2. Two Z ₄ and two A ₄ are each the same or different. The liquid crystal compound according to claim 1, wherein 0 m+n+p 4. The liquid crystal compound according to claim 1, wherein the liquid crystal compound is selected from the group consisting of: Wherein, L ₁ to L ₄ are the same or different, each independently represents -H, -F or -CH ₃ , and L ₅ to L ₁₆ are the same or different, each independently expressing the formula -H, -F, -OCF ₂ H , -CH ₃ , -OCH ₃ , -OCF ₃ or -CF ₃ . A liquid crystal composition comprising at least one liquid crystal compound according to any one of claims 1 to 3. The liquid crystal composition according to claim 4, comprising one to five liquid crystal compounds according to any one of claims 1 to 3. The liquid crystal composition according to claim 4, which further comprises at least one liquid crystal compound of the formula (II): Wherein R ₃ and R ₄ are the same or different and each independently represents -H, -F, -Cl, -CN, -OCH=CF ₂ , having 1 to 20 carbon atoms substituted or unsubstituted with at least one halogen a linear or branched alkyl or alkoxy group, a linear or branched alkenyl or alkenyloxy group having 2 to 20 carbon atoms substituted or unsubstituted with at least one halogen, wherein, in the R ₃ R ₄ and the at least one -CH ₂ - may be each independently substituted with -O -, - S -, - SiH 2 -, - CH = CH -, - C≡C -, - CF = CF- or -CH = CF- substituent, provided that the heteroatoms are not directly connected to each _{other; B 1, B 2, B} 3 and B ₄ are the same or different, each independently represent a , Or naphthalene-2,6-diyl, wherein One or two of the non-adjacent -CH ₂ - may be independently substituted by -O- or -S-, Any of the above H can be independently replaced by F, which One or two non-adjacent -CH- of each may be independently replaced by N, One or more hydrogen atoms may be independently substituted by F, cyano or Cl; Y ₁ , Y ₂ and Y ₃ are the same or different and each independently represents -OCO-, -COO-, -CF ₂ O- , -CH ₂ O-, -OCH ₂ -, -CH ₂ CH ₂ -, -CF ₂ CH ₂ -, -CF=CF-, -CH=CH-, -CH(CH ₃ )CH ₂ -, -CH ₂ CH(CH ₃ )-, -(CH ₂ ) ₃ O-, -O(CH ₂ ) ₃ -, -COS-, -SCO-, -CH=CF-, -C ₂ F ₄ -, -(CH ₂ ) ₄ -, -C ₄ F ₈ -, -OCF ₂ CF ₂ O-, -CF ₂ CF ₂ CF ₂ O-, -CH ₂ CH ₂ CF ₂ O-, -CH ₂ CF ₂ OCH ₂ -, - CH=CHCF ₂ O-, -CF ₂ OCH=CH-, -CF ₂ OCF=CH-, -CF ₂ OCH=CF-, -CF=CFCF ₂ O-, -CF ₂ OCF=CF-, -CH= CHCH ₂ CH ₂ -, -C ₂ H ₄ OCH ₂ -, -CH ₂ CH=CHCH ₂ -, -OCH ₂ CH ₂ CH ₂ -, -CF=CF-CF=CF-, -C≡C-CF= CF-, -C≡C-CF=CF-C≡C-, -CF=CF-C≡C-CF=CF-, -C≡C-CF ₂ O-, -C≡C- or single bond, Wherein, any one of Y ₁ and Y ₂ -CH ₂ - may be independently substituted by -SiH ₂ -; a, b and c are the same or different, each independently representing 0, 1 or 2, when a is 2, two B ₁ and two Y ₁ are the same or different; when b is 2, two B ₂ and two Y ₂ are the same or different When c is 2, two B ₃ and two Y ₃ are the same or different. The liquid crystal composition according to claim 6, wherein the liquid crystal compound of the formula (II) is selected from the group consisting of: The liquid crystal composition according to claim 6, wherein the liquid crystal compound of the formula (I) is used in an amount ranging from 5 to 50% by weight based on 100% by weight of the total weight of the liquid crystal composition, and the formula (II) The liquid crystal compound is used in an amount ranging from 50 to 95% by weight. The liquid crystal composition according to claim 8, wherein the (I) liquid crystal compound is used in an amount ranging from 10 to 30% by weight based on 100% by weight of the total of the liquid crystal composition, and the liquid crystal of the formula (II) The compound is used in an amount ranging from 70 to 90% by weight. A liquid crystal display comprising as claimed in any one of claims 4 to 9 A liquid crystal composition as described.