Synthesis method of 2, 2-bis (4-carboxyphenyl) hexafluoropropane

Abstract

The invention discloses a synthesis method of 2, 2-bis (4-carboxyl phenyl) hexafluoropropane, which comprises the following steps: by taking bisphenol AF as a raw material, carrying out sulfonylation reaction to obtain a corresponding sulfonate compound, and then carrying out carbonyl insertion reaction to prepare the 2, 2-bis (4-carboxyl phenyl) hexafluoropropane. The synthesis method is simple and easy to operate, high in yield and high in product purity, and can be applied to actual industrial production.

Description

Technical Field

[0001] The present application relates to the technical field of fine organic synthesis, and particularly relates to a method for synthesizing 2,2-bis(4-carboxyphenyl)hexafluoropropane. Background Art

[0002] In the aspect of fluorine-containing materials, with the rapid development of industries such as integrated circuits, new energy, aerospace, and military in China, the demand for high-end fluorine-containing polymer varieties is increasing continuously. 2,2-bis(4-carboxyphenyl)hexafluoropropane, as a monomer of fluorine-containing polyester, has high development value.

[0003] Currently, the synthesis methods of 2,2-bis(4-carboxyphenyl)hexafluoropropane compounds are as follows: In the preparation method of 2,2-bis(4-carboxyphenyl)hexafluoropropane under a catalytic system in CN102516070B, 2,2-bis(4-methylphenyl)hexafluoropropane is used as a raw material, and a catalytic oxidation reaction is carried out in the presence of a catalyst, an oxidant, and a solvent. The reaction solution is processed to obtain 2,2-bis(4-carboxyphenyl)hexafluoropropane. The catalyst is N-hydroxyphthalimide and a transition metal salt, and the oxidant is oxygen. Cobalt acetate is used as a co-catalyst in this method. This compound will decompose at high temperatures, and in the presence of oxygen, oxygen can react with cobalt acetate to promote the decomposition of cobalt acetate, resulting in a further decrease in the decomposition temperature. After the co-catalyst decomposes and loses its catalytic effect, the production efficiency will be greatly reduced.

[0004] CN108358794A - A new method for synthesizing 2,2-bis(4-aminophenyl)hexafluoropropane. This method uses 2,2-bis(4-methylphenyl)hexafluoropropane as a raw material, oxidizes it with chromium trioxide to obtain 2,2-bis(4-carboxyphenyl)hexafluoropropane, then carries out an acyl chlorination reaction, and then introduces ammonia for an amidation reaction to obtain 2,2-bis(4-formamidophenyl)hexafluoropropane. Finally, a Hofmann degradation reaction occurs in a sodium hypochlorite solution to obtain the target product. Chromium trioxide is used as an oxidant in this method, and this compound is toxic and not suitable for industrial production.

[0005] Therefore, how to prepare a synthesis method of 2,2-bis(4-carboxyphenyl)hexafluoropropane with mild conditions and high yield is a technical problem that needs to be urgently solved by those skilled in the art. Summary of the Invention

[0006] To solve the single limitations of existing fluorine-containing materials, the present invention provides a method for synthesizing 2,2-bis(4-carboxyphenyl)hexafluoropropane. Using bisphenol AF as a raw material, the corresponding sulfonate compound is obtained through a sulfonylation reaction, and then 2,2-bis(4-carboxyphenyl)hexafluoropropane is prepared through a carbonylation reaction. This synthesis method has a simple process, mild reaction conditions, high selectivity, high product purity, simple post-treatment, and high yield, and is suitable for large-scale industrial production.

[0007] To achieve the above object, the present invention adopts the following technical solutions:

[0008] A method for synthesizing 2,2-bis(4-carboxyphenyl)hexafluoropropane, comprising the following steps:

[0009] (1) Dissolve bisphenol AF in a reaction solvent, then add an acid-binding agent, stir evenly and cool to a low temperature, slowly dropwise add a sulfonyl chloride reagent, and then raise the temperature and continuously stir for the sulfonylation reaction. After completion, wash with water and then recover the solvent by vacuum distillation to obtain a sulfonate compound;

[0010] (2) Dissolve the sulfonate compound, a palladium catalyst, and a ligand in a solvent and water, introduce carbon monoxide, raise the temperature for the carbonylation reaction. After the reaction is completed, cool to room temperature and normal pressure, neutralize with hydrochloric acid multiple times, and take the organic phase for recrystallization to obtain the target product.

[0011] Preferably, the sulfonyl chloride reagent is trifluoromethanesulfonyl chloride; the molar ratio of the sulfonyl chloride reagent to bisphenol AF is 2-3:1.

[0012] Preferably, the acid-binding agent is one or a combination of sodium hydroxide, sodium carbonate, potassium carbonate, sodium acetate, triethylamine, pyridine, etc.; the molar ratio of the acid-binding agent to bisphenol AF is 2-3:1.

[0013] Preferably, in step (1), the solvent is one or a combination of methanol, ethanol, isopropanol, butanol, ether, ethyl acetate, tetrahydrofuran, cyclohexane, n-heptane, petroleum ether, toluene, xylene, anisole, dioxane, etc.; after adding the acid-binding agent, cool to -10-5°C; the temperature of the sulfonylation reaction is 20-50°C, and the reaction time is 2-24h.

[0014] Preferably, the palladium catalyst is one or a combination of palladium dichloride, tetrakis(triphenylphosphine)palladium, bis(triphenylphosphine)palladium dichloride, palladium acetate, bis(triphenylphosphine)palladium acetate, 1,1'-bis(diphenylphosphino)ferrocene dichloride, palladium acetylacetonate, palladium trifluoroacetate, palladium trifluoromethanesulfonate, etc.; the mass of the palladium catalyst is 0.1-10% of the mass of bisphenol AF, more preferably (0.5-1)%.

[0015] Preferably, the ligand is a combination of one or more of triphenylphosphine, trimethylphosphine, triethylphosphine, tri-tert-butylphosphine, 1,1'-bis(diphenylphosphino)ferrocene, 1,2-bis(diphenylphosphino)ethane, 1,3-bis(diphenylphosphino)propane, 1,1'-binaphthyl-2,2'-bisdiphenylphosphine, tricyclohexylphosphine, 1,1'-binaphthol, 2-dicyclohexylphosphino-2',4',6'-triisopropylbiphenyl, and 2-dicyclohexylphosphino-2',6'-dimethoxybiphenyl; and the mass of the ligand is 1-10 times the mass of the palladium catalyst, more preferably 3-5 times.

[0016] Preferably, the solvent in step (2) is a combination of one or more of dichloromethane, dichloroethane, toluene, xylene, triethylamine, dimethylformamide, dimethylacetamide, and dimethyl sulfoxide; carbon monoxide is introduced to maintain the pressure of the reaction container at 1-3 MPa, the carbonylation reaction temperature is 0-200°C, more preferably 20-150°C, and the reaction time is 5-24h.

[0017] Preferably, in step (2), the organic phase is recrystallized in ethanol-water.

[0018] The reaction process of the present invention is:

[0019]

[0020] Beneficial effects of the present invention:

[0021] The present invention provides a method for synthesizing 2,2-bis(4-carboxyphenyl)hexafluoropropane:

[0022] 1. Using bisphenol AF as a raw material, under low temperature conditions, selecting a suitable range of reactant dosage, and obtaining the corresponding sulfonate compound through sulfonylation reaction, while meeting the reaction requirements and saving costs, the sulfonate compound has higher stability and is convenient for transfer and use during the synthesis process.

[0023] 2. Use carbonyl insertion reaction to prepare 2,2-bis(4-carboxyphenyl)hexafluoropropane, and select a catalytic combination system of palladium catalyst combined with phosphine ligand to achieve high activity and high selectivity of the reaction. DETAILED DESCRIPTION

[0024] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] Embodiment 1:

[0026] (1) Bisphenol AF (33.6 g, 0.1 mol), sodium carbonate (21.2 g, 0.2 mol), and toluene (500 mL) were added to a 1 L three-necked flask, stirred evenly, cooled to 5 °C, and then trifluoromethanesulfonyl chloride (33.7 g, 0.2 mol) was slowly added dropwise. After the addition was completed, the temperature was raised to 20 °C and stirred for reaction for 10 h. After the reaction was completed, it was cooled, washed with water until the organic phase was neutral, the aqueous phase was separated, and the organic phase was distilled under reduced pressure to recover the solvent, obtaining a sulfonate compound;

[0027] (2) The sulfonate compound obtained in step (1), palladium dichloride (0.03 g), and triphenylphosphine (0.09 g) were added to a 500 mL three-necked flask. The flask was evacuated and replaced with nitrogen three times, and then toluene (150 mL) and water (50 mL) were added and stirred evenly. Carbon monoxide (3 MPa) was continuously introduced into the flask, and the reaction was carried out at 20 °C for 24 h. After the reaction was completed, the mixture was cooled to room temperature and atmospheric pressure. 2M hydrochloric acid (150 mL) was added to the mixture, and after repeating 3 times, it was allowed to stand. The organic phase was recrystallized from ethanol-water to obtain 35.2 g of white solid 2,2-bis(4-carboxyphenyl)hexafluoropropane, with a yield of 89.7%.

[0028] Example 2:

[0029] (1) Bisphenol AF (33.6 g, 0.1 mol), potassium carbonate (41.4 g, 0.3 mol), and dichloromethane (500 mL) were added to a 1 L three-necked flask, stirred evenly, cooled to -10 °C, and then trifluoromethanesulfonyl chloride (50.6 g, 0.3 mol) was slowly added dropwise. After the addition was completed, the temperature was raised to 50 °C and stirred for reaction for 5 h. After the reaction was completed, it was cooled, washed with water until the organic phase was neutral, the aqueous phase was separated, and the organic phase was distilled under reduced pressure to recover the solvent, obtaining a sulfonate compound;

[0030] (2) The sulfonate compound obtained in step (1), bis(triphenylphosphine)palladium dichloride (0.17 g), and 1,1'-bis(diphenylphosphino)ferrocene (0.68 g) were added to a 500 mL three-necked flask. The flask was evacuated and replaced with nitrogen three times, and then dimethylacetamide (150 mL) and water (50 mL) were added and stirred evenly. Carbon monoxide (3 MPa) was continuously introduced into the flask, and the reaction was carried out at 150 °C for 5 h. After the reaction was completed, the mixture was cooled to room temperature and atmospheric pressure. 2M hydrochloric acid (150 mL) was added to the mixture, and after repeating 3 times, it was allowed to stand. The organic phase was recrystallized from ethanol-water to obtain 37.1 g of white solid 2,2-bis(4-carboxyphenyl)hexafluoropropane, with a yield of 94.6%.

[0031] Example 3:

[0032] (1) Add bisphenol AF (33.6 g, 0.1 mol), sodium carbonate (21.2 g, 0.2 mol), and tetrahydrofuran (500 mL) into a 1 L three-necked flask, stir evenly, cool to 0° C., and slowly drop trifluoromethanesulfonyl chloride (50.6 g, 0.3 mol). After the dropwise addition is completed, heat to 30° C. and stir to react for 8 h. After the reaction is completed, cool and wash with water until the organic phase is neutral. Separate the aqueous phase, and distill the organic phase under reduced pressure to recover the solvent to obtain a sulfonate compound;

[0033] (2) Add the sulfonate compound obtained in step (1), palladium acetate (0.34 g), and tri-tert-butylphosphine (1.70 g) to a 500 mL three-necked flask, evacuate the flask, replace it with nitrogen three times, then add dimethyl sulfoxide (150 mL) and water (50 mL), and stir evenly. Continue to pass carbon monoxide (3 MPa) into the flask, keep the temperature at 100 ° C for 8 hours, and after the reaction is completed, cool the mixed solution to room temperature and normal pressure. Add 2M hydrochloric acid (150 mL) to the mixed solution, repeat 3 times and let it stand, take the organic phase and recrystallize it in ethanol-water to obtain 36.5 g of white solid 2,2-bis(4-carboxyphenyl)hexafluoropropane, with a yield of 93.1%.

[0034] Embodiment 4:

[0035] The same experimental apparatus and conditions as in Example 1 were adopted, except that "sodium carbonate (21.2 g, 0.2 mol)" in step (1) was replaced with "triethylamine (20.2 g, 0.2 mol)", and "toluene (500 mL)" was replaced with "ethanol (500 mL)" to obtain 36.1 g of white solid 2,2-bis(4-carboxyphenyl)hexafluoropropane, with a yield of 92.0%.

[0036] Embodiment 5:

[0037] The same experimental apparatus and conditions as in Example 1 were adopted, except that "sodium carbonate (21.2 g, 0.2 mol)" in step (1) was replaced with "sodium acetate (16.4 g, 0.2 mol)" to obtain 34.9 g of white solid 2,2-bis(4-carboxyphenyl)hexafluoropropane with a yield of 89.0%.

[0038] Embodiment 6:

[0039] The same experimental apparatus and conditions as in Example 1 were adopted, except that the “dichloropalladium (0.03 g) and triphenylphosphine (0.09 g)” in step (2) were replaced with “tetrakistriphenylphosphine palladium (0.03 g) and triethylphosphine (0.09 g)” to obtain 35.4 g of white solid 2,2-bis(4-carboxyphenyl)hexafluoropropane with a yield of 90.2%.

[0040] Embodiment 7:

[0041] Using the same experimental apparatus and conditions as in Example 1, change "palladium dichloride (0.03 g), triphenylphosphine (0.09 g)" in step (2) to "palladium trifluoroacetate (0.03 g), 1,3-bis(diphenylphosphino)propane (0.09 g)", and 34.6 g of white solid 2,2-bis(4-carboxyphenyl)hexafluoropropane is obtained, with a yield of 88.2%.

[0042] Example 8:

[0043] Using the same experimental apparatus and conditions as in Example 1, change "palladium dichloride (0.03 g), triphenylphosphine (0.09 g)" in step (2) to "palladium trifluoromethanesulfonate (0.03 g), 2-dicyclohexylphosphino-2',6'-dimethoxybiphenyl (0.09 g)", and 34.0 g of white solid 2,2-bis(4-carboxyphenyl)hexafluoropropane is obtained, with a yield of 86.7%.

[0044] Example 9:

[0045] Using the same experimental apparatus and conditions as in Example 1, change "continuously introduce carbon monoxide (3 MPa) into the flask" in step (2) to "continuously introduce carbon monoxide (1 MPa) into the flask", and 35.7 g of white solid 2,2-bis(4-carboxyphenyl)hexafluoropropane is obtained, with a yield of 91.0%.

[0046] Example 10:

[0047] Using the same experimental apparatus and conditions as in Example 1, change "continuously introduce carbon monoxide (3 MPa) into the flask and react at 20 °C for 24 h" in step (2) to "continuously introduce carbon monoxide (0.5 MPa) into the flask and react at 100 °C for 12 h", and 34.8 g of white solid 2,2-bis(4-carboxyphenyl)hexafluoropropane is obtained, with a yield of 88.7%.

[0048] Comparative Example 1:

[0049] Using the same experimental apparatus and conditions as in Example 1, change "sodium carbonate (21.2 g, 0.2 mol)" in step (1) to "sodium carbonate (10.6 g, 0.1 mol)", and 15.6 g of white solid 2,2-bis(4-carboxyphenyl)hexafluoropropane is obtained, with a yield of 39.8%.

[0050] Comparative Example 2:

[0051] Using the same experimental apparatus and conditions as in Example 1, change "trifluoromethanesulfonyl chloride (33.7 g, 0.2 mol)" in step (1) to "trifluoromethanesulfonyl chloride (16.8 g, 0.1 mol)", and 13.7 g of white solid 2,2-bis(4-carboxyphenyl)hexafluoropropane is obtained, with a yield of 34.9%.

[0052] Comparative Example 3:

[0053] Using the same experimental apparatus and conditions as in Example 1, change "palladium dichloride (0.03 g)" in step (2) to "palladium dichloride (0.01 g)", and 17.1 g of white solid 2,2-bis(4-carboxyphenyl)hexafluoropropane is obtained, with a yield of 43.6%.

[0054] Comparative Example 4:

[0055] Using the same experimental apparatus and conditions as in Example 1, change "triphenylphosphine (0.09 g)" in step (2) to "triphenylphosphine (0.03 g)", and 15.9 g of white solid 2,2-bis(4-carboxyphenyl)hexafluoropropane is obtained, with a yield of 40.5%.

[0056] Comparative Example 5:

[0057] Using the same experimental apparatus and conditions as in Example 1, change "continuously introduce carbon monoxide (3 MPa) into the flask" in step (2) to "continuously introduce carbon monoxide (0.1 MPa) into the flask", and 10.2 g of white solid 2,2-bis(4-carboxyphenyl)hexafluoropropane is obtained, with a yield of 26.0%.

[0058] In this specification, each embodiment is described in a progressive manner. Each embodiment focuses on the differences from other embodiments. For the same or similar parts among the embodiments, reference can be made to each other.

[0059] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be obvious to those skilled in the art. The general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for synthesizing 2,2-bis(4-carboxyphenyl)hexafluoropropane, characterized in that, The following steps are involved: (1) dissolving bisphenol AF in a reaction solvent, adding an acid binding agent, stirring and cooling to a low temperature, slowly dropping a sulfonyl chloride reagent, then heating and stirring continuously to carry out a sulfonylation reaction, and after completion, washing with water and then distilling under reduced pressure to recover the solvent to obtain a sulfonate compound; (2) Dissolve the sulfonate compound, palladium catalyst and ligand in a solvent and water, introduce carbon monoxide, and heat to carry out carbonyl insertion reaction. After the reaction is completed, cool to room temperature and normal pressure, neutralize with hydrochloric acid several times, and take the organic phase for recrystallization to obtain the target product.

2. The synthesis method of 2,2-bis(4-carboxyphenyl)hexafluoropropane according to claim 1, characterized in that, The sulfonyl chloride reagent is trifluoromethanesulfonyl chloride; the molar ratio of the sulfonyl chloride reagent to bisphenol AF is 2-3:

1.

3. The synthesis method of 2,2-bis(4-carboxyphenyl)hexafluoropropane according to claim 2, characterized in that, The acid-binding agent is one or a combination of sodium hydroxide, sodium carbonate, potassium carbonate, sodium acetate, triethylamine, and pyridine; the molar ratio of the acid-binding agent to bisphenol AF is 2-3:

1.

4. The synthesis method of 2,2-bis(4-carboxyphenyl)hexafluoropropane according to claim 1, characterized in that, In step (1), the solvent is one or more of methanol, ethanol, isopropanol, butanol, ether, ethyl acetate, tetrahydrofuran, cyclohexane, n-heptane, petroleum ether, toluene, xylene, anisole, and dioxane; after adding the acid binding agent, the temperature is lowered to -10-5°C; the temperature of the sulfonylation reaction is 20-50°C, and the reaction time is 2-24h.

5. The synthesis method of 2,2-bis(4-carboxyphenyl)hexafluoropropane according to claim 1, wherein, The palladium catalyst is a combination of one or more of palladium dichloride, tetrakistriphenylphosphine palladium, bis(triphenylphosphine)palladium dichloride, palladium acetate, bis(triphenylphosphine)palladium acetate, 1,1'-bisdiphenylphosphinoferrocenepalladium dichloride, palladium acetylacetonate, palladium trifluoroacetate, and palladium trifluoromethanesulfonate; the mass of the palladium catalyst is 0.1-10% of the mass of bisphenol AF.

6. The synthesis method of 2,2-bis(4-carboxyphenyl)hexafluoropropane according to claim 1, characterized in that, The ligand is a combination of one or more of triphenylphosphine, trimethylphosphine, triethylphosphine, tri-tert-butylphosphine, 1,1'-bis(diphenylphosphino)ferrocene, 1,2-bis(diphenylphosphino)ethane, 1,3-bis(diphenylphosphino)propane, 1,1'-binaphthyl-2,2'-bisdiphenylphosphine, tricyclohexylphosphine, 1,1'-binaphthol, 2-dicyclohexylphosphino-2',4',6'-triisopropylbiphenyl, and 2-dicyclohexylphosphino-2',6'-dimethoxybiphenyl; and the mass of the ligand is 1-10 times the mass of the palladium catalyst.

7. The synthesis method of 2,2-bis(4-carboxyphenyl)hexafluoropropane according to claim 1, characterized in that, The solvent in step (2) is a combination of one or more of dichloromethane, dichloroethane, toluene, xylene, triethylamine, dimethylformamide, dimethylacetamide, and dimethyl sulfoxide; carbon monoxide is introduced to maintain the pressure of the reaction container at 1-3 MPa, the carbonylation reaction temperature is 0-200° C., and the reaction time is 5-24 h.

8. A method for synthesizing 2,2-bis(4-carboxyphenyl)hexafluoropropane according to claim 1, characterized in that, In step (2), the organic phase is recrystallized in ethanol-water.

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