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• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07D—HETEROCYCLIC COMPOUNDS
  • C07D405/00—Heterocyclic compounds containing both one or more hetero rings having oxygen atoms as the only ring hetero atoms, and one or more rings having nitrogen as the only ring hetero atom
  • C07D405/02—Heterocyclic compounds containing both one or more hetero rings having oxygen atoms as the only ring hetero atoms, and one or more rings having nitrogen as the only ring hetero atom containing two hetero rings
  • C07D405/12—Heterocyclic compounds containing both one or more hetero rings having oxygen atoms as the only ring hetero atoms, and one or more rings having nitrogen as the only ring hetero atom containing two hetero rings linked by a chain containing hetero atoms as chain links
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07D—HETEROCYCLIC COMPOUNDS
  • C07D309/00—Heterocyclic compounds containing six-membered rings having one oxygen atom as the only ring hetero atom, not condensed with other rings
  • C07D309/02—Heterocyclic compounds containing six-membered rings having one oxygen atom as the only ring hetero atom, not condensed with other rings having no double bonds between ring members or between ring members and non-ring members
  • C07D309/08—Heterocyclic compounds containing six-membered rings having one oxygen atom as the only ring hetero atom, not condensed with other rings having no double bonds between ring members or between ring members and non-ring members with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached to ring carbon atoms
  • C07D309/10—Oxygen atoms
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  • C09K19/00—Liquid crystal materials
  • C09K19/04—Liquid crystal materials characterised by the chemical structure of the liquid crystal components, e.g. by a specific unit
  • C09K19/06—Non-steroidal liquid crystal compounds
  • C09K19/34—Non-steroidal liquid crystal compounds containing at least one heterocyclic ring
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  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
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  • C09K19/00—Liquid crystal materials
  • C09K19/04—Liquid crystal materials characterised by the chemical structure of the liquid crystal components, e.g. by a specific unit
  • C09K19/06—Non-steroidal liquid crystal compounds
  • C09K19/34—Non-steroidal liquid crystal compounds containing at least one heterocyclic ring
  • C09K19/3402—Non-steroidal liquid crystal compounds containing at least one heterocyclic ring having oxygen as hetero atom
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
  • C09K19/00—Liquid crystal materials
  • C09K19/04—Liquid crystal materials characterised by the chemical structure of the liquid crystal components, e.g. by a specific unit
  • C09K19/06—Non-steroidal liquid crystal compounds
  • C09K19/34—Non-steroidal liquid crystal compounds containing at least one heterocyclic ring
  • C09K19/3441—Non-steroidal liquid crystal compounds containing at least one heterocyclic ring having nitrogen as hetero atom
• • C—CHEMISTRY; METALLURGY
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  • C09K19/00—Liquid crystal materials
  • C09K19/04—Liquid crystal materials characterised by the chemical structure of the liquid crystal components, e.g. by a specific unit
  • C09K19/42—Mixtures of liquid crystal compounds covered by two or more of the preceding groups C09K19/06 - C09K19/40
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
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  • C09K19/00—Liquid crystal materials
  • C09K19/52—Liquid crystal materials characterised by components which are not liquid crystals, e.g. additives with special physical aspect: solvents, solid particles
  • C09K19/58—Dopants or charge transfer agents
  • C09K19/586—Optically active dopants; chiral dopants
  • C09K19/588—Heterocyclic compounds
• • C—CHEMISTRY; METALLURGY
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  • C09K19/00—Liquid crystal materials
  • C09K19/04—Liquid crystal materials characterised by the chemical structure of the liquid crystal components, e.g. by a specific unit
  • C09K19/06—Non-steroidal liquid crystal compounds
  • C09K19/34—Non-steroidal liquid crystal compounds containing at least one heterocyclic ring
  • C09K19/3402—Non-steroidal liquid crystal compounds containing at least one heterocyclic ring having oxygen as hetero atom
  • C09K2019/3422—Non-steroidal liquid crystal compounds containing at least one heterocyclic ring having oxygen as hetero atom the heterocyclic ring being a six-membered ring

Definitions

• Optically active tetrahydropyran derivative Optically active tetrahydropyran derivative, liquid crystal composition containing the same, and liquid crystal device
• the present invention relates to an optically active tetrahydropyrano derivative, a liquid crystal composition containing the same, and a liquid crystal device. More specifically, the present invention relates to a novel liquid crystal material useful as a liquid crystal material used for a display device or an electro-optical device. The present invention relates to an optically active tetrahydropyran derivative, a liquid crystal composition containing the same, and a liquid crystal device.
• liquid crystal materials used for display devices are currently mainly nematic liquid crystals, and are based on TN-type or STN-type simple matrix methods using these and individual pixels.
• a TFT-type active matrix method with a thin-film transistor is used.
• the nematic liquid crystal has a disadvantage that the response speed is essentially slow (msec order) because the driving force is based on the anisotropy of the dielectric constant of the liquid crystal material and weak interaction with the electric field. Therefore, it is disadvantageous as a material for a large-screen display element requiring high-speed response.
• the desired performance can be obtained by mixing compounds having a plurality of SmC * phases or adding an optically active compound to a base liquid crystal having a low-viscosity smectic C phase (SmC phase).
• SmC phase low-viscosity smectic C phase
• It may or may not have an SmC * phase, and is required to have good compatibility with the base liquid crystal, induce large spontaneous polarization, and not increase the viscosity.
• ⁇ 71 Z (P s ⁇ E).
• Ps indicates spontaneous polarization
• E indicates electric field strength. Therefore, a liquid crystal material having a small viscosity and a large spontaneous polarization has been set as a development target in order to obtain a high-speed response.
• Spontaneous polarization is thought to result from the suppression of free rotation about the major axis of the dipole moment in the direction perpendicular to the major axis of the molecule due to the effect of asymmetric carbon. Therefore, in order to increase the spontaneous polarization, (1) the dipole part is called the core-closer to the skeleton, (2) closer to the dipole part and four asymmetric carbon atoms, and (3) sterically large to the asymmetric carbon. Attempts have been made to increase spontaneous polarization by adding substituents and suppressing free rotation about the long axis.
• the alignment state differs depending on the phase sequence of the liquid crystal material, and the isotropic phase (I so Phase) ⁇ Cholesteric phase (N * phase) Smectic A phase (Sm A phase) ⁇ Chiral smectic C phase (S m C * phase) Is preferred.
• the race pitch must be sufficiently long in the N * phase.
• the present inventors have investigated whether a novel compound having a fluoroalkyl group having a large electron withdrawing property on the asymmetric carbon atom on the tetrahydropyran ring exhibits liquid crystallinity as a single product. Or as a single product does not exhibit liquid crystallinity, but when it is used as a composition, it induces a large spontaneous polarization, exhibits a high-speed response, and is an excellent chiral dopant that can easily obtain good alignment. I found something like that. The present invention has been completed based on these findings. That is, the present invention provides a compound represented by the general formula (I):
• R f represents a Furuoroarukiru group having 1 or 2 carbon atoms
• R 1 is a linear or branched alkyl group having 3-2 0 carbon atoms
• R 2 is each independently X represents hydrogen or a linear or branched 'chain alkyl group having 1 to 15 carbon atoms, an alkenyl group having 2 to 15 carbon atoms or an aralkyl group having 7 to 10 carbon atoms
• X 1 represents one COO—, -0 C 0-or — represents a single compound
• X 2 represents one COO—,-0 C 0-, -CH 2 0 —.-0 CH 2 — or a single compound
• X 3 represents one C 00 —,-CH 20 — or 10 —
• X 4 represents 10 — or 10 C 0 —
• * represents an asymmetric carbon
• a and B are each independently
• n 0 or 1.
• Rf as described above represents a fluoroalkyl group having 1 or 2 carbon atoms, specifically, a trifluoromethyl group, Diphenylomethyl group, chlorodifluoromethyl group, pentafluoroethyl group, etc., and preferably trifluoromethyl group.
• R ' is a straight-chain or branched-chain alkyl group having 3 to 20 carbon atoms, for example, n-propyl group, isopropyl group, n-butyl group, isobutyl group sec-butynole group, te 1-t — butyl, n — pentyl, n — hexyl, n — heptyl, n — octyl.
• N nonyl
• n decyl
• n didecyl
• n dodecyl group
• n tridecyl group n-tetradecyl group
• n-pentadecyl group n-hexadecyl group
• n-heptadecyl group ⁇ -octadecyl group
• n-nonadecyl group n-eicosyl group.
• the branched alkyl group having an asymmetric carbon is an optically active group.
• R 2 and R 3 and R 4 are each independently hydrogen or a linear or branched alkyl group having 1 to 15 carbon atoms, such as a methyl group.
• N-heptyl group, 1-methylbutyl group N—octyl group, 1-ethylheptyl group. 1—methylyloctyl group.
• Alkenyl groups having 2 to 15 carbon atoms include vinyl group, aryl group, and i-propyl group. , Isopropenyl group, 1-butenyl group, 2-butenyl , 2-methylaryl group. 1 monopentenyl group, 1-hexenyl group.
• the aralkyl group having 10 to 10 carbon atoms include a benzyl group, a phenethyl group, a phenylpropyl group, and a phenylbutyl group.
• R f, R 2 , R 3 , R.X 4 and * are the same as described above, to obtain a compound of the above general formula (I) be able to.
• This reaction is carried out at 120 ° C to 80 ° C in a solvent such as toluene, benzene or methylene chloride in the presence of an organic base such as pyridin or triethylamine. It can be performed at the temperature of C.
• the compound represented by the general formula (I) can be obtained by reacting the compound represented by the general formula (II) with the compound represented by the general formula ((1). This reaction is carried out by reacting a compound represented by the general formula (11I) with an alkali metal hydride, sodium hydroxide or a base typified by a hydroxide power, and then reacting the compound represented by the general formula (IV) By adding the compound of formula (1).
• R 3 , R 4 and * are the same as above.
• This reaction is carried out in the presence of an organic base such as pyridinethylethylamine in a solvent such as toluene, benzene or methylene chloride at a temperature of ⁇ 20 ° C to 80 ° C. be able to.
• organic base such as pyridinethylethylamine
• solvent such as toluene, benzene or methylene chloride
• R f, B. X 4 , R 2 , R 3 , R 4 and * are the same as above.
• the compound represented by is produced.
• hydrogenolysis is performed at normal pressure using an alcoholic solvent such as methanol, ethanol, or propanol or acetic acid in the presence of a PdZC catalyst. This can be done.
• the compound of the above general formula (I) By reacting with the compound represented by the general formula (I), the compound of the above general formula (I) can be obtained.
• This reaction is carried out in a solvent such as toluene, benzene, methylene chloride or the like in the presence of an organic base such as pyridin. It can be performed at a temperature of
• T hp tetrahydroviranyl group
• B and Z are the same as those described above.
• This reaction is represented by the general formula (III)
• the reaction can be carried out by reacting a compound represented by the formula (IX) with sodium hydroxide or a base typified by sodium hydroxide, after reacting the compound with an alkali metal hydride. .
• the compound of the above general formula (I) can be obtained by reacting the obtained compound of the general formula (XI) with the compound of the above general formula (VIII).
• This reaction should be carried out in a solvent such as toluene, benzene or methylene chloride at a temperature of 120 ° C to 80 ° C in the presence of an organic base such as pyridine or triethylamine.
• a solvent such as toluene, benzene or methylene chloride at a temperature of 120 ° C to 80 ° C in the presence of an organic base such as pyridine or triethylamine.
• This reaction is carried out by reacting a compound represented by the general formula (III) with alkali metal hydride, sodium hydroxide, or a base represented by a hydroxylating hydride, followed by dimethylformamide.
• the reaction can be carried out by reacting a compound represented by the general formula (XII) with cuprous iodide as a catalyst under reflux conditions such as dimethyl sulfoxide and dimethyl sulfoxide. it can.
• R f. B, X 4 RR 3. R and * are the same as the above. ]
• the elimination of the tetrahydrobiranyl group is carried out in the presence of an acid catalyst such as hydrochloric acid, sulfuric acid and paratoluenesulfonate, in the presence of ether, tetrahydrofuran, or black form. It can be performed using a solvent.
• the compound of the above general formula (I) can be obtained by reacting the compound of the general formula (XIV) thus obtained with the compound of the above general formula (VIII). This reaction can be carried out in a solvent such as toluene, benzene, or methylene chloride at a temperature of ⁇ 20 ° C. to 80 ° C. in the presence of an organic base such as pyridin or triethylamine. it can.
• the compound represented by the above general formula ( ⁇ ) By reacting the compound represented by the formula, the compound represented by the above general formula ( ⁇ ) can be obtained.
• This reaction is carried out by reacting a compound represented by the general formula (VII) with an alkali metal hydride, sodium hydroxide or a base represented by a hydroxylating hydride.
• the reaction can be carried out by reacting the compound represented by
• R f .Z.B, X 4 , R 2 .R 3 , R 4 and * are the same as above. The same. ]
• This reaction is carried out in a solvent such as toluene, benzene or methylene chloride at a temperature of 120 ° C to 80 ° C in the presence of an organic base such as pyridinethylethylamine. It can be carried out.
• a solvent such as toluene, benzene or methylene chloride at a temperature of 120 ° C to 80 ° C in the presence of an organic base such as pyridinethylethylamine. It can be carried out.
• the compound represented by the general formula (I) By reacting the compound (XVII) with the compound represented by the formula (I), the compound represented by the general formula (I) can be obtained. This reaction is carried out by reacting a compound represented by the general formula (VIII) with an alkali metal hydride. Sodium hydroxide or a base represented by potassium hydroxide. ) Can be carried out by adding a compound represented by In addition, the compound of the general formula (I ′) according to the present invention can be produced by various methods. For example, it can be produced by the following steps.
• R f, R 2 , R 3 and * are as defined above.
• TBS represents t-butyldimethylsilyl group.
• the compound represented by the above general formula (XXIII) is a mixture of two diastereomers, but can be easily separated by silica gel column chromatography.
• the desired compound represented by the above (1 ') By reacting with the compound represented by the formula (1), the desired compound represented by the above (1 ') can be obtained.
• This reaction is carried out in a solvent such as toluene, benzene, methylene chloride, etc. in the presence of an organic base, eg, pyridin, tritylamine, etc., at a temperature of 120 ° C to 8 ° C. It can be performed at a temperature of 0 ° C.
• R 5 is a straight or branched alkyl group having 1 to 15 carbon atoms.
• An alkene having 2 to 15 carbon atoms. Represents an aralkyl group of ⁇ 10.
• This reaction can be performed without solvent or in a solvent such as tetrahydrofuran at 0 to 50 using, for example, paratoluenesulfonic acid as an acid catalyst.
• the desired compound represented by the above (1 ′) is obtained.
• This reaction is carried out in a solvent such as toluene, benzene or methylated chloride in the presence of an organic base such as pyridin or triethylamine in a solvent such as ⁇ 20 ° C. to 80 ° C. It can be performed at a temperature of
• This desilylation reaction can be carried out by various methods. For example, in a solvent of tetrahydrofuran, a catalyst is used. Using tetra-n-p-tinoleammonium fluoride, 0 to 50. You can do it in C.
• the compound represented by the general formula (XXXIII) is a mixture of two types of diastereomers, and is easily separated by silica gel chromatography chromatography. be able to.
• the desired compound represented by the above (1 ′) can be obtained. It can.
• This reaction is carried out in a solvent such as toluene, benzene, or methylene chloride at 120 ° C. in the presence of an organic base such as pyridin or triethylamine. It can be performed at a temperature of 80 ° C.
• B z represents a benzyl group, and B and Hal are as defined above.
• R f, R 2 , R 3. R, B and * are the same as above.
• the compound represented by these is obtained.
• This debenzylation reaction can be carried out by various methods, for example, in the presence of palladium-carbon (PdZC) catalyst, methanol, ethanol, propanol, etc. Hydrogenolysis at normal pressure using an alcohol solvent or acetic acid.
• PdZC palladium-carbon
• the compound represented by the general formula (I) of the present invention is produced, the compound represented by the general formula (III) used as a starting material can be produced by various methods. You. Representative examples of the compound represented by the general formula (III) include, for example,
• Examples of the compound of the general formula (I ′) of the present invention include, for example,
• optically active compound represented by the above general formula (I) or (I ') of the present invention has various stereoisomers since it has 3 to 5 asymmetric points. Therefore, the direction of the spontaneous polarization induced when added to the base liquid crystal and the direction of the N * crystal racen differ depending on the optically active compound, and there are various types as shown in Table 1.
• the N * phase spiral pitch (P) is 8 jK m (4 Times) or more is preferable. Since this racen pitch (P) decreases in inverse proportion to the amount of the optically active compound added, it is necessary to adjust the race pitch especially when the amount of the optically active compound added is large. At this time, it is preferable to mix compounds in which the sign of spontaneous polarization is the same and the direction of the helix of the N * phase is opposite so as not to impair the high-speed response. In particular, as the optically active tetrahydropyran derivative, it is preferable to use at least two kinds of compounds having the same spontaneous polarization sign and the opposite direction of the N * phase racene.
• the spiral pitch (P) of the mixed liquid crystal is
• (c) It can be obtained by blending a compound or mixture having a smectic C phase (SmC phase) other than (a).
• the compounding amount of the compound represented by the general formula (I) or (1 ′) may be appropriately selected according to various situations, but is preferably 0.1 to 99% of the obtained liquid crystal composition. % By weight, particularly preferably from 1 to 90% by weight.
• liquid crystal composition of the present invention a liquid crystal composition comprising at least two kinds of compounds represented by the general formula (I) or (I ′) can be mentioned. .
• the compound of the above (c) is preferably a compound of the general formula (A)
• R e is an alkyl group or an alkoxy group having 1 to 15 carbon atoms which may have a substituent
• R 7 is a carbon atom having 1 or more carbon atoms which may have a substituent.
• Q is 10-COO-, 1-OCO-OCOO- or single bond
• E is
• the liquid crystal element of the present invention is obtained by disposing the compound of the above general formula (I) or (I ′) or the above liquid crystal composition between a pair of electrode substrates.
• the liquid crystal element for example, I 11 0 3, S n 0 2, IT 0 on a transparent substrate having a transparent conductive electrode made of oxide (fin Jiumu mixed oxide of tin oxide), is Ranipo Li
• a cell is produced by bonding two pairs of substrates provided with an alignment control film made of vinyl alcohol or polyimide, and a polarizing plate is placed above and below the cell.
• This element has a birefringence mode and can be used as a display element or an electro-optical element.
• R and S of the optically active compound represented by the general formula (I) or (I ′) of the present invention are represented by the following formulas:
• Example 4 The same operation as in Example 3 was carried out using 0.53 g (1.8 mmol) of 1-hydroxysiloxane to obtain the desired compound (2S, 5R, GR) -te.
• Traffic 6 Trifluoro 2 — Hexinole 5 — (4 * — Hexyloxybif 2 4 '-Methylen) Pilane 0. 6 7 g (1.2 mmol) was obtained.
• Example 1 Was prepared as a base liquid crystal A comprising 25% by weight.
• the liquid crystal A was mixed with the liquid crystal A such that the optically active tetrahedral silane derivative obtained in Example 1 became 2 Hi jft% to prepare a liquid crystal composition.
• phase transition temperature of the obtained liquid crystal composition is as follows. 5'C 63 * C., 68 * C
• This liquid crystal composition was injected into a liquid crystal device having a cell orientation of 1.5 m and having a polyimide alignment film subjected to a parallel rubbing treatment in an isotropic phase.
• the response speed was determined as the time during which the transmitted light intensity under orthogonal Nicols changed from 0 to 90%.
• the spontaneous polarization value measured by the triangular wave method 2. was 7 n C cm 2.
• the optically active tetrahydropyran derivative obtained in Example 2 was mixed with the base liquid crystal A obtained in Example 15 so as to be 5% by weight to prepare a liquid crystal composition.
• the phase transition temperature of the obtained liquid crystal composition is as follows.
• the product is purified by silica gel chromatography with chromatographic chromatography, and the desired (5S, 6S) -tetrahydro-5-t-butyl-methyl thiocyanate is used.
• Methyl-2—hydroxypyran (6.4 g, 21 milliliters) was obtained.
• the compound obtained was a mixture of diastereomers having a molar ratio of 82:18 by nuclear magnetic resonance using an isotope of fluorine.
• the physical properties of the obtained compound are shown below.
• Example 2 Using 0.13 g (0.3 millimol) of the (2S.5R, 6R) alcohol compound having an asymmetric carbon obtained by the operation of Example 20 (b), Example 20 By performing the same operation as in 20 (c), the desired compound (2S, 5R.6R) -tetrahydro-6-trif-noreolo-methinole-5-hexano 0.13 g (0.2 millimoles) of pyridine 2-(4'-l-heptylbifluor 4'-methylenoxy) pyran was obtained.
• Example 17 (b) 0.37 g (0.8 mmol) of the (2S.5R.6R) alcohol compound having an asymmetric l-synthesis obtained by the operation of Example 17 (b) and acetone
• Example 17 (c) The same operation as in Example 17 (c) was carried out using 0.07 milliliters of chlorchloride (1.0 millimoles) to obtain the desired compound (2R, 5R 6 R) Tetrahedro 5 — Acetoxy 6 — Trifnoreo rometyl-2-(4 ⁇ 1 ⁇ ⁇ ⁇ ⁇ ⁇ 4 ⁇ 1 ⁇ ⁇ ) 0.39 g (0.8 mimol) of pyran was obtained.

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• 1992
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