JP3013144B2 - Silacyclohexane compound, method for producing the same, and liquid crystal composition containing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel silacyclohexane compound, a method for producing the same, a liquid crystal composition containing the compound, and a liquid crystal display device containing the liquid crystal composition.

[0002]

2. Description of the Related Art A liquid crystal display device utilizes an optical anisotropy and a dielectric anisotropy of a liquid crystal material. Depending on the display mode, a TN type (twisted nematic type), an STN type (super twisted nematic type), SBE type (super birefringent type), DS
There are various types such as a type (dynamic scattering type), a guest-host type, a DAP type (an alignment phase deformation type), and an OMI type (optically mode interference type). The most common display devices are based on the Schadt-Helfrich effect and have a twisted nematic structure.

The properties required of the liquid crystal material used in these liquid crystal displays slightly vary depending on the display system, but the liquid crystal temperature range is wide, and the liquid crystal material is stable against moisture, air, light, heat, an electric field, and the like. This is commonly required in any of the display methods. Further, it is desired that the liquid crystal material has a low viscosity and provides a short address time, a low threshold voltage and a high contrast in the cell.

At present, there is no substance that satisfies all of these requirements with a single compound. In practice, a liquid crystal mixture obtained by mixing several to several tens of liquid crystal compounds and latent liquid crystal compounds is used. . Therefore, it is an important characteristic that the components of the liquid crystal composition can be easily mixed with each other.

[0005] Liquid crystal compounds which can be these constituents can be classified as follows when classified according to their functions. Compound that contributes to viscosity reduction and melting point drop of mixed liquid crystal composition Compound that mainly controls electro-optical function of mixed liquid crystal composition Compound that contributes to increase of clearing point of mixed liquid crystal composition Refractive anisotropy of mixed liquid crystal composition Compound that contributes to control Compound that controls color display and alignment of mixed liquid crystal composition

[0006] Of these classes, compounds belonging to

Embedded image (Japanese Patent Publication No. 56-38146),

Embedded image (Japanese Patent Publication No. 64-373),

Embedded image (Japanese Patent Publication No. 38772/1989), etc., have been known compounds having a so-called PCH structure.

[0007]

In recent years, as the applications of liquid crystal displays have expanded, the characteristics required for liquid crystal materials have become increasingly severe and strict. In particular, improved low-temperature performance, widened temperature range to meet automotive needs,
In terms of lowering the driving voltage and the like, it has been desired to further improve the characteristics of the conventional liquid crystal material.

[0008] From such a viewpoint, the present invention, in particular,
A liquid crystal material newly developed for the purpose of reducing the viscosity of the mixed liquid crystal composition and improving the properties of the compound contributing to the melting point effect, and having a silacyclohexane ring completely different from the liquid crystal compound having a PCH structure, which is a conventional technology. It is intended to provide a novel liquid crystal compound.

[0009]

That is, the present invention provides a silacyclohexane compound represented by the following general formula (I).

Embedded image In the formula, R is a linear alkyl group having 1 to 10 carbon atoms, a branched chain alkyl group having 3 to 8 carbon atoms, 2 to 7 carbon atoms.
Represents an alkoxyalkyl group or an alkenyl group having 2 to 8 carbon atoms.

Embedded image Is trans-1-silacyclohexylene or trans- in which silicon at the 1- or 4-position has a substituent of H, F or Cl.
Represents a 4-silacyclohexylene group. X is CN, F,
Cl, CF ₃ , CF ₂ Cl, CHFCl, OCF ₃ , O
Represents a CHF ₂ , OCF ₂ Cl, OCHFCl, R or OR group. Y represents H or F. Z represents H or F.

The present invention also relates to an organometallic reagent RM (M represents MgP (P represents halogen), ZnP or Li) and a silacyclohexane compound

Embedded image (W represents H, F or Cl; Q represents a halogen or an alkoxy group. )

(2) Is a method for producing a silacyclohexane compound.

[0011] The present invention also relates to an organometallic reagent.

Embedded image And a silacyclohexane compound

Embedded image (Where M is MgP (P represents halogen), ZnP
Or, Li and W represent H, F or Cl. Q is haloge
And an alkoxy group. ) And the general formula by the reaction of
(3)

Embedded image (3) Is a method for producing a silacyclohexane compound.

The present invention also relates to an organometallic reagent.

Embedded image (M ′ is MgP ′ (P ′ represents Br or I), Zn
Or, Li and X ′ represent halogen. ) And a silacyclohexane compound

Embedded image Phenylsilacyclohexane compound obtained by the reaction with

Embedded image (W represents H, F or Cl. Q represents halogen
And an alkoxy group. The general formula (4) obtained by reacting the Grignard reagent of the above ) with a cyanating agent

(4) Is a method for producing a silacyclohexane compound.

Further, the present invention provides a liquid crystal composition containing the silacyclohexane compound represented by the above general formula (I) and a liquid crystal display device containing this liquid crystal composition.

The novel compound represented by the general formula (I) is
Specifically, it is a novel silacyclohexane compound represented by the following ring structure [Chemical Formula 20] or [Chemical Formula 21] and having a ring structure including a trans-1 or 4-silacyclohexane ring.

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In the formula, R is a linear alkyl group having 1 to 10 carbon atoms, ie, methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl, n-
Octyl, n-nonyl, n-decyl group; or 3 carbon atoms
~ 8 branched alkyl groups, i.e., isopropyl, sec.
-Butyl, isobutyl, 1-methylbutyl, 2-methylbutyl, 3-methylbutyl, 1-methylpentyl, 2-
Methylpentyl, 3-methylpentyl, 1-ethylpentyl, 1-methylhexyl, 2-methylhexyl, 3-
Methylhexyl, 2-ethylhexyl, 3-ethylhexyl, 1-methylheptyl, 2-methylheptyl, 3-
Methylheptyl; or an alkoxyalkyl group having 2 to 7 carbon atoms, that is, methoxymethyl, ethoxymethyl, propoxymethyl, butoxymethyl, pentoxymethyl, hexyloxymethyl, methoxyethyl, ethoxyethyl, proxyethyl, butoxyethyl, pentoxy Ethyl, methoxypropyl, ethoxypropyl, propoxypropyl, butoxypropyl, methoxybutyl, ethoxybutyl, propoxybutyl, methoxypentyl, ethoxypentyl; or an alkenyl group having 2 to 8 carbon atoms, i.e., vinyl, 1-propenyl, allyl, 1-butenyl, 3-butenyl, isobutenyl, 1-pentenyl, 3-pentenyl, 4-pentenyl, dimethylallyl, 1-hexenyl, 3-hexenyl, 5-hexenyl, 1-heptenyl, 3-heptenyl, - represents heptenyl, 7-octenyl group.

W represents H, F or Cl.

X is CN, F, Cl, CF ₃ , CF ₂ C
1, CHFCl, OCF ₃ , OCHF ₂ , OCF ₂ C
1, represents OCHFCl, R or OR group.

Y represents H or F. Z is H or F
Represents

[0019]

Embedded image Specific examples include the following groups.

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R represents a linear alkyl group having 3 to 7 carbon atoms, that is, n-propyl, n-butyl, n-pentyl,
n-hexyl, n-heptyl group, or a branched alkyl group having 3 to 7 carbon atoms, isopropyl, 1-methylpropyl, 2-methylpropyl, 1-methylbutyl, 2-methylbutyl, 3-methylbutyl, Methylpentyl, 2
-Methylpentyl, 2-ethylhexyl group, or an alkoxyalkyl group having 2 to 6 carbon atoms, i.e., methoxymethyl, methoxyethyl, methoxypropyl, methoxypentyl, ethoxymethyl, ethoxyethyl, propoxymethyl, pentoxymethyl group, or Of the alkenyl groups, vinyl, 1-propenyl, 3-butenyl, 1-pentenyl, 3-pentenyl, 4-pentenyl, 1-hexenyl, 5-hexenyl, 6-heptenyl and 7-octenyl groups are practically desirable.

As for W, H and F are practically desirable. However, when the ring structure of the silacyclohexane ring is
1] and when X is a compound of CN, W is limited to H.

Regarding [Chemical formula 22], [Chemical formulas 23 to 26], [Chemical formula 29], [Chemical formulas 32] to [Chemical formula 37], [Chemical formula 4]
1], [Formula 44] to [Formula 49], [Formula 52] to [Formula 5]
5] is practically preferable.

Next, methods for producing these compounds will be described.

(1) A method for producing the compound of the present invention wherein the ring structure of the silacyclohexane ring is [Chemical Formula 21] and X is CN. In this production method, p-halobromobenzene or p-haloiodobenzene having Y and Z substituents is reacted with magnesium in a solvent such as THF (tetrahydrofuran) to obtain a corresponding Grignard reagent. Next, silicon is reacted with a silacyclohexane compound substituted with W and Q. Thereafter, the metal magnesium is further reacted in a solvent such as THF (tetrahydrofuran) to prepare a Grignard reagent, and then reacted with a cyanating agent such as cyanogen. Since the compound formed here is a mixture of a trans form and a cis form in the conformation of the silacyclohexane ring, the trans form is separated and purified by a conventional purification means such as chromatography or recrystallization. A silacyclohexane compound represented by the general formula (I) is obtained. The reaction formula is shown below.

[0025]

Embedded image (P: Br or I, X ': halogen, Q: halogen or alkoxy group)

(2) A method for producing the compound of the present invention other than the above (1). Although the reaction substrates are slightly different depending on the ring structure, they are commonly produced by a coupling reaction of an organometallic reagent shown below.

In this production method, a corresponding organometallic reagent is prepared from R-halide or substituted aryl halide in a solvent such as THF (tetrahydrofuran) by a conventional method. The resulting organometallic reagent is then reacted with a silacyclohexane compound in which silicon has been replaced by W and Q. Since the compound formed here is a mixture of a trans form and a cis form in the conformation of the silacyclohexane ring, the trans form is separated and purified by a conventional purification means such as chromatography or recrystallization. A silacyclohexane compound represented by the general formula (I) is obtained. The reaction formula is shown below.

[0028]

Embedded image

Embedded image ｛M is MgP ₁ (P ₁ represents halogen), ZnP ₁
Alternatively, Li and M ′ represent Mg (P ₂ represents Br, I (when X is Cl) or Cl, Br, I (if X is not Cl)), ZnP ₂ or Li. Q represents a halogen or an alkoxy group, and W represents H, F or Cl. X is
CN, F, Cl, CF ₃ , CF ₂ Cl, CHFCl, O
CF ₃ , OCHF ₂ , OCF ₂ Cl, OCHFCl, R
Or an OR group. Y represents H or F. Z represents H or F. However, when W = F or Cl, W = Q. ｝

The liquid crystal composition can be obtained by mixing the silacyclohexane compound of the present invention with a known compound.
Specifically, a liquid crystal composition can be obtained by mixing with the following compounds.

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In the chemical formulas (59) and (60), (M) and (N) are unsubstituted or 1
Trans-1,4-cyclohexylene group having one or more F, Cl, Br, CN, alkyl groups, one or two non-adjacent CHs in a cyclohexane ring
A ring in which _two groups are replaced by O, S, a 1,4-cyclohexenylene group, 1,4-phenylene unsubstituted or having one or two F, Cl, CH ₃ or CN groups as substituents In the groups 1,4,4-phenylene, one or two CH groups in the ring represent any of the rings replaced by N atoms.

Z ¹ and Z ² represent —CH ₂ CH ₂ —, —C
H = CH -, - C≡C - , - CO 2 -, - OCO -, -
Represents CH ₂ O—, —OCH ₂ — or a single bond.

L (L), m = 0, 1, 2 (where l +
m = 1, 2, 3, n = 0, 1, 2).

R is hydrogen, a linear alkyl group having 1 to 10 carbon atoms, a branched alkyl group having 3 to 8 carbon atoms,
To 7 alkoxyalkyl groups or alkenyl groups having 2 to 8 carbon atoms.

X, Y and Z are the same as defined in the general formula (I).

In the above description, l (ell), n = 2
In the case of (M), a heterocyclic ring may be contained in (M), and when m = 2, in (N).

The ratio of the silacyclohexane compound of the present invention in the liquid crystal composition may be one or two or more.
The content is 50% by weight, preferably 5 to 30% by weight. Further, the liquid crystal composition may contain a polychromatic dye for generating a colored guest-host system or an additive for changing the dielectric anisotropy, viscosity, and alignment of the nematic phase.

Various liquid crystal display devices can be manufactured by a usual method using the liquid crystal composition thus formed. That is, the liquid crystal composition containing the silacyclohexane compound of the present invention is sealed between transparent substrates having electrodes of a desired shape and used as a liquid crystal display device. This element may have various undercoats, an overcoat for orientation control, a polarizing plate, a filter, a reflective layer, and the like, if necessary. Various types using a light source or the like can be used.

The driving method of the liquid crystal display element is a dynamic scattering (DSM) method, a twisted nematic (TN) method, a guest host (GH) method, a super twisted nematic (STN) method, a polymer dispersed liquid crystal (PDLC) method. For example, a method known in the liquid crystal display element industry can be employed.

[0039]

The present invention will be described below in more detail with reference to specific examples.

Example 1 Preparation of 4- (trans-4-n-heptyl-4-silacyclohexyl) benzonitrile 0.5 g (21 mmol) of magnesium and 50 of THF
3.6 g of 1-bromo-n-heptane in a mixture of ml
(20 mmol) was added dropwise to obtain a Grignard reagent. This was added to a mixture of 2.8 g of zinc chloride and 20 ml of THF to obtain an organozinc reagent. Subsequently, this solution was added to 4- (4
-Chloro-4-silacyclohexyl) benzonitrile was added dropwise to a solution of 4.7 g (20 mmol) of THF in 50 ml of THF to obtain 4- (4-n-heptyl-4-silacyclohexyl) benzonitrile. This is a mixture of a trans form and a cis form with respect to the silacyclohexane ring,
Separated by chromatography, the trans form 5.5
g (yield 92%). CN transition temperature: 16 ° C., NI transition temperature: 19 ° C. IR (liquid film) νmax: 2920, 2227, 2100, 1608, 1502, 1458, 1408, 1184, 987, 893, 889, 820 cm ⁻¹

The following compounds were obtained in the same manner as in Example 1.

Example 2 4- (trans-4-n-pentyl-4-silacyclohexyl) benzonitrile CI transition temperature: 38 ° C., NI transition temperature: 13 ° C. IR (liquid film) νmax: 2920, 2227, 2104, 1608, 1502, 1458, 1408, 987, 881, 825 cm ^-1

Example 3 4- (trans-4-n-hexyl-4-silacyclohexyl) benzonitrile CI transition temperature: 18 ° C., NI transition temperature: 10 ° C. IR (liquid film) νmax: 2920, 2227, 2100, 1608, 1502, 1458, 1407, 1184, 987, 889, 879, 817 cm ^-1

Example 4 4- (trans-4-n-nonyl-4-silacyclohexyl) benzonitrile CI transition temperature: 32 ° C., NI transition temperature: 25 ° C. IR (liquid film) νmax: 2916, 2225, 2090, 1606, 1502, 1470, 1406, 989, 933, 889, 812 cm ^-1

Example 5 Production of 4- (trans-4-n-heptyl-4-silacyclohexyl) -1,2-difluorobenzene 0.5 g (21 mmol) of magnesium and THF50
3.0 g of 1-bromo-n-heptane (2
0 mmol) was added dropwise to obtain a Grignard reagent. Subsequently, 4.9 g of 4- (4-chloro-4-silacyclohexyl) -1,2-difluorobenzene (20 mm
ol) in 50 ml of THF.
(Heptyl-4-silacyclohexyl) -1,2-difluorobenzene was obtained. This was a mixture of a trans form and a cis form with respect to the silacyclohexane ring, and was separated by chromatography to obtain 5.3 g (yield: 93%) of the trans form. CI transition temperature: -17 ° C IR (liquid film) νmax: 2920, 2102, 1517, 1431, 1407, 1284, 1213, 1114, 987, 960, 889, 811 cm ^-1

The following compounds were obtained in the same manner as in Example 5.

Example 6 4- (trans-4-n-heptyl-4-silacyclohexyl) -1-fluorobenzene CI transition temperature: 11 ° C. IR (liquid film) νmax: 2920, 2100, 1510, 1458, 1408, 1228, 985, 887, 820 cm ^-1

Example 7 4- (trans-4-n-pentyl-4-silacyclohexyl) -1-fluorobenzene CI transition temperature: 2 ° C. IR (liquid film) νmax: 2920, 2100, 1510, 1458, 1408, 1228, 987, 887, 825 cm ^-1

Example 8 4- (trans-4-n-hexyl-4-silacyclohexyl) -1-fluorobenzene CI transition temperature: 8 ° C. IR (liquid film) νmax: 2920, 2100, 1510, 1458, 1408, 1228, 1159, 987, 887, 816 cm ^-1

Example 9 4- (trans-4-n-pentyl-4-silacyclohexyl) -1-chlorobenzene CI transition temperature: 9 ° C. IR (liquid film) νmax: 2920, 2110, 1495, 1465 , 1415, 1095, 990, 880, 815 cm ^-1

Example 10 4- (trans-4-n-hexyl-4-silacyclohexyl) -1-chlorobenzene CI transition temperature: 35 ° C. IR (liquid film) νmax: 2920, 2100, 1495, 1460 , 1410, 1180, 1095, 985, 880, 805 cm ^-1

Example 11 4- (trans-4-n-heptyl-4-silacyclohexyl) -1-chlorobenzene CI transition temperature: 23 ° C. GC-MS (70 eV) (m / e) ⁺ : 127 , 154, 209, 252, 280, 308

Example 12 4- (trans-4-n-octyl-4-silacyclohexyl) -1-chlorobenzene CI transition temperature: 43 ° C. IR (KBr) νmax: 2920, 2100, 1495, 1460, 1410, 1090, 985, 880, 805 cm ^-1

Example 13 4- (trans-4-n-nonyl-4-silacyclohexyl) -1-chlorobenzene CI transition temperature: 41 ° C. IR (liquid film) νmax: 2925, 2100, 1495, 1460 , 1410, 1095, 990, 880, 815 cm ^-1

Example 14 4- (trans-4-n-heptyl-4-silacyclohexyl) -1-trifluoromethoxybenzene

Example 15 4- (trans-4-isopentyl-4-silacyclohexyl) -1-methoxybenzene

Example 16 4- (trans-4-methoxypentyl-4-fluoro-4-silacyclohexyl) -1-chloro-2-fluorobenzene

Example 17 4- (trans-4- (3-methoxypropyl) -4
—Silacyclohexyl) -1-fluorobenzene CI transition temperature: 5.9 ° C. IR (liquid film) νmax: 2922, 2852, 2100, 1604, 1508, 1225, 1117, 887, 818 cm ⁻¹

Example 18 4- (trans-4- (E-3-hexenyl) -4-
(Silacyclohexyl) -1-fluorobenzene CI transition temperature: -9.0 ° C IR (liquid film) νmax: 2962, 2916, 2102, 1604, 1510, 1228, 1159, 966, 887, 818 cm ^-1

Example 19 4- (trans-4- (3-methylbutyl) -4-silacyclohexyl) -1-fluorobenzene CI transition temperature: 5.7 ° C. IR (liquid film) νmax: 2954, 2916, 2100, 1606, 1510, 1228, 1159, 987, 889, 812 cm ^-1

Example 20 4- (trans-4-n-pentyl-4-silacyclohexyl) -2,3-difluoro-1-ethoxybenzene

Example 21 Preparation of 4- (trans-4-n-pentyl-1-silacyclohexyl) benzonitrile 0.5 g (21 mmol) of magnesium and 50 of THF
3.8 g of 4-bromochlorobenzene was added to the mixture of ml.
(20 mmol) in 5 ml of THF was added to obtain a Grignard reagent. Subsequently, this was added to 4-n-pentyl-1-
4.1 g of chloro-1-silacyclohexane (20 mmol
l) was added dropwise to a THF (50 ml) solution to give 4- (4-n-
5.5 g (97% yield) of pentyl-1-silacyclohexyl) chlorobenzene were obtained. Next, the resulting 4- (4-n-pentyl-1-silacyclohexyl) chlorobenzene was added to a mixture of 0.5 g (21 mmol) of magnesium and 50 ml of THF to obtain a Grignard reagent. This was added to an ether solution of 1.6 g of cyanodiene (CN) ₂ to obtain 4- (4-n-pentyl-1-silacyclohexyl) benzonitrile. This was a mixture of a trans form and a cis form with respect to the silacyclohexane ring, and was separated by chromatography to obtain 4.5 g of the trans form (yield 90%). ¹ H-NMR (100 MHz, CDCl ₃ ) δ: 0.30 (s, 3H), 0.75 to 1.00 (m, 7H), 1.10 to 1.40 (m, 10H), 1.60 ２．１2.10 (m, 3H), 7.60 (s, 4H) IR (liquid film) νmax: 2924, 2229, 1385, 1252, 1101, 985, 810, 775 cm ⁻¹

Example 22 Preparation of 4- (trans-4-isopentyl-1-silacyclohexyl) -1-trifluoromethylbenzene. 0.5 g (21 mmol) of magnesium and THF50
4.5 g (20 mmol) of 4-bromo-1-trifluoromethylbenzene was added dropwise to the mixture of ml to obtain a Grignard reagent. Subsequently, the solution was treated with 4-isopentyl-1-
4.1 g of chloro-1-silacyclohexane (20 mmol
1) was added dropwise to a solution of 50 ml of THF to obtain 4- (4-isopentyl-1-silacyclohexyl) -1-trifluoromethylbenzene. This is a mixture of a trans-isomer and a cis-isomer with respect to the silacyclohexane ring.
2%).

The following compounds were obtained in the same manner as in Example 22 .

Example 23 4- (trans-4-methoxypentyl-1-silacyclohexyl) -1-difluoromethoxybenzene

Next, the compound of the present invention obtained in the above example was added to an existing liquid crystal composition to produce a liquid crystal composition of the present invention. Then, the operation threshold voltage and the viscosity at 20 ° C. of the obtained liquid crystal composition were measured.

"Examples of Liquid Crystal Composition" 4- (4- (trans-4-ethylcyclohexyl)
-Trans-4-cyclohexyl) -1,2-difluorobenzene 40 mol%, 4- (4- (trans-4
-N-propylcyclohexyl) -trans-4-cyclohexyl) -1,3-difluorobenzene 35 mol% and 4- (4- (trans-4-n-pentylcyclohexyl) -trans-4-cyclohexyl)-
Mixture A comprising 25 mol% of 1,2-difluorobenzene exhibits the following properties. CN transition temperature: 7 ° C NI transition temperature: 106 ° C Threshold voltage: 2.50 V Viscosity (20 ° C): 26 cp

The mixture comprising 85% of this mixture A and 15% of 4- (trans-4-n-hexyl-4-silacyclohexyl) -1-fluorobenzene obtained in Example 8 exhibits the following properties. CN transition temperature: 2 ° C NI transition temperature: 81 ° C Threshold voltage: 2.30 V Viscosity (20 ° C): 19.7 cp

[0069]

When the substituent X is CN, the silacyclohexane compound of the present invention has a strong tendency to show a tautomeric phase transition.
In addition, when the substituent X is other than CN, most of them show a single phase change or a crystal-isotropic liquid type transition, and do not show electro-optical properties as a liquid crystal alone, When used as a liquid crystal composition together with a liquid crystal compound, it exhibits functions of reducing viscosity and lowering the melting point.

When the liquid crystal compound of the present invention into which Si is introduced as a ring constituent element is used as a constituent of a liquid crystal composition, the viscosity can be reduced, the response speed can be improved, and the compatibility at low temperatures can be improved. improves.

A liquid crystal compound in which X in formula (I) is not R or OR has the effect of lowering the threshold voltage due to the large dielectric anisotropy in addition to the above-mentioned advantages.

A liquid crystal compound in which the substituent X in the general formula (I) is R or OR has a dielectric anisotropy close to 1 zero.
It is preferably used for a liquid crystal phase of a display solution based on dynamic scattering (DS) or deformation of the alignment phase (DAP effect). Also,
Compounds other than X are preferably used for producing a liquid crystal phase having a large positive dielectric anisotropy for use in a display element based on a twisted nematic cell or a cholesteric-nematic phase transition.

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Tsuyoshi Kanesu 28, Nishifukushima, Oaza, Kushiro-mura, Nakakushiro-gun, Niigata Pref. Shin-Etsu Chemical Co., Ltd. Synthetic Technology Research Laboratories (72) Inventor Tatsushi Kaneko Nakatsuku-gun, Niigata 28, Nishifukushima, Kushiro-mura, Japan-1 Synthetic Technology Research Laboratory, Shin-Etsu Chemical Co., Ltd. ) Inventor Eiji Kurihara 28 Nishifukushima, Oku-ku, Kushiro-mura, Nakakibigusuku-gun, Niigata Pref. Shin-Etsu Chemical Co., Ltd., Synthetic Technology Laboratory (56) References JP-A-2-91080 (JP, A) JP-A-6-9653 (JP, A) Tokuhyo Hei 6-504784 (JP, A) Am. Chem. Soc. Bull., 94 [14] (1972), 5080-5082. Chem. Soc. Jpn. , 49 [11] (1976), 3185-3189. Eaborn, "ORGANOS ILICON COMPUNDS", (1960) BUTTERWORTHS CIENTIFIC PUBLICAT IONS, pp. 10-21. (58) Fields investigated (Int. Cl. ⁷ , DB name) C07F 7/08 C07F 7/10 C07F 7 / 12 C09K 19/40 CAPLUS (STN) REGISTRY (STN) WPIDS (STN)

Claims (6)

(57) [Claims] 1. A silacyclohexane compound represented by the following general formula (I). Embedded image In the formula, R is a linear alkyl group having 1 to 10 carbon atoms, a branched chain alkyl group having 3 to 8 carbon atoms, 2 to 7 carbon atoms.
Represents an alkoxyalkyl group or an alkenyl group having 2 to 8 carbon atoms. Embedded image Is trans-1-silacyclohexylene or trans- in which silicon at the 1- or 4-position has a substituent of H, F or Cl.
Represents a 4-silacyclohexylene group. X is CN,
F, Cl, CF ₃ , CF ₂ Cl, CHFCl, OC
Represents a F ₃ , OCHF ₂ , OCF ₂ Cl, OCHFCl, R or OR group. Y represents H or F. Z represents H or F. 2. An organometallic reagent RM (M represents MgP (P represents halogen), ZnP or Li) and a silacyclohexane compound (W is H, .Q representing F or Cl is a halogen, an alkoxy group.) In formula by reaction with (2) embedded image (2) The method for producing a silacyclohexane compound of the above. 3. An organometallic reagent And a silacyclohexane compound (Where M is MgP (P represents halogen), ZnP
Or, Li and W represent H, F or Cl. Q is haloge
And an alkoxy group. ) And the general formula by the reaction of
(3) embedded image (3) The method for producing a silacyclohexane compound of the above. 4. An organometallic reagent (M ′ is MgP ′ (P ′ represents Br or I), Zn
P 'or Li, X' represents halogen. ) And a silacyclohexane compound Phenylsilacyclohexane compound obtained by the reaction with (W represents H, F or Cl. Q represents halogen
And an alkoxy group. )) The general formula (4) obtained by reacting the Grignard reagent with a cyanating agent. The method for producing a silacyclohexane compound of the above. 5. A liquid crystal composition comprising the silacyclohexane compound according to claim 1. 6. A liquid crystal display device comprising the liquid crystal composition according to claim 5.