JPH07278308A - Cyclic silicone derivative and its production - Google Patents

Abstract

PURPOSE:To obtain the subject new compound having a polycyclic hydrocarbon group-containing siloxane structure, exhibiting liquid crystal property in wide temperature range, excellent in thermal stability and useful for display devices, etc. CONSTITUTION:This compound is expressed by formula I [R<1>, R<2> and R<3> each is methyl or phenyl; R<4> is a 7-30C polycyclic hydrocarbon group such as (dihydro)cholesterol residue; A is a bifunctional group consisting of C, H and O, e.g. a group of the formula (CH2) [(b) is 2-10; (m) and (n) each is 1-15 or 0-15; (m)+(n)>=3], e.g. a compound of formula II. The compound of formula I is obtained by reacting a compound of formula III [X is a bifunctional group corresponding to A, e.g. a group of the formula (CH2)b-2COO] in the presence of a hydrosilylated catalyst such as platinic chloride.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a novel cyclic silicone derivative having excellent properties as a liquid crystal material and a method for producing the same.

[0002]

2. Description of the Related Art Since liquid crystals have an optical modulation effect due to the application of an electric field, they are mainly applied in the field of electronics such as display devices and have a high added value. It has attracted attention as a functional material. Among them, steroid compounds centering on cholesterol are known to exhibit cholesteric liquid crystals, and are characterized by having high thermal stability.

However, there is a problem that the temperature range in which liquid crystals of these steroid compounds are exhibited is narrow and the applicable range is limited. On the other hand, it is also known that the liquid crystal region is expanded by binding a steroid compound to the polymer chain and binding the mesogen, and the liquid crystal region is shifted to the low temperature side by using a flexible silicone as the main chain. . However, because of the high molecular weight, the mobility of the molecules is reduced, and the response speed to an electrical change is slowed, so that there is a problem that it is difficult to apply as a display element.

Therefore, it exhibits liquid crystallinity in a wide temperature range,
Moreover, development of a thermally stable low-molecular liquid crystal material has been desired.

[0005]

Under the circumstances, the inventors of the present invention have conducted extensive studies, and as a result, have found that a novel silicone derivative obtained by introducing a polycyclic hydrocarbon group such as a steroid into a small cyclic silicone is obtained. The inventors have found that the low-molecular weight compound exhibits liquid crystallinity in a wide temperature range and is thermally stable, and completed the present invention.

That is, the present invention provides the following general formula (1)

[0007]

[Chemical 4]

(In the formula, R ¹ , R ² and R ³ may be the same or different and each represents a methyl group or a phenyl group, R ⁴
Is a polycyclic hydrocarbon group having 7 to 30 carbon atoms, A is a carbon atom,
A divalent group consisting of a hydrogen atom and an oxygen atom, n is 0 to 15
, M is an integer of 1 to 15, and n + m ≧ 3. ) Related to a cyclic silicone derivative and a method for producing the same.

In the general formula (1), the polycyclic hydrocarbon group having 7 to 30 carbon atoms represented by R ⁴ includes terpenoid compounds such as pinane and bornane, steroid compounds such as cholesterol, and polynuclear compounds such as naphthalene and anthracene. Examples include residues such as aromatic compounds. Among them, a steroid residue is preferable because it exhibits stable liquid crystallinity, and a residue obtained by removing a hydroxyl group from cholesterol, dihydrocholesterol or citrosterol showing a particularly wide liquid crystal region is particularly preferable.

In the general formula (1), the divalent group consisting of a carbon atom, a hydrogen atom and an oxygen atom represented by A is not particularly limited. For example,-(CH ₂ ) _a -O- (a is 2 ~ 1
_{1), - (CH 2)} b -COO- (b is _{2~10), - (CH 2)} c -OCOO- (c
Is _{2~11), - (CH 2)} d -O- (CH 2) e -O- (d is 3 to 11, e is _{2~12), - (CH 2)} f -OCH 2 COO- (f Is 3 to 11),-(CH ₂ ) _g-
OC ₆ H ₄ -COO- (g is 3 to 11), -CH ₂ CH ₂ CH ₂ OCH ₂ CH (OH) CH ₂
0-, -CH ₂ CH ₂ -C ₆ H ₄ -COO-, -CH ₂ CH ₂ CH ₂ O- (CH ₂ CH ₂ O) _h -COO-
(H is 1 to 20) and the like, among which — (CH ₂ ) _b —COO— is preferable.

In the general formula (1), n is an integer of 0 to 15 and m is an integer of 1 to 15. In order to have a wide liquid crystal region, n is 0 to 6 and m is 1 to 7. , And n is 0 to 2, m
Is preferably 3-5. Those in which n is 0 and m is 4 are more stable and exhibit liquid crystallinity in a wide temperature range.
Also, the sum of n and m must be 3 or more,
The range of 3 to 7 is preferable in order to secure the stability and fluidity of molecules suitable as a liquid crystal for a display device.

The cyclic silicone derivative (1) of the present invention is produced, for example, according to the following reaction formula.

[0013]

[Chemical 5]

(In the formula, R ^{1 to} R ⁴ , A, n and m have the same meanings as described above, X is a divalent group consisting of a carbon atom, a hydrogen atom and an oxygen atom, and has a carbon number from A). 2 shows less.)

That is, an olefin (3) having a polycyclic hydrocarbon group and a hydrogencyclosiloxane (2) are
The cyclic silicone derivative (1) is produced by reacting in the presence of a hydrosilylation catalyst.

This reaction is carried out at room temperature or 60 to 80 in a suitable solvent.
It is preferably carried out under heating conditions of ° C.

The hydrogencyclosiloxane (2) used in the production of the cyclic silicone derivative (1) of the present invention is
For example, dichloromethylsilane and / or dichlorophenylsilane, or those obtained by hydrolyzing these with dichlorodimethylsilane, dichlorodiphenylsilane and / or dichloromethylphenylsilane, specifically, trimethylcyclotrisiloxane, tetra Methylcyclotetrasiloxane, pentamethylcyclopentasiloxane, hexamethylcyclohexasiloxane, heptamethylcycloheptasiloxane, hexamethylcyclotetrasiloxane, hexamethylcyclopentasiloxane, tetraphenylcyclotetrasiloxane,
Examples include pentaphenylcyclopentasiloxane, dimethyldiphenylcyclotetrasiloxane, dimethyltriphenylcyclopentasiloxane. These may be used alone or in combination of two or more.

Olefin having a polycyclic hydrocarbon group (3)
Is, for example, as X corresponding to the above A,-(CH ₂ ) _{a-2-
O -, - (CH 2)} b-2 -COO -, - (CH 2) c-2 -OCOO -, - (CH 2) d-2 -O-
(CH ₂ ) eO-,-(CH ₂ ) _f-2 -OCH ₂ COO-,-(CH ₂ ) _g-2 -OC ₆ H ₄ -CO
_{O -, - CH 2 OCH 2} CH (OH) CH 2 0 -, - C6H 4 -COO -, - CH 2 O- (CH 2 CH 2
O) _h —COO— and the like (a to _h have the same meanings as described above), and R ⁴ is a polycyclic hydrocarbon group having 7 to 30 carbon atoms, for example, terpenoid compounds such as pinane and bornane, and cholesterol. And the like, and those having a residue such as polynuclear aromatic compounds such as naphthalene and anthracene. Among these, those in which X is-(CH ₂ ) _b-2 -COO- and R ⁴ is a residue of a steroid compound, particularly a residue of cholesterol, dihydrocholesterol or citrosterol are preferable. The amount of the olefin (3) used is preferably 1.0 to 3.0 equivalents relative to the Si-H of the hydrogencyclosiloxane (2).

As the hydrosilylation catalyst, any conventionally known one can be used. For example, typical chloroplatinic acid and US Pat. Nos. 3159601 and 3159662,
Platinum-containing catalysts as described in the respective specifications of Nos. 3220970, 3516946, and 3814730, and others based on rhodium, ruthenium, palladium, osmium, iridium, or platinum are used. . The amount of the hydrosilylation catalyst used is preferably 20 × 10 ^{−6 to} 300 × 10 ⁻⁶ mol times the Si—H unit of the hydrogencyclosiloxane (2).

As the reaction solvent, for example, those which do not influence the reaction such as toluene and hexane are used.

[0021]

FUNCTION AND EFFECT OF THE INVENTION Cyclic silicone derivative of the present invention
(1) exhibits liquid crystallinity in a wide temperature range, which was not observed in polycyclic hydrocarbon compounds such as steroids. Although the reason for this is not clear, the mesogen is bound to the polycyclic hydrocarbon group to be strongly bound, and the cyclic main chain has a flexible cyclosiloxane skeleton, so that the mesogen has a conformation in which it easily interacts with each other. Therefore, it is considered that it exhibits liquid crystallinity in a wide temperature range.

As described above, the cyclic silicone derivative (1) of the present invention is a low molecular weight compound having liquid crystallinity in a wide temperature range and high thermal stability, and is excellent as a liquid crystal for a display device such as a display device. It has the property.

[0023]

The present invention will be described in more detail with reference to examples, but the present invention is not limited thereto.

Example 1 Synthesis of Cholesteryl Butanoate Modified Cyclic Silicone:

[0025]

[Chemical 6]

In a 300 ml flask equipped with a Dean-Stark trap, 116 g of cholesterol (0.3 mol), 3-butenoic acid
28 g (0.33 mol), p-toluenesulfonic acid 0.52 g (0.00
(3 mol) and 150 ml of toluene were charged, and under reflux of toluene,
The reaction was carried out for 5 hours while dehydrating. The reaction mixture was washed twice with 5% aqueous sodium hydrogen carbonate solution and then twice with water. After the solvent was distilled off under reduced pressure, the residue was recrystallized from ethanol to give cholesteryl 3-butenoate 66.
g was obtained. The ¹ H-NMR and IR spectra of this product are shown in FIG.
And 2 were shown. Next, 33 g (0.073 mol) of the obtained cholesterol 3-butenoate, 4 g (0.017 mol) of tetramethylcyclotetrasiloxane and 50 m of toluene
l and 0.38 g of a 1% toluene-1-hexanol mixed solution of chloroplatinic acid (10: 1) were charged to a 200 ml flask, and 60
The reaction was carried out at 0 ° C for 2 hours. 1 g of activated carbon and 50 ml of ethanol were added to the reaction mixture, and the mixture was further stirred at 60 ° C. for 2 hours, and the activated carbon was removed by suction filtration. After distilling off the solvent under reduced pressure,
35 g of the target compound was obtained. The ¹ H-NMR and IR spectra of this product are as shown in FIGS. 3 and 4, which revealed that it had the title structure. The obtained cholesteryl butanoate-modified cyclic silicone showed dislocation points at 36.8 ° C and 148.7 ° C by differential scanning calorimetry, and a fan-shaped structure characteristic of liquid crystal was observed by a polarization microscope in the temperature range between these two points. It was found to exhibit liquid crystals.

Example 2 Synthesis of Cholesteryl Undecanoate Modified Cyclic Silicone:

[0028]

[Chemical 7]

The target compound was obtained in the same manner as in Example 1 except that 10-undecenoic acid was used instead of 3-butenoic acid.
The ¹ H-NMR and IR spectra of the product were as shown in FIGS. 5 and 6. The obtained cholesteryl undecanoate-modified cyclic silicone had a differential scanning calorimetry value of 9.8 ° C and 131.5 ° C.
A dislocation point was shown at ° C, and in the temperature range between these two points, a fan-shaped structure characteristic of the liquid crystal was observed by a polarization microscope observation, and it was found that the liquid crystal was shown.

[Brief description of drawings]

FIG. 1 is a chart showing 1H-NMR spectrum of cholesteryl 3-butenoate.

FIG. 2 is a diagram showing an IR spectrum of cholesteryl 3-butenoate.

FIG. 3 is a diagram showing a 1 H-NMR spectrum of a cholesteryl butanoate-modified cyclic silicone which is a compound of the present invention.

FIG. 4 is a diagram showing a spectrum of a cholesteryl butanoate-modified cyclic silicone which is a compound of the present invention.

FIG. 5 is a chart showing 1H-NMR spectrum of cholesteryl undecanoate-modified cyclic silicone which is a compound of the present invention.

FIG. 6 is a diagram showing a spectrum of a cholesteryl undecanoate-modified cyclic silicone that is a compound of the present invention.

Claims (8)

[Claims] 1. The following general formula (1): (In the formula, R ¹ , R ² and R ³ may be the same or different,
Each is a methyl group or a phenyl group, and R ⁴ has 7 to ³ carbon atoms.
0 is a polycyclic hydrocarbon group, A is a divalent group consisting of a carbon atom, a hydrogen atom and an oxygen atom, n is an integer of 0 to 15, m is
Represents an integer of 1 to 15 and n + m ≧ 3. ) A cyclic silicone derivative represented by: 2. The cyclic silicone derivative according to claim 1, wherein R ⁴ is a steroid residue. 3. The cyclic silicone derivative according to claim 2, wherein the steroid residue is a monovalent group obtained by removing a hydroxyl group from cholesterol, dihydrocholesterol or citrosterol. 4. The cyclic silicone derivative according to claim 1, wherein n is 0 to 2. 5. The cyclic silicone derivative according to claim 1, wherein n is 0. 6. The cyclic silicone derivative according to claim 1, wherein m is 3-5. 7. The cyclic silicone derivative according to claim 1, wherein m is 4. 8. The following general formula (3): (In the formula, R ⁴ is a polycyclic hydrocarbon group having 7 to 30 carbon atoms,
Represents a divalent group consisting of a carbon atom, a hydrogen atom and an oxygen atom. ) And an olefin having a polycyclic hydrocarbon group represented by the following general formula (2) (In the formula, R ¹ , R ² and R ³ may be the same or different,
Each is a methyl group or a phenyl group, n is an integer of 0 to 15, m is an integer of 1 to 15, and n + m ≧ 3. The method for producing a cyclic silicone derivative according to any one of claims 1 to 7, wherein the hydrogencyclosiloxane represented by the formula (4) is reacted in the presence of a hydrosilylation catalyst.