CN101560166B - Method for preparing 1,3-di(2-trifluoromethyl-4-aminophenoxy) benzene - Google Patents

Abstract

The present invention relates to a kind of preparation method of 1,3-bis(2-trifluoromethyl-4-aminophenoxy)benzene, comprising: 1,3-bis(2-trifluoromethyl-4-nitro Add phenoxy)benzene, organic solvent and catalyst into the autoclave, pass hydrogen, stir, replace the residual air, continue to pass hydrogen, heat up to 40°C-80°C, maintain the pressure in the reactor at 0.4MPa-1.2MPa, and keep After reacting for 2 to 5 hours, cool the reaction system to room temperature, slowly release the pressure, and pass nitrogen to replace all the residual hydrogen to ensure the inert atmosphere in the autoclave, filter, recover the filter residue, keep the mother liquor, and put it in the mother liquor Deionized water was added dropwise while stirring, and a white solid product was precipitated, filtered, washed, and dried to obtain 1,3-bis(2-trifluoromethyl-4-aminophenoxy)benzene as a solid. The method has the advantages of simple process, low cost, environmental friendliness, high purity and yield, and is suitable for industrial production.

Description

Preparation method of 1,3-bis(2-trifluoromethyl-4-aminophenoxy)benzene

technical field

The invention belongs to the field of preparation of aromatic fluorine-containing organic compounds, in particular to a preparation method of 1,3-bis(2-trifluoromethyl-4-aminophenoxy)benzene.

Background technique

Aromatic polyimide has excellent thermal stability, chemical stability, excellent mechanical properties, electrical properties and resistance to organic solvents, and has been widely used in aerospace, electronic microelectronics, electrical and other fields. Because of its high temperature resistance, high strength, corrosion resistance, good insulation, and simple film forming process, it is an excellent functional material that can meet the performance requirements of LCD (liquid crystal display).

Fluorine-containing polyimide materials not only have the above-mentioned excellent properties, but also have very excellent optical transparency, flame retardancy and excellent molding processability. In addition, its dielectric constant, dielectric loss and water absorption are relatively low.

Fluorine-containing polyimide materials have important application values in certain fields, such as flexible solar radiation protection devices, liquid crystal alignment films, gas separation films, passivation coatings or interlayer insulation media for integrated circuits, and waveguides for communication connectors materials, electrical insulating dielectric films for flexible printed circuit boards, etc.

Yu Xinhai [Chemical New Materials, 2003, 31(10): 24~27, 31] disclosed 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane and its fluorine-containing polyimide Process for the preparation of amine materials.

Yu Xinhai [Insulation Materials, 2007, 40(4): 1~5, 8] discloses the preparation method of 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane, which is not only for the preparation of fluorine-containing poly An important raw material for benzoxazole polymer materials, and also an important raw material for preparing fluorine-containing and phenolic hydroxyl-containing polyimide resins.

Chinese patent CN101234991A discloses the preparation method of 2,2-bis[4-(2,4-diaminophenoxy)phenyl]hexafluoropropane, which is also an important raw material for preparing fluorine-containing polyimide resin, especially It is an important raw material for preparing fluorine-containing hyperbranched polyimide resin.

Chinese patent CN101245028A discloses the preparation method of 2,2-bis[3-amino-4-(4-aminophenoxy)phenyl]hexafluoropropane, which is also an important raw material for preparing fluorine-containing polyimide resin, especially It is an important raw material for preparing fluorine-containing highly branched polyimide resin.

Chinese patent CN101245023A discloses the preparation method of 2,2-bis[3-amino-4-(2,4-dinitrophenoxy)phenyl]hexafluoropropane, which is also the preparation method of fluorine-containing polyimide resin important raw material.

1,3-bis(2-trifluoromethyl-4-aminophenoxy)benzene is one of the important raw materials for the synthesis of aromatic fluorine-containing polyimide polymer materials.

Chinese patent CN1361097A discloses the preparation method of 1,3-bis(2-trifluoromethyl-4-aminophenoxy)benzene, which is characterized in that: 170 parts of 1,3-bis(2- Trifluoromethyl-4-nitrophenoxy)benzene, 100 parts iron powder and 150 parts ethanol aqueous solution. Under rapid stirring and reflux, 8 parts of aqueous hydrochloric acid were slowly added dropwise, and refluxed for 2 hours. Then add ammonia water, adjust the solution to neutral, and stir for 0.5 hours. The solid was removed by filtration, and the filtrate was concentrated by distillation and left for 10 hours. After filtration, the crystals were washed three times with absolute ethanol, and then dried to obtain 1,3-bis(2-trifluoromethyl-4-aminophenoxy)benzene.

K.Xie, J.G.Liu, et al. [Soluble fluoro-polyimides derived from 1, 3-bis (4-amino-2-trifluoromethylphenoxy) benzene and dianhydrides, Polymer, 2001, 42: 7267-7274] published 1, 3 -The preparation method of bis(2-trifluoromethyl-4-aminophenoxy)benzene is characterized in that: concentrated hydrochloric acid aqueous solution, 50% ethanol aqueous solution, 1,3-bis(2-trifluoromethyl-4- After 2 hours of reflux reaction of the mixture of nitrophenoxy)benzene and reduced iron powder, add 10% ammonia water, heat filter, cool the mother liquor in an ice-water bath, add 5% dilute hydrochloric acid solution, and precipitate 1,3-bis(2-tris Fluoromethyl-4-aminophenoxy)benzene dihydrochloride. Add ammonia water to the dihydrochloride of 1,3-bis(2-trifluoromethyl-4-aminophenoxy)benzene in dichloromethane solvent to separate out pure 1,3-bis(2-trifluoromethyl -4-aminophenoxy)benzene solid, melting point 41.2°C (DSC method, air atmosphere), yield 62%. But the disadvantages of this method are: (1) the three wastes are serious; (2) the yield is too low; (3) the prospect of industrialization is bleak.

Wonbong Jang, Ho-Seong Lee, Seokkyu Lee, Seunghyuk Choi, Daeyong Shin, Haksoo Han【The optical and dielectric characterization of light-colored fluorinated polyimides based on1，3-bis(4-amino-2-trifluoromethylphenoxy)benzene, Materials and Physics, 2007, 104:342-349] discloses the preparation method of 1,3-bis(2-trifluoromethyl-4-aminophenoxy)benzene, which is characterized in that: 1,3-bis(2- Trifluoromethyl-4-nitrophenoxy)benzene and ethanol/ethyl acetate (volume ratio 1:1) suspension of 10% palladium/carbon, stirred at room temperature for 30min, heated to 60°C to continue the reaction for 3 hours, Filtrate while hot, remove palladium/charcoal, distill and concentrate the mother liquor, vacuum dry at 80°C, and precipitate a solid product to obtain light yellow 1,3-bis(2-trifluoromethyl-4-aminophenoxy)benzene product (yield rate 88.5%), melting point 18 ℃ (DSC method, heating rate 5 ℃ / min). But the shortcoming of this method is: (1) product color is darker, and fusing point is also low, shows that purity is too low (1,3-bis(2-trifluoromethyl-4-aminophenoxy) benzene is white in nature) , cannot be directly used for polymerization, and further purification treatment is required; (2) the yield is too low; (3) according to the technical scheme described in the article, it has been proved by experiments that the target product cannot be reproduced, nor can it repeat the description of this technical scheme The technical effect may be omitted in this technical solution; (4) the prospect of industrialization is bleak.

Contents of the invention

The technical problem to be solved by the present invention is to provide a preparation method of 1,3-bis(2-trifluoromethyl-4-aminophenoxy)benzene, which has simple process, low cost, environmental friendliness, high purity and yield High rate, suitable for industrial production.

The chemical reaction equation of the present invention is as follows:

A kind of 1, the preparation method of 3-bis(2-trifluoromethyl-4-aminophenoxy)benzene of the present invention comprises:

Add 1,3-bis(2-trifluoromethyl-4-nitrophenoxy)benzene, organic solvent, and catalyst into the autoclave, feed hydrogen, stir, replace residual air, continue to feed hydrogen, and heat up to 40°C~80°C, maintain the pressure in the reactor at 0.4MPa~1.2MPa, keep the reaction for 2~5 hours, cool the reaction system to room temperature, slowly release the pressure, and blow nitrogen to replace all the residual hydrogen to ensure that the high pressure reactor In an inert atmosphere, filter, recover the filter residue (catalyst), keep the mother liquor, and add deionized water dropwise while stirring in the mother liquor, and precipitate a white solid product, filter, wash, and dry to obtain 1,3-bis(2-tris Fluoromethyl-4-aminophenoxy)benzene solid;

Wherein, the volume weight ratio of organic solvent and 1,3-bis(2-trifluoromethyl-4-nitrophenoxy)benzene is 5 milliliters～15 milliliters: 1 gram; Catalyst and 1,3-bis(2 - The weight ratio of trifluoromethyl-4-nitrophenoxy)benzene is 1:30-100; the volume ratio of deionized water and organic solvent must be strictly controlled within the range of 1:0.5-2.

The organic solvent is selected from one or more mixtures of methanol, ethanol, propanol, isopropanol, ethylene glycol, 1,2-propanediol and 1,3-propanediol;

Described catalyst is selected from Raney nickel or palladium/carbon;

The palladium/carbon has a metal palladium content of 1%-10% by mass.

In N,N-dimethylacetamide solvent, within the temperature range of 0°C to 10°C, the obtained 1,3-bis(2-trifluoromethyl-4-aminophenoxy)benzene solid was mixed with Equimolar pyromellitic dianhydride is reacted to obtain a highly viscous polyamic acid solution with an intrinsic viscosity as high as 2.0dL/g; the coating film is thermally imidized to obtain a tough and transparent polyimide film , the tensile strength is as high as 126MPa, and the glass transition temperature is 241.4°C.

Beneficial effect

(1) The preparation method of the present invention is simple to operate and has no special requirements for equipment; the reaction process is carried out under normal pressure, the source of raw materials is convenient, the cost is low, and neither involves nor produces corrosive substances (such as raw materials such as hydrazine hydrate); organic solvent There are few types of use, can be recycled repeatedly, and are friendly to the environment;

(2) The method does not require recrystallization operation, which simplifies the process, and the melting point of the product is 88.3°C, the yield is as high as 95%, and the purity is as high as 99.8%, which is suitable for industrial production.

Description of drawings

Fig. 1 is the molecular structure of 1,3-two (2-trifluoromethyl-4-aminophenoxy) benzene;

Fig. 2 is the differential scanning calorimeter (DSC) scanning pattern of 1,3-two (2-trifluoromethyl-4-aminophenoxy) benzene;

Fig. 3 is the Fourier Transform Infrared Spectrum FTIR spectrum of 1,3-two (2-trifluoromethyl-4-aminophenoxy) benzene;

Fig. 4 is a Fourier transform infrared spectrum FTIR spectrum of 1,3-bis(2-trifluoromethyl-4-aminophenoxy)benzene/pyromellitic dianhydride-polyimide film.

Detailed ways

Below in conjunction with specific embodiment, further illustrate the present invention. It should be understood that these examples are only used to illustrate the present invention and are not intended to limit the scope of the present invention. In addition, it should be understood that after reading the teachings of the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the appended claims of the present application.

Example 1

48.8 grams (0.10 moles) of 1,3-bis(2-trifluoromethyl-4-nitrophenoxy)benzene, 488 milliliters of methanol solvent, 0.8 grams of 10% palladium/carbon catalyst were added to the autoclave, and the Stir with hydrogen, replace the residual air, continue to flow hydrogen, heat up to 40°C-80°C, maintain the pressure in the reactor at 0.4MPa-1.2MPa, keep the reaction for 4.5 hours, cool the reaction system to room temperature, slowly release the pressure, and Nitrogen is passed to replace all residual hydrogen to ensure that the autoclave is an inert atmosphere, filter, reclaim the filter residue (catalyst), leave the mother liquor, and add 600 milliliters of deionized water dropwise while stirring in the mother liquor to separate out a white solid product. Filter, wash with deionized water for 2 to 3 times, and vacuum-dry at 25°C to obtain 40.6 grams (95%) of white 1,3-bis(2-trifluoromethyl-4-aminophenoxy) Benzene solid powder (theoretical output: 42.8 grams), purity 99.8%, melting point 88.3 ℃, (DSC method, nitrogen atmosphere, heating rate 10 ℃/min), as shown in Figure 2; Its Fourier transform infrared spectrogram is shown in Figure 3 Show.

In 30 ml of N,N-dimethylacetamide solvent, in the temperature range of 0°C to 10°C, the obtained 1,3-bis(2-trifluoromethyl-4-aminophenoxy)benzene 4.28 g (0.01 mol) of the solid was reacted with 2.18 g (0.01 mol) of pyromellitic dianhydride for 5 hours to obtain a highly viscous polyamic acid solution with an intrinsic viscosity of 2.0 dL/g. Evenly coat the above polyamic acid solution on a clean flat glass, put it into a blast oven, and heat imidize. The specific process is: start heating from room temperature to 80°C and keep it warm for 1 hour; continue to heat up to 140°C , heat preservation for 1 hour; continue to heat up to 220 ° C, heat preservation for 1 hour; continue to heat up to 280 ° C, heat preservation for 0.5 hours; naturally cool to room temperature, and release the film to obtain a tough and transparent polyimide film with a tensile strength of 126 MPa, glass The transition temperature is 241.4°C. The Fourier transform infrared spectrum of 1,3-bis(2-trifluoromethyl-4-aminophenoxy)benzene/pyromellitic dianhydride-polyimide film is shown in FIG. 4 .

Example 2

48.8 g (0.10 mol) of 1,3-bis(2-trifluoromethyl-4-nitrophenoxy)benzene, 500 ml of ethanol and 232 ml of methanol solvent, 1.2 g of 10% palladium on carbon catalyst were added to the high pressure Reactor, flow hydrogen, stir, replace the residual air, continue to pass hydrogen, heat up to 40 ° C ~ 80 ° C, maintain the pressure in the reaction kettle 0.4 MPa ~ 1.2 MPa, keep the reaction for 2 hours, cool the reaction system to room temperature, slowly Relieve the pressure, and pass nitrogen to replace all residual hydrogen, ensure that the autoclave is an inert atmosphere, filter, reclaim the filter residue (catalyst), leave the mother liquor, and add 366 milliliters of deionized water dropwise while stirring in the mother liquor, and precipitate The white solid product was filtered, washed 2 to 3 times with deionized water, and vacuum-dried at 25°C to obtain 39.4 grams (92%) of white 1,3-bis(2-trifluoromethyl-4-amino Phenoxy)benzene solid powder (theoretical yield: 42.8 g).

Example 3

48.8 grams (0.10 moles) of 1,3-bis(2-trifluoromethyl-4-nitrophenoxy)benzene, 200 milliliters of ethylene glycol and 44 milliliters of methanol solvent, 1.6 grams of 1% palladium/carbon catalyst were added In the high-pressure reaction kettle, let hydrogen flow, stir, replace the residual air, continue to flow hydrogen, heat up to 40 ° C ~ 80 ° C, maintain the pressure in the reaction kettle 0.4 MPa ~ 1.2 MPa, keep the reaction for 5 hours, cool the reaction system to room temperature, Slowly depressurize, and ventilate nitrogen to replace all residual hydrogen, ensure that in the autoclave it is an inert atmosphere, filter, reclaim the filter residue (catalyst), keep the mother liquor, and add 488 milliliters of deionized water dropwise while stirring in the mother liquor, A white solid product was precipitated, filtered, washed 2 to 3 times with deionized water, and dried under vacuum at 25°C to obtain 34.2 g (product yield: 80%) of white 1,3-bis(2-trifluoromethyl-4- Aminophenoxy)benzene solid powder (theoretical yield: 42.8 g).

Example 4

48.8 grams (0.10 moles) of 1,3-bis(2-trifluoromethyl-4-nitrophenoxy)benzene, 400 milliliters of ethanol solvent, 0.5 gram of 10% palladium/carbon catalyst were added to the autoclave, and the Stir with hydrogen, replace the residual air, continue to pass hydrogen, heat up to 40°C-80°C, maintain the pressure in the reactor at 0.4MPa-1.2MPa, keep the reaction for 4 hours, cool the reaction system to room temperature, slowly release the pressure, and Nitrogen is passed to replace all residual hydrogen to ensure that the autoclave is an inert atmosphere, filter, reclaim the filter residue (catalyst), leave the mother liquor, and add 500 milliliters of deionized water dropwise while stirring in the mother liquor to separate out a white solid product. Filter, wash with deionized water for 2 to 3 times, and vacuum-dry at 25°C to obtain 38.5 grams (90% product yield) of white 1,3-bis(2-trifluoromethyl-4-aminophenoxy) Benzene solid powder (theoretical yield: 42.8 g).

Example 5

48.8 grams (0.10 moles) of 1,3-bis(2-trifluoromethyl-4-nitrophenoxy)benzene, 500 milliliters of ethanol solvent, 1.0 grams of 5% palladium/carbon catalyst were added to the autoclave, and the Stir with hydrogen, replace the residual air, continue to flow hydrogen, heat up to 40°C-80°C, maintain the pressure in the reactor at 0.4MPa-1.2MPa, keep the reaction for 3 hours, cool the reaction system to room temperature, slowly release the pressure, and Nitrogen is passed to replace all residual hydrogen to ensure that the autoclave is an inert atmosphere, filter, reclaim the filter residue (catalyst), leave the mother liquor, and add 700 milliliters of deionized water dropwise while stirring in the mother liquor to separate out a white solid product. Filter, wash 2～3 times with deionized water, vacuum-dry at 25 ℃, obtain 39.8 grams (product yield is 93%) white 1,3-bis(2-trifluoromethyl-4-aminophenoxy) Benzene solid powder (theoretical yield: 42.8 g).

Claims (1)

1. one kind 1, the preparation method of two (2-trifluoromethyl-4-aminophenoxyl) benzene of 3-comprises:

With two (2-trifluoromethyl-4-nitrophenoxy) benzene of 48.8 grams, 1,3-, 488 ml methanol solvents, 0.8 restrain 10% Pd/carbon catalyst adding autoclave, logical hydrogen, stir, displace residual air, continue logical hydrogen, heat to 40 ℃ ~ 80 ℃, keep reacting kettle inner pressure 0.4MPa ~ 1.2MPa, keep reaction after 4.5 hours, cooling reaction system is to room temperature, slowly release, and logical nitrogen is to displace all remaining hydrogen, guarantee to be inert atmosphere in the autoclave, filter, reclaim filter residue, leave and take mother liquor, and in mother liquor, drip while stirring 600 ml deionized water, and separate out white solid product, filter, with deionized water wash 2 ~ 3 times, 25 ℃ of vacuum-dryings obtain 1 of 40.6 gram whites, two (2-trifluoromethyl-4-nitrophenoxy) benzene of 3-, purity 99.8%, 88.3 ℃ of fusing points.

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