JP2001354601A - Method for manufacturing fluorotetrahydronaphthalene derivative - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a fluorotetrahydronaphthalene derivative for liquid crystal display easily on an industrial scale at a low cost. SOLUTION: The method for manufacturing a fluorotetrahydronaphthalene derivative of general formula II comprises the hydrogenation reduction of a fluoronaphthalene derivative of general formula I. The example includes the method of formula 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the production of fluorotetrahydronaphthalene useful as a liquid crystal display material.

[0002]

2. Description of the Related Art Liquid crystal display elements have been used in various measuring instruments such as watches and calculators, panels for automobiles, word processors, electronic organizers, printers, computers, televisions and the like. Typical liquid crystal display methods are TN (twisted nematic), STN (super twisted nematic), DS (dynamic light scattering), GH (guest / host), and FLC that can respond at high speed. (Ferroelectric liquid crystal)
And AFLC (antiferroelectric liquid crystal). As a driving method, a multiplex driving has been generally used instead of the conventional static driving, and a simple matrix method, more recently, an active matrix method has been put to practical use.

As the liquid crystal material used for these, a great variety of liquid crystal compounds have been synthesized so far, and these are used according to the display system, the driving system, or the application. However, demands for improving the performance of liquid crystal display elements (improvement of display quality, enlargement of display screen, etc.) are increasing year by year, and new liquid crystal compounds are being developed to satisfy the demands.

A liquid crystal compound is usually composed of a central skeleton part called a core and terminal parts on both sides. Usually, the ring structure constituting the core portion of the liquid crystal compound includes a 1,4-phenylene group (which may be substituted with one or two halogen atoms, a cyano group, a methyl group, or the like) and a trans-
The 1,4-cyclohexylene group accounts for the majority. However, liquid crystal compounds composed only of 1,4-phenylene group and trans-1,4-cyclohexylene group have limited types and properties, and it is impossible to meet the above requirements only with them. It is a fact.

The ring structure other than the 1,4-phenylene group and the trans-1,4-cyclohexylene group includes, for example, pyridine-
Heterocyclic systems such as 2,5-diyl group, pyrimidine-2,5-diyl group, 1,3-dioxane-trans-2,5-diyl group, and trans
-Decahydronaphthalene-2,6-diyl group, naphthalene-2,6
-Diyl group, 1,2,3,4-tetrahydronaphthalene-2,6-diyl group, bicyclo [2.2.2] octane-1,4-diyl group, spiro
[3.3] Condensed ring systems such as heptane-2,6-diyl group are also being studied, but are currently in practical use due to problems in production (technology, cost, etc.) and stability problems. Things are only a few.

The present inventors have proposed compounds (IIIa)

Embedded image

And (IIIb)

Embedded image Developed new fluorine-substituted tetrahydronaphthalene derivatives and reported that they show very excellent electro-optical properties and are particularly useful for the effect of reducing the threshold voltage (Vth) (Japanese Patent Application No. 191670).

However, since the yield in producing these compounds is not sufficiently high, they cannot be said to be compounds which can be obtained at low cost in terms of production cost. Therefore, an easy and inexpensive method for producing a fluorine-substituted tetrahydronaphthalene derivative is required.

[0009]

An object of the present invention is to provide an easy and inexpensive method for producing a fluorine-substituted tetrahydronaphthalene derivative.

[0010]

Means for Solving the Problems As a result of diligent studies to solve the above problems, the present invention has found that a fluorotetrahydronaphthalene derivative can be easily obtained by hydrogenating and reducing a fluoronaphthalene derivative.
The present invention has been completed.

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

Embedded image(Where R¹Is one or more fluorine atoms and / or carbon
Substituted by an alkoxyl group having 1 to 7 atoms
Or a saturated or unsaturated carbon which may contain a branched chain
Represents an alkyl group of Formulas 1 to 20, and a connecting group L¹Is a single bond, -CH_Two
CH_Two-, -CH = CH-, -CH (CH_Three) CH_Two-, -CH_TwoCH (CH_Three)-, -CH (C
H_Three) CH (CH_Three)-, -C≡C- or-(CH_Two)_Four-Represents a linking group M¹
And Q¹Are each independently a single bond, -CH_TwoCH_Two-, -CH = CH
-, -CH (CH_Three) CH_Two-, -CH_TwoCH (CH_Three)-, -CH (CH_Three) CH (CH_Three)-,-
C≡C-,-(CH_Two)_Four-, -COO-, -OCO-, -CH _TwoO- or -OCH_Two
And ring A, ring B and ring C are each independently trans
1,4-cyclohexylene group, trans-decahydronaph
Taren-2,6-diyl group, trans-1,3-dioxane-2,5-
Diyl group, bicyclo [2.2.2] octane-1,4-diyl group or
Is 1,4-phenylene which may be substituted by 1 to 2 fluorine atoms
Group, pyridine-2,5-diyl group, pyrimidine-2,5-diyl
Group, pyrazine-2,5-diyl group or pyridazine-3,6-di
And m and n are each independently 0 or 1
And X¹, X^TwoAnd X^ThreeAre each independently a hydrogen atom
Or a fluorine atom, Z¹Represents a hydrogen atom, a fluorine atom,
Trifluoromethoxy group, difluoromethoxy group or 1
Not less than 1 fluorine atom and / or 1 to 7 carbon atoms
A branched chain which may be substituted by an alkoxyl group;
A saturated or unsaturated C 1-20 alkyl which may contain
Represents a kill group. Where X¹, X^TwoAnd X^ThreeAre all hydrogen sources
Except when it is a child. ) Fluoronaphthalene represented by
A compound represented by the general formula (I)
I)

[0012]

Embedded image (Wherein, R ² may be substituted by one or more fluorine atoms and / or alkoxyl groups having 1 to 7 carbon atoms, and includes a saturated alkyl group having 1 to 20 carbon atoms which may contain a branched chain. And the linking group L ² is a single bond, -CH ₂ CH _2- , -CH (CH
₃ ) CH _2- , -CH ₂ CH (CH ₃ )-, -CH (CH ₃ ) CH (CH ₃ )-, or-(CH
_{2) 4} - represents a linking group M ² and Q ² are each independently a single _{bond, -CH 2 CH 2 -, -} CH (CH 3) CH 2 -, - CH 2 CH (CH 3) -, - CH (CH ₃ )
_{CH (CH 3) -, -} (CH 2) 4 -, - COO -, - OCO -, - CH 2 O-, or -O
Represents CH _2- , Ring A, Ring B and Ring C are each independently a trans-1,4-cyclohexylene group, trans-decahydronaphthalene-2,6-diyl group, trans-1,3-dioxane-
2,5-diyl group, bicyclo [2.2.2] octane-1,4-diyl group or 1,4-phenylene group optionally substituted with 1 to 2 fluorine atoms, pyridine-2,5-diyl group, Pyrimidine-2,5-diyl group, pyrazine-2,5-diyl group or pyridazine-3,6-
Represents a diyl group, m and n each independently represent 0 or 1, X ¹ , X ² and X ³ each independently represent a hydrogen atom or a fluorine atom, Z ² represents a hydrogen atom, a fluorine atom,
Trifluoromethoxy group, difluoromethoxy group or one or more fluorine atoms and / or 1 to 7 carbon atoms
Represents a saturated alkyl group having 1 to 20 carbon atoms which may be substituted by an alkoxyl group and may have a branched chain. However, this excludes the case where X ¹ , X ² and X ³ are all hydrogen atoms. A) providing a method for producing a fluorotetrahydronaphthalene derivative;

[0013]

In compounds of the above general formula (I) as described above PREFERRED EMBODIMENTS As its R ¹ include the following.

Methyl, ethyl, propyl, butyl, pentyl, hexyl, eptyl, octyl, nonyl, decyl, undecyl, dodecyl,
Tridecyl group, tetradecyl group, pentadecyl group, hexadecyl group, heptadecyl group, octadecyl group, nonadecyl group, linear saturated alkyl group of eicosyl group, 1-methylethyl group, 1-methylpropyl group, 2-methylpropyl group, 1 , 2-dimethylpropyl group, 1-methylbutyl group, 2-methylbutyl group, 3-methylbutyl group, 1,2-dimethylbutyl group, 1,3-dimethylbutyl group, 2,3-dimethylbutyl group, 1-
Methylpentyl, 2-methylpentyl, 3-methylpentyl, 4-methylpentyl, 1,2-dimethylpentyl, 1,3-dimethylpentyl, 1-methylhexyl, 2-methylpentyl
Methylhexyl, 3-methylhexyl, 4-methylhexyl, 5-methylhexyl, 1,2-dimethylhexyl, 1,3-dimethylhexyl, 1-methylheptyl, 2-
Methylheptyl group, 3-methylheptyl group, 4-methylheptyl group, 5-methylheptyl group, 6-methylheptyl group, 1,
2-dimethylheptyl group, 1,3-dimethylheptyl group, 1-methyloctyl group, 2-methyloctyl group, 3-methyloctyl group, 4-methyloctyl group, 5-methyloctyl group, 6-methyloctyl group, 7-methyloctyl, 1,2-dimethyloctyl, 1,3-dimethyloctyl, 1-methylnonyl, 2-methylnonyl, 3-methylnonyl, 4-methylnonyl, 5-methylnonyl, 6-methylnonyl Group, 7-methylnonyl group, branched saturated alkyl group such as 8-methylnonyl group, vinyl group, trans-1-propenyl group, 2-propenyl group, trans-1-butenyl group, trans-2-butenyl group, cis- 2-butenyl group, 3-butenyl group, trans-1-pentenyl group, trans-2-pentenyl group, cis-2-pentenyl group, trans-3-pentenyl group, 4-pentenyl group,
Trans-1-hexenyl group, trans-2-hexenyl group,
Cis-2-hexenyl group, trans-3-hexenyl group, trans-4-hexenyl group, cis-4-hexenyl group, 5-hexenyl group, trans-1-heptenyl group, trans-2-heptenyl group, cis-2 -Heptenyl group, trans-3-heptenyl group, trans-4-heptenyl group, cis-4-heptenyl group,
Trans-5-heptenyl group, 6-heptenyl group, trans-
1-octenyl group, trans-2-octenyl group, cis-2-octenyl group, trans-3-octenyl group, trans-4-octenyl group, cis-4-octenyl group, trans-5-octenyl group, trans-6 -Octenyl group, 7-octenyl group,
Trans-1-nonenyl group, 8-nonenyl group, trans-1-decenyl group, 9-decenyl group, ethynyl group, 1-propynyl group, 2-propynyl group, 1-butynyl group, 2-butynyl group, 3-
Butynyl group, 1-pentenyl group, 2-pentenyl group, 3-pentenyl group, 4-pentenyl group, 1-hexynyl group, 2-hexynyl group, 3-hexynyl group, 4-hexynyl group, 5-hexynyl group, 1- Heptynyl group, 2-heptynyl group, 3-heptynyl group, 4-heptynyl group, 5-heptynyl group, 6-heptynyl group, 1-octynyl group, 2-octynyl group, 3-octynyl group, 4-octynyl group, 5- Octynyl group, 6-octynyl group, 7-octynyl group, 1-noninyl group, 8-noninyl group, 1-
Decynyl group, unsaturated alkyl group such as 9-decynyl group, fluoromethyl group, difluoromethyl group, trifluoromethyl group, 2-fluoroethyl group, 2,2-difluoroethyl group,
2,2,2-trifluoroethyl group, 1,1,2,2,2-pentafluoroethyl group, 3-fluoropropyl group, 2-fluoropropyl group, 1-fluoropropyl group, 3,3-difluoropropyl Group, 3,3,3-trifluoropropyl group, 2,2,3,3-tetrafluoropropyl group, 2,2,3,3,3-pentafluoropropyl group, 1,1,2,2,3 , 3,3-heptafluoropropyl group, 4-fluorobutyl group, 3-fluorobutyl group, 2-fluorobutyl group, 1-fluorobutyl group, 4,4-difluorobutyl group, 4,
4,4-trifluorobutyl group, 3,3,4,4-tetrafluorobutyl group, 3,3,4,4,4-pentafluorobutyl group, 2,2,3,3,
4,4,4-heptafluorobutyl group, 5-fluoropentyl group, 4-fluoropentyl group, 3-fluoropentyl group, 2-
Fluoropentyl group, 1-fluoropentyl group, 5,5-difluoropentyl group, 5,5,5-trifluoropentyl group, 4,
4,5,5-tetrafluoropentyl group, 4,4,5,5,5-pentafluoropentyl group, 3,3,4,4,5,5,5-heptafluoropentyl group, 6-fluorohexyl group , 5-fluorohexyl, 4-fluorohexyl, 3-fluorohexyl, 2-
Fluorohexyl group, 1-fluorohexyl group, 6,6-difluorohexyl group, 6,6,6-trifluorohexyl group, 5,
5,6,6,6-pentafluorohexyl group, 4,4,5,5,6,6,6-heptafluorohexyl group, 7-fluoroheptyl group, 6-fluoroheptyl group, 5-fluoroheptyl group, 4-fluoroheptyl group, 3-fluoroheptyl group, 2-fluoroheptyl group, 1-fluoroheptyl group, 7,7-difluoroheptyl group, 7,7,7-trifluoroheptyl group, 6,6,7,7 -Tetrafluoroheptyl group, 6,6,7,7,7-pentafluoroheptyl group, 5,5,6,6,7,7,7-heptafluoroheptyl group, 8-fluorooctyl group, 7-fluorooctyl Group, 6-fluorooctyl group, 5-fluorooctyl group, 4-fluorooctyl group, 3-fluorooctyl group, 2-fluorooctyl group, 1-
Fluorooctyl group, 8,8-difluorooctyl group, 8,8,
8-trifluorooctyl group, 7,7,8,8-tetrafluorooctyl group, 7,7,8,8,8-pentafluorooctyl group, 6,6,
Fluorine-substituted alkyl group such as 7,7,8,8,8-heptafluorooctyl group, 2,2-difluoroethenyl group, (E) -1,2-difluoroethenyl group, (Z) -1,2 -Difluoroethenyl group, 3,3-
Difluoro-2-propenyl group, (E) -2,3-difluoro-2-propenyl group, (Z) -2,3-difluoro-2-propenyl group, 4,4
-Difluoro-3-butenyl group, (E) -3,4-difluoro-3-butenyl group, (Z) -3,4-difluoro-3-butenyl group, 5,5-difluoro-4-pentenyl group, E) -4,5-difluoro-4-pentenyl group, (Z) -4,5-difluoro-4-pentenyl group, 6,6-
Difluoro-5-hexenyl group, (E) -5,6-difluoro-5-hexenyl group, (Z) -5,6-difluoro-5-hexenyl group, (E)
-1,2-difluoro-1-propenyl group, (E) -1,2-difluoro
-1-butenyl group, (E) -1,2-difluoro-1-pentenyl group,
(E) -1,2-difluoro-1-hexenyl group, (Z) -1-fluoro-
1-propenyl group, (Z) -1-fluoro-1-butenyl group, (Z) -1
-Fluoro-1-pentenyl group, (Z) -1-fluoro-1-hexenyl group, (Z) -2-fluoro-1-propenyl group, (Z) -2-fluoro-1-butenyl group, (Z) -2-fluoro-1-pentenyl group,
(Z) -2-fluoro-1-hexenyl group, (E) -2,3-difluoro
-2-butenyl group, (E) -2,3-difluoro-2-pentenyl group,
(E) -2,3-difluoro-2-hexenyl group, (Z) -2-fluoro
-2-butenyl group, (Z) -2-fluoro-2-pentenyl group, (Z)-
Fluorine such as 2-fluoro-2-hexenyl group, (Z) -3-fluoro-2-butenyl group, (Z) -3-fluoro-2-pentenyl group, (Z) -3-fluoro-2-hexenyl group A substituted unsaturated alkyl group,
Methoxymethyl group, ethoxymethyl group, propoxymethyl group, butoxymethyl group, pentyloxymethyl group, hexyloxymethyl group, heptyloxymethyl group, 1-methoxyethyl group, 1-ethoxyethyl group, 1-propoxyethyl group, 1 -Butoxyethyl group, 1-pentyloxyethyl group, 1-hexyloxyethyl group, 1-heptyloxyethyl group, 2-methoxyethyl group, 2-ethoxyethyl group, 2-propoxyethyl group, 2-butoxyethyl group, 2-pentyloxyethyl group, 2-hexyloxyethyl group, 2-heptyloxyethyl group, 1-methoxypropyl group, 1-ethoxypropyl group, 1-propoxypropyl group, 1-butoxypropyl group, 1-pentyloxypropyl Group, 1-hexyloxypropyl group, 1-heptyloxypropyl group, 2-methoxypropyl group, 2-ethoxypropyl group , 2-propoxypropyl, 2-butoxypropyl, 2-pentyloxypropyl, 2-hexyloxypropyl, 2-heptyloxypropyl, 3-methoxypropyl, 3-ethoxypropyl, 3-propoxypropyl Group, 3-butoxypropyl group, 3-pentyloxypropyl group, 3-hexyloxypropyl group, 3-heptyloxypropyl group, 4-methoxybutyl group, 4-ethoxybutyl group, 4-propoxybutyl group,
4-butoxybutyl group, 4-pentyloxybutyl group, 4-hexyloxybutyl group, 4-heptyloxybutyl group, 5-
Methoxypentyl group, 5-ethoxypentyl group, 5-propoxypentyl group, 5-butoxypentyl group, 5-pentyloxypentyl group, 5-hexyloxypentyl group, 5-heptyloxypentyl group, 6-methoxyhexyl group, 6 And alkoxy-substituted alkyl groups such as -ethoxyhexyl group, 6-propoxyhexyl group, 6-butoxyhexyl group, 6-pentyloxyhexyl group, 6-hexyloxyhexyl group and 6-heptyloxyhexyl group. When the compound contains an asymmetric carbon, it may be optically active or racemic.

[0015] In the compounds of the general formula (II), examples of the R ² include the following. Methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl , Octadecyl group, nonadecyl group, linear saturated alkyl group of eicosyl group, 1-methylethyl group, 1-methylpropyl group, 2-methylpropyl group, 1,2-dimethylpropyl group, 1-methylbutyl group, 2- Methylbutyl group, 3-methylbutyl group, 1,2-dimethylbutyl group, 1,3-dimethylbutyl group, 2,3-dimethylbutyl group, 1-methylpentyl group, 2-methylpentyl group, 3-methylpentyl group, 4-methylpentyl, 1,2-dimethylpentyl, 1,3-dimethylpentyl, 1-methylhexyl, 2-methylhexyl, 3-methylhexyl, 4-methylhexyl 5-methylhexyl group, 1,2-dimethylhexyl group, 1,3-dimethylhexyl group, 1-methylheptyl group, 2-methylheptyl group, 3-methylheptyl group, 4-methylheptyl group, 5 -Methylheptyl group, 6-methylheptyl group, 1,2-dimethylheptyl group, 1,
3-dimethylheptyl group, 1-methyloctyl group, 2-methyloctyl group, 3-methyloctyl group, 4-methyloctyl group, 5-methyloctyl group, 6-methyloctyl group, 7-methyloctyl group, 1, 2-dimethyloctyl group, 1,3-dimethyloctyl group, 1-methylnonyl group, 2-methylnonyl group, 3-
Methylnonyl group, 4-methylnonyl group, 5-methylnonyl group, 6-methylnonyl group, 7-methylnonyl group, branched saturated alkyl groups such as 8-methylnonyl group, fluoromethyl group,
Difluoromethyl group, trifluoromethyl group, 2-fluoroethyl group, 2,2-difluoroethyl group, 2,2,2-trifluoroethyl group, 1,1,2,2,2-pentafluoroethyl group, 3 -
Fluoropropyl group, 2-fluoropropyl group, 1-fluoropropyl group, 3,3-difluoropropyl group, 3,3,3-trifluoropropyl group, 2,2,3,3-tetrafluoropropyl group, 2, 2,3,3,3-pentafluoropropyl group, 1,1,2,2,3,
3,3-heptafluoropropyl group, 4-fluorobutyl group,
3-fluorobutyl group, 2-fluorobutyl group, 1-fluorobutyl group, 4,4-difluorobutyl group, 4,4,4-trifluorobutyl group, 3,3,4,4-tetrafluorobutyl group, 3,3,4,
4,4-pentafluorobutyl group, 2,2,3,3,4,4,4-heptafluorobutyl group, 5-fluoropentyl group, 4-fluoropentyl group, 3-fluoropentyl group, 2-fluoropentyl Group, 1-fluoropentyl group, 5,5-difluoropentyl group, 5,5,5-trifluoropentyl group, 4,4,5,5-tetrafluoropentyl group, 4,4,5,5,5- Pentafluoropentyl group, 3,3,4,4,5,5,5-heptafluoropentyl group, 6-fluorohexyl group, 5-fluorohexyl group, 4-fluorohexyl group, 3-fluorohexyl group, 2- Fluorohexyl group, 1-fluorohexyl group, 6,6-difluorohexyl group, 6,6,6-trifluorohexyl group, 5,5,6,6,6-pentafluorohexyl group, 4,4,5, 5,6,6,6-heptafluorohexyl group, 7-fluoroheptyl group, 6-fluoroheptyl group, 5-fluoroheptyl group, 4-fluoroheptyl group, 3-
Fluoroheptyl group, 2-fluoroheptyl group, 1-fluoroheptyl group, 7,7-difluoroheptyl group, 7,7,7-trifluoroheptyl group, 6,6,7,7-tetrafluoroheptyl group, 6, 6,7,7,7-pentafluoroheptyl group, 5,5,6,6,7,
7,7-heptafluoroheptyl group, 8-fluorooctyl group, 7-fluorooctyl group, 6-fluorooctyl group, 5-
Fluorooctyl group, 4-fluorooctyl group, 3-fluorooctyl group, 2-fluorooctyl group, 1-fluorooctyl group, 8,8-difluorooctyl group, 8,8,8-trifluorooctyl group, 7,7 , 8,8-tetrafluorooctyl group, 7,
7,8,8,8-pentafluorooctyl group, fluorine-substituted alkyl group such as 6,6,7,7,8,8,8-heptafluorooctyl group, methoxymethyl group, ethoxymethyl group, propoxymethyl group, Butoxymethyl group, pentyloxymethyl group, hexyloxymethyl group, heptyloxymethyl group, 1-methoxyethyl group, 1-ethoxyethyl group, 1-propoxyethyl group, 1-butoxyethyl group, 1-pentyloxyethyl group, 1-hexyloxyethyl group, 1-heptyloxyethyl group, 2-methoxyethyl group, 2-ethoxyethyl group, 2-propoxyethyl group, 2-butoxyethyl group, 2-pentyloxyethyl group, 2-hexyloxyethyl Group, 2-heptyloxyethyl group, 1-methoxypropyl group, 1-ethoxypropyl group, 1-propoxypropyl group, 1-butoxypropyl group, 1-pentyloxypropyl group, Siloxypropyl group, 1-heptyloxypropyl group, 2-methoxypropyl group, 2-ethoxypropyl group, 2-propoxypropyl group, 2-butoxypropyl group, 2-pentyloxypropyl group, 2-hexyloxypropyl group, 2-heptyloxypropyl, 3-methoxypropyl, 3-ethoxypropyl, 3-propoxypropyl, 3-butoxypropyl, 3-pentyloxypropyl, 3-hexyloxypropyl, 3-heptyloxypropyl Group, 4-methoxybutyl group, 4-ethoxybutyl group, 4-propoxybutyl group,
4-butoxybutyl group, 4-pentyloxybutyl group, 4-hexyloxybutyl group, 4-heptyloxybutyl group, 5-
Methoxypentyl group, 5-ethoxypentyl group, 5-propoxypentyl group, 5-butoxypentyl group, 5-pentyloxypentyl group, 5-hexyloxypentyl group, 5-heptyloxypentyl group, 6-methoxyhexyl group, 6 And alkoxy-substituted alkyl groups such as -ethoxyhexyl group, 6-propoxyhexyl group, 6-butoxyhexyl group, 6-pentyloxyhexyl group, 6-hexyloxyhexyl group and 6-heptyloxyhexyl group. When the compound contains an asymmetric carbon, it may be optically active or racemic.

Z ¹ is a hydrogen atom, a fluorine atom, a trifluoromethoxy group, a difluoromethoxy group, or the aforementioned R ¹
The groups described are mentioned.

Z ² represents a hydrogen atom, a fluorine atom, a trifluoromethoxy group, a difluoromethoxy group, or the above-mentioned R ²
The groups described are mentioned.

Ring A, ring B and ring C are trans-1,4-cyclohexylene, trans-decahydronaphthalene-2,6-diyl, trans-1,3-dioxane-2,5-diyl, Bicyclo [2.2.2] octane-1,4-diyl group and 1,4-phenylene group optionally substituted with one or two fluorine atoms,
Pyridine-2,5-diyl, pyrimidine-2,5-diyl, pyrazine-2,5-diyl and pyridazine-3,6-diyl. Among them, ring A is trans-1,4-cyclohexylene group, trans-decahydronaphthalene-2,6-diyl group, trans-1,3-dioxane-2,5-diyl group, bicyclo
[2.2.2] An octane-1,4-diyl group and a 1,4-phenylene group optionally substituted with one or two fluorine atoms are preferred, and a trans-1,4-cyclohexylene group, trans-decahydro Naphthalene-2,6-diyl group, trans-1,3-dioxane-2,5-diyl group or bicyclo [2.2.2] octane-
A 1,4-diyl group is particularly preferred. Ring C is preferably a 1,4-phenylene group which may be substituted with one or two fluorine atoms, and 1,4-phenyl group substituted with one or two fluorine atoms.
A phenylene group is particularly preferred.

M and n represent 0 or 1, and it is preferred that n is 0.

Linking group L¹Is a single bond, -CH_TwoCH_Two-, -CH = CH-,-
CH (CH_Three) CH_Two-, -CH_TwoCH (CH_Three)-, -CH (CH_Three) CH (CH_Three)-、-C≡C
-Or- (CH_Two)_Four-Represents a linking group M¹And Q¹Is a single bond,-
CH_TwoCH_Two-, -CH = CH-, -CH (CH_Three) CH_Two-, -CH_TwoCH (CH_Three)-, -CH
(CH_Three) CH (CH_Three)-, -C≡C-,-(CH _Two)_Four-, -COO-, -OCO-, -CH
_TwoO- or -OCH_Two-Represents a linking group L¹Is a single bond, -CH_TwoCH _Two
-, -CH (CH_Three) CH_Two-, -CH_TwoCH (CH_Three)-, -CH (CH_Three) CH (CH_Three)-,
Or-(CH_Two)_Four-Represents a linking group M¹And Q¹Is a single bond, -C
H_TwoCH_Two-, -CH (CH_Three) CH_Two-, -CH_TwoCH (CH_Three)-, -CH (CH_Three) CH (C
H_Three)-,-(CH_Two)_Four-, -COO-, -OCO-, -CH_TwoO- or -OCH_Two-
Represents a single bond and -CH_TwoCH_Two-Is preferred, and the single bond is
Particularly preferred.

As the hydrogenation reduction catalyst, Rh, Ru, Pt, P
d, Ir or Os metal or a metal compound thereof. These metals and metal compounds may be used alone or in combination of two or more.

For example, specific examples of Pd metal and its compounds include palladium carbon, palladium powder, palladium oxide, palladium chloride, palladium bromide, palladium iodide, tetraamminepalladium chloride, tetraamminepalladium nitrate, and tetraamminepalladium acetate. Such as palladium salts or tetrakis (triphenylphosphine) palladium, bis (acetylacetonate)
Palladium complexes such as palladium can be mentioned.

In place of Pd, Rh, Ru, Pt, R
The same applies to the metals e, Ir, and Os and / or their metal compounds.

These metals and metal compounds are 1
Species may be used alone or in combination of two or more. Further, silica gel, alumina or the like may be added or supported on these. Among them, a metal of Pd or a metal compound thereof is preferable.

This reaction is carried out under a hydrogen atmosphere from a hydrogen atmosphere at 200 atm.
9.6 MPa), but preferably from hydrogen atmosphere to 100 atm (9.8 MPa) of hydrogen, and from the hydrogen atmosphere to 40 atm (3.9 MPa) from hydrogen to simplify the use of the reaction vessel.
Particularly preferred is below.

Various solvents can be used in this reaction. As the reaction solvent, methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, alcohols such as 2-methyl-1-propanol, organic acids such as acetic acid, diethyl ether, methyl-t- Butyl ether, ethers such as tetrahydrofuran, ethyl acetate, methyl acetate, esters such as butyl acetate, pentane, hexane, heptane, saturated hydrocarbons such as octane, benzenes such as benzene, toluene, xylene, N,
Amides such as N-dimethylformamide and N, N-dimethylacetamide can be used alone or as a mixture, but alcohols, organic acids and mixed solvents containing them are preferred.

This reaction can be carried out at a temperature from the freezing point of the solvent to 300 ° C., preferably from 0 ° C. to 200 ° C.

Compounds of the general formula (I) are described in the literature (JP-A-2000-63).
It can be easily synthesized by the method described in 305).

[0029]

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

Example 1 5-Fluoro-2-propyl-6-
Synthesis of (3,4,5-trifluorophenyl) -1,2,3,4-tetrahydronaphthalene (1)

Embedded image In a 100 ml glass autoclave, 1-fluoro-6-propyl-2- (3,4,5-trifluorophenyl) naphthalene (0.5
g), 5% palladium on carbon (containing 50% water) (0.1 g) and ethanol (10 ml), and 5 atm of hydrogen (0.49 MPa)
The mixture was stirred at 80 ° C for 14 hours. When the reaction solution was confirmed by gas chromatography, 1-fluoro-6-propyl-2-
(3,4,5-trifluorophenyl) naphthalene disappears,
Fluoro-2-propyl-6- (3,4,5-trifluorophenyl)
It contained -1,2,3,4-tetrahydronaphthalene with a selectivity of 91%.

Example 2 5-Fluoro-2-propyl-6-
Synthesis of (3,4,5-trifluorophenyl) -1,2,3,4-tetrahydronaphthalene (2) 1-fluoro-6-propyl-2- (3,4,5 -Trifluorophenyl) naphthalene (10
g), 5% palladium on carbon (50% water-containing) (1 g) and ethanol (100 ml), and the mixture was added under 5 atmospheres of hydrogen (0.49 MPa).
Stirred at 80 ° C. for 14 hours. The reaction solution was filtered through celite, and the filtrate was concentrated. The residue was purified by silica gel chromatography (hexane) to give 5-fluoro-2-propyl-6-
(3,4,5-trifluorophenyl) -1,2,3,4-tetrahydronaphthalene (9.5 g, purity 95%) was obtained. Further recrystallization from ethanol gave 5-fluoro-2-propyl-6- (3,4,5-trifluorophenyl) -1,2,3,4-tetrahydronaphthalene (6 g, purity> 99%). Was.

Example 3 5-Fluoro-2- (4-propyl-
Synthesis of (trans-cyclohexyl) -6- (3,4,5-trifluorophenyl) -1,2,3,4-tetrahydronaphthalene

Embedded image

Under the same conditions as in Example 1, 1-fluoro-6-
1-fluoro-6- (4-propyl-trans-cyclohexyl) -2- (3,4,5-trifluorophenyl) naphthalene is used instead of propyl-2- (3,4,5-trifluorophenyl) naphthalene. Using, 5-fluoro-2- (4-propyl-trans-cyclohexyl) -6- (3,4,5-trifluorophenyl) -1,2,3,4-
Tetrahydronaphthalene was synthesized.

[0034]

According to the present invention, it has been difficult to obtain until now,
A fluorotetrahydronaphthalene derivative whose production method is complicated can be industrially easily and inexpensively produced using an easily available fluoronaphthalene derivative. This fluorotetrahydronaphthalene derivative is extremely useful for liquid crystal displays that require low-voltage driving and high-speed response.

Claims (10)

[Claims] 1. A compound of the general formula (I)(Where R¹Is one or more fluorine atoms and / or carbon
Substituted by an alkoxyl group having 1 to 7 atoms
Or a saturated or unsaturated carbon which may contain a branched chain
Represents an alkyl group of Formulas 1 to 20, and a connecting group L¹Is a single bond, -CH_Two
CH_Two-, -CH = CH-, -CH (CH_Three) CH_Two-, -CH_TwoCH (CH_Three)-, -CH (C
H_Three) CH (CH_Three)-, -C≡C- or-(CH_Two)_Four-Represents a linking group M¹
And Q¹Are each independently a single bond, -CH_TwoCH_Two-, -CH = CH
-, -CH (CH_Three) CH_Two-, -CH_TwoCH (CH_Three)-, -CH (CH_Three) CH (CH_Three)-,-
C≡C-,-(CH_Two)_Four-, -COO-, -OCO-, -CH _TwoO- or -OCH_Two
And ring A, ring B and ring C are each independently trans
1,4-cyclohexylene group, trans-decahydronaph
Taren-2,6-diyl group, trans-1,3-dioxane-2,5-
Diyl group, bicyclo [2.2.2] octane-1,4-diyl group or
Is 1,4-phenylene which may be substituted by 1 to 2 fluorine atoms
Group, pyridine-2,5-diyl group, pyrimidine-2,5-diyl
Group, pyrazine-2,5-diyl group or pyridazine-3,6-di
And m and n are each independently 0 or 1
And X¹, X^TwoAnd X^ThreeAre each independently a hydrogen atom
Or a fluorine atom, Z¹Represents a hydrogen atom, a fluorine atom,
Trifluoromethoxy group, difluoromethoxy group or 1
Not less than 1 fluorine atom and / or 1 to 7 carbon atoms
A branched chain which may be substituted by an alkoxyl group;
A saturated or unsaturated C 1-20 alkyl which may contain
Represents a kill group. Where X¹, X^TwoAnd X^ThreeAre all hydrogen sources
Except when it is a child. ) Fluoronaphthalene represented by
A compound represented by the general formula (I)
I)(Where R^TwoIs one or more fluorine atoms and / or carbon
Substituted by an alkoxyl group having 1 to 7 atoms
Or a saturated C 1-20 carbon atom which may contain a branched chain.
Represents a alkyl group and a linking group L^TwoIs a single bond, -CH_TwoCH_Two-, -CH (CH
_Three) CH_Two-, -CH_TwoCH (CH_Three)-, -CH (CH_Three) CH (CH_Three)-Or-(CH
_Two)_Four-Represents a linking group M^TwoAnd Q^TwoAre independently connected
If -CH_TwoCH_Two-, -CH (CH_Three) CH_Two-, -CH_TwoCH (CH_Three)-, -CH (CH_Three)
CH (CH_Three)-,-(CH_Two)_Four-, -COO-, -OCO-, -CH_TwoO- or -O
CH_TwoWherein ring A, ring B and ring C are each independently
Lance-1,4-cyclohexylene group, trans-decahydro
Naphthalene-2,6-diyl group, trans-1,3-dioxane-
2,5-diyl group, bicyclo [2.2.2] octane-1,4-diyl group
Or 1,4-phenylene which may be substituted by 1 to 2 fluorine atoms
Len group, pyridine-2,5-diyl group, pyrimidine-2,5-diyl
Group, pyrazine-2,5-diyl group or pyridazine-3,6-
Represents a diyl group, m and n are each independently 0 or
Represents 1 and X¹, X^TwoAnd X^ThreeAre each independently a hydrogen atom
Or a fluorine atom, Z^TwoIs a hydrogen atom, a fluorine atom,
Trifluoromethoxy group, difluoromethoxy group or
At least one fluorine atom and / or 1 to 7 carbon atoms
May be substituted by an alkoxyl group of
Represents a saturated alkyl group having 1 to 20 carbon atoms which may contain a chain.
You. Where X¹, X^TwoAnd X^ThreeAre all hydrogen atoms
Excludes ) Of fluorotetrahydronaphthalene derivative
Production method. 2. The method according to claim 1, wherein the reduction is Rh, Ru, Pt, Pd, Re, Ir or Os.
2. The method according to claim 1, wherein at least one kind of hydrogenation reduction catalyst selected from the above metals or metal compounds thereof is used. 3. The method according to claim 1, wherein the reduction uses a metal of Pd or a metal compound thereof. 4. The method according to claim 1, wherein the reduction is carried out under a condition from a hydrogen atmosphere to 40 atm of hydrogen. 5. The method according to claim 1, wherein the reduction is carried out at room temperature to 200 ° C. 6. In the general formulas (I) and (II), n is 0
The method according to any one of claims 1 to 5, wherein 7. In the general formulas (I) and (II), ring A is trans-1,4-cyclohexylene, trans-decahydronaphthalene-2,6-diyl, trans-1,3-dioxane
A 2,4-diyl group, a bicyclo [2.2.2] octane-1,4-diyl group and a 1,4-phenylene group which may be substituted by one or two fluorine atoms. 7. The production method according to any one of 6. 8. In the general formulas (I) and (II), ring A is trans-1,4-cyclohexylene, trans-decahydronaphthalene-2,6-diyl, trans-1,3-dioxane
The process according to any one of claims 1 to 6, which is a -2,5-diyl group or a bicyclo [2.2.2] octane-1,4-diyl group. 9. The production method according to claim 1, wherein Q ¹ and Q ² in the general formulas (I) and (II) are a single bond. 10. The ring C in the general formulas (I) and (II)
May be substituted with one or two fluorine atoms
The method according to any one of claims 1 to 9, which is a phenylene group.