A method for synthesizing tetrafluoroethane fluorine-containing material

Abstract

The application relates to a synthesis method of tetrafluoroethane fluorine-containing material and belongs to the technical field of organic synthesis. In an inert gas atmosphere, a substrate is reacted with a ligand in a solvent, iron catalyst and Grignard reagent are sequentially added after cooling, and the mixture is stirred to obtain product 1; a mixed solution of tetrahydrofuran and hydrochloric acid is added to product 1 to carry out a hydrolysis reaction, and product 2 is obtained; an alcohol solution of product 2 is added with a reducing agent or an oxidizing agent to stir, and the tetrafluoroethane fluorine-containing material is obtained. The application overcomes the shortcomings of poor controllability of a traditional free radical method, inability to introduce a functional group with reactivity and the like; various tetrafluoroethane fluorine-containing materials are prepared by using different Grignard reagents.

Description

Technical Field

[0001] This invention relates to the field of organic synthesis, and in particular to a method for synthesizing tetrafluoroethane fluorine-containing materials. Background Technology

[0002] In the offset printing industry, shorter exposure wavelengths are preferred to improve the resolution of polymer images. Traditional naphthoquinone polymers are typically used at 365nm, but cannot be used in ultraviolet light at shorter wavelengths (193nm or less) because these polymers exhibit strong absorption in the short wavelength region. Chemically amplified resists are an effective solution. Chemically amplified resists are based on photochemical reactions that generate acid-catalyzing species, catalyzing a tandem reaction in the resist film; their composition includes a basic polymer and a photoacid generator.

[0003] Fluorinated tetrafluoroethane is an important intermediate in the synthesis of photoacid generating agents. Traditional synthesis methods involve the radical addition of 1,2-dibromotetrafluoroethane with olefins such as ethylene, vinyl ethyl ether, and methyl acrylate to achieve functional group transformation. For example:

[0004]

[0005] While the free radical addition method offers lower raw material costs, it requires high-risk reaction techniques such as pressurization. Furthermore, once initiated, the free radical reaction is difficult to control, easily generating various byproducts that affect yield and increase purification difficulty. Additionally, the tetrafluoroethane fluorinated materials prepared by this method do not incorporate easily functionalized groups (such as hydroxyl or carboxyl groups), often requiring further conversion to enhance their applicability. This, to some extent, limits the application of tetrafluoroethane fluorinated materials.

[0006] Therefore, there is an urgent need to provide a method for synthesizing tetrafluoroethane fluorinated materials that has low synthesis cost, high reaction controllability, and increases the functional groups in the product. Summary of the Invention

[0007] To address the aforementioned technical problems, this invention provides a method for synthesizing tetrafluoroethane fluorinated materials. Under iron-catalyzed conditions, a Grignard reagent undergoes a substitution reaction with 1,2-dibromotetrafluoroethane to generate the corresponding tetrafluoroethane fluorinated materials. This method exhibits good substrate versatility; various tetrafluoroethane fluorinated materials can be prepared using different types of Grignard reagents. Both the synthesis cost and reaction controllability are greatly improved. Furthermore, the tetrafluoroethane fluorinated materials prepared by this method possess hydroxyl or carboxyl functionalization, significantly enhancing product utilization.

[0008] This invention is achieved through the following technical solution:

[0009] The purpose of this invention is to provide a method for synthesizing tetrafluoroethane fluorine-containing materials, comprising the following steps:

[0010] In an inert gas atmosphere, the substrate and nitrogen-containing ligand were reacted in a solvent. After cooling, an iron catalyst and a Grignard reagent were added sequentially and stirred to obtain product 1.

[0011] Product 1 was subjected to a hydrolysis reaction to obtain product 2;

[0012] Add a reducing agent or an oxidizing agent to the alcohol solution of product 2, stir, and obtain the tetrafluoroethane fluorinated material;

[0013] The substrate is selected from 1,2-dibromotetrafluoroethane and / or 1,2-diiodotetrafluoroethane.

[0014] In one embodiment of the present invention, the Grignard reagent is an acetal-derived Grignard reagent.

[0015] In one embodiment of the present invention, the mass ratio of the substrate to the Grignard reagent is 1:1 to 1:2.

[0016] In one embodiment of the present invention, the nitrogen-containing ligand is selected from one or more of diisopropylethylamine, triethylamine, and tetramethylethylenediamine.

[0017] In one embodiment of the present invention, the iron catalyst is selected from one or more of trivalent iron inorganic salts, divalent iron inorganic salts, and organic iron compounds.

[0018] In one embodiment of the present invention, the trivalent iron is selected from ferric chloride and / or ferric bromide; the divalent iron is selected from ferrous chloride and / or ferrous bromide.

[0019] In one embodiment of the present invention, the organoiron compound is selected from ferric acetylacetonate and / or ferrocene.

[0020] In one embodiment of the present invention, the solvent is selected from 2-methyltetrahydrofuran and 1,4-dioxane; the volume ratio of 2-methyltetrahydrofuran to 1,4-dioxane is 1:2-2:1.

[0021] In one embodiment of the present invention, the oxidant is potassium permanganate and / or sodium periodate.

[0022] In one embodiment of the present invention, the reducing agent is one or more of sodium borohydride, calcium borohydride, and red aluminum.

[0023] Under iron catalysis and in a mixed solvent (2-methyltetrahydrofuran / 1,4-dioxane = 1 / 1, V / V), a highly active Grignard reagent is used to undergo a substitution reaction with 1,2-dibromotetrafluoroethane to generate the corresponding tetrafluoroethane fluorinated material. This catalytic system uses inexpensive and readily available ferric chloride as a catalyst and diisopropylethylamine as a ligand, without the need to add other expensive excipients.

[0024] When using Grignard reagents derived from acetals, the resulting tetrafluoroethane acetal fluorinated material can be further hydrolyzed to yield the corresponding aldehyde. Adding a reducing agent to the aldehyde yields the corresponding alcohol, while adding an oxidizing agent yields the corresponding carboxylic acid.

[0025]

[0026] Accordingly, if a Grignard reagent derived from an acetal of two equivalents is reacted with 1,2-dibromotetrafluoroethane, and then subjected to reduction or oxidation, the target compound with bilateral substitution can be obtained.

[0027]

[0028] It is obvious that 1,2-dibromotetrafluoroethane has a symmetrical structure. By adding two equivalents of Grignard reagent, two equivalents of catalyst and two equivalents of ligand, and appropriately extending the reaction time, the target compound with bilateral substitution can be obtained.

[0029] The technical solution of the present invention has the following advantages compared with the prior art:

[0030] This invention overcomes the shortcomings of traditional free radical methods, such as poor reaction controllability and the inability to introduce reactive functional groups. It utilizes inexpensive iron compounds as catalysts, enabling 1,2-dibromotetrafluoroethane to react with the substrate with high selectivity. The reaction substrate is widely applicable, allowing the preparation of various tetrafluoroethane-containing fluorinated materials using different Grignard reagents. By using acetal-derived Grignard reagents as substrates, the resulting products can be reduced or oxidized to obtain various photo-induced acid-producing intermediate compounds. Detailed Implementation

[0031] The present invention will be further described below with reference to specific embodiments, so that those skilled in the art can better understand and implement the present invention, but the embodiments are not intended to limit the present invention.

[0032] Example 1: Preparation of compound 234443-21-1.

[0033] This embodiment provides a method for synthesizing tetrafluoroethane fluorine-containing materials, the specific steps of which are as follows:

[0034]

[0035] Under argon protection, magnesium (1 mol, 1.0 equivalent) and tetrahydrofuran (2 L) were added to the reaction flask, followed by the dropwise addition of 2-bromomethyl-1,3-dioxolane (1 mol, 1.0 equivalent). After the addition was complete, the mixture was refluxed for 2 h until the magnesium was completely dissolved, thus preparing the Grignard reagent.

[0036] Under argon protection, 1,2-dibromotetrafluoroethane (1.0 mol, 1.0 equivalent), diisopropylethylamine (2.0 mol, 2.0 equivalent), and 1,4-dioxane (2 L) were added to the reactor. The reaction solution was cooled to 0°C, and FeCl3 (0.1 mol, 0.1 equivalent) was slowly added. After stirring for 30 minutes, the reaction solution was cooled to -10°C, and Grignard reagent (1.0 mol Grignard reagent dissolved in 2 L THF) was added dropwise. The mixture was stirred at -10°C for 5 hours. The reaction was monitored by GC. When the conversion rate of the starting material 1,2-dibromotetrafluoroethane reached more than 80%, the reaction was quenched by adding saturated ammonium chloride aqueous solution (2 L) while keeping the reaction system temperature below 10°C. The reaction was extracted with methyl ether (2 L × 3), washed with water (1 L × 3), washed with 7% sodium chloride solution (0.5 L × 1), and concentrated to remove the solvent to obtain a brown liquid. 2 L of tetrahydrofuran and 1 L of 2M hydrochloric acid were added to a brown liquid, and the mixture was stirred at room temperature for 16 hours. Extraction was performed with methyl ether (2 L × 3), followed by washing with water (2 L × 3) and 7% sodium chloride solution (0.5 L × 1). The mixture was concentrated to obtain a brown oily substance. 1.5 L of methanol was added to dissolve the brown oily substance. The reaction solution was cooled to -10°C, and 0.5 mol (0.5 equivalent) of sodium borohydride was added. The mixture was stirred at 0°C for 2 hours, and the reaction was quenched with water (2 L). Extraction was performed with ethyl acetate (2 L × 3), followed by washing with water (1 L × 3) and 7% sodium chloride solution (1 L × 1). The crude product obtained by concentration was a brown oily substance. The brown oily substance was purified by vacuum distillation using a packed column, collecting the fraction at 64°C-66°C and 20 mm Hg. The product was a colorless liquid with a characteristic odor, and the GC purity was >98%.

[0037] The sample was characterized by NMR, and the results are as follows: 1 H NMR (400MHz, CDCl3): δ (ppm) = 3.97 (t, 2H), 2.45-2.33 (m, 2H), 1.99 (s, 1H).

[0038] Example 2: Preparation of compound 131118-43-9.

[0039] This embodiment provides a method for synthesizing tetrafluoroethane fluorine-containing materials, the specific steps of which are as follows:

[0040]

[0041] Under argon protection, magnesium (1 mol, 1.0 equivalent) and tetrahydrofuran (2 L) were added to the reaction flask, followed by the dropwise addition of 2-bromomethyl-1,3-dioxolane (1 mol, 1.0 equivalent). After the addition was complete, the mixture was refluxed for 2 h until the magnesium was completely dissolved, thus preparing the Grignard reagent.

[0042] Under argon protection, 1,2-dibromotetrafluoroethane (1.0 mol, 1.0 equivalent), diisopropylethylamine (2.0 mol, 2.0 equivalent), and 1,4-dioxane (2 L) were added to the reactor. The reaction solution was cooled to 0°C, and FeCl3 (0.1 mol, 0.1 equivalent) was slowly added. After stirring for 30 minutes, the reaction solution was cooled to -10°C, and Grignard reagent (1.0 mol Grignard reagent dissolved in 2 L THF) was added dropwise. The mixture was stirred at -10°C for 5 hours. The reaction was monitored by GC. When the conversion rate of the starting material 1,2-dibromotetrafluoroethane reached more than 80%, the reaction was quenched by adding saturated ammonium chloride aqueous solution (2 L) while keeping the reaction system temperature below 10°C. The reaction was extracted with methyl ether (2 L × 3), washed with water (1 L × 3), washed with 7% sodium chloride solution (0.5 L × 1), and concentrated to remove the solvent to obtain a brown liquid. Add 2 L of tetrahydrofuran and 1 L of 2M hydrochloric acid to a brown liquid, stir at room temperature for 16 hours, extract with methyl ether (2 L × 3), wash the organic phase with water (2 L × 3), wash with 7% sodium chloride solution (0.5 L × 1), and concentrate to obtain a brown oily substance. Add 5 L of 5% KMnO4 solution and 1 L of 10% NaOH solution to the brown oily substance, stir at 50°C for 20 hours, wash the reaction solution with diethyl ether (500 mL × 3), separate the layers, adjust the pH of the aqueous phase to 3-4 with hydrochloric acid, extract with ethyl acetate (1 L × 4), wash the organic phase with water (1 L × 1), concentrate to remove the solvent to obtain a pale yellow oily product with GC purity > 95%.

[0043] The sample was characterized by NMR, and the results are as follows: 1 H NMR (400MHz, CDCl3): δ (ppm) = 13.15 (br, 1H), 3.11 (m, 2H).

[0044] Example 3: Preparation of compound 222725-20-4.

[0045] This embodiment provides a method for synthesizing tetrafluoroethane fluorine-containing materials, the specific steps of which are as follows:

[0046]

[0047] Under argon protection, magnesium (1 mol, 1.0 equivalent) and tetrahydrofuran (2 L) were added to the reaction flask, followed by the dropwise addition of 2-(2-bromoethyl)-1,3-dioxane (1 mol, 1.0 equivalent). After the addition was complete, the mixture was refluxed for 2 h until the magnesium was completely dissolved, thus preparing the Grignard reagent.

[0048] Under argon protection, 1,2-dibromotetrafluoroethane (1.0 mol, 1.0 equivalent), diisopropylethylamine (2.0 mol, 2.0 equivalent), and 1,4-dioxane (2 L) were added to the reactor. The reaction solution was cooled to 0°C, and FeCl3 (0.1 mol, 0.1 equivalent) was slowly added. After stirring for 30 minutes, the reaction solution was cooled to -10°C, and Grignard reagent (1.0 mol Grignard reagent dissolved in 2 L THF) was added dropwise. The mixture was stirred at -10°C for 5 hours. The reaction was monitored by GC. When the conversion rate of the starting material 1,2-dibromotetrafluoroethane reached more than 80%, the reaction was quenched by adding saturated ammonium chloride aqueous solution (2 L) while keeping the reaction system temperature below 10°C. The reaction was extracted with methyl ether (2 L × 3), washed with water (1 L × 3), washed with 7% sodium chloride solution (0.5 L × 1), and concentrated to remove the solvent to obtain a brown liquid. 2 L of tetrahydrofuran and 1 L of 2M hydrochloric acid were added to a brown liquid, and the mixture was stirred at room temperature for 16 hours. Extraction was performed with methyl ether (2 L × 3), followed by washing with water (2 L × 3) and 7% sodium chloride solution (0.5 L × 1). The mixture was concentrated to obtain a brown oily substance. 1.5 L of methanol was added to dissolve the brown oily substance. The reaction solution was cooled to -10°C, and 0.5 mol (0.5 equivalent) of sodium borohydride was added. The mixture was stirred at 0°C for 2 hours, and the reaction was quenched with water (2 L). Extraction was performed with ethyl acetate (2 L × 3), followed by washing with water (1 L × 3) and 7% sodium chloride solution (1 L × 1). The crude product obtained by concentration was a brown oily substance. The brown oily substance was purified by vacuum distillation using a packed column, collecting the fraction at 77°C-80°C and 20 mm Hg. The product was a colorless liquid with a characteristic odor and a GC purity > 98%.

[0049] The sample was characterized by NMR, and the results are as follows: 1 H NMR (400MHz, CDCl3): δ (ppm) = 3.18 (t, 2H), 2.70-2.61 (m, 2H), 2.44-2.09 (m, 2H).

[0050] Example 4: Preparation of compound 234443-22-2.

[0051] This embodiment provides a method for synthesizing tetrafluoroethane fluorine-containing materials, the specific steps of which are as follows:

[0052]

[0053] Under argon protection, magnesium (1 mol, 1.0 equivalent) and tetrahydrofuran (2 L) were added to the reaction flask, followed by the dropwise addition of 2-(2-bromoethyl)-1,3-dioxane (1 mol, 1.0 equivalent). After the addition was complete, the mixture was refluxed for 2 h until the magnesium was completely dissolved, thus preparing the Grignard reagent.

[0054] Under argon protection, 1,2-dibromotetrafluoroethane (1.0 mol, 1.0 equivalent), diisopropylethylamine (2.0 mol, 2.0 equivalent), and 1,4-dioxane (2 L) were added to the reactor. The reaction solution was cooled to 0°C, and FeCl3 (0.1 mol, 0.1 equivalent) was slowly added. After stirring for 30 minutes, the reaction solution was cooled to -10°C, and Grignard reagent (1.0 mol Grignard reagent dissolved in 2 L THF) was added dropwise. The mixture was stirred at -10°C for 5 hours. The reaction was monitored by GC. When the conversion rate of the starting material 1,2-dibromotetrafluoroethane reached more than 80%, the reaction was quenched by adding saturated ammonium chloride aqueous solution (2 L) while keeping the reaction system temperature below 10°C. The reaction was extracted with methyl ether (2 L × 3), washed with water (1 L × 3), washed with 7% sodium chloride solution (0.5 L × 1), and concentrated to remove the solvent to obtain a brown liquid. Add 2 L of tetrahydrofuran and 1 L of 2M hydrochloric acid to a brown liquid, stir at room temperature for 16 hours, extract with methyl ether (2 L × 3), wash the organic phase with water (2 L × 3), wash with 7% sodium chloride solution (0.5 L × 1), and concentrate to obtain a brown oily substance. Add 5 L of 5% KMnO4 solution and 1 L of 10% NaOH solution to the brown oily substance, stir at 50°C for 20 hours, wash the reaction solution with diethyl ether (500 mL × 3), separate the layers, adjust the pH of the aqueous phase to 3-4 with hydrochloric acid, extract with ethyl acetate (1 L × 4), wash the organic phase with water (1 L × 1), concentrate to remove the solvent to obtain a pale yellow oily product with GC purity > 95%.

[0055] The sample was characterized by NMR, and the results are as follows: 1 H NMR (400MHz, CDCl3): δ (ppm) = 12.98 (br, 1H), 2.44-2.34 (m, 2H), 2.21-2.03 (m, 2H).

[0056] Example 5: Preparation of bilaterally substituted products.

[0057] This embodiment provides a method for synthesizing tetrafluoroethane fluorine-containing materials, the specific steps of which are as follows:

[0058]

[0059] Under argon protection, magnesium (2 mol, 2.0 equivalent) and tetrahydrofuran (4 L) were added to the reaction flask, followed by the dropwise addition of 2-bromomethyl-1,3-dioxolane (2 mol, 1.0 equivalent). After the addition was complete, the mixture was refluxed for 2 h until the magnesium was completely dissolved, thus preparing the Grignard reagent.

[0060] Under argon protection, 1,2-dibromotetrafluoroethane (1.0 mol, 1.0 equivalent), diisopropylethylamine (4.0 mol, 4.0 equivalent), and 1,4-dioxane (2 L) were added to the reactor. The reaction solution was cooled to 0°C, and FeCl3 (0.2 mol, 0.2 equivalent) was slowly added. After stirring for 30 minutes, the reaction solution was cooled to -10°C, and Grignard reagent (2.0 mol Grignard reagent dissolved in 4 L THF) was added dropwise. The mixture was stirred at -10°C for 5 hours. The reaction was monitored by GC. When the conversion rate of the starting material 1,2-dibromotetrafluoroethane reached more than 80%, the reaction was quenched by adding saturated ammonium chloride aqueous solution (2 L) while keeping the reaction system temperature below 10°C. The reaction was extracted with methyl ether (2 L × 3), washed with water (1 L × 3), washed with 7% sodium chloride solution (0.5 L × 1), and concentrated to remove the solvent to obtain a brown liquid. 2 L of tetrahydrofuran and 1 L of 2M hydrochloric acid were added to a brown liquid, and the mixture was stirred at room temperature for 16 hours. Extraction was performed with methyl ether (2 L × 3), followed by washing with water (2 L × 3) and 7% sodium chloride solution (0.5 L × 1). The mixture was concentrated to obtain a brown oily substance. 1.5 L of methanol was added to dissolve the brown oily substance. The reaction solution was cooled to -10°C, and sodium borohydride (1 mol, 1 equivalent) was added. The mixture was stirred at 0°C for 2 hours, and the reaction was quenched with water (2 L). Extraction was performed with ethyl acetate (2 L × 3), followed by washing with water (1 L × 3) and 7% sodium chloride solution (1 L × 1). The crude product obtained by concentration was a brown oily substance. The brown oily substance was purified by vacuum distillation using a packed column, collecting the fraction at 155-160°C and 20 mm Hg. The product was a colorless liquid with a characteristic odor and a GC purity > 97%.

[0061] The sample was characterized by NMR, and the results are as follows: 1 H NMR (400MHz, CDCl3): δ (ppm) = 3.97 (t, 4H), 2.45-2.33 (m, 4H), 1.99 (s, 2H).

[0062] Comparative Example

[0063] This comparative example provides a method for synthesizing tetrafluoroethane fluorine-containing materials, the specific steps of which are as follows:

[0064]

[0065] Under argon protection, magnesium (1 mol, 1.0 equivalent) and tetrahydrofuran (2 L) were added to the reaction flask, followed by the dropwise addition of 2-bromomethyl-1,3-dioxolane (1 mol, 1.0 equivalent). After the addition was complete, the mixture was refluxed for 2 h until the magnesium was completely dissolved, thus preparing the Grignard reagent.

[0066] Under argon protection, 1,2-dibromotetrafluoroethane (1.0 mol, 1.0 equivalent), diisopropylethylamine (2.0 mol, 2.0 equivalent), and 1,4-dioxane (2 L) were added to the reactor. The reaction solution was cooled to 0°C and stirred for 30 minutes. Then, the reaction solution was cooled to -10°C, and Grignard reagent (1.0 mol Grignard reagent dissolved in 2 L THF) was added dropwise. The mixture was stirred at -10°C for 5 hours. GC monitoring showed that the conversion rate of the starting material 1,2-dibromotetrafluoroethane was less than 1%.

[0067] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A method for the synthesis of tetrafluoroethane fluorinated material, characterized by: Includes the following steps: In an inert gas atmosphere, the substrate and nitrogen-containing ligand were reacted in a solvent. After cooling, an iron catalyst and a Grignard reagent were added sequentially and stirred to obtain product 1. Product 1 was subjected to a hydrolysis reaction to obtain product 2; Add a reducing agent or an oxidizing agent to the alcohol solution of product 2, stir, and obtain the tetrafluoroethane fluorinated material; The substrate is selected from 1,2-dibromotetrafluoroethane and / or 1,2-diiodotetrafluoroethane; The Grignard reagent is an acetal-derived Grignard reagent.

2. The method of synthesis of claim 1, wherein: The mass ratio of the substrate to the Grignard reagent is 1:1 to 1:

2.

3. The synthesis method according to claim 1, characterized in that: The nitrogen-containing ligand is selected from one or more of diisopropylethylamine, triethylamine, and tetramethylethylenediamine.

4. The synthesis method according to claim 1, characterized in that: The iron catalyst is selected from one or more of trivalent iron inorganic salts, divalent iron inorganic salts, and organic iron compounds.

5. The synthesis method according to claim 4, characterized in that: The ferric iron is selected from ferric chloride and / or ferric bromide; the ferrous iron is selected from ferrous chloride and / or ferrous bromide.

6. The synthesis method according to claim 4, characterized in that: The organoiron compound is selected from ferric acetylacetonate and / or ferrocene.

7. The synthesis method according to claim 1, characterized in that: The solvent is selected from 2-methyltetrahydrofuran and 1,4-dioxane; the volume ratio of 2-methyltetrahydrofuran to 1,4-dioxane is 1:2-2:

1.

8. The synthesis method according to claim 1, characterized in that: The oxidant is potassium permanganate and / or sodium periodate.

9. The synthesis method according to claim 1, characterized in that: The reducing agent is one or more of sodium borohydride, calcium borohydride, and red aluminum.

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