JP2002284756A - New fluorine-containing naphthalene compound and method for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a new fluorine-containing naphthalene compound having a wide usage that it is industrially significant as various intermediates or precursors, and a method for manufacturing the same. SOLUTION: New fluorine-containing naphthalene compounds expressed by the general formula (I). In the formula (I), Y is F, Cl, Br, I or CN. A group of the fluorine-containing naphthalene compounds can be produced by using 1-bromo-4-methylnaphthalene, which is easily available, as a starting material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to novel fluorine-containing naphthalene compounds and a method for producing them. The novel compounds according to the present invention are useful as precursors for organic fluorescent substances, liquid crystal materials, dyes, and the like, and are expected to have industrially significant wide applications as other various intermediates.

[0002]

BACKGROUND OF THE INVENTION The fluorinated naphthalene compounds of the present invention are novel and, therefore, the process for producing them is also novel.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide a novel fluorine-containing naphthalene compound represented by the following general formula (I), which is an industrially significant fluorine-containing organic compound, and a process for producing the same. is there.

[0004]

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However, in the formula (I), Y is F, C
1, Br, I or CN. That is, the present invention provides a novel 1-cyanomethyl-4- compound represented by the following formula (VI).
(Trifluoromethyl) naphthalene and its precursor, 1-halogenomethyl-4- (trifluoromethyl) naphthalene represented by the formula (V) [the halogen atom of the halogenomethyl group at the 1-position is F, Cl, Br or I. ]
It is about. The formula (V
1-Cyanomethyl-4- (trifluoromethyl) naphthalene represented by I) has an active methylene group and is therefore highly reactive with various compounds, and has an organic fluorescent substance, a dye, a liquid crystal material and the like having a trifluoromethyl group. Is a useful intermediate compound that is expected to be used for the production of Also, 1-halogenomethyl-4- (trifluoromethyl) naphthalene represented by the formula (V) is useful only as a precursor of 1-cyanomethyl-4- (trifluoromethyl) naphthalene of the formula (VI). In addition, it is a useful compound that is expected to be used as an intermediate for medical and agricultural chemicals and functional materials having a trifluoromethyl group because it has a reactive halogen atom.

[0006]

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[0007]

Means for Solving the Problems The present inventors have calculated the formula (V)
Novel 1-cyanomethyl-4- (trifluoromethyl) naphthalene of the formula (I) is prepared by converting 1-cyanomethyl-4- (trifluoromethyl) naphthalene of the formula (II)
Starting from -bromo-4-methylnaphthalene, the compound of the formula (I)
4-Methylnaphthalene-1-carboxylic acid represented by II), 1-methyl-4- (trifluoromethyl) naphthalene represented by formula (IV) and novel 1-halogenomethyl-4 represented by formula (V) -A process for producing via (trifluoromethyl) naphthalene has been found.

The specific method for producing the novel compound of the present invention will be described below. 1-bromo-4-methylnaphthalene represented by the formula (II) is a compound easily available as a reagent.

As a method for producing 4-methylnaphthalene-1-carboxylic acid represented by the formula (III) using 1-bromo-4-methylnaphthalene represented by the formula (II) as a raw material, for example, an inert gas The compound can be produced by preparing an organometallic compound from the compound of the formula (II) under an atmosphere and reacting the compound with carbon dioxide.

By reacting a bromo group of 1-bromo-4-methylnaphthalene represented by the formula (II) with an organolithium reagent or metallic magnesium in a solvent at a predetermined temperature for a predetermined time under stirring, an organometallic compound is obtained. Is prepared, and the solution and carbon dioxide are reacted with stirring at a predetermined temperature for a predetermined time to obtain a compound of the formula (III)
The 4-methylnaphthalene-1-carboxylic acid represented by the following formula can be produced. Since this reaction is a reaction that dislikes moisture, it is preferable to perform the reaction in a dry inert atmosphere such as nitrogen in the reaction vessel.

As the solvent for the above reaction, ether solvents such as diethyl ether and tetrahydrofuran can be used. The amount used is preferably 1 to 100 ml per 1 g of raw material.

When an organic lithium reagent is allowed to act,
Generally, it is necessary to carry out the reaction at an extremely low temperature, but in the case of this substrate, if the temperature is too low, the lithiation reaction does not proceed. Therefore,
The lithiation reaction temperature in this case is preferably in the range of -20 to 80C. When metallic magnesium is allowed to act, the temperature is preferably -30 to 200C. The amount of the organolithium reagent and the metal magnesium is preferably 1 to 2 times the molar amount of the raw material. The prepared solution containing the organometallic compound is reacted with carbon dioxide, and the carbon dioxide may blow carbon dioxide gas (gas) onto the gas-liquid interface of the solution containing the organometallic compound, or dry ice ( Solid). The amount used is 1 to 20 times the molar amount of the raw material. The reaction with carbon dioxide is preferably performed at a temperature of -50 to 30C. The reaction time is preferably 0.5 to 5 hours. After completion of the reaction, dilute sulfuric acid, dilute hydrochloric acid, etc. are added dropwise at a temperature not higher than room temperature, and after the usual post-treatment, purification is performed to obtain the compound represented by the formula (III) 4
-Methylnaphthalene-1-carboxylic acid can be produced.

Next, the carboxyl group of 4-methylnaphthalene-1-carboxylic acid represented by the formula (III) is fluorinated with sulfur tetrafluoride to give 1-methyl naphthalene compound represented by the formula (IV). 4- (trifluoromethyl) naphthalene can be produced.

The raw material represented by the formula (III) is free of a solvent,
Alternatively, it is preferable to use it after diluting with a chlorine-based solvent such as dichloromethane or chloroform or a hydrogen fluoride solvent. The amount of the solvent used is preferably from 0 to 20 per gram of the raw material.
Milliliters. The amount of sulfur tetrafluoride used as the fluorinating agent is preferably 2.0 to 6.0 times the molar amount of the raw material. A catalyst is preferably used for the reaction with sulfur tetrafluoride. As the catalyst, hydrogen fluoride, B
F ₃ , AsF ₃ , PF ₅ , TiF _{4 and the} like can be used. The amount used is preferably 0.01 to 1.0 times the molar amount of the raw material.

This reaction can be carried out under normal pressure, but when heating, it is preferred to carry out under pressure. Reaction pressure is 0-20
It is preferably in the range of MPa. The reaction temperature is -30 to
Preferably it is 180 ° C. The reaction time is preferably 1 to 24 hours. After completion of the reaction, a normal post-treatment and purification are performed to obtain 1-methyl-4- (trifluoromethyl), a naphthalene compound represented by the formula (IV).
Naphthalene can be produced.

Next, 1-methyl- represented by the formula (IV)
By reacting the methyl group of 4- (trifluoromethyl) naphthalene with a halogenating agent to directly monohalogenate, a novel naphthalene compound represented by the formula (V), 1-halogenomethyl-4- (trifluoro Methyl) naphthalene can be produced. As the halogenating agent, a normal halogenating agent for halogenating a benzyl group can be used, and examples thereof include a halogen molecule, N-halogenimides, and t-butyl hypohalite.
The yield of this direct monohalogenation reaction, the next step [formula (V
Production of Compound of I)], the halogen of the halogenomethyl group of 1-halogenomethyl-4- (trifluoromethyl) naphthalene represented by the formula (V) is a bromine atom. Is preferred for handling and is recommended.

Therefore, a method for producing 1-bromomethyl-4- (trifluoromethyl) naphthalene (compound represented by the formula (VII)) in which the halogen in the formula (V) is a bromine atom will be described below.

1-methyl-4-formula represented by the formula (IV)
A method for producing a novel 1-bromomethyl-4- (trifluoromethyl) naphthalene represented by the formula (VII) from (trifluoromethyl) naphthalene includes a brominating agent and a solvent in the presence of light or a peroxide catalyst. There is a method in which the reaction is performed at a predetermined temperature and for a predetermined time under medium and stirring.

As the brominating agent, bromine, N-bromosuccinimide (NBS), t-butyl hypobromite and the like can be used. The amount used is preferably 0.9 to the raw material.
~ 1.1 times the molar amount. As the peroxide, azobisisobutyronitrile (AIBN), benzoyl peroxide or the like can be used. The amount used is preferably 0 to the raw material.
About 0.1 times the molar amount. As the solvent, benzene, cyclohexane, tetrachloroethylene and the like can be used.
The amount used is preferably 1 to 20 ml per 1 g of raw material. The reaction temperature is preferably in the range of 0 to 150 ° C. The reaction time is preferably 0.5 to 5
Time. After completion of the reaction, 1-bromomethyl-4- (trifluoromethyl) naphthalene, which is a novel naphthalene compound represented by the formula (VII), can be produced by ordinary post-treatment and purification.

1-halogenomethyl- represented by the formula (V)
Starting from 4- (trifluoromethyl) naphthalene,
As a method for producing a novel 1-cyanomethyl-4- (trifluoromethyl) naphthalene represented by the formula (VI) from this, a compound of the formula (V) is stirred in a polar solvent under stirring.
There is a method of reacting with a cyanating agent at a predetermined temperature and a predetermined time.

As the polar solvent, dimethyl sulfoxide, N, N-dimethylformamide, N-methylpyrrolidone, acetone and the like can be used. The amount used is preferably 1 to 100 ml per 1 g of raw material.
Sodium cyanide, potassium cyanide and the like can be used as the cyanating agent. The amount used is preferably 1 to 2 times the molar amount of the raw material. The reaction temperature of cyanation is
It is preferably in the range of −50 to 150 ° C. The reaction time is preferably 0.5 to 5 hours. After completion of the reaction, a usual naphthalene compound represented by the formula (VI), 1-cyanomethyl-
4- (trifluoromethyl) naphthalene can be produced. In consideration of the yield and economic efficiency of the cyanation reaction, it is preferable in terms of handling that the halogen of the halogenomethyl group of 1-halogenomethyl-4- (trifluoromethyl) naphthalene represented by the formula (V) is a bromine atom. Recommended.

Starting from 1-bromomethyl-4- (trifluoromethyl) naphthalene of the formula (VII), a novel 1-cyanomethyl-4- (trifluoromethyl) naphthalene of the formula (VI) is produced therefrom. As a method for carrying out the method, a compound of the formula (VII) is
There is a method of reacting with a cyanating agent at a predetermined temperature and a predetermined time under stirring.

As the polar solvent, dimethyl sulfoxide, N, N-dimethylformamide, N-methylpyrrolidone, acetone and the like can be used. The amount used is preferably 1 to 100 ml per 1 g of raw material.
Sodium cyanide, potassium cyanide and the like can be used as the cyanating agent. The amount used is preferably 1 to 2 times the molar amount of the raw material. The reaction temperature of cyanation is
It is preferably in the range of −50 to 150 ° C. The reaction time is preferably 0.5 to 5 hours. After completion of the reaction, a usual naphthalene compound represented by the formula (VI), 1-cyanomethyl-
4- (trifluoromethyl) naphthalene can be produced.

Examples of various aspects of the present invention will be described below. The method for producing the novel compounds in the present invention is not limited to the specific embodiments and details described in the examples.

[0025]

EXAMPLES Preparation of 4 -methylnaphthalene-1-carboxylic acid
Concrete Example 1 cooling bath, gas blowing tube, under a nitrogen atmosphere 500mL glass flask equipped with a thermometer and a pressure equalizing pipe with a dropping funnel, 1-bromo-4-methylnaphthalene 20 g (0.0
90 mol) and 250 ml of diethyl ether. After cooling to about 0 ° C., 61.6 ml (0.095 mol) of a hexane solution of n-butyllithium (1.54 M) was added dropwise with stirring over 0.5 hours so that the liquid temperature was 5 ° C. or lower. did. After completion of the dropwise addition, stirring was continued at about 0 ° C. for further 30 minutes. Next, 0.1 L /
Minutes were blown for 2 hours. Since this reaction is an exothermic reaction, it was carefully blown so that the liquid temperature was 15 ° C. or lower. After completion of the reaction, 100 ml of 5% hydrochloric acid was added dropwise with stirring.
After mixing, the organic phase was separated. The aqueous phase is chloroform 100
The extracted chloroform phase and the separated organic phase were mixed with each other. The combined organic phases are dried over anhydrous sodium sulfate,
After the sodium sulfate was filtered off, the solvent was distilled off under reduced pressure. The obtained crude product was recrystallized from chloroform to obtain a yellow solid of 4-methylnaphthalene-1-carboxylic acid. The LC purity was 98%, and the yield was 14.3 g (84.9%).

The structure of the product was confirmed by nuclear magnetic resonance analysis and the like. Nuclear magnetic resonance analysis [manufactured by VARIAN: Gemini
200] are as follows. ¹ H-NMR (solvent: CDCl ₃ , standard: tetramethylsilane) δ 9.16 ppm (dd, J = 1.62, 7.34H)
z, 1H, Ar H) 8.33ppm (d, J = 7.40Hz, 1H, Ar
H ) 8.10 ppm (dd, J = 1.88, 7.34 Hz,
1H, Ar H) 7.64ppm (m , 2H, Ar H) 7.41ppm (d, J = 7.54Hz, 1H, Ar
H) 2.79ppm (s, 3H, ArC H 3) 1 - methyl-4- (trifluoromethyl) naphthalene
Production Example 2 20 equipped with a stirrer, a gas introduction pipe, a gas abandonment pipe, a thermometer, and a cooling (heating) bath installed in a walk indraft.
4-methylanthracene-1-carboxylic acid 1 in a 0 ml stainless steel autoclave container under a nitrogen atmosphere.
0 g (0.054 mol) was charged, sealed, and cooled to -50 ° C. 50 g of anhydrous hydrogen fluoride and then 23 g (0.21 mol) of sulfur tetrafluoride were charged from the gas inlet tube and sealed. While stirring, heat the liquid temperature to 80 ° C.,
Stirring was continued at 5 ° C. for 5 hours. After the reaction is completed, at around 30 ° C,
The gas component and anhydrous hydrogen fluoride were discarded to the alkaline scrubber, and the inside of the vessel was sufficiently replaced with nitrogen gas. Extract the oily substance in the container with 100 ml of chloroform,
It was washed with 100 ml of a saturated aqueous solution of potassium carbonate. The organic phase was dried over anhydrous sodium sulfate, and after removing sodium sulfate by filtration, the solvent was distilled off under reduced pressure. The obtained crude product was purified by silica gel column chromatography to obtain 1-methyl-4- (trifluoromethyl) naphthalene as a light brown oil. LC purity was 98% and yield was 7.8 g (yield 69.1%).

The structure of the product was confirmed by nuclear magnetic resonance analysis or the like. Nuclear magnetic resonance analysis [manufactured by VARIAN: Gemini
200] are as follows. ¹ H-NMR (solvent: CDCl _3, standard: tetramethylsilane) δ 8.22ppm (m, 1H, Ar H) 8.10ppm (m, 1H, Ar H) 7.77ppm (d, J = 7. 52Hz, 1H, Ar
H) 7.63ppm (m, 2H, Ar H) 7.35ppm (d, J = 7.52Hz, 1H, Ar
H) 2.75ppm (s, 3H, ArC H 3) 19 F-NMR ( solvent: CDCl _3, standard: CFC
l ₃ ) δ -59.10 ppm (s, 3F, CF ₃ ) 1-bromomethyl-4- (trifluoromethyl) naphtha
Production Example 3 5 g (0.024 mol) of 1-methyl-4- (trifluoromethyl) naphthalene and 50 ml of benzene were placed in a 200 ml glass flask equipped with a heating bath, a thermometer and a cooling condenser under a nitrogen atmosphere. N-bromosuccinimide 4.36
g (0.025 mol), and benzoyl peroxide 0.23
g (0.95 mmol) and heated to reflux with stirring for 1 hour. After completion of the reaction, the reaction solution was cooled to 5 ° C. or lower, and succinimide was separated by filtration. 5% filtrate
After washing with 50 ml of an aqueous solution of sodium hydroxide, drying over anhydrous sodium sulfate, sodium sulfate was filtered off, and benzene was distilled off under reduced pressure. The obtained crude product was purified by silica gel column chromatography to give 1-bromomethyl-
4- (Trifluoromethyl) naphthalene was obtained as a pale yellow oil. The LC purity was 99%, and the yield was 6.2 g (90.2%).

The structure of the product was confirmed by nuclear magnetic resonance analysis and the like. Nuclear magnetic resonance analysis [manufactured by VARIAN: Gemini
200] are as follows. ¹ H-NMR (solvent: CDCl ₃ , standard substance: tetramethylsilane) δ 8.26 ppm (m, 2H, Ar H ) 7.9 to 7.5 ppm (m, 4H, Ar H ) 4.93 ppm (s, ^{_{2H, ArC H 2) 19 F}} -NMR ( solvent: CDCl _3, standard: CFC
l ₃ ) δ -59.34 ppm (s, 3F, CF ₃ ) 1 -cyanomethyl -4- (trifluoromethyl) naphtha
Production of Len Example 4 In a 200 ml glass flask equipped with a heating bath, a thermometer and a dropping funnel equipped with a pressure balance tube, under a nitrogen atmosphere, 50 ml of dimethyl sulfoxide and 1 g of sodium cyanide (0.1 g).
020 mol) and heated to about 70 ° C. to form a homogeneous solution. After cooling to room temperature, 3 g of 1-bromomethyl-4- (trifluoromethyl) naphthalene (0.
010 mol) was dissolved in 10 ml of dimethyl sulfoxide, and the whole solution was quickly added from a dropping funnel.
The organic phase was separated, and the aqueous phase was extracted with benzene (30 ml × 3 times). The separated organic phase and the extract were mixed, dried over anhydrous magnesium sulfate, and then magnesium sulfate was filtered off. The solvent was distilled off under reduced pressure, and the obtained crude product was purified by silica gel column chromatography to obtain 1-cyanomomethyl-4- (trifluoromethyl) naphthalene as a pale yellow solid. The LC purity was 99%, and the yield was 2.4 g (71.5%).

The structure of the product was confirmed by nuclear magnetic resonance analysis and the like. Nuclear magnetic resonance analysis [manufactured by VARIAN: Gemini
200] are as follows. ¹ H-NMR (solvent: CDCl ₃ , standard substance: tetramethylsilane) δ 8.34 to 8.22 ppm (m, 1H, Ar H ) 7.97 ppm (dd, J = 3.18, 6.74 Hz,
1H, Ar H ) 7.89 ppm (d, J = 7.54 Hz, 1H, Ar
H) 7.78~7.64ppm (m, 3H, Ar H) 4.21ppm (s, 2H, ArC H 2) 19 F-NMR ( solvent: CDCl _3, standard: CFC
l ₃ ) δ -59.44 ppm (s, 3F, CF ₃ )

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Naoto Takechi 1497 Shibukawa-shi, Gunma Prefecture Inside Shibukawa Plant, Kanto Denka Kogyo Co., Ltd. 72) Inventor Yasushi Fukai 1497 Shibukawa-shi, Gunma Kanto Denka Kogyo Co., Ltd.Shibukawa Plant (72) Inventor Tadao Nakaya 9 Kirihara-cho, Fujisawa-shi, Kanagawa Prefecture Taiho Industrial Co., Ltd. Tatsuro 9 Kirihara-cho, Fujisawa-shi, Kanagawa Pref. In the Central Research Laboratory (72) Inventor Yuki Noguchi 9 Kirihara-cho, Fujisawa-shi, Kanagawa Pref. 9 Kirihara-cho, Ichi-ho Co., Ltd. Central Research Laboratory F-term (reference) 4H006 AA01 AB84 AC30 AC54 EA23 QN14 4H039 CA50 CD10 CD20

Claims (5)

[Claims] 1. A naphthalene compound represented by the following general formula (I): Here, in the formula (I), Y is F, Cl, Br, I or CN. 2. A 1-methyl- of the following formula (IV) obtained from 1-bromo-4-methylnaphthalene of the following formula (II) via 4-methylnaphthalene-1-carboxylic acid of the following formula (III): A method for producing 1-halogenomethyl-4- (trifluoromethyl) naphthalene of the following formula (V) by monohalogenating the methyl group of 4- (trifluoromethyl) naphthalene: Here, in the formula (V), X is F, Cl, Br or I. 3. 1-halogenomethyl-4 of the following formula (V)
A method for producing 1-cyanomethyl-4- (trifluoromethyl) naphthalene of the following formula (VI) by reacting the halogenomethyl group of-(trifluoromethyl) naphthalene with cyanide ion: Here, in the formula (V), X is F, Cl, Br or I. 4. A 1-methyl-4- (trifluoromethyl) naphthalene of the following formula (VII) by monobrominating a methyl group of 1-methyl-4- (trifluoromethyl) naphthalene of the following formula (IV): How to manufacture. Embedded image 5. A compound of the formula (VII):
A method for producing 1-cyanomethyl-4- (trifluoromethyl) naphthalene of the following formula (VI) by cyanating a bromomethyl group of 4- (trifluoromethyl) naphthalene. Embedded image