A process for the preparation of 2,2-bis[3-(3-aminobenzamido)-4-hydroxyphenyl]hexafluoropropane

Abstract

The application provides a preparation method of 2,2-bis[3-(3-aminobenzoylamino)-4-hydroxyphenyl]hexafluoropropane, which comprises the following steps: S1: m-aminobenzoic acid is added into a solvent, heated, a protective agent, a catalyst and 2,2-bis3-amino-4-hydroxyphenyl hexafluoropropane are added, after the reaction is completed, vacuum distillation is carried out to obtain a solution; S2: an acid solution is added into the solution in step S1, after the reaction is carried out by heating, cooling and stirring, filtration is carried out; the filter cake is dissolved in a solvent, activated carbon and silica gel are added into the filtrate, a magnetic filter is used for filtration, the solvent in the filtrate is evaporated, cooling is carried out, and 2,2-bis[3-(3-aminobenzoylamino)-4-hydroxyphenyl]hexafluoropropane is obtained by filtration. The application has the beneficial effects that the process operation is simple, the finished product quality is good, the yield is high, and the application can be used for large-scale production.

Description

A method for preparing 2,2-bis[3-(3-aminobenzoylamino)-4-hydroxyphenyl]hexafluoropropane Technical Field

[0001] This invention belongs to the field of organic synthesis technology, and in particular relates to a method for preparing 2,2-bis[3-(3-aminobenzoylamino)-4-hydroxyphenyl]hexafluoropropane. Background Technology

[0002] 2,2-Bis[3-(3-aminobenzoylamino)-4-hydroxyphenyl]hexafluoropropane is used to prepare photosensitive polyimide (PSPI). PSPI is a high-end polyimide, an organic material with both imine rings and photosensitive groups on its polymer chain. PSPI has excellent photosensitivity, good thermal stability, and good mechanical properties. In the aerospace field, PSPI can be used as a thermal insulation material for aircraft; in the microelectronics field, PSPI can be used as an electronic encapsulant; in the OLED display field, PSPI can be used as a photoresist for OLED displays, effectively reducing color difference in OLED display devices and improving their interlayer insulation.

[0003] Currently, patents CN109328322A and CN109563353B disclose common methods for preparing 2,2-bis[3-(3-aminobenzoylamino)-4-hydroxyphenyl]hexafluoropropane, mainly a two-step method: Step 1: Using 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane (6FAP) and p-nitrobenzoyl chloride as raw materials, a low-temperature reaction in a mixed solvent yields the intermediate dinitro compound: 2,2-bis[3-(3-nitrobenzoylamino)-4-hydroxyphenyl]hexafluoropropane. Step 2: The intermediate dinitro compound is reduced to 2,2-bis[3-(3-aminobenzoylamino)-4-hydroxyphenyl]hexafluoropropane via palladium on carbon hydrogenation or hydrazine hydrate. The mixed solvent used in this method is relatively cumbersome to recycle. Secondly, the second reduction reaction uses palladium on carbon, hydrogen, and hydrazine hydrate reduction. However, existing hydrogenation reduction processes are classified as hazardous and subject to regulatory oversight, thus limiting mass production. Existing processes have certain drawbacks; this invention employs a one-pot method to avoid these shortcomings while also enabling mass production. Summary of the Invention

[0004] In view of this, the present invention aims to propose a one-pot method for preparing 2,2-bis[3-(3-aminobenzoylamino)-4-hydroxyphenyl]hexafluoropropane, which is simple in process, has good product quality, high yield, and is suitable for large-scale production.

[0005] To achieve the above objectives, the technical solution of the present invention is implemented as follows:

[0006] A method for preparing 2,2-bis[3-(3-aminobenzoylamino)-4-hydroxyphenyl]hexafluoropropane includes the following steps:

[0007] S1: Add m-aminobenzoic acid to the solvent, heat, add protective agent, catalyst, and 2,2-bis3-amino-4-hydroxyphenyl hexafluoropropane, and after the reaction is complete, distill under reduced pressure to obtain a solution;

[0008] S2: Add an acidic solution to the solution in step S1, heat the reaction, cool down, stir and filter; the filter cake dissolves in the solvent, add activated carbon, silica gel and magnetic filter to the filtrate, filter, evaporate the solvent from the filtrate, cool down and filter to obtain 2,2-bis[3-(3-aminobenzoylamino)-4-hydroxyphenyl]hexafluoropropane.

[0009] Furthermore, the catalyst in step S1 includes one or more of the following: dicyclohexylcarbodiimide, diisopropylcarbodiimide, 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide, 1,5,7-triazidobicyclo(4,4,0)dec-5-ene, 2-ethoxy-1-ethoxycarbonyl-1,2-dihydroquinoline, N,N'-carbonyldiimidazole, isobutyl 1,2-dihydro-2-isobutoxyquinoline-1-carboxylate, N-heptafluorobutyrylimidazole, and pentafluoropropionylimidazole.

[0010] Preferably, the catalyst is N-heptafluorobutyrylimidazol.

[0011] Furthermore, the solvent in step S1 includes one or more of acetonitrile, chloroform, N,N-dimethylacetamide, tetrahydrofuran, methyltetrahydrofuran, N,N-dimethylformamide, dimethyl sulfoxide, N-methylpyrrolidone, dioxane, methanol, isopropanol, ethyl acetate, acetone, and isoamyl acetate. Preferably, the solvent is N-methyltetrahydrofuran.

[0012] Furthermore, the reaction temperature in step S1 is 40-110°C, preferably 85°C.

[0013] Furthermore, the protective agent in step S1 includes one or more of acetic anhydride, chloroformate, propionic anhydride, and di-tert-butyl dicarbonate, preferably di-tert-butyl dicarbonate.

[0014] Furthermore, the acidic solution in step S1 includes one or more of trifluoroacetic acid, trichloroacetic acid, hydrochloric acid, oxalic acid, citric acid, and phosphoric acid; preferably, citric acid.

[0015] Furthermore, the molar ratio of m-aminobenzoic acid, protective agent, catalyst, solvent, 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane, and acidic solution is 1:(2-2.5):(2-3):(10-20):(0.4-1):(1-7), preferably 1:2.2:2.5:15:0.5:3.2.

[0016] After adding the acid solution, react at a certain temperature for 3-5 hours, then cool down to below 10°C, stir for 1-3 hours, and then filter.

[0017] The stirring temperature after addition is 30-60℃, preferably 50℃.

[0018] Furthermore, the solvent in step S2 is electronic-grade methanol, and the weight of electronic-grade methanol added is 20-60 times that of m-aminobenzoic acid, preferably 30 times.

[0019] The filtrate was filtered at 40℃ in the following order: activated carbon, silica gel, magnetic filter, and precision filter.

[0020] Furthermore, in step S2, the solvent is evaporated from the filtrate, the temperature is lowered, and the solution is filtered to obtain 2,2-bis[3-(3-aminobenzoylamino)-4-hydroxyphenyl]hexafluoropropane. The cooling temperature is below 0°C.

[0021] A method for preparing 2,2-bis[3-(3-aminobenzoylamino)-4-hydroxyphenyl]hexafluoropropane includes the following steps:

[0022] m-Aminobenzoic acid was added to a solvent, and a protective agent was added under heating conditions, followed by a catalyst. The reaction was continued under heating conditions, and then 6FAP was added. After the reaction was complete, the solution was distilled under reduced pressure, and half of the solution was removed. Then, a 30% citric acid aqueous solution was added, and the reaction was carried out at a certain temperature for 4 hours. After that, the temperature was lowered to below 10°C, and the mixture was stirred for 2 hours before filtration. The filter cake was dissolved in electronic grade methanol, and the filtrate was filtered at 40°C in the following order: activated carbon, silica gel, magnetic filter, and precision filter. 80% of the methanol was removed from the filtrate. The solution was then cooled and filtered to obtain the final product.

[0023]

[0024] Compared with the prior art, the preparation method of 2,2-bis[3-(3-aminobenzoylamino)-4-hydroxyphenyl]hexafluoropropane described in this invention has the following advantages:

[0025] The preparation method described in this invention uses a one-pot process, which is simple, safe, and free of special reactions. The product has good quality, high yield, and the route is suitable for large-scale production. Attached Figure Description

[0026] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0027] Figure 1. HPLC schematic diagram of 2,2-bis[3-(3-aminobenzoylamino)-4-hydroxyphenyl]hexafluoropropane prepared in Example 1.

[0028] Figure 2. Schematic diagram of ICP-MS analysis of 2,2-bis[3-(3-aminobenzoylamino)-4-hydroxyphenyl]hexafluoropropane prepared in Example 1 using an Agilent 7900.

[0029] Figure 3 is a schematic diagram of the appearance of 2,2-bis[3-(3-aminobenzoylamino)-4-hydroxyphenyl]hexafluoropropane prepared in Example 1. Detailed Implementation

[0030] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0031] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0032] Example 1

[0033] 137g of m-aminobenzoic acid was added to 1300g of 2-methyltetrahydrofuran. 480g of ditert-butyl dicarbonate was added under heating conditions, followed by 660g of N-heptafluorobutyrylimidazol. The reaction was carried out at 85℃, followed by the addition of 183g of 6FAP. After the reaction was complete, the mixture was distilled under reduced pressure. After distilling off half of the solution, 2055g of 30% citric acid aqueous solution was added and stirred at 50℃ for 4 hours. The mixture was then cooled to below 10℃ with ice water and stirred for 2 hours before filtration. The filter cake was dissolved in 5480g of electronic-grade methanol. The filtrate was heated to 40℃ and filtered sequentially through activated carbon, silica gel, a magnetic filter, and a precision filter. After collecting the filtrate, 70% methanol was distilled off. The filtrate was cooled to 0℃, filtered, and vacuum dried to obtain 285g of the product 2,2-bis[3-(3-aminobenzoylamino)-4-hydroxyphenyl]hexafluoropropane, with a yield of 94.37%. The liquid phase content is 99.54% (see Figure 1), the number of individual metal ions is less than 500 ppb (see Figure 2), the appearance is a white powder (see Figure 3), and the yellow index YI is 1.32.

[0034] Example 2

[0035] 137g of m-aminobenzoic acid was added to 1720g of 2-methyltetrahydrofuran. 545g of di-tert-butyl dicarbonate was added under heating conditions, followed by 792g of N-heptafluorobutyrylimidazol. The reaction was carried out at 85℃, followed by the addition of 183g of 6FAP. After the reaction was complete, the mixture was distilled under reduced pressure. After distilling off half of the solution, 4110g of 30% citric acid aqueous solution was added and stirred at 50℃ for 4 hours. The mixture was then cooled to below 10℃ with ice water and stirred for 2 hours before filtration. The filter cake was dissolved in 8220g of electronic-grade methanol. The filtrate was heated to 40℃ and filtered sequentially through activated carbon, silica gel, a magnetic filter, and a precision filter. After collecting the filtrate, 70% methanol was distilled off. The filtrate was cooled to 0℃, filtered, and vacuum dried to obtain 287g of the product 2,2-bis[3-(3-aminobenzoylamino)-4-hydroxyphenyl]hexafluoropropane, with a yield of 95.03%. The liquid phase content is 99.55%, and the number of individual metal ions is less than 500 ppb. The appearance is a white powder with a yellow index YI of 2.36.

[0036] Example 3

[0037] 137g of m-aminobenzoic acid was added to 860g of 2-methyltetrahydrofuran. 436g of di-tert-butyl dicarbonate was added under heating conditions, followed by 528g of N-heptafluorobutyrylimidazol. The reaction was carried out at 85℃, followed by the addition of 183g of 6FAP. After the reaction was complete, the mixture was distilled under reduced pressure. After distilling off half of the solution, 1370g of 30% citric acid aqueous solution was added and stirred at 50℃ for 4 hours. The mixture was then cooled to below 10℃ with ice water and stirred for 2 hours before filtration. The filter cake was dissolved in 4110g of electronic-grade methanol. The filtrate was heated to 40℃ and filtered sequentially through activated carbon, silica gel, a magnetic filter, and a precision filter. After collecting the filtrate, 70% methanol was distilled off. The filtrate was cooled to 0℃, filtered, and vacuum dried to obtain 203g of the final product, 2,2-bis[3-(3-aminobenzoylamino)-4-hydroxyphenyl]hexafluoropropane, with a yield of 67.2%. Liquid phase content 99.43%, single metal ion less than 500 ppb, appearance: white powder, yellow index YI: 2.36.

[0038] Example 4

[0039] 137g of m-aminobenzoic acid was added to 1300g of 2-methyltetrahydrofuran. 176g of chloroformate was added under heating conditions, followed by 405g of N,N'-carbonyldiimidazole. The reaction was carried out at 85℃, and then 183g of 6FAP was added. After the reaction was complete, the mixture was distilled under reduced pressure. After distilling off half of the solution, 2000g of 30% citric acid aqueous solution was added and stirred at 50℃ for 4 hours. The mixture was then cooled to below 10℃ with ice water and stirred for 2 hours before filtration. The filter cake was dissolved in 5300g of electronic-grade methanol. The filtrate was heated to 40℃ and filtered sequentially through activated carbon, silica gel, a magnetic filter, and a precision filter. After collecting the filtrate, 70% methanol was distilled off. The filtrate was cooled to 0℃, filtered, and vacuum dried to obtain 196g of the product 2,2-bis[3-(3-aminobenzoylamino)-4-hydroxyphenyl]hexafluoropropane, with a yield of 64.9%. Liquid content 97.25%, single metal ion less than 1 ppm, appearance: off-white powder, yellow index YI: 3.69.

[0040] Example 5

[0041] 137g of m-aminobenzoic acid was added to 1320g of dioxane, followed by 480g of di-tert-butyl dicarbonate under heating conditions, and then 617g of 2-ethoxy-1-ethoxycarbonyl-1,2-dihydroquinoline. The reaction was carried out at 85℃, followed by the addition of 183g of 6FAP. After the reaction was complete, the mixture was distilled under reduced pressure, and half of the solution was removed. Then, 2500g of 30% citric acid aqueous solution was added and stirred at 50℃ for 4 hours. The mixture was then cooled to below 10℃ with ice water and stirred for 2 hours before filtration. The filter cake was dissolved in 5500g of electronic grade methanol. The filtrate was heated to 40℃ and filtered sequentially through activated carbon, silica gel, magnetic filter, and precision filter. After collecting the filtrate, 70% methanol was distilled off, and the mixture was cooled to 0℃, filtered, and vacuum dried to obtain 102g of the product 2,2-bis[3-(3-aminobenzoylamino)-4-hydroxyphenyl]hexafluoropropane, with a yield of 33.77%. The liquid phase content is 95.13%, the single metal ion is greater than 1 ppm, the appearance is light yellow powder, and the yellow index YI is 15.68.

[0042] Example 6

[0043] 137g of m-aminobenzoic acid was added to 1300g of 2-methyltetrahydrofuran. 480g of ditert-butyl dicarbonate was added under heating conditions, followed by 660g of N-heptafluorobutyrylimidazol. The reaction was carried out at 85℃, followed by the addition of 183g of 6FAP. After the reaction was complete, the mixture was distilled under reduced pressure. After distilling off half of the solution, 342g of trifluoroacetic acid solution was added and stirred at 60℃ for 4 hours. Then, 60% of the solvent was distilled off under reduced pressure. The mixture was cooled to below 10℃ and stirred for 2 hours before filtration. The filter cake was dissolved in 3000g of electronic-grade methanol. The filtrate was heated to 40℃ and filtered sequentially through activated carbon, silica gel, a magnetic filter, and a precision filter. After collecting the filtrate, 70% of the methanol was distilled off. The filtrate was cooled to 0℃, filtered, and vacuum dried to obtain 135g of the product 2,2-bis[3-(3-aminobenzoylamino)-4-hydroxyphenyl]hexafluoropropane, with a yield of 44.41%. The liquid phase content is 92.35%, the single metal ion is greater than 1 ppm, the appearance is off-white powder, and the yellow index YI is 13.51.

[0044] Example 7

[0045] 137g of m-aminobenzoic acid was added to 1300g of 2-methyltetrahydrofuran. 480g of ditert-butyl dicarbonate was added under heating conditions, followed by 660g of N-heptafluorobutyrylimidazol. The reaction was carried out at 85℃, followed by the addition of 183g of 6FAP. After the reaction was complete, the mixture was distilled under reduced pressure. After distilling off half of the solution, 2055g of trifluoroacetic acid was added and stirred at 50℃ for 4 hours. Then, 60% of the solvent was distilled off under reduced pressure. The mixture was cooled to below 10℃ and stirred for 2 hours before filtration. The filter cake was dissolved in 3500g of electronic-grade methanol. The filtrate was heated to 40℃ and filtered sequentially through activated carbon, silica gel, a magnetic filter, and a precision filter. After collecting the filtrate, 70% of the methanol was distilled off. The filtrate was cooled to 0℃, filtered, and vacuum dried to obtain 106g of the product 2,2-bis[3-(3-aminobenzoylamino)-4-hydroxyphenyl]hexafluoropropane, with a yield of 35.1%. The liquid phase content is 90.18%, the single metal ion is greater than 1 ppm, the appearance is off-white powder, and the yellow index YI is 10.12.

[0046] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for preparing 2,2-bis[3-(3-aminobenzoylamino)-4-hydroxyphenyl]hexafluoropropane, characterized in that: The steps include: S1: Add m-aminobenzoic acid to the solvent, heat, add a protective agent, a catalyst, and 2,2-bis3-amino-4-hydroxyphenyl hexafluoropropane, and after the reaction is complete, distill under reduced pressure to obtain a solution; S2: Add an acidic aqueous solution to the solution in step S1, heat the reaction, then cool, stir, and filter. The filter cake dissolves in the solvent, and the filtrate is filtered at 40°C in the following order: activated carbon, silica gel, magnetic filter, and precision filter. The solvent is evaporated from the filtrate, the temperature is lowered, and the filtrate is filtered to obtain 2,2-bis[3-(3-aminobenzoylamino)-4-hydroxyphenyl]hexafluoropropane. The protective agent in step S1 is di-tert-butyl dicarbonate. The acidic aqueous solution in step S2 is citric acid with a concentration of 30%. The catalyst in step S1 is N-heptafluorobutyrylimidazolium. The solvent in step S1 is 2-methyltetrahydrofuran. The reaction temperature in step S1 is 85°C. The molar ratio of m-aminobenzoic acid, protective agent, catalyst, 2-methyltetrahydrofuran, 2,2-bis3-amino-4-hydroxyphenylhexafluoropropane, and acidic aqueous solution is 1:2.2:2.5:15:0.5:3.

2. The solvent in step S2 is electronic-grade methanol.

2. The method for preparing 2,2-bis[3-(3-aminobenzoylamino)-4-hydroxyphenyl]hexafluoropropane according to claim 1, characterized in that: In step S2, add an acidic aqueous solution and react at a certain temperature for 3-5 hours. Then cool down to below 10°C, stir for 1-3 hours, and then filter.

3. The method for preparing 2,2-bis[3-(3-aminobenzoylamino)-4-hydroxyphenyl]hexafluoropropane according to claim 1, characterized in that: The stirring temperature after adding the acidic aqueous solution in step S2 is 30-60℃.

4. The method for preparing 2,2-bis[3-(3-aminobenzoylamino)-4-hydroxyphenyl]hexafluoropropane according to claim 3, characterized in that: The stirring temperature after adding the acidic aqueous solution in step S2 is 50°C.

5. The method for preparing 2,2-bis[3-(3-aminobenzoylamino)-4-hydroxyphenyl]hexafluoropropane according to claim 1, characterized in that: In step S2, the weight of electronic-grade methanol added is 30 times that of m-aminobenzoic acid.

6. The method for preparing 2,2-bis[3-(3-aminobenzoylamino)-4-hydroxyphenyl]hexafluoropropane according to claim 1, characterized in that: In step S2, the solvent is evaporated from the filtrate, the temperature is lowered, and the solution is filtered to obtain 2,2-bis[3-(3-aminobenzoylamino)-4-hydroxyphenyl]hexafluoropropane. The cooling temperature is below 0°C.

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