JP2674190B2 - Liquid crystal material - Google Patents

Description

TECHNICAL FIELD The present invention relates to a liquid crystal material, and more specifically,
The present invention relates to a novel liquid crystal material composed of a diaryl thiadiazolo heterocyclic compound having a specific structure.

[Prior Art] Conventionally, compounds having various structures have been known as liquid crystal materials, but no liquid crystal materials composed of diaryl thiadiazolo heterocyclic compounds have been reported.

On the other hand, as a diaryl thiadiazoloheterocyclic compound, "Dye and drug" vol.33, No.12,338-348 (198
8) ”describes the following compounds.

However, the above-mentioned publicly-known documents do not describe at all the possibility of using such a compound as a liquid crystal material.

JP-A-62-185757 discloses, as a coloring material for organic polymers, a diaryl thiadiazoloheterocycle having the following structure in which hydrogen bonded to the 6-position carbon of the thiadiazoloheterocycle is replaced with a specific group X. System compounds are described.

(In the formula, X represents an optionally substituted phenyl group, an alkoxycarbonyl group or a cyano group, and R ^a , R ^b ,
R ^c and R ^d are a hydrogen atom, an alkyl group, an acylamino group, an alkoxy group, a halogen atom or Represents R ^e and R ^f are hydrogen atoms, which may be substituted.
Alkyl C ₁ -C _20, an aryl group or a cyclohexyl group. [Problems to be Solved by the Invention] In recent years, the fields of application of liquid crystal materials have been expanding more and more, and there is a strong demand for the development of novel high-performance liquid crystal materials that have never existed before.

The present invention has been made in view of the above conventional circumstances, and an object of the present invention is to provide a novel liquid crystal material having remarkably excellent liquid crystal characteristics.

[Means for Solving the Problems] The liquid crystal material of the present invention has the general formula [I] (In the formula, Z represents CH or N, R ¹ and R ² are alkyl groups,
It represents a cycloalkyl group, a bicycloalkyl group, a cycloalkyloxy group, an alkoxy group or an alkylcarbonyloxy group. ) Is a diaryl thiadiazolo heterocyclic compound represented by

That is, the inventors of the present invention conducted extensive studies for the purpose of providing a novel liquid crystal material, and found that the above-mentioned JP-A-62-62
The 6-position-substituted compounds described in -185757 do not exhibit liquid crystallinity at all, but include 6-position-unsubstituted, specific diarylthiadia compounds including the compounds described in the above-mentioned known document "Dyes and Chemicals". It was found that zoroheterocyclic compounds exhibit remarkable liquid crystallinity. The present invention has been achieved based on the above findings.

 Hereinafter, the present invention will be described in detail.

The liquid crystal material of the present invention comprises a diaryl thiadiazolo heterocyclic compound represented by the above general formula [I]. In the above general formula [I], R ¹ and R ² are alkyl groups, Specifically, methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group,
C ₁ -C ₂₀ alkyl group such as octyl group; cycloalkyl group such as cyclohexyl group, cyclopentyl group, cycloheptyl group; bicycloalkyl group such as bicyclooctyl group; cycloalkyloxy group such as cyclohexyloxy group, cyclopentyloxy group An alkoxy group, specifically a C _{1 to} C ₂₀ alkoxy group such as a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, a hexyloxy group, a heptyloxy group, an octyloxy group; an alkylcarbonyloxy group , Specifically, a methylcarbonyloxy group, an ethylcarbonyloxy group, a propylcarbonyloxy group, a butylcarbonyloxy group, etc.
Examples thereof include C _{1 to} C ₂₀ alkylcarbonyloxy groups.

Of these, R ¹ and R ² are C _{1 to} C ₁₂ alkyl groups,
A C ₁ -C ₁₂ alkoxy group, a cyclohexyl group, and a bicyclooctyl group are particularly preferable.

Among the diaryl thiadiazolo heterocyclic compounds of the present invention represented by the above general formula [I], those in which Z is CH are
For example, it can be manufactured as follows.

That is, the following general formula [II] (In the formula, R ¹ and R ² are the same as defined above.) And the following structural formula [III] H ₂ NCH ₂ COOR ³ ... [III] (In the formula, R ³ represents an alkyl group.) By reacting with a glycine alkyl ester represented by
The following general formula [IV] (In the formula, R ¹ , R ² and R ³ are the same as defined above.) An alkyl ester derivative represented by the following formula is obtained, and this is hydrolyzed in an alkaline alcohol solution to give the following general formula [V]: (In the formula, R ¹ and R ² are the same as those defined above.) A compound of the present invention can be produced by obtaining a carboxylic acid derivative and then decarboxylating the carboxylic acid derivative.

On the other hand, among the diaryl thiadiazoloheterocyclic compounds of the present invention represented by the general formula [I], those in which Z is N can be produced, for example, as follows.

That is, the compound of the present invention is obtained by reacting the compound represented by the general formula [II] with the hydrazine hydrate represented by the following structural formula [VI] NH ₂ NH ₂ .H ₂ O ... [VI]. It can be manufactured.

[Operation] According to the specific diarylthiadiazoloheterocyclic compound of the present invention, a novel high-performance liquid crystal material comprising a diarylthiadiazoloheterocyclic compound, which has never existed before, is provided.

[Examples] Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to the following examples as long as the gist thereof is not exceeded.

Example 1 Synthesis Method [A] Ethyl-4,7-di (4-ethoxyphenyl)-
1,2,5-thiadiazolo [3,4-c] pyridine-6-carboxylate ( 2b ) and butyl-4,7-di (4-ethoxyphenyl) -1,2,5-thiadiazolo [3,4- c] Synthesis of pyridine-6-carboxylate ( 3b ).

3,4-Di (4-ethoxybenzoyl) -1,2,5-thiadiazole ( 1b ) (0.5g, 1.3mmol) and glycine ethyl ester hydrochloride (0.6g, 3.9mmol) in butanol (60ml)
After heating under reflux for 72 hours, the reaction solution was poured into water, extracted with 50 ml of benzene, and the solvent was evaporated under reduced pressure. The obtained residue is subjected to column chromatography (silica gel, Wakogel C-300).
First, orange butyl-4,7-di (4-ethoxyphenyl) -1,2,5-thiadiazolo [3,4-c] pyridine-6-carboxylate ( 3b ), then yellow Ethyl-4,7-di (4-ethoxyphenyl) -1,2,5-thiadiazolo [3,4-c] pyridine-6-carboxylate ( 2
b ) got. Both were recrystallized from hexane ( 3b ) (0.0
6 g, 1.2 mmol, yield 10%) and ( 2b ) (0.50 g, 1.1 mmol, yield 80%) were obtained. Furthermore, unreacted ( 1b ) (0.02g, 4%)
I got

Physical properties ( 2b ) Melting point: 142-143 ° C Yellow prism-like crystal Mass spectrum: m / e 449 (M +) IR spectrum: λ 3000,1720,1600,1515,1440,1380,124
. 0,1170,1150,1040,1020,890,840,800,720cm ^{-1 1} H-NMR spectrum _{(CDCl 3): δ 1.12 (} 3H, t, CH 3), 1.44 (6H, t, CH 3), 4.08 (2H, q, C
H ₂ ), 4.12 (2H, q, CH ₂ ), 4.24 (2H, q, CH ₂ ), 7.00 (2H, m,
ArH), 7.20 (2H, m, ArH), 7.52 (2H, m, ArH), 8.68 (2H,
m, ArH) ( 3b ) Melting point: 85-87 ° C Orange prism crystal Mass spectrum: m / e 477 (M +) IR spectrum: λ 2950,1720,1600,1520,1440,1390,131
. 0,1250,1180,1160,1040,920,900,840,410,760cm ^{-1 1} H-NMR spectrum _{(CDCl 3): δ 0.80 (} 3H, t, CH 3), 1.36 (4H, m, CH 2), 1.44 (6H, t, C
H ₃ ), 4.08 (2H, q, CH ₂ ), 4.12 (2H, t, CH ₂ ), 4.16 (2H, q,
CH ₂ ), 7.00 (2H, m, ArH), 7.06 (2H, m, ArH), 7.52 (2H,
m, ArH), 8.68 (2H, m, ArH) [B] 4,7-Di (4-ethoxyphenyl) -1,2,5-thiadiazolo [3,4-c] pyridine-6-carboxylic acid ( 4
b ) Synthesis of.

An ethanol solution (60 ml) of sodium hydroxide (0.30 g, 7.5 mmol) and ( 2b ) (0.30 g, 0.7 mmol) obtained in the above [A] was heated under reflux for 3 hours, and then the reaction solution was mixed with water (50 ml). Injected inside. Acidify with concentrated hydrochloric acid, filter the resulting yellow crystals and recrystallize from ethanol to give 4,7-di (4-ethoxyphenyl) -1,2,5-thiadiazolo [3,4-c] pyridine-6-. A carboxylic acid ( 4b ) (0.26 g, 0.6 mmol, yield 93%) was obtained.

Physical properties ( 4b ) Melting point: 185-189 ° C (decomposition) Orange needle crystal Mass spectrum: m / e 421 (M + -1) IR spectrum: λ 3500,2980,1769,1707,1606,1520,145
. 2,1235,1179,1132,1046,990,891,837cm ^{-1 1} H-NMR spectrum _{(CDCl 3): δ 1.44 (} 3H, t, CH 3), 1.48 (3H, t, CH 3), 4.10 (2H, q, C
H ₂ ), 4.12 (2H, q, CH ₂ ), 7.06 (4H, m, ArH), 7.44 (2H, m,
ArH), 8.60 (2H, m, ArH) Synthesis of [C] 4,7-di (4-ethoxyphenyl) -1,2,5-thiadiazolo [3,4-c] pyridine ( 5b ).

After heating ( 4b ) (0.14 g) obtained in the above [B] in a glass tube oven at 200 ° C. for 30 minutes, the reaction product was subjected to column chromatography (silica gel, Wakogel C-300), and from the dichloromethane fraction. The obtained product was recrystallized from a mixed solvent (1: 2) of methyl ethyl ketone and ethanol to give 4,7-di (4-ethoxyphenyl) -1,2,5-thiadiazolo [3,4-c] pyridine. ( 5b ) (0.09g, Yield 72
%).

Physical properties ( 5b ) Melting point: 192-194 ° C Yellow needle crystals (recrystallized from ethanol) Mass spectrum: m / e 377 (M +) IR spectrum: λ 2982,1607,1510,1456,1395,1251,117
. 9,1116,1046,923,887,840cm ^{-1 1} H-NMR spectrum _{(CDCl 3): δ 1.44 (} 6H, t, CH 3), 4.12 (2H, q, CH 2), 4,14 (2H, q, C
H ₂ ), 7.04 (4H, m, ArH), 7.92 (2H, m, ArH), 8.60 (2H, m,
ArH), 8.70 (1H, s, ArH) Liquid crystallinity The following structural formula obtained in [C] above 4,7-di (4-ethoxyphenyl) -1,2,5 represented by
The state of thermal phase change (DSC measurement) of thiadiazolo [3,4-c] pyridine ( 5b ) was as follows. In addition,
() Indicates ΔH (kcal / mol).

Example 2 Synthesis method [A] Ethyl-4,7-di (4-methoxyphenyl)-
1,2,5-thiadiazolo [3,4-c] pyridine-6-carboxylate ( 2a ) and butyl-4,7-di (4-methoxyphenyl) -1,2,5-thiadiazolo [3,4- c] Synthesis of pyridine-6-carboxylate ( 3 g ).

3,4-Di (4-methoxybenzoyl) -1,2,5-thiadiazole ( 1a ) (0.3 g, 0.8 mmol) and glycine ethyl ester hydrochloride (0.36 g, 2.5 mmol) in butanol (30 ml) 72 After heating for an hour, the same treatment as in [A] of Example 1 was carried out,
In addition to unreacted ( 1a ) (0.07g), ethyl-4,7-di (4
-Methoxyphenyl) -1,2,5-thiadiazolo [3,4-
c] pyridine-6-carboxylate ( 2a ) and butyl-
4,7-Di (4-methoxyphenyl) -1,2,5-thiadiazolo [3,4-c] pyridine-6-carboxylate ( 3a )
To give a mixture (0.21 g).

[B] 4,7-Di (4-methoxyphenyl) -1,2,5-thiadiazolo [3,4-c] pyridine-6-carboxylic acid ( 4
a ) Synthesis.

A mixture of ( 2a ) and ( 3a ) (0.
21 g) is not separated, but as it is in Example 1 [B].
4,7-di (4-methoxyphenyl) -1,2,5-thiadiazolo [3,4-c] pyridine-6
-Carboxylic acid ( 4a ) (0.14g) (orange powder) was obtained. The melting point of this product was 182-185 ° C.

Synthesis of [C] 4,7-di (4-methoxyphenyl) -1,2,5-thiadiazolo [3,4-c] pyridine ( 5a ).

The ( 4a ) (0.14 g) obtained in the above [B] was used as it was without recrystallization and treated in the same manner as in the [C] of Example 1 to obtain 4,7-di (4-methoxyphenyl)- 1,2,5-thiadiazolo [3,4-c] pyridine ( 5a ) (0.09g) was obtained.

Physical properties ( 5a ) Melting point: 185 ° C Orange prism crystals (recrystallized from a mixed solution of methyl ethyl ketone: ethanol = 1: 2) Mass spectrum: m / e 349 (M +) ¹ H-NMR spectrum (CDCl ₃ ): δ 3.48 (3H, s, OCH ₃ ), 3.85 (3H, s, OCH ₃ ), 7.20 (4H, m, Ar
H), 7.86 (2H, m, ArH), 8.60 (2H, m, ArH), 8.65 (1H, s, A
rH) Liquid crystallinity The following structural formula obtained in [C] above 4,7-di (4-methoxyphenyl) -1,2,5 represented by
The thermal phase change (DSC measurement) of thiadiazolo [3,4-c] pyridine ( 5a ) was as follows. In addition,
() Indicates ΔH (kcal / mol).

Example 3 Synthesis method [A] Ethyl-4,7-di (4-butoxyphenyl)-
1,2,5-thiadiazolo [3,4-c] pyridine-6-carboxylate ( 2c ) and butyl-4,7-di (4-butoxyphenyl) -1,2,5-thiadiazolo [3,4- c] Synthesis of pyridine-6-carboxylate ( 3c ).

3,4-Di (4-butoxybenzoyl) -1,2,5-thiadiazole ( 1c ) (0.3g, 0.7mmol) and glycine ethyl ester hydrochloride (0.3g, 2.1mmol) in butanol (30ml)
After heating for 72 hours, the same treatment as in [A] of Example 1 was carried out to obtain ethyl-4,7-di (4-butoxyphenyl) -1,2,5-thiadiazolo [3,4-c] pyridine-6. -Carboxylate ( 2c ) and butyl-4,7-di (4-butoxyphenyl)-
A mixture (0.33 g) with 1,2,5-thiadiazolo [3,4-c] pyridine-6-carboxylate ( 3c ) was obtained.

[B] 4,7-di (4-butoxyphenyl) -1,2,5-thiadiazolo [3,4-c] pyridine-6-carboxylic acid ( 4
c ) Synthesis.

A mixture of ( 2c ) and ( 3c ) synthesized in the above [A] (0.
33 g) is not separated, and as it is in Example 1 [B].
4,7-di (4-butoxyphenyl) -1,2,5-thiadiazolo [3,4-c] pyridine-6
-Carboxylic acid ( 4c ) (0.27g) (orange powder) was obtained. The melting point of this product was 150 ° C.

[C] Synthesis of 4,7-di (4-butoxyphenyl) -1,2,5-thiadiazolo [3,4-c] pyridine ( 5c ).

The ( 4c ) (0.27 g, 0.57 mmol) obtained in the above [B] was used as it was without recrystallization and treated in the same manner as in the [C] of Example 1 to obtain 4,7-di (4-butoxy). Phenyl) -1,
2,5-thiadiazolo [3,4-c] pyridine ( 5c ) (0.02g,
0.05 mmol, yield 9%) was obtained. Unreacted ( 4c ) was recovered (40%).

Physical properties ( 5c ) Melting point: 116 ° C Orange prism crystal (recrystallized from ethanol) Mass spectrum: m / e 433 (M +) ¹ H-NMR spectrum (CDCl ₃ ): δ 1.00 (6H, t, CH ₃ ). , 1.50 (8H, m, CH ₂ ), 4.04 (2H, t, OC
H ₂ ), 4.06 (2H, t, OCH ₂ ), 7.04 (4H, m, ArH), 7.90 (2H,
m, ArH), 8.60 (2H, m, ArH), 8.68 (1H, s, ArH) Liquid crystallinity The following structural formula obtained in [C] above 4,7-di (4-butoxyphenyl) -1,2,5
-The state of thermal phase change of thiadiazolo [3,4-c] pyridine ( 5c ) (DSC measurement) was as follows. In addition,
() Indicates ΔH (kcal / mol).

Example 4 According to the method described in Examples 1 to 3, in the general formula [I], Z is CH, and R ¹ and R ² are diarylthiadiazoloheterocyclic compounds shown in Table 1. Liquid crystal compounds No. 1 to 16 were synthesized. All of them showed good liquid crystallinity.

Example 5 Synthesis method [A] Synthesis of 4,7-di (4-butoxyphenyl) -1,2,5-thiadiazolo [3,4-d] pyridazine ( 5d ).

15 ml of an acetic acid solution containing 0.3 g of 3,4-di (4-butoxybenzoyl) -1,2,5-thiadiazole ( 1c ) and 0.1 g of hydrazine hydrate was refluxed for 24 hours. After cooling, the precipitated crystals were collected by filtration, washed with ethanol, and 4,7-di (4-butoxyphenyl) -1,2,5-thiadiazolo [3,4-d] pyridazine ( 5d ) (0.23 g ) Got.

Liquid crystallinity The following structural formula obtained in [A] above 4,7-di (4-butoxyphenyl) -1,2,5
-The state of thermal phase change (DSC measurement) of thiadiazolo [3,4-d] pyridazine (5b) was as follows.

Example 6 According to the method described in Example 5, the above general formula [I]
, Z is N, and R ¹ and R ² are liquid crystal compounds No. 1 consisting of diaryl thiadiazoloheterocyclic compounds shown in Table 2.
7-28 were synthesized. All of them showed good liquid crystallinity.

[Effect of the Invention] As described in detail above, according to the liquid crystal material of the present invention, a novel high-performance liquid crystal material comprising a specific diaryl thiadiazolo heterocyclic compound is provided.

Therefore, according to the liquid crystal material of the present invention, the substance providing the liquid crystal material and the field of application of the liquid crystal technology can be expanded, and its industrial utility is extremely high.

Claims (1)

(57) [Claims] 1. A compound of the general formula [I] (In the formula, Z represents CH or N, R ¹ and R ² are alkyl groups,
It represents a cycloalkyl group, a bicycloalkyl group, a cycloalkyloxy group, an alkoxy group or an alkylcarbonyloxy group. ) A liquid crystal material comprising a diaryl thiadiazolo heterocyclic compound represented by: