JPH02180869A - Optically active compound and use thereof - Google Patents

Abstract

NEW MATERIAL:An optically active compound of formula I [at least one of the rings a and b is a polyhalogeno ring containing totally four F atoms or F and Cl atoms or the remaining rings are (halogen-substituted) benzene rings; L is -COO- or -OCO-; Q is -O- or direct bond; R is >=4C alkyl wherein at least one of R and a group of formula II is an optically active group]. EXAMPLE:6-Decyloxypyridine-3-carboxylic acid 4'-[3-fluoro-4-(perfluoro-1- propyloxyethylcarbonyl)phenyloxycarboxyl]tetrafluorophenyl ester. USE:One component for liquid crystal compositions. The compound of formula I is used for materials or optically switching elements capable of responding at high speeds and exhibiting chiral smectic phases over a wide temperature range. PREPARATION:A compound of formula VI and a compound of formula XI separately prepared through several intermediates, respectively, are reacted with each other to provide the compound of formula I wherein L is -COO-.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention relates to a novel optically active compound, a liquid crystal composition containing the compound, and a liquid crystal composition containing the compound or at least one of the compounds as a component. The present invention relates to an optical switching element constructed using the present invention.

[Conventional technology]

Currently, the display systems of liquid crystal display elements that are widely used in practical use are twisted nematic (TN) and dynamic scattering (DB). These are displays using nematic liquid crystal cells that mainly contain nematic liquid crystals, but one of the disadvantages of conventional nematic liquid crystal cells is the fact that the response speed is slow, and the response speed can only be on the order of a few milliseconds at most. can give. This is one of the factors that limits the range of applications of nematic liquid crystal cells. In contrast, it has recently become clear that a faster response can be obtained by using a smectic liquid crystal cell.

It is known that some optically active smectic liquid crystals exhibit ferroelectricity, and there is great interest in their applications. Ferroelectric liquid crystal was developed in 1975 by R.
, B., Mayer (R.B.

Meyer) G) (Journard de Fuisique ('J, Phya, ), Vol. 36, No. L69 (
1975)), it was first synthesized by 4-
(4-n-decyloxybenzylideneamino) -27
It is a V-rough base-based compound whose representative example is (DOBAMBO), which is characterized by exhibiting ferroelectricity in an optically active state, for example, in the Kaiflusmectic 0 phase. be. After that, N
, Enter Clark (N, A.

C1arlc) et al. [Abphytophysics Letters (Appx, phys, Lett, ) Vol. 36, p. 899 (t9so)) K. discovered high-speed response on the microsecond order in DOBAMBO thin film-tcA/Vc. This led to the development of ferroelectric liquid crystals, which are used not only for displays such as liquid crystal televisions, but also for optoelectronic devices such as optical printer heads, optical Fourier transform elements, and light valves, by taking advantage of their high-speed response and memory properties. It is attracting attention as a material that can also be used for related device parts. In ferroelectric liquid crystal cells, the use of a material with a high dielectric constant (and a large spontaneous polarization) is advantageous because the cell can be driven at high speed, so the development of a material with a large spontaneous polarization is desired.

In addition, for practical purposes, it is necessary that the liquid crystal compound or composition itself be stable and exhibit ferroelectricity over a wide temperature range centered around room temperature.

[Problem to be solved by the invention]

However, V rough base type compounds such as DOBAMBO have drawbacks in terms of stability against water and light, and the temperature range in which they exhibit ferroelectricity is 9,400 degrees higher than room temperature, making them unsuitable for practical use. There wasn't. Therefore, there are strong expectations for the realization of a material system that is physically and chemically stable and has large spontaneous polarization as a ferroelectric liquid crystal material.

An object of the present invention is to obtain a novel optically active compound that has excellent chemical stability and photostability, has large spontaneous polarization, and has a wide temperature range of chiral smectic C phase. The present invention also aims to provide display elements and the like having high-speed response using such optically active compounds or liquid crystal compositions.

[Means to solve the problem]

To summarize the present invention, the first invention of the present invention relates to an optically active compound, which includes the following: [However, at least one of rings a and b has a total of 4 fluorine atoms, or It is a polyhalogen ring containing fluorine and chlorine, and the others are benzene rings that may be substituted with halogen, L is -COO- group or -OC〇- group, Q is 10-group or direct bond, R is an alkyl group having 4 or more carbon atoms, and at least one of the group R or the C8-7001F (OF3) group is an optically active group.

Moreover, the second invention of the present invention relates to a liquid crystal composition, and is characterized in that it contains at least one kind of the optically active compound of the first invention as a component.

A third invention of the present invention relates to an optical switching element, which is constructed using a liquid crystal composition containing the optically active compound of the first invention or a small amount (at least one kind) of this compound. It is characterized by being

The compound of -Fukudai (1) has a central skeleton having a benzoic acid phenyl ester structure, and further has long chain substituents (preferably 4 to 18 carbon atoms) at both ends of the molecule. It itself exhibits liquid crystallinity. In addition, this compound has a strong μbonyl group and an OF3 group directly bonded to the asymmetric carbon, and the dipole moment of the pyridine ring, fluorine, or chlorine acts transversely to the long axis of the molecule, resulting in high optical rotation. It has a sexual nature. In addition, since the presence of multiple fluorines causes a decrease in surface energy, it is expected that the resistance to domain rotation will be reduced compared to non-fluorine compounds in the thin cells essential for ferroelectric liquid crystals. When these factors are combined, high-speed response can be expected when used as a display element.

[Production method of compound]

The optically active compound of general formula (1) in the present invention can be produced, for example, according to the following synthetic route.

However, in the following reaction formula, Q or Q may represent an unsubstituted benzene ring.

(Xri(OFρoc, ya(1,L=-oco-1Q,=-0-)(OFρOO,
H7 (1,L=-000-) To outline the above production process, 6-chloronicotinic acid and sodium alkoxide are first reacted to produce 6-alkyloxynicotinic acid <u). Next, this was converted into acid chloride (III), and then reacted with a 4-hydroxybenzoic acid compound (■) in the presence of a salty substance to produce acid chloride (V), which was then converted into acid chloride (CVI'). shall be.

Further, a phenol compound (■) is produced by esterifying the hydroponic acid (II) and a dihydroxy compound (■) in the presence of an acid catalyst.

On the other hand, the dihydroxy compound is esterified with perfluoro-2-propyloxypropionic acid (K), or the hydroxy compound is acylated with acid chloride (X) K to form perfluoro-1-propyloxyethyl carbon diy A phenol compound (XI) into which a group has been introduced is produced.

Furthermore, 4-hydroxybenzoic acid compound (Xll) is reacted with acid clophyte (X) to produce a benzoic acid compound (Xlll) into which a perfluoro-1-propyloxyethylcarbonyloxy group has been introduced, and this is Using a chlorinating agent such as thionyl chloride, it is converted to silicyl chloride (XF/).

Finally, acid chloride (M) and phenolic compound (XI
) or phenolic compounds (■) and acid q-phyto (
XF/) in the presence of a basic substance to form the general formula (I
) is produced by producing the compound shown in

In the above manufacturing process, the target compound is usually manufactured using optically active perfluoro-2-propyloxypropionic acid, but when using a compound in which R is an optically active group, racemic acid is used. The target compound can be produced in the same manner using this method.

In addition, in the compound (F/) or (x5), a 4-hydroxybenzoic acid compound containing four fluorine or fluorine and chlorine is described in Document 1: Partial (, T, M, Bi
rchall) and others, Jhana A/e Op Chemica/L'-Society (, r, Chem, 8oc,
), 1971, p. 1345 or document 2: Akio Takaoka, Yoroki Ishikawa et al., Journal of the Chemical Society of Japan, 1985, No. 21
It can be produced from polyfluorobenzonitrile according to page 55.

In addition, compounds containing one fluorine are described in Reference 3: Sadao Takehara et al., Proceedings of the 11th Liquid Crystal Symposium, 1985, No. 176.
It can be manufactured from fluoroanisole according to the method on page 1.

〔Example〕

Hereinafter, the present invention will be explained in more detail with reference to Examples.
The scope of application of the present invention is not limited by these examples.

).

Example 1 (&) Metallic sodium in a nitrogen atmosphere 2. After heating and dissolving 1-decanol/1/12.6F and toluene at 20°C, toluene was distilled off under reduced pressure, and a solution of 140d of N-methylpyrrolidone containing 6-chloronicotinic acid 13P was added to 150°C. The mixture was heated and reacted at 5° C. for 17 hours. Add cooled water, neutralize with dilute hydrochloric acid and dilute acetic acid to make it neutral, extract toluene, wash with water, dry over anhydrous magnesium sulfate, pass the toluene solution through a silica gel column, and distill off the solvent. 6-zosyloxynicotinic acid (II, u=c
,. Ext) was obtained.

(b) After heating and reacting 1.4 t of the above carboxylic acid compound with thioni chloride A/15d for 5 hours, the thioni chloride was distilled off to obtain a toene solution of 1 t-4-hydroxyteF Benzoic acid 1. O2 pyridine 30m
The mixture was gradually added to the solution of -
After standing overnight, it was poured into water and extracted with toluene. The toluene solution was washed with water, dried over anhydrous magnesium sulfate, and the solvent was distilled off through a silica gel column.
Recrystallize with μ to obtain 6-zosoxynicotinic acid-4'-
Carboquine Tetofuolophenylester A/(■,
R""lOH2! , ring a: w-z-='ytp
) was obtained.

(c) Dissolve m-7/v olofeno-A/2.8 f in 80 carbon disulfide, add 7 t of ground anhydrous aluminum chloride, and stir to form the optically active half-olof 2-propyloxyderopion. acid lofito a7f/
Carbon disulfide 50m7! The solution was added dropwise at 7°C or below, then heated under reflux for 5 hours, poured into dilute hydrochloric acid after cooling, extracted with ether, washed with water, dried over anhydrous magnesium sulfate, the solvent was distilled off, and the residue was The solution was dissolved in a hexane-toluene mixed solvent and passed through a silica gel column, and the solvent was distilled off. (X1
1 Ring b: sy, Q = direct bond, however, the substitution position of the halogen atom was according to the definition in Table 1, notes) was produced.

Acid compound (V) produced in ((1) ff1) 1.
Compound (XI) produced with 2 F and (c) t 1t
Compound ■: 6-decyloxypyridine-5-hydroponic acid-
4'-(5-)p-4-(perfluoro-1-propyloxyethylcarbony/I/)phenyloxyca~
Boni]tetoffluorophene ester was produced.

When this compound was sealed in a glass cell with a transparent EELL gap of approximately 3 μm and observed under a polarizing microscope while applying an electric field of ±5 V, I Tlz, it was found that the domain reversed as the electric field reversed from 53°C as the temperature decreased. was recognized. Other phase transition temperatures are shown in Table 1. Note that Ory is a crystalline state, and SC* is a ferroelectric chiral smectic C phase, which is a phase that at least partially responds to the above electric field. 8A indicates a smectic physiognomy, Ch 2 indicates a cholesteric phase, and I indicates an isotropic liquid phase.

Also, / indicates that the phase exists.

Note that () indicates that the phase is monotropic.

This compound was sealed in a cell with an electrode gap of 115 μm, and the triangular wave method reported by Miyazato et al.
e, IPukuda) and others, Japanese
Journal of Applied Physics (Jpn.

J, AppL Phys, 1985, Volume 22, Page L661], the spontaneous polarization was measured and the value was 230 no/elII''.

Example 2 1-octatool was substituted for 1-decanol, and 4-hydroxy- was substituted for 4-hydroxytetrafluorobenzoic acid.
Compound (1): 6-octyloxypyridine-3-carboxylic acid-4'-C5-fluoro-4-(perfluoro-1-propyloxy Ethyl carbonyl A/)
Phenyloxycarbonyl)-3/-chlorotrifluorophenyl ester was prepared. The phase transition temperature of this compound is as shown in Table 1.

In addition, the value of spontaneous polarization measured in the same manner as in Example 1 was 17
0n07cm”.

Example 3 Compound ■: 6 was prepared in the same manner as in Example 1 except that m-fluoropheno-# was replaced by i-teo-ri-a-phenol.
-decyloxypyridine-3-carboxylic acid-4'-[2
-Chloro-4-(perfluoro-1-propyρoxyethylρcarbonylv)phenyloxycarbonylcotetrafluorophenyl ester was produced. The phase transition temperature of this compound is shown in Table 1.

Example 4 Optically active perfluoro-2-propyloxypropionic acid 50? , fluorohydroquinone 1.2f and p-)/
1.12 l/enesulfonic acid was heated to reflux with 150 d of toene, and the reaction was carried out for 30 hours while removing the produced water from the system. After cooling, the mixture was washed with a dilute aqueous sodium hydroxide solution and then with water, and then with anhydrous magnesium sulfate. After drying and passing through a silica gel column, the solvent was distilled off and recrystallized from benzene to obtain 3-fluoro-4-(berfluoro-1-propyloxyethylcarbonyloxy)phenol (XI,
Ring b: 3-IF%q=-〇- group) was produced.

Compound (V) produced in the above compound and Example 1(b)
Esterification was carried out in the same manner as in Example 1(b) using )
Preparation of μO-4-(perfluoro-1-propyloxyethylcarbonyloxy)phe-ruoxycarbony]tetrafluorophenyl ester.

The phase transition temperature of this compound is as shown in Table 1. However, - indicates that the existence of that phase is not clear.

Example 5 Compound (XI) was prepared in the same manner as in Example 4 using hydroquinone instead of fluorohydroquinone.

Ring b: unsubstituted, Q, =-0- group) was produced. Also 1
The compound (vlR=C,
Hl, ring a: W-Z=F) was produced.

Example 1(b) using compound (XI) and compound (V)
), and then treated in the same manner as in Example 1(d) to form compound (1): 6-hexyloxypyridine-3-carboxylic acid-a'-(a-(barfluor a-1-
Propyloxyethylcarbonyloxy)phenyloxycarbonyl]tetoffluorophenyl ester was produced. The phase transition temperature of this compound is shown in Table 1.

Example 6 The transition temperatures are shown in Table 1.

Example 7 Compounds (■,
R=01°■, ring a=unsubstituted) was produced. In addition, acid chloride (X) and 4-hydroxy-3-chlorotrifluorobenzoic acid were heated to react in a benzene solvent in the presence of triethylamine for 5 hours, and Example 1 (
Treated in the same manner as in b), compound < xm, ring b: v=x=
z=F%! =04) was manufactured.

Esterification was carried out in the same manner as above using compounds (■) and (■), and then treated in the same manner as in Example 1(d) to obtain compound (■): 6-decy-oxypyridine-3-carboxylic acid-4.
'-(4-(Perfluoro-1-propyloxyethylcarbonyloxy)-3-chlorotrifluorobenzoyloxy]phenylene ester was prepared. The phase of this compound was prepared using 1-octatool in place of 1-decanol. Example 1 Compounds produced in the same manner as (a) (■, R''
(sTixt) and chlorohydroquinone to prepare the compound (■, ring a: 5-at
) was manufactured.

Further, acid compound 0Qll) was produced in the same manner as in Example 6 using acid clophyte (X) and 4-hydroxytetrafluorobenzoic acid.

Esterification was carried out in the same manner as in Example 1(b) using compounds (■) and (■), and then treated in the same manner as in Example 1(d) to obtain the compound =6-octyloxypyridine-3-carvone. Acid-3'-chloro-4'-(4-(berfluoro-1-propyloxyethylcarbonyloxy)tetoffluorobenzoyloxy)phenyl ester was prepared. The phase transition temperature of this compound is shown in Table 1. .

Example 8 Example? Optically active 2-octano-7M instead of 1-decanol
, 4-instead of 4-hydroxytetrafluorobenzoic acid
Hydroxy-3-chlorotriftvorobenzoic acid, m-
Compound 1 was prepared in the same manner as in Example 1 using phenol instead of fluorophenol and its racemate instead of optically active perfluoro-2-propyloxypropionic acid.
:6-(1-methylhebutyloxy)pyridine-3-carboxylic acid-4'-(4-(barfluora-1-propylene)
(oxyethylcarbonyl) phenyloxycarbonyl)
-21-Chlorotrifluorophenyl ester was produced. The phase transition temperature of this compound is shown in Table 1.

A compound (■, R=C!1°H21, ring a: W
-Z=IF) was produced.

Also, acid chloride (X) and 4-hydroxy-5-7
Example 1
The compound (X1ll, ring b: 5
-F') was produced.

Using these compounds (■) and (Xllll), an esterification reaction was carried out in the same manner as above, and then Example 1(d)
Compound (1): 6-decyloxypyridine-3-caponem-4'-C5-fluoro-4-(perfluoro-1-propyloxyethylcarbonyloxy)benzoyloxycotetrafluorophenyl ester was manufactured. The phase transition temperature of this compound is as shown in Table 1.

Example 10 Syloxypyridine-3-power, rubonic acid-4'-[:
4-(Perfluoro-1-propyloxyethylcarbonyloxy) tetrafluoroinzoyok! /''l tetrafluorophenyl ester was produced. The phase transition temperature of this compound is shown in Table 1.

Compounds (■, R=C, H8, ring a: W-Z=IF) was produced. Also, acid crophyte (
x) and 4-hydroxytetrafluorobenzoic acid, the compound (xm, ring b: W~z
=y) was produced.

Using these compounds (■) and (xm), an esterification reaction was carried out in the same manner as above, and then Example 1 (d
) to form a compound @=6-hex Example 11 (Liquid crystal composition) 4-( of the following structural formula, which is a nonkylar smectic liquid crystal)
2-methylbutyl)-al-biphenylcarboxylic acid-42-octyloxyphenyl ester 25 parts by weight,
and 4-octyloxy-4'-biphenylcarboxylic acid-4'-pentyloxyphenylester yv 45 weight ik were mixed together to prepare a liquid crystal composition.

(Liquid crystal composition) 4-(2-methylbuty#)-4'-biphenylcarboxylic acid-41-octyloxyphenyl ester 70, which is a non-kaiflu smectic liquid crystal, was added to 20 parts by weight of compound (1) in Example 3. Parts by weight, and 4-octyloxybenzoic acid-4'-(2-methylbutyloxy)phenyl ester of the following structural formula/' 10 heavy J[i
A liquid crystal composition was prepared by mixing S'.

This liquid crystal composition exhibited an sc* phase in the range of 1°C to 62°C, and its temperature range was significantly expanded compared to that of a single compound.

Example 12 This liquid crystal composition exhibits an sc main phase in the range of 8 to 55°C,
The temperature range was significantly expanded compared to the case of Compound ① alone.

Example 13 (Liquid crystal composition) 1 of each of the compounds and ■ in Examples 7 and 10
Liquid crystal compositions were prepared by mixing 45 and 30 parts by weight of the non-transparent smectic liquid crystal in Example 11 with 5 and 10 parts by weight, respectively. This liquid crystal composition has 4
They exhibited an SC umbrella phase in the range of ~60°C, and the temperature range was significantly expanded compared to the case of each compound alone.

As shown in the three examples above, by mixing liquid crystal compounds with different structures, it is possible to obtain a liquid crystal composition that forms a chiral smectic C liquid crystal over a wider temperature range than when used alone, and moreover, above and below room temperature. .

Example 14 (Optical switching element) Compound (1) obtained in Example 1 was heated in a glass cell in which a polyimide film was subjected to a rubbing alignment treatment and the gap between transparent electrodes was maintained at approximately 3 μm with alumina powder to make it isotropic. It became a liquid and had a halo. This cell was slowly cooled and maintained at 50°C, and when a square wave of ±2QV, 10) 1g was applied, the change in transmitted light intensity was measured using a photomultiplier tube.
Response time for 0 to 904 changes in light intensity is 75 μsec
, and showed high-speed responsiveness.

Example 15 (Optical switching element) A cell was produced in the same manner as in Example 14 using the liquid crystal compositions prepared in Examples 11 to 13. The measured temperature is 33
The response times determined under the same conditions as in Example 14 except that the temperature was 155.70 and 45μ813Q, respectively, showed high-speed response.

〔Effect of the invention〕

As explained above, according to the present invention, by using an optically active compound represented by 1 or a liquid crystal composition containing at least one of these optically active compounds as a component, the spontaneous polarization is large. When used as a display element, it is possible to provide not only a high-speed response but also a material system and an optical switching element that exhibits a chiflusmectic phase over a wide temperature range.

Claims (1)

[Claims] 1. The following general formula I: ▲There are mathematical formulas, chemical formulas, tables, etc.▼...(I) [However, at least one of rings a and b has a total of four fluorine atoms, or fluorine and a polyhalogen ring containing chlorine, the others are benzene rings which may be substituted with halogen, L is -COO- group or -OCO- group, and Q is -
O- group or direct bond, R is an alkyl group having 4 or more carbon atoms, and at least one of the group R or the C_3F_7OCF (CF_3) group is an optically active group. . 2. A liquid crystal composition containing at least one optically active compound according to claim 1 as a component. 3. An optical switching element constructed using the optically active compound according to claim 1 or a liquid crystal composition containing at least one of the compounds as a component.