JP2000239214A - Decahydronaphthalene derivative and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a new compound capable of inexpensively and readily producing a phenyldecahydronaphthalen-one derivative being an intermediate for producing a phenyl decahydronaphthalene derivative useful as a material for an electrooptical liquid crystal display. SOLUTION: This compound is shown by formula I (Z1 and Z2 are each a 1-6C alkyl or Z1 and Z2 are bonded to form a 1-7C alkylene) such as decahydronaphthalen-2,6-dione monoethylene acetal. The compound of formula I is obtained, for example, by reacting a cyclohexane-1,4-dione monoacetal of formula II with a secondary amine and then methyl vinyl ketone to give an octahydronaphthalene-2,6-dione monoacetal of formula III and reducing the compound. The compound of formula I is reacted with an organometallic reactant of formula IV (W is a metal to be subjected to nucleophilic addition to carbonyl or the like; Xa to Xc are each H or F; Y is H, Cl or the like), dehydrated, hydrogenated and deacetalized to give a 6- phenyldecahydronaphthalen-2-one derivative of formula V.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an intermediate for producing a phenyldecahydronaphthalene derivative useful as a material for an electro-optical liquid crystal display.

[0002]

2. Description of the Related Art Liquid crystal display devices have come to be used in various measuring instruments, such as watches and calculators, automobile panels, word processors, electronic notebooks, printers, computers, televisions, and the like. ing. As a liquid crystal display system,
Typical examples are TN (twisted nematic) type, STN (super twisted nematic) type, DS (dynamic light scattering) type, GH (guest-host) type or FLC (ferroelectric liquid crystal), etc. Multiplex drive has become more common than conventional static drive as a drive method.
Recently, the active matrix system has been put to practical use.

[0003] In accordance with these display methods and drive methods, various characteristics are required as liquid crystal materials. Above all, a wide temperature range is very important in most cases.This is because the maximum temperature of the nematic phase (T _NI ) is sufficiently high and the melting point (T _CN ) or the smectic-nematic transition temperature ( T _SN ) is sufficiently low.

Also, compatibility with other liquid crystal compounds and general-purpose liquid crystal compositions is important. If the compatibility is poor, it is necessary to mix a very large number of liquid crystal compounds in order to avoid the risk of precipitation or phase separation, and the preparation of the composition requires a great deal of time and cost. Couldn't. A sufficiently low drive voltage is also an important characteristic in many cases, and therefore, the threshold voltage (V _th ) needs to be low. In addition, high speed response is also an important characteristic, and therefore, it is required that the viscosity of the liquid crystal be as small as possible. The refractive index anisotropy (Δn) is also an important characteristic, and various values are required depending on the display method. However, a small value is required for a liquid crystal element having a large cell thickness, which is easy to manufacture. Often done.

To meet these demands, a large number of liquid crystal compounds have been synthesized so far, but not all of the problems have been solved, and liquid crystals having better properties for each of the above demands have not been solved. At present, compounds are required.

Generally, a liquid crystal compound is structurally formed from a central skeleton (core) portion and side groups (side chains and polar groups). Examples of the ring structure constituting the core portion include a 1,4-phenylene group (which may be substituted by fluorine) and a trans-1,4-cyclohexylene group, a pyridine-2,5-diyl group and a pyrimidine- Many are already known, such as a heteroaromatic ring such as a 2,5-diyl group and a saturated heterocycle such as a dioxane-trans-1,4-diyl group and a piperidine-1,4-diyl group. However, it is usually almost limited to a 1,4-phenylene group (which may be substituted by fluorine), a trans-1,4-cyclohexylene group and a small number of heteroaromatic rings, and is composed of these ring structures. The fact is that the liquid crystal compound alone cannot sufficiently meet the characteristics required for a liquid crystal composition which is becoming more advanced year by year.

It is known that the conversion of the trans-1,4-cyclohexylene group into a trans-2,6-transdecahydronaphthylene group improves liquid crystallinity. Moreover, since the trans-2,6-transdecahydronaphthylene group is a saturated ring containing no hetero atom such as an oxygen atom or a nitrogen atom, excellent stability can be expected.
However, there have been few examples of trans-2,6-transdecahydronaphthalene derivatives reported so far, and their properties were hardly known.

Recently, we have found that 2- (3,5-difluoro-4-
(Cyanophenyl) transdecahydronaphthalene derivative (A)

[0009]

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Or 2- (3,4,5-trifluorophenyl)
Transdecahydronaphthalene derivative (B)

[0011]

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And other novel trans-decahydronaphthalene derivatives which exhibit excellent liquid crystallinity and have a threshold voltage
It has excellent effects such as reduction of (V _th ), reduction of refractive index anisotropy (Δn), expansion of nematic phase temperature range, and excellent compatibility with other liquid crystal compounds and general-purpose liquid crystal compositions. And reported that it is useful as a liquid crystal material.

On the other hand, the side groups in the liquid crystal compound are usually composed of a chain group and a polar group. In the case of a so-called p-type liquid crystal having a positive dielectric anisotropy (Δε), one is a chain group and the other is a chain group. In the case of a so-called n-type liquid crystal which is a polar group and has a negative Δε, both are often chain groups. Alkyl groups are usually used as the chain group.However, by replacing this alkyl group with an alkenyl group, the liquid crystal property is improved, the viscosity is reduced, and the sharpness in the voltage (V) -transmittance (T) curve is improved. It is known that there is an effect on improvement and the like. From these viewpoints, the present inventors (C)

[0014]

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We have developed 6- (alkenyl) -2-phenyltransdecahydronaphthalene derivatives and reported that they show excellent properties.

By the way, 6- (alkenyl) -2-phenyltransdecahydronaphthalene derivatives such as (C) are obtained by using a 6-phenyltransdecahydronaphthalen-2-one derivative as an intermediate and its keto (carbonyl) group. To an alkenyl group. This 6-phenyltransdecahydronaphthalen-2-one derivative is currently produced by reacting an enamine derived from the corresponding 4-phenylcyclohexanone derivative with methyl vinyl ketone.
A 6-phenyloctahydronaphthalen-2-one derivative is obtained by subsequent reduction. However, since the starting material, 4-phenylcyclohexanone derivative, is not inexpensive and the yield of conversion of the cyclohexanone ring to the transdecahydronaphthalene ring is not sufficiently high, it is not advantageous in terms of production cost. I could not say. Therefore, there is a demand for a cheaper and easier method for producing a 6-phenyltransdecahydronaphthalen-2-one derivative which is important as an intermediate for producing a 2-phenyltransdecahydronaphthalene-based liquid crystal.

[0017]

The problem to be solved by the present invention is to provide a novel compound, transdecahydronaphthalene-2,6-dionemonoacetal and a process for producing the same. Is an intermediate for the production of phenyldecahydronaphthalene derivatives etc.
An object of the present invention is to provide an advantageous method for producing a 6-phenyldecahydronaphthalen-2-one derivative.

[0018]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides: 1. The general formula (I)

[0019]

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(Wherein Z ¹ and Z ² are each independently an alkyl group having 1 to 6 carbon atoms in the main chain or Z ¹ and Z ² are linked to each other to form an alkylene group having 1 to 7 carbon atoms in the main chain. Represents decahydronaphthalene-2,6-dionemonoaceta-
Le. 2. The decahydronaphthalene-2,6-dione monoacetal according to the above 1, wherein in formula (I), Z ¹ and Z ² are linked to each other to represent an alkylene group having 1 to 7 carbon atoms in the main chain. 3. The decahydronaphthalene-2,6-dione monoacetal according to the above 1, wherein in the general formula (I), Z ¹ and Z ² are connected to each other to represent an ethylene group or a 1,3-propylene group. 4.General formula (II)

[0021]

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Wherein Z ¹ and Z ² are each independently an alkyl group having 1 to 6 carbon atoms in the main chain or Z ¹ and Z ² are linked to each other to form an alkylene group having 1 to 7 carbon atoms in the main chain. Represents cyclohexane-1,4-dionemonoacetal represented by 2
General amine (III) by reacting with enamine with a secondary amine and then reacting with methyl vinyl ketone

[0023]

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Wherein Z ¹ and Z ² are each independently an alkyl group having 1 to 6 carbon atoms in the main chain or Z ¹ and Z ² are linked to each other to form an alkylene group having 1 to 7 carbon atoms in the main chain. Wherein octahydronaphthalene-2,6-dionemonoacetal represented by the general formula (I) is obtained by reducing and hydrogenating the octahydronaphthalene-2,6-dionemonoacetal. -A method for producing 2,6-dione monoacetal. 5. The production method according to the above item 4, wherein the reduction is performed using an alkali metal in ammonia or an amine solvent. 6.Decahydronaphthalene-2,6-dione

[0025]

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Wherein decahydronaphthalene represented by the general formula (I) as described in 1 above is converted to a monoacetal.
-A method for producing 2,6-dione monoacetal. 7.Decahydronaphthalene-2,6-diol

[0027]

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7. The process according to the above item 6, wherein oxidizing is carried out to obtain decahydronaphthalene-2,6-dione. 8.Decahydronaphthalene-2,6-diol is converted to naphthalene-
2,6-dione

[0029]

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8. The production method according to the above 7, wherein the production method is obtained by reducing hydrogenation. 9.General formula (IV)

[0031]

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(Wherein, Z ¹ and Z ² are each independently an alkyl group having 1 to 6 carbon atoms in the main chain or Z ¹ and Z ² are linked to each other to form an alkylene group having 1 to 7 carbon atoms in the main chain. Wherein Z ³ and Z ⁴ are each independently an alkyl group having 1 to 6 main chain carbon atoms or Z ³ and Z ⁴ are connected to each other to have 1 to 7 main chain carbon atoms.
Wherein Z ^{1 to} Z ⁴ may be the same or different. Decahydronaphthalene-2,6-dione monoacetal represented by the general formula (I) according to 1 above, wherein decahydronaphthalene-2,6-dionediacetal is partially hydrolyzed. Manufacturing method. 10.6-Hydroxydecahydronaphthalen-2-one

[0033]

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A process for producing decahydronaphthalene-2,6-dionemonoacetal represented by the general formula (I) as described in 1 above, wherein the hydroxyl group is oxidized after acetalization. 11. The method according to the above item 10, wherein 6-hydroxydecahydronaphthalen-2-one is obtained by reducing and hydrogenating naphthalene-2,6-diol. 12.Decahydronaphthalene-2,6-dione monoacetal according to the above 1 has the general formula (V)

[0035]

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(Wherein W represents a metal or a metal-containing group capable of nucleophilic addition to a carbonyl group, X ^a , X ^b and X ^c each independently represent a hydrogen atom or a fluorine atom; Is a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, a fluorine atom or an alkyl or alkoxyl group having 1 to 12 carbon atoms which may be substituted by an alkoxyl group having 1 to 7 carbon atoms, a protected cyano group , Represents a protected hydroxyl group or a protected carboxyl group), and after dehydration, followed by hydrogenation and deacetalization, a general formula ( VI)

[0037]

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(Wherein X ^a , X ^b and X ^c each independently represent a hydrogen atom or a fluorine atom, and Y represents a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, a fluorine atom or a carbon atom having 1 to 7 represents an alkyl or alkoxyl group having 1 to 12 carbon atoms which may be substituted by a 7 alkoxyl group, a protected cyano group, a protected hydroxyl group or a protected carboxyl group. A method for producing a phenyldecahydronaphthalen-2-one derivative. Was found as a means for solving the above-mentioned problem.

[0039]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An example of the present invention will be described below.

The present invention relates to a compound of the formula (I)

[0041]

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There is provided a decahydronaphthalene-2,6-dione monoacetal represented by the formula: In the formula, Z ¹ and Z ² are each independently an alkyl group having 1 to 6 carbon atoms in the main chain or Z ¹
And Z ² are connected to each other to represent an alkylene group having 1 to 7 carbon atoms in the main chain, but these are an alkyl group having 1 to 7 carbon atoms,
It may be substituted by an aryl group, an aralkyl group or an alkoxyl group, preferably an alkylene group having 1 to 7 carbon atoms in the main chain, more preferably an ethylene group or a 1,3-propylene group.

The compound of the general formula (I) can be produced by the following production routes (a) to (d), and the present invention also provides a method for producing them.

A) General formula (II)

[0045]

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(Wherein Z has the same meaning as in general formula (I)), and cyclohexane-1,4-dionemonoacetal is converted to an enamine with a secondary amine, and then reacted with methyl vinyl ketone. By the general formula (III)

[0047]

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(Wherein Z has the same meaning as in formula (I)) to give octahydronaphthalene-2,6-dionemonoacetal. This is reduced with an alkali metal in an ammonia or amine solvent to give decahydronaphthalene-2,6- represented by the general formula (I).
Dione monoacetal can be obtained.

The raw material (II) is a general-purpose compound particularly as an intermediate for producing an alkenyl liquid crystal compound, and a part of which is commercially available.

As the secondary amine for forming enamine, cyclic amines such as pyrrolidine, piperidine, pipecoline and morpholine, and dialkylamines such as diethylamine, dipropylamine and dibutylamine can be used. And morpholine are preferred.

As the alkyl metal for reduction, lithium or sodium is preferable, but in some cases, an alkaline earth metal such as calcium can be used.

As a solvent for the reduction, liquefied ammonia, lower amines such as methylamine, ethylamine and dimethylamine, and polyamines such as ethylenediamine can be used. These are usually preferably used in combination with alcohols (preferably t-butanol) as a hydrogen source, and it is also possible to use a hydrocarbon-based or ether-based inert solvent in combination.

B) naphthalene-2,6-diol

[0054]

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Is dehydrohydronaphthalene-2,6-dione obtained by hydrogenating the compound by catalytic reduction or the above-described alkali metal reduction and, if necessary, oxidizing the hydroxyl group to a carbonyl group with chromic acid or the like.

[0056]

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By converting the compound into a monoacetal, decahydronaphthalene-2,6-dione monoacetal represented by the general formula (I) can be obtained.

Here, the monoacetalization is carried out by using a diol (HO
-Z-OH) was adjusted to obtain (I), isolating (I) from the mixture of the starting material decahydronaphthalene-2,6-dione and diacetal, or (I) Can be used as an insoluble matter or the like and taken out of the system.

C) naphthalene-2,6-di-
And the resulting decahydronaphthalene-2,6-dione is converted to a diacetal, and the resulting general formula (IV)

[0060]

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(Wherein Z ¹ and Z ² have the same meanings as in the general formula (I), Z ³ and Z ⁴ have the same meanings as Z ¹ and Z ^2, and Z ¹ -Z ⁴ each have the same meaning May be different, but it is usually preferred that they are the same.) By partially hydrolyzing decahydronaphthalene-2,6-dionediacetal represented by the general formula (I), The decahydronaphthalene-2,6-dione monoacetal shown can be obtained.

D) naphthalene-2,6-diol

[0063]

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6-hydroxydecahydronaphthalen-2-one obtained by hydrogenating the compound by catalytic reduction or metal reduction

[0065]

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The decahydronaphthalene-2,6-dionemonoacetal of the general formula (I) can be produced by acetalizing the carbonyl group of the formula (1) and then oxidizing the hydroxyl group.

The resulting (I) decahydronaphthalene-2,6-
Dione monoacetal is represented by the general formula (V)

[0068]

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(Wherein W is a metal or metal-containing group capable of nucleophilic addition to a carbonyl group, and Li, Na,
MgCl, MgBr, MgI, B ( OH) 2, SiX 1 X 2 X 3, or ZrX ¹ X is ² X ^3, or the like can be used, Li, MgCl, MgBr or MgI are preferred. Here, X ¹ , X ² and X ³ represent a halogen atom or an alkoxyl group having 4 or less carbon atoms, and may be the same or different. X ^a , X ^b and X ^c each independently represent a hydrogen atom or a fluorine atom, and it is preferable that at least one is a hydrogen atom. Y is a hydrogen atom, a halogen atom of fluorine, chlorine or bromine, a fluorine atom or an alkyl or alkoxyl group having 1 to 12 carbon atoms which may be substituted by an alkoxyl group having 1 to 7 carbon atoms, such as an oxazoline ring; Represents a protected hydroxyl group such as a protected cyano group, a benzyloxy group or a tetrahydropyranyloxy group, or a protected carboxyl group such as a t-butoxycarbonyl group. ), The resulting alcohol is dehydrated in the presence of an acid catalyst to give an octahydronaphthalene derivative, and if deacetalization occurs, it is reacetalized and hydrogenated. The isomerization is carried out as required to obtain an alkenyldecalin derivative,
(VI)

[0070]

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(Wherein X ^a , X ^b , X ^c and Y have the same meaning as in the general formula (V)), and a 6-phenyldecahydronaphthalen-2-one derivative represented by the following formula is easily obtained. The present invention also provides a method for producing the same.

[0072]

EXAMPLES Examples of the present invention are shown below to further explain the present invention. However, the invention is not limited to these examples. The structure of the compound was confirmed by infrared absorption spectrum (IR).

Example 1 Synthesis of decahydronaphthalene-2,6-dione monoethylene acetal (1) (1-a) Synthesis of octahydronaphthalene-2,6-dione monoethylene acetal

[0074]

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Cyclohexane-1,4-dione monoethylene acetal (100 g) was dissolved in toluene (400 mL), pyrrolidine (96.2 mL) was added, and the mixture was heated and refluxed for 4 hours in a device equipped with a water separator until water was no longer distilled. . Heating was continued as it was, and after distilling off pyrrolidine and toluene, the temperature was returned to room temperature. 400 mL of toluene was added, and a solution of 54 g of methyl vinyl ketone in 100 mL of toluene was added dropwise while cooling to 20 ° C. or lower. After the dropwise addition, the mixture was heated under reflux for 8 hours, and then allowed to cool to room temperature. A mixed solution of 61 g of sodium acetate, 74 mL of glacial acetic acid and 74 mL of water was added, and the mixture was heated under reflux for 5 hours, and then allowed to cool to room temperature. The organic layer was separated, washed with water and the solvent was distilled off.
The obtained oil was distilled under reduced pressure, and recrystallized from a mixed solvent of hexane and ethyl acetate to give octahydronaphthalene-.
77.1 g of a white solid of 2,6-dione monoethylene acetal was obtained. (1-b) Synthesis of decahydronaphthalene-2,6-dione monoethylene acetal

[0076]

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1.4 L of liquid ammonia cooled to -40 ° C. or less
8.3 g of metallic lithium was added little by little and dissolved therein. While maintaining the internal temperature at -30 to -40 ° C, octahydronaphthalene-2,6-dione monoethylene acetal 7 obtained in (1-a)
0 g and 34 mL of t-butanol tetrahydrofuran (THF) 260
The mL solution was added dropwise, and stirring was continued for 30 minutes after the addition was completed. After excess lithium was decomposed by adding powdery ammonium chloride little by little, the temperature was raised to room temperature, and ammonia was distilled off. 200 mL of water was added, and the mixture was extracted with 200 mL of toluene. The organic layer was washed with 100 mL of saturated saline and dried over anhydrous sodium sulfate. After distilling off the solvent, distillation under reduced pressure (155 ℃ / 0.4KPa)
The mixture was further recrystallized from a mixed solvent of hexane and ethyl acetate to obtain 48 g of a white solid of decahydronaphthalene-2,6-dionemonoethyleneacetal. Melting point 62 ° C, IR (nujo
l) 880,940,1090,1150,1170,1710cm ^{- 1} (Example 2) Synthesis of decahydronaphthalene-2,6-dione monoethylene acetal (2) (2-a) of decahydronaphthalene-2,6-dione Synthesis

[0078]

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In an autoclave, naphthalene-2,6-di-
Dissolved in ethanol, add ruthenium oxide,
For 16 hours. After returning to room temperature, the catalyst was filtered through celite, and the solvent was distilled off. The residue was dissolved in acetone, chromium (VI) oxide and pyridine were added while cooling to 10 ° C. or lower, and the mixture was stirred for 30 minutes. Excess chromium (VI) oxide was decomposed by adding a small amount of methanol, toluene was added, and the mixture was washed with water. After removing the chromium salt by silica gel column chromatography (toluene), distillation was performed under reduced pressure to obtain an oil of decahydronaphthalene-2,6-dione. (2-b) Synthesis of decahydronaphthalene-2,6-dione monoethylene acetal

[0080]

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The decahydronaphthalene-2, obtained in (2-a)
16.6 g of 6-dione was dissolved in 150 mL of toluene, 6.2 g of ethylene glycol and 1.8 g of p-toluenesulfonic acid were added, and the mixture was heated and refluxed for 4 hours using a device equipped with a water separator until no distillate was found. After cooling to room temperature and washing with aqueous sodium bicarbonate, water was added, and the organic layer was separated. After washing with saturated saline, drying over anhydrous sodium sulfate, and evaporating the solvent, the obtained oil was purified by alumina column chromatography (diisopropyl ether + hexane), and further purified with a mixed solvent of hexane and ethyl acetate. The solid was recrystallized twice to obtain a white solid of decahydronaphthalene-2,6-dione monoethylene acetal.

Example 3 Synthesis of decahydronaphthalene-2,6-dione monoethylene acetal (3) (3-a) Synthesis of decahydronaphthalene-2,6-dione diethylene acetal

[0083]

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50.0 g of decahydronaphthalene-2,6-dione obtained in Example (2-a) was dissolved in 300 mL of toluene, and 56.0 g of ethylene glycol and 5.0 g of p-toluenesulfonic acid were dissolved.
Was added thereto, and the mixture was heated and refluxed for 4 hours using a device equipped with a water separator until no more distillate was found. After cooling to room temperature, water was added, the organic layer was separated, washed with water, dried over anhydrous sodium sulfate, the solvent was distilled off, and further recrystallized from a mixed solvent of hexane and ethyl acetate to give decahydronaphthalene-.
A white solid of 2,6-dionediethylene acetal was obtained. (3-b) Synthesis of decahydronaphthalene-2,6-dione monoethylene acetal

[0085]

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The decahydronaphthalene-2, obtained in (3-a)
61.0 g of 6-dione diethylene acetal was dissolved in 120 mL of toluene, 5.5 g of formic acid was added, and the mixture was stirred for 1 hour at room temperature. Water was added, and the organic layer was separated, washed with water and dried over anhydrous sodium sulfate. The solvent is distilled off, and alumina column chromatography (diisopropyl ether + hexane)
And recrystallized from a mixed solvent of hexane and ethyl acetate to obtain 35.3 g of decahydronaphthalene-2,6-dione monoethylene acetal as a white solid.

Example 4 Synthesis of decahydronaphthalene-2,6-dione monoethylene acetal (4) Synthesis of (4-a) 6-hydroxydecahydronaphthalen-2-one

[0088]

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In an autoclave, naphthalene-2,6-di-
100 g of ethanol in 500 mL of ethanol and 10 g of ruthenium oxide
Was added thereto and subjected to catalytic hydrogen reduction at 60 ° C. for 24 hours. After returning to room temperature, the catalyst was filtered through celite. After evaporating the solvent, the residue was purified by silica gel column chromatography (hexane + ethyl acetate) to obtain 15.8 g of an oily substance of 6-hydroxydecahydronaphthalen-2-one. Synthesis of (4-b) 6-hydroxydecahydronaphthalen-2-one ethylene acetal

[0090]

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15.8 g of 6-hydroxydecahydronaphthalen-2-one obtained in (4-a) was dissolved in 90 mL of toluene, and 8.8 g of ethylene glycol and 1.6 g of p-toluenesulfonic acid were added. The mixture was heated and refluxed for 4 hours until the distilled water disappeared. After cooling to room temperature and washing with aqueous sodium bicarbonate, water was added, the organic layer was separated, washed with water and dried over anhydrous sodium sulfate. After distilling off the solvent, the residue was distilled under reduced pressure to obtain 15.0 g of 6-hydroxydecahydronaphthalen-2-one ethylene acetal oil. (4-c) Synthesis of decahydronaphthalene-2,6-dione monoethylene acetal

[0092]

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15.0 g of 6-hydroxydecahydronaphthalen-2-one ethylene acetal obtained in (4-b) was added to acetone
Dissolve in 400 mL and cool chromium oxide (V
I) 10.0 g and pyridine 8.0 g were added and stirred for 30 minutes. 2-
After adding propanol, the solvent was distilled off. After removing the chromium salt by alumina column chromatography (toluene), the residue was distilled under reduced pressure, and further recrystallized from a mixed solvent of hexane and ethyl acetate to obtain 11.0 g of a white solid of decahydronaphthalene-2,6-dione monoethylene acetal. Obtained.

Example 5 6- (3,5-difluorophenyl)
Synthesis of decahydronaphthalen-2-one

[0095]

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2.28 g of metallic magnesium was suspended in 35 mL of THF, and a solution of 17.4-g of 3,5-diphenylbromobenzene in 20 mL of THF was added dropwise to prepare a Grignard reagent. Solution 10
A solution of decahydronaphthalene-2,6-dione monoethylene acetal (18.4 g) in THF (50 mL) was added dropwise while cooling to not more than ° C., and the mixture was returned to room temperature and stirred for 1 hour. After adding a saturated aqueous ammonium chloride solution, the organic layer was separated, washed with saturated saline, dried over anhydrous sodium sulfate, and the solvent was distilled off. The obtained oil (28.7 g) was dissolved in toluene, p-toluenesulfonic acid (1.4 g) was added, and the mixture was heated to reflux (4 hours) using a device equipped with a water separator until water no longer distilled.
Next, 3 mL of ethylene glycol was added, and the mixture was heated to reflux (4 hours) until no more water was distilled off. After cooling to room temperature, water was added, the organic layer was separated, washed with saturated saline, dried over anhydrous sodium sulfate, and the solvent was distilled off. 29.3 g of the obtained oil was dissolved in 300 mL of ethyl acetate, 6.0 g of 5% palladium on carbon was added, and the mixture was subjected to catalytic hydrogen reduction at room temperature for 20 hours. Then, the catalyst was filtered through celite, and the solvent was distilled off. The resulting oil
26.6 g was dissolved in 140 mL of N, N-dimethylformamide (DMF), 5.3 g of potassium t-butoxide was added, and the mixture was stirred at room temperature for 2 hours. After adding water and extracting with toluene, the organic layer was washed with saturated saline, dried over anhydrous sodium sulfate, and the solvent was distilled off. 24.7 g of the obtained oil was dissolved in 75 mL of toluene, 50 mL of formic acid was added, and the mixture was stirred at room temperature for 1 hour. Water was added, the organic layer was separated, washed with saturated saline, dried over anhydrous sodium sulfate, the solvent was distilled off, and 6- (3,5-difluorophenyl) decahydronaphthalen-2-one was obtained as an oil. Thing 2
1.1 g were obtained.

The following compounds are obtained in the same manner.

6- (4-fluorophenyl) decahydronaphthalen-2-one 6- (3,4-difluorophenyl) decahydronaphthalen-2-
ON 6- (3,4,5-trifluorophenyl) decahydronaphthalene
2-one 6- (4-trifluoromethoxyphenyl) decahydronaphthalen-2-one 6- (3-fluoro-4-trifluoromethoxyphenyl) decahydronaphthalen-2-one 6- (3,5-difluoro -4-trifluoromethoxyphenyl)
Decahydronaphthalen-2-one 6- (4-difluoromethoxyphenyl) decahydronaphthalen-2-one 6- (3-fluoro-4-difluoromethoxyphenyl) decahydronaphthalen-2-one 6- (3,5- Difluoro-4-difluoromethoxyphenyl) decahydronaphthalen-2-one 6- (4-chlorophenyl) decahydronaphthalen-2-one 6- (3-fluoro-4-chlorophenyl) decahydronaphthalen-2-one 6- ( 3,5-difluoro-4-chlorophenyl) decahydronaphthalen-2-one 6- (4-methoxyphenyl) decahydronaphthalen-2-one 6- (3-fluoro-4-methoxyphenyl) decahydronaphthalene-2- On 6- (3,5-difluoro-4-methoxyphenyl) decahydronaphthalen-2-one 6- (4-methylphenyl) decahydronaphthalen-2-one 6- (4-ethylphenyl) decahydronaphthalene-2 -One 6- (4-propylphenyl) decahydronaphtha Down-2-one

[0099]

According to the present invention, there is provided a method for producing decahydronaphthalene-2,6-dionemonoacetal which is a novel compound of the present invention, and a 6-phenyldecahydronaphthalen-2-one derivative is produced by using the method. Compared with known production methods, (a) high yield and (b) simple and (c)
It can be manufactured at low cost. Therefore, the novel compounds of the present invention are extremely useful industrially.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C07D 317/72 C07D 317/72

Claims (12)

[Claims] 1. A compound of the general formula (I) (In the formula, Z ¹ and Z ² are each independently a main chain carbon atom number of 1 to
The 6 alkyl groups or Z ¹ and Z ² are linked to each other to represent an alkylene group having 1 to 7 carbon atoms in the main chain. )) Decahydronaphthalene-2,6-dione monoacetal. 2. The decahydronaphthalene-2,6- according to claim ^1, wherein in the general formula (I), Z ¹ and Z ² are linked to each other to represent an alkylene group having 1 to 7 carbon atoms in the main chain. Zeon Monoacetar. 3. The decahydronaphthalene-2,6-dione monoaceta according to claim ^1, wherein in formula (I), Z ¹ and Z ² are linked to each other to represent an ethylene group or a 1,3-propylene group. Le. 4. A compound of the general formula (II) (In the formula, Z ¹ and Z ² are each independently a main chain carbon atom number of 1 to
The 6 alkyl groups or Z ¹ and Z ² are linked to each other to represent an alkylene group having 1 to 7 carbon atoms in the main chain. The cyclohexane-1,4-dionemonoacetal represented by the formula) is converted into an enamine with a secondary amine and then reacted with methyl vinyl ketone to give a compound of the general formula (III) (In the formula, Z ¹ and Z ² are each independently a main chain carbon atom number of 1 to
The 6 alkyl groups or Z ¹ and Z ² are linked to each other to represent an alkylene group having 1 to 7 carbon atoms in the main chain. To obtain octahydronaphthalene-2,6-dionemonoacetal represented by
2. The method for producing decahydronaphthalene-2,6-dionemonoacetal represented by the general formula (I) according to claim 1, wherein the hydrogen is reduced and hydrogenated. 5. The method according to claim 4, wherein the reduction is performed using an alkali metal in ammonia or an amine solvent. 6. Decahydronaphthalene-2,6-dione 2. The method for producing decahydronaphthalene-2,6-dione monoacetal represented by the general formula (I) according to claim 1, wherein the compound is converted into monoacetal. 7. Decahydronaphthalene-2,6-diol 7. The production method according to claim 6, wherein oxidizing is carried out to obtain decahydronaphthalene-2,6-dione. 8. The method of claim 1, wherein the decahydronaphthalene-2,6-diol is a naphthalene-2,6-dione. 8.A method according to claim 7, which is obtained by reducing hydrogenation.
The manufacturing method as described. 9. A compound of the general formula (IV) (In the formula, Z ¹ and Z ² are each independently a main chain carbon atom number of 1 to
6 alkyl groups or Z ¹ and Z ² are connected to each other to represent an alkylene group having 1 to 7 main chain carbon atoms, and Z ³ and Z ⁴ are each independently an alkyl group having 1 to 6 main chain carbon atoms. Alternatively, Z ³ and Z ⁴ are connected to each other to represent an alkylene group having 1 to 7 carbon atoms in the main chain, and Z ^{1 to} Z ⁴ may be the same or different. Wherein decahydronaphthalene-2,6-dionediacetal represented by the general formula (I) is partially hydrolyzed.
-A method for producing 2,6-dione monoacetal. 10. 10-Hydroxydecahydronaphthalene-2
-ON 2. The method for producing decahydronaphthalene-2,6-dione monoacetal represented by the general formula (I) according to claim 1, wherein the hydroxyl group is oxidized after acetalization of the compound. 11. A 6-hydroxydecahydronaphthalene-2
11. The method according to claim 10, wherein the -one is obtained by reducing and hydrogenating naphthalene-2,6-diol. 12. The decahydronaphthalene according to claim 1,
2,6-dione monoacetal has the general formula (V) (Wherein, W represents a metal or metal-containing group capable of nucleophilic addition to a carbonyl group, X ^a , X ^b and X ^c each independently represent a hydrogen atom or a fluorine atom, and Y represents a hydrogen atom A fluorine atom, a chlorine atom, a bromine atom, an alkyl group or an alkoxyl group having 1 to 12 carbon atoms which may be substituted by a fluorine atom or an alkoxyl group having 1 to 7 carbon atoms, a protected cyano group, A hydroxyl group or a protected carboxyl group), and after dehydration, followed by hydrogenation and deacetalization, a general formula (VI) Formula 10 (In the formula, X ^a , X ^b and X ^c each independently represent a hydrogen atom or a fluorine atom, and Y represents a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, a fluorine atom or an alkoxyl having 1 to 7 carbon atoms. 1 carbon atom which may be substituted by a group
Represents an alkyl group or an alkoxyl group, a protected cyano group, a protected hydroxyl group or a protected carboxyl group. A method for producing a 6-phenyldecahydronaphthalen-2-one derivative represented by the formula: