JP3390190B2 - 1,3-bis (3-aminophenoxy) -5-trifluoromethylbenzene and method for producing the same - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a novel aromatic diamino compound having a trifluoromethyl group and a method for producing the same. These compounds can be used as starting materials for polyimides, polyamides, polyamideimides, bismaleimides and epoxy resins.

[0002]

2. Description of the Related Art Polyimide resins belong to the highest class among organic polymers in various properties such as heat resistance, mechanical properties and adhesiveness, and by utilizing these properties, various heat resistant mechanical parts and adhesives It is well known that it is widely used in agents and electronic material parts. However, the polyimide resin is
There is a problem that the dielectric constant is higher than that of coloring or low dielectric resin such as Teflon.

Coloring is an extremely important issue in the development of optical materials such as optical communication cables and filters having high heat resistance and high reliability, and liquid crystal display panels. Specifically, when the yellowness index (hereinafter abbreviated as YI) which is an index of yellowness is used as a parameter, 4,
12 for polyimide (trade name Kapton) consisting of 4'-diaminodiphenyl ether and pyromellitic dianhydride
A polyimide (trade name Upilex) composed of 9,4,4′-diaminodiphenyl ether and biphenyltetracarboxylic dianhydride is a polyimide composed of 125,3,3′-diaminobenzophenone and benzophenone tetracarboxylic dianhydride (LRAC-TPI). ) Is 50, which is very high. In order to use the above-mentioned various optical materials, a polyimide resin having a YI of 10 or less, and preferably having a YI of about 4 to 8, which is comparable to polycarbonate currently widely used for optical materials, is desired.

The dielectric constant is a very important parameter in the field of electronic materials, and the dielectric constant of the polyimide resin currently commercialized is 3. Kapton.
5 / 1MHz, Upilex 3.5 / 1MHz,
In LRAC-TPI, it is 3.7 / 1 MHz. Current,
Polyimide resin has already been used as an insulating material for a flexible printed circuit board, but with the recent high integration of electronic circuits, an insulating material having a lower dielectric constant, specifically, a dielectric constant of 2.9. A polyimide resin having a frequency of / 1 MHz or less is desired.

Both of the above two problems are caused by the electron transfer in the resin. The permittivity restricts the electron transfer in the polymer main chain, and the coloring is common in the main chain. It can be improved by cutting the system. As a specific method, it is known that introduction of an electron-withdrawing fluorine atom into a polyimide molecular unit is effective. For example, an aromatic diamine containing a hexafluoroisopropylidene group is disclosed as a polyimide monomer for a low dielectric constant material (Japanese Patent Laid-Open No. 1-19).
0652). However, these aromatic diamines have industrial problems such as a multi-step synthetic method and insufficient heat fluidity when molding and processing a polyimide resin obtained from them. Further, as the diamine having a trifluoromethyl group in the molecule, for example, 4,4′-bis (4-amino-5-trifluoromethylphenyloxy) biphenyl represented by the formula (4) (chemical formula 4) is It is disclosed (WO8404041).

[0006]

[Chemical 4]

However, since this compound has a trifluoromethyl group which is an electron-withdrawing group in the terminal aromatic ring where an amino group is present and in the ortho position, it reacts with an acid anhydride due to an electronic factor. It is difficult to increase the degree of polymerization. Further, since the amino group is in the para position with respect to the bonding group, the obtained polyimide has a rigid structure, and there is a drawback that molding is difficult.

[0008]

SUMMARY OF THE INVENTION An object of the present invention is to provide a raw material for polyimide, which has a low dielectric constant, is colorless and transparent, and is excellent in moldability.

[0009]

The present inventors have completed the present invention as a result of intensive studies to solve the above problems. That is, the present invention provides 1,3-bis (3-aminophenoxy) -5-trifluoromethylbenzene represented by formula (1) (formula 5) (hereinafter abbreviated as m-APTFB), and formula ( 2) 3,5-dinitrobenzotrifluoride represented by (Chemical Formula 6) (hereinafter abbreviated as DNBTF) and m-nitrophenol (hereinafter abbreviated as MNP) in the presence of a base, in an aprotic solvent. 1,3-bis (3-nitrophenoxy) -5-trifluoromethylbenzene (hereinafter abbreviated as NPTFB) of formula (3) ，
The present invention relates to a method for producing 3-bis (3-aminophenoxy) -5-trifluoromethylbenzene.

[0010]

[Chemical 5]

[0011]

[Chemical 6]

[0012]

[Chemical 7] A polymer obtained by using the diamino compound of the present invention as a monomer unit exhibits high melt fluidity, and also exhibits low dielectric constant and colorless transparency derived from a trifluoromethyl group. Furthermore, since the trifluoromethyl group, which is an electron-withdrawing group, is not in the same aromatic ring as the amino group, the degree of polymerization is not lowered due to electronic factors.

The method for producing m-APTFB of the present invention will be specifically described below. The compounds of the present invention include DNBTF and M
It can be produced in high yield by reducing NPFB obtained by reacting NP in the presence of a base in an aprotic polar solvent. The raw material DNBTF is a known method, for example, the Journal of American Chemical Society.
74 , 3011-14, it is obtained by reacting a mixed acid with benzotrifluoride. In the method of the present invention, MNP may be at least 2 times the molar amount of DNBTF, and in consideration of complexity of post-treatment, cost, etc.
It is preferable to use 2.5 times the molar amount.

The base used in the method of the present invention is an alkali metal carbonate, hydrogen carbonate, hydroxide or alkoxide, which is potassium carbonate, potassium hydrogen carbonate, potassium hydroxide, sodium carbonate, sodium hydroxide, Examples thereof include sodium hydrogen carbonate, lithium carbonate, lithium hydroxide, sodium methoxide, potassium isopropoxide and the like. The amount of these bases used depends on the raw material DNBTF.
It is sufficient if the amount is equivalent to or more than the nitro group of
~ 2 times equivalent is enough.

The aprotic solvent used in the method of the present invention includes formamide, N-methylformamide,
Examples include N, N-dimethylformamide, N, N-diethylformamide, N, N-dimethylacetamide, N-methylpyrrolidone, 1,3-dimethyl-2-imidazolidinone, dimethyl sulfoxide, sulfolane and the like. The amount of these solvents to be used is not particularly limited, but usually 1 to 10 times by weight of the raw material is sufficient. In the method of the present invention, in order to promote the reaction, a copper powder and a copper-based compound or a phase transfer catalyst such as crown ether, polyethylene glycol, quaternary ammonium salt or quaternary phosphonium salt may be used as a catalyst. not useable. The reaction temperature is usually in the range of 80 to 250 ° C,
It is preferably in the range of 100 to 200 ° C.

As a general reaction method of the present invention, a predetermined amount of MNP, a base and an aprotic solvent are charged,
After making MNP into an alkali metal salt, DNBTF may be added and reacted, or all the raw materials including DNBTF may be simultaneously added in advance and the temperature may be raised to be reacted. In addition, the method is not limited to these, and can be implemented by other methods. When water is present in the reaction system, as a method for removing water, there is a method in which nitrogen gas or the like is vented to exhaust the gas to the outside of the system during the reaction. Generally, benzene, toluene, xylene, chlorobenzene are used. A method in which a small amount of etc. is used to remove it out of the system by azeotropic distillation is often used. The end point of the reaction can be determined by thin layer chromatography or high performance liquid chromatography while observing the reduction of the raw materials. After the completion of the reaction, the crude dinitro compound is obtained after being concentrated or discharged as it is into water or the like. This one is
It can be purified by recrystallization or sludging with a solvent. The corresponding diamino compound can be produced by reducing the dinitro compound obtained by the above production method.

The method for reducing the dinitro compound is not particularly limited, and a method for reducing an ordinary nitro group to an amino group (for example, Shin Jikken Kagaku Koza, Vol. 15, Oxidation and Reduction II,
Maruzen (1977)) can be applied, but industrially catalytic reduction is preferred. In the case of catalytic reduction, the reduction catalyst used may be a metal catalyst generally used for catalytic reduction, such as nickel, palladium, platinum, rhodium, ruthenium, cobalt or copper. Industrially, it is preferable to use a palladium catalyst. Although these catalysts can be used in the metallic state,
Usually, it is used by supporting it on the surface of a carrier such as carbon, barium sulfate, silica gel, alumina, or celite, or as a Raney catalyst for nickel, cobalt, copper, or the like. The amount of the catalyst used is not particularly limited, but is 0.01 to 1 as a metal with respect to the dinitro compound as a raw material.
The range is 0% by weight, usually 2 to 8% by weight when used in a metal state, and 0.1 when loaded on a carrier.
Is in the range of up to 5% by weight.

The reaction solvent used in the reduction reaction is not particularly limited as long as it is inert to the reaction, and examples thereof include alcohols such as methanol, ethanol and isopropyl alcohol, ethylene glycol and propylene. Glycols such as glycols, ethers, dioxane, tetrahydrofuran, ethers such as methyl cellosolve are preferred, but in some cases, hexane, aliphatic hydrocarbons such as cyclohexane, benzene, toluene, aromatic hydrocarbons such as xylene, Esters such as ethyl acetate and butyl acetate, dichloromethane, chloroform, carbon tetrachloride, 1,2-dichloroethane,
Halogenated hydrocarbons such as 1,1,2-trichloroethane and tetrachloroethane and N, N-dimethylformamide can also be used. When a reaction solvent that is immiscible with water is used and the reaction proceeds slowly, it can be accelerated by adding a commonly used phase transfer catalyst such as a quaternary ammonium salt or a quaternary phosphonium salt. . The amount of the solvent used is sufficient to suspend or completely dissolve the raw material, and is not particularly limited, but usually 0.5 to 10 times by weight of the raw material is sufficient.

The reaction temperature is not particularly limited and is 20 to 200.
The temperature is in the range of ℃, but is preferably in the range of 20 to 100 ℃. The reaction pressure is about atmospheric pressure to 50 atm. In the reaction, a catalyst is usually added in a state where raw materials are dissolved or suspended in a solvent, and then hydrogen is introduced at a predetermined temperature with stirring to carry out a reduction reaction. The end point of the reaction can also be determined by the amount of absorbed hydrogen, thin layer chromatography, high performance liquid chromatography, or the like. After completion of the reaction, the catalyst used for the reduction is removed, and then the reaction solvent is distilled off to obtain the desired product.

[0020]

EXAMPLES The method of the present invention will now be described in more detail by way of examples. The invention is not thereby limited in any way. Example 1 A four-necked flask equipped with a thermometer, a reflux condenser, and a stirrer was charged with N, N-dimethylformamide (DMF) 250.
g, toluene 25 g, 3,5-dinitrobenzotrifluoride 40 g (0.169 mol), m-nitrophenol 48.3 g (0.347 mol) and potassium carbonate 28 g (0.203 mol) are charged respectively, and the mixture is stirred. After the temperature was raised to 150 ° C, the reaction was carried out at 150 ° C for 25 hours. The purity of 1,3-bis (3-nitrophenoxy) -5-trifluoromethylbenzene at the end of the reaction is HP.
LC showed 80%. After completion of the reaction, cool to 90 ° C,
The inorganic salts were removed by filtration. Water 1 in the filtrate
90 ml was added and cooled to room temperature to crystallize the desired product. The precipitated crystals were separated by filtration and recrystallized with methyl cellosolve to give 1,3-bis (3-
Nitrophenoxy) -5-trifluoromethylbenzene was obtained. Melting point: 117.6-118.5 ° C, yield: 5
4.9 g, 77% yield Elemental analysis (C ₁₉ H ₁₁ N ₂ O ₆ F ₃ ) C H N F Calculated value (%) 54.30 2.64 6.67 13.56 Measured value (%) 54 .14 2.62 6.59 13.51

Example 2 A reducing device equipped with a thermometer, a reflux condenser, and a stirrer,
55 g of 1,3-bis (3-nitrophenoxy) -5-trifluoromethylbenzene, (0.131 mol), 150 g of methyl cellosolve and 5 g of 5% -Pd / C (5
(0% water-containing product) was charged and the reaction was carried out at 70 to 80 ° C. for 4 hours under a hydrogen atmosphere. After the reaction was completed, the catalyst was filtered off, heated to 90 ° C., 140 g of water was added, and then cooled to room temperature to crystallize the desired product, which was then filtered off and dried under reduced pressure to give a white solid. 1,3-bis (3-aminophenoxy) -5-trifluoromethylbenzene was obtained. Melting point 98.0-9
8.6 ° C., yield 41 g, yield 87% ¹ H-NMR δ (CDCl ₃ , ppm) 3.56 (4H (1), s) 6.31 to 6.51 (6H (2), m ) 6.81 to 7.24 (5H (3), m) (1) to (3) represent the positions of the following formula (Formula 8).

[0022]

[Chemical 8] Elemental analysis (C ₁₉ H ₁₅ N ₂ O ₂ F ₃ ) C H N F Calculated value (%) 63.33 4.20 7.77 15.82 Measured value (%) 63.38 4.26 7.75 15 .79

Example of use The diamino compound obtained in the example and 2,2-bis (3,4-dicarboxyphenyl) -1,1,1,3
3,3-hexafluoropropane dianhydride (6F-B
Polyimide was obtained by condensation with A). The physical properties of the obtained film were as follows. Glass transition temperature Tg: 201 ° C. Melting point Tm: None Viscosity η: 1.19 dl / g (35
C.) [Polyimide 0.5 g / 100 cc (N, N-dimethylacetamide)] Dielectric constant 2.89 / 60 Hz 2.87 / 3 kHz 2.84 / 1 MHz YI 8

[0024]

According to the present invention, as a raw material for polyimide, which is colorless and transparent, has a low dielectric constant, and is excellent in moldability,
It has become possible to provide a very useful aromatic diamino compound.

─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-4-312544 (JP, A) JP-A-3-6528 (JP, A) JP-A-4-255827 (JP, A) JP-A-6- 116236 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) C07C 217/00 C07C 213/00 CA (STN) REGISTRY (STN)

Claims (2)

(57) [Claims] 1. 1,3-Bis (3-aminophenoxy) -5-trifluoromethylbenzene represented by the formula (1) (formula 1). [Chemical 1] 2. A 3,5-dinitrobenzotrifluoride represented by the formula (2) (chemical formula 2), and 1,3-bis (3-nitrophenoxy) -5-trifluoromethyl represented by the formula (3) (Chemical Formula 3) obtained by condensing m-nitrophenol in the presence of a base in an aprotic solvent. Benzene Is reduced, The method for producing 1,3-bis (3-aminophenoxy) -5-trifluoromethylbenzene according to claim 1.