Preparation method of 5-norbornene-2, 3-dimethyl imino trifluoromethanesulfonate

Abstract

The invention discloses a preparation method of 5-norbornene-2, 3-dimethyl imino trifluoromethanesulfonate, which comprises the following steps: by taking trifluoromethanesulfonic anhydride and N-hydroxyl-5-norbornene-2, 3-dicarboximide as starting materials, carrying out substitution reaction under the action of a catalyst to generate the 5-norbornene-2, 3-dimethyl imino trifluoromethanesulfonate, and carrying out reaction on the 5-norbornene-2, 3-dimethyl imino trifluoromethanesulfonate and the N-hydroxyl-5-norbornene-2, 3-dimethyl imino trifluoromethanesulfonate to obtain the 5-norbornene-2, 3-dimethyl imino trifluoromethanesulfonate. The preparation method comprises the following steps: washing with water, spin-drying and pulping to obtain a crude product, and washing and concentrating the crude product to obtain a 5-norbornene-2, 3-dimethyl imino trifluoromethanesulfonate product; the catalyst is 4-dimethylaminopyridine or polystyrene loaded with the 4-dimethylaminopyridine; the catalytic performance selected by the method is better than that of traditional pyridine, and particularly polystyrene loaded with 4-dimethylaminopyridine is high in catalytic efficiency and convenient to recycle and activate for secondary utilization.

Description

Technical Field

[0001] The invention belongs to the technical field of organic synthesis, and in particular relates to a method for preparing 5-norbornene-2,3-dimethylimino trifluoromethanesulfonate. Background Art

[0002] 5-Norbornene-2,3-dimethylimino trifluoromethanesulfonate is a nonionic photoacid generator commonly used in photoresists. Photoacid generators decompose under exposure to radiation, such as light, radiation, or plasma, to generate specific acids. These acids decompose or crosslink acid-sensitive resins, dissolving the illuminated and non-illuminated portions, creating a difference in affinity. After development, these substances form an image. Photoacid generators are widely used and researched in imaging systems, including various chemically amplified resists. They are also widely used in cationic photocurable materials and thermal printing plates.

[0003] Regarding the preparation method of 5-norbornene-2,3-dimethylimino trifluoromethanesulfonate, one synthetic route is to use N-hydroxy-5-bornene-2,3-dicarboximide and trifluoromethanesulfonic anhydride to react, using triethylamine or pyridine as an acid-binding agent. The reaction process takes 7 to 9 hours under low temperature conditions. The reaction yield in the existing technology is only 50% to 60%, and the product purity is low.

[0004] Therefore, it is necessary to study the preparation method of 5-norbornene-2,3-dimethylimino trifluoromethanesulfonate to improve the purity and yield of the product. Summary of the Invention

[0005] The purpose of the present invention is to improve the purity and yield of the product, and to study the preparation method of 5-norbornene-2,3-dimethylimino trifluoromethanesulfonate.

[0006] The technical solution adopted by the present invention is a method for preparing 5-norbornene-2,3-dimethylimino trifluoromethanesulfonate. The key point is that the preparation method uses trifluoromethanesulfonic anhydride and N-hydroxy-5-norbornene-2,3-dicarboximide as starting materials, undergoes a substitution reaction under the action of a catalyst to generate 5-norbornene-2,3-dimethylimino trifluoromethanesulfonate, washes with water, spin-dried, and pulped to obtain a crude product, and washes and concentrates the crude product to obtain the 5-norbornene-2,3-dimethylimino trifluoromethanesulfonate product; the catalyst is 4-dimethylaminopyridine or polystyrene loaded with 4-dimethylaminopyridine; and the synthesis route is:

[0007]

[0008] Specifically, the molar ratio of the above-mentioned N-hydroxy-5-norbornene-2,3-dicarboximide, trifluoromethanesulfonic anhydride and 4-dimethylaminopyridine is 1:1.0-1.2:0.3-0.5.

[0009] Specifically, the molar ratio of the N-hydroxy-5-norbornene-2,3-dicarboximide, trifluoromethanesulfonic anhydride, and 4-dimethylaminopyridine-loaded polystyrene is 1:1.0-1.2:30-50.

[0010] Furthermore, the above-mentioned 4-dimethylaminopyridine-loaded polystyrene is prepared by amination of chloromethylated polystyrene resin under the action of an aminating agent, and then reacting with 4-chloropyridine.

[0011] Furthermore, after the chloromethylated polystyrene resin is swollen with a toluene solvent, an amination reagent is added, the temperature is raised to 80°C to 90°C and the reaction is carried out for 18h to 24h, and then 4-chloropyridine is added and the reaction is carried out at 55°C to 65°C for 10h to 14h. After washing and drying, the chloromethylated polystyrene resin is obtained; the molar ratio of the chloromethylated polystyrene resin, the amination reagent and the 4-chloropyridine is 500:1~1.5:1.0~1.5; the amination reagent is any one of methanolamine, triethylenetetramine or cyclamates.

[0012] Preferably, the reaction time of the above-mentioned substitution reaction is 1 hour to 8 hours; during the above-mentioned substitution reaction, the reaction system needs to be cooled to below 0°C; the above-mentioned substitution reaction needs to be carried out in an organic solvent under the protection of an inert gas; the above-mentioned organic solvent is any one or a combination of tetrahydrofuran or dichloromethane.

[0013] Preferably, the solvent used in the beating is n-hexane; and the detergent used in the crude product washing is ammonia water containing a metal chelating agent.

[0014] Optimally, the mass concentration of the metal chelating agent is 5% to 15%, and the metal chelating agent is any one or a combination of EDTA and EGTA; the mass concentration of the ammonia water is 10% to 20%.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] The present invention uses trifluoromethanesulfonic anhydride and N-hydroxy-5-norbornene-2,3-dicarboximide as starting materials, and a substitution reaction occurs under the action of a catalyst, 4-dimethylaminopyridine or supported 4-dimethylaminopyridine, to produce 5-norbornene-2,3-dimethylimino trifluoromethanesulfonate. The catalytic performance of the present invention is better than that of traditional triethylamine or pyridine. In particular, the 4-dimethylaminopyridine-supported polystyrene is prepared by thoroughly aminated a chloromethylated polystyrene resin with an aminating agent and then reacting it with 4-chloropyridine. This not only has high catalytic efficiency but also facilitates recovery and activation for secondary use.

[0017] The yield and purity of the product prepared by the present invention are both improved, with the purity reaching over 99.9% and approaching 100%. The content of metal impurities in the product of the present invention is controlled within 60 ppb. The present invention uses a mixed ammonia solution containing metal chelating agents EDTA and EGTA to wash the crude product, which can further reduce the content of metal impurities and improve the purity of the product, fully meeting the requirements for use as an electronic chemical. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is the H NMR spectrum of sample 4 of the present invention.

[0019] Figure 2 This is the gas chromatography-mass spectrometer of sample 4 of the present invention.

[0020] Figure 3 This is the high-efficiency gas phase spectrum of sample 4 of the present invention. DETAILED DESCRIPTION

[0021] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of them. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0022] If the specific conditions are not specified in the examples, the experiments can be carried out under conventional conditions; if the manufacturers of the reagents or instruments are not specified, they are all conventional products that can be purchased from the market.

[0023] Example 1

[0024] In this embodiment, trifluoromethanesulfonic anhydride and N-hydroxy-5-norbornene-2,3-dicarboximide are used as starting materials, and a substitution reaction is carried out under the action of a catalyst 4-dimethylaminopyridine to produce 5-norbornene-2,3-dimethylimino trifluoromethanesulfonate. The specific process is:

[0025] S1. Under inert gas protection, add 500 mL of a mixed solvent of dichloromethane and tetrahydrofuran (volume ratio of 1:1) to a reaction flask, add 1 mol of N-hydroxy-5-norbornene-2,3-dicarboximide and 0.4 mol of 4-dimethylaminopyridine, cool the reaction system to -5°C, add 1.1 mol of trifluoromethanesulfonic anhydride dropwise, and react for 2.5 hours after the addition is complete;

[0026] S2. After the reaction is completed, the crude product is washed with water, the solvent is dried by spin drying, and then slurried with n-hexane and filtered to obtain a crude product;

[0027] S3. Dissolve the crude product in dichloromethane and wash 15 times with aqueous ammonia containing EDTA and EGTA, where the mass concentration of the aqueous ammonia is 18% and the mass concentrations of EDTA and EGTA are both 5%. Concentrate the product to obtain a product, which is recorded as product sample 1.

[0028] Example 2

[0029] In this embodiment, trifluoromethanesulfonic anhydride and N-hydroxy-5-norbornene-2,3-dicarboximide are used as starting materials, and a substitution reaction is carried out under the action of a catalyst 4-dimethylaminopyridine to produce 5-norbornene-2,3-dimethylimino trifluoromethanesulfonate. The specific process is:

[0030] S1. Under inert gas protection, add 500 mL of a mixed solvent of tetrahydrofuran, 1 mol of N-hydroxy-5-norbornene-2,3-dicarboximide and 0.3 mol of 4-dimethylaminopyridine to a reaction flask, cool the reaction system to -8°C, and dropwise add 1.2 mol of trifluoromethanesulfonic anhydride. After the addition is complete, react for 1.0 h.

[0031] S2. After the reaction is completed, the crude product is washed with water, the solvent is dried by spin drying, and then slurried with n-hexane and filtered to obtain a crude product;

[0032] S3. Dissolve the crude product in dichloromethane and wash 20 times with aqueous ammonia containing EDTA, where the mass concentration of the aqueous ammonia is 10% and the mass concentration of EDTA is 15%. Concentrate the product to obtain the product, which is recorded as product sample 2.

[0033] Example 3

[0034] In this embodiment, trifluoromethanesulfonic anhydride and N-hydroxy-5-norbornene-2,3-dicarboximide are used as starting materials, and a substitution reaction is carried out under the action of a catalyst 4-dimethylaminopyridine to produce 5-norbornene-2,3-dimethylimino trifluoromethanesulfonate. The specific process is:

[0035] S1. Under inert gas protection, add 500 mL of a mixed solvent of tetrahydrofuran, 1 mol of N-hydroxy-5-norbornene-2,3-dicarboximide and 0.3 mol of 4-dimethylaminopyridine to a reaction flask, cool the reaction system to -8°C, and dropwise add 1.0 mol of trifluoromethanesulfonic anhydride. After the addition is complete, react for 3.0 hours.

[0036] S2. After the reaction is completed, the crude product is washed with water, the solvent is dried by spin drying, and then slurried with n-hexane and filtered to obtain a crude product;

[0037] S3. Dissolve the crude product in dichloromethane and wash 25 times with aqueous ammonia containing EDTA, where the concentration of the aqueous ammonia is 20% and the concentration of the EDTA is 5%. Concentrate the product to obtain the product, which is designated as product sample 3.

[0038] Example 4

[0039] In this embodiment, trifluoromethanesulfonic anhydride and N-hydroxy-5-norbornene-2,3-dicarboximide are used as starting materials, and a substitution reaction is carried out under the action of polystyrene supported by 4-dimethylaminopyridine as a catalyst to produce 5-norbornene-2,3-dimethylimino trifluoromethanesulfonate. The specific process is:

[0040] S1. Fill the reaction column with 40 mol of 4-dimethylaminopyridine-loaded polystyrene sample 1. Under inert gas protection, evenly mix 1 mol of N-hydroxy-5-norbornene-2,3-dicarboximide and 500 mL of a mixed solvent of dichloromethane and tetrahydrofuran (volume ratio of 1:1). Cool the reaction system to -5°C, introduce the mixed solvent containing N-hydroxy-5-norbornene-2,3-dicarboximide, and simultaneously add 1.1 mol of trifluoromethanesulfonic anhydride dropwise for reflux reaction for 2.5 h.

[0041] S2. After the reaction is completed, the catalyst is filtered off, the reaction solution is washed with water, the solvent is dried by spin drying, and then slurried with n-hexane and filtered to obtain a crude product;

[0042] S3. Dissolve the crude product in dichloromethane and wash 15 times with aqueous ammonia containing EDTA and EGTA, where the mass concentration of the aqueous ammonia is 18% and the mass concentrations of EDTA and EGTA are both 5%. Concentrate the product to obtain a product, which is recorded as product sample 4.

[0043] The preparation method of the polystyrene loaded with 4-dimethylaminopyridine used in this embodiment is:

[0044] After 40 mol of chloromethylated polystyrene resin was fully swollen with toluene solvent, 0.10 mol of amination reagent cyclopentane was added, the temperature was raised to 85°C and the reaction was carried out for 20 hours, and then 0.10 mol of 4-chloropyridine was added and the reaction was carried out at 60°C for 12 hours. After washing and drying, chloromethylated polystyrene resin sample 1 was obtained.

[0045] In this embodiment, the molar ratio of the chloromethylated polystyrene resin sample 1, the amination reagent, and 4-chloropyridine is 500:1.2:1.2.

[0046] Example 5

[0047] In this embodiment, trifluoromethanesulfonic anhydride and N-hydroxy-5-norbornene-2,3-dicarboximide are used as starting materials, and a substitution reaction is carried out under the action of polystyrene supported by 4-dimethylaminopyridine as a catalyst to produce 5-norbornene-2,3-dimethylimino trifluoromethanesulfonate. The specific process is:

[0048] S1. Fill the reaction column with 50 mol of 4-dimethylaminopyridine-loaded polystyrene sample 2. Under inert gas protection, evenly mix 1 mol of N-hydroxy-5-norbornene-2,3-dicarboximide and 500 mL of a mixed solvent of dichloromethane and tetrahydrofuran (volume ratio of 1:1). Cool the reaction system to -5°C, introduce the mixed solvent containing N-hydroxy-5-norbornene-2,3-dicarboximide, and simultaneously add 1.1 mol of trifluoromethanesulfonic anhydride dropwise for reflux reaction for 2.5 h.

[0049] S2. After the reaction is completed, the catalyst is filtered off, the reaction solution is washed with water, the solvent is dried by spin drying, and then slurried with n-hexane and filtered to obtain a crude product;

[0050] S3. Dissolve the crude product in dichloromethane and wash 15 times with aqueous ammonia containing EDTA and EGTA, where the mass concentration of the aqueous ammonia is 18% and the mass concentrations of EDTA and EGTA are both 5%. Concentrate the product to obtain a product, which is recorded as product sample 5.

[0051] The preparation method of the polystyrene loaded with 4-dimethylaminopyridine used in this embodiment is:

[0052] After 50 mol of chloromethylated polystyrene resin was fully swollen with toluene solvent, 0.10 mol of amination reagent triethylenetetramine was added, the temperature was raised to 90°C and the reaction was carried out for 24 hours, and then 0.15 mol of 4-chloropyridine was added and the reaction was carried out at 55°C for 14 hours. After washing and drying, chloromethylated polystyrene resin sample 2 was obtained.

[0053] In this embodiment, the molar ratio of the chloromethylated polystyrene resin sample 2, the amination reagent, and 4-chloropyridine is 500:1.0:1.5.

[0054] Example 6

[0055] In this embodiment, trifluoromethanesulfonic anhydride and N-hydroxy-5-norbornene-2,3-dicarboximide are used as starting materials, and a substitution reaction is carried out under the action of polystyrene supported by 4-dimethylaminopyridine as a catalyst to produce 5-norbornene-2,3-dimethylimino trifluoromethanesulfonate. The specific process is:

[0056] S1. Fill the reaction column with 30 mol of 4-dimethylaminopyridine-loaded polystyrene sample 3. Under inert gas protection, evenly mix 1 mol of N-hydroxy-5-norbornene-2,3-dicarboximide and 500 mL of a mixed solvent of dichloromethane and tetrahydrofuran (volume ratio of 1:1). Cool the reaction system to -5°C, introduce the mixed solvent containing N-hydroxy-5-norbornene-2,3-dicarboximide, and simultaneously add 1.1 mol of trifluoromethanesulfonic anhydride dropwise for reflux reaction for 2.5 h.

[0057] S2. After the reaction is completed, the catalyst is filtered off, the reaction solution is washed with water, the solvent is dried by spin drying, and then slurried with n-hexane and filtered to obtain a crude product;

[0058] S3. Dissolve the crude product in dichloromethane and wash 15 times with aqueous ammonia containing EDTA and EGTA, where the mass concentration of the aqueous ammonia is 18% and the mass concentrations of EDTA and EGTA are both 5%. Concentrate the product to obtain a product, which is recorded as product sample 6.

[0059] The preparation method of the polystyrene loaded with 4-dimethylaminopyridine used in this embodiment is:

[0060] After 30 mol of chloromethylated polystyrene resin was fully swollen with toluene solvent, 0.09 mol of amination reagent methanolamine was added, the temperature was raised to 80°C and the reaction was carried out for 18 hours, and then 0.06 mol of 4-chloropyridine was added and the reaction was carried out at 65°C for 10 hours. After washing and drying, chloromethylated polystyrene resin sample 3 was obtained.

[0061] In this embodiment, the molar ratio of the chloromethylated polystyrene resin sample 3, the amination reagent, and 4-chloropyridine is 500:1.5:1.0.

[0062] Comparative Example 1

[0063] The specific preparation process is the same as that of Example 1, except that in step S1, 1 mol of pyridine is used instead of 4-dimethylaminopyridine as a catalyst. The subsequent preparation process is the same as that of Example 1 to prepare reference product 1.

[0064] Comparative Example 2

[0065] The specific preparation process is the same as that of Example 1, except that in step S3, ammonia water containing EDTA and EGTA is not used for washing, but ammonia water of equal mass concentration is used for washing the same number of times. The subsequent preparation process is the same as that of Example 1 to prepare reference substance 2.

[0066] Analysis and testing

[0067] The samples prepared by the present invention were analyzed by nuclear magnetic hydrogen spectrum and high performance gas chromatography-mass spectrometry, and confirmed to be consistent with the structural characteristics of 5-norbornene-2,3-dimethylimino trifluoromethanesulfonate. The test spectrum of product sample 4 can be found in Figure 1 and Figure 2 .

[0068] The purity of the product samples and the reference substance was determined by high-performance gas chromatography, and the yield was calculated by the following formula. The results are shown in Table 1;

[0069] Elemental analysis is also required for product samples. The test results of metal impurities are shown in Table 2. The high-efficiency gas phase test spectrum of product sample 4 is shown in Figure 3 .

[0070] The yield calculation formula is:

[0071] Product yield = actual weight of the obtained product (g) / theoretical amount calculated based on the amount of N-hydroxy-5-norbornene-2,3-dicarboximide used (g) × 100%.

[0072] Table 1: Summary of purity and yield results

[0073]

[0074]

[0075] As can be seen from the results in Table 1, the purity of the samples prepared by the present invention reaches above 99.9%, close to 100%, and the impurities in some samples are not detected under the gas phase conditions of the present invention; the content of metal impurities in the product of the present invention is controlled within 60 ppb.

[0076] The present invention uses 4-dimethylaminopyridine or 4-dimethylaminopyridine-loaded polystyrene as a catalyst, which exhibits superior catalytic performance compared to conventional pyridine. In particular, the 4-dimethylaminopyridine-loaded polystyrene is prepared by thoroughly aminating a chloromethylated polystyrene resin with an aminating agent and then reacting it with 4-chloropyridine. This method not only exhibits high catalytic efficiency but also facilitates recovery and activation for secondary use.

[0077] The research found that the present invention uses mixed ammonia water with metal chelating agents EDTA and EGTA to wash the crude product, which can better reduce the metal impurity content, improve the purity of the product, and fully meet the requirements for use as electronic chemicals.

Claims

The preparation method of 1,5-norbornene-2,3-dimethylimino trifluoromethanesulfonate is characterized in that: The preparation method uses trifluoromethanesulfonic anhydride and N-hydroxy-5-norbornene-2,3-dicarboximide as starting materials, undergoes a substitution reaction under the action of a catalyst to generate 5-norbornene-2,3-dimethylimino trifluoromethanesulfonate, and then washes the mixture with water, spin-dried, and pulped to obtain a crude product. The crude product is then washed and concentrated to obtain the 5-norbornene-2,3-dimethylimino trifluoromethanesulfonate product. The catalyst is 4-dimethylaminopyridine or polystyrene loaded with 4-dimethylaminopyridine. The synthetic route is:

2. The method for preparing 5-norbornene-2,3-dimethylimino trifluoromethanesulfonate according to claim 1, wherein: The molar ratio of the N-hydroxy-5-norbornene-2,3-dicarboximide, trifluoromethanesulfonic anhydride and 4-dimethylaminopyridine is 1:1.0-1.2:0.3-0.

5.

3. The method for preparing 5-norbornene-2,3-dimethylimino trifluoromethanesulfonate according to claim 1, wherein: The molar ratio of the N-hydroxy-5-norbornene-2,3-dicarboximide, trifluoromethanesulfonic anhydride and the polystyrene loaded with 4-dimethylaminopyridine is 1:1.0-1.2:30-50.

4. The method for preparing 5-norbornene-2,3-dimethylimino trifluoromethanesulfonate according to claim 1, wherein: The 4-dimethylaminopyridine-loaded polystyrene is prepared by subjecting a chloromethylated polystyrene resin to amination under the action of an aminating agent and then reacting with 4-chloropyridine.

5. The method for preparing 5-norbornene-2,3-dimethylimino trifluoromethanesulfonate according to claim 4, wherein: After swell-forming a chloromethylated polystyrene resin with toluene solvent, an aminating agent is added, the temperature is raised to 80°C to 90°C and the reaction is carried out for 18 to 24 hours, and then 4-chloropyridine is added and the reaction is carried out at 55°C to 65°C for 10 to 14 hours. After washing and drying, the chloromethylated polystyrene resin is obtained. The molar ratio of the chloromethylated polystyrene resin, the aminating agent, and the 4-chloropyridine is 500:1 to 1.5:1.0 to 1.

5. The aminating agent is any one of methanolamine, triethylenetetramine, or cyclamates.

6. The method for preparing 5-norbornene-2,3-dimethylimino trifluoromethanesulfonate according to claim 1, characterized in that: The reaction time of the substitution reaction is 1 h to 8 h; during the substitution reaction, the reaction system needs to be cooled to below 0° C.; the substitution reaction needs to be carried out in an organic solvent under the protection of an inert gas; the organic solvent is any one or a combination of tetrahydrofuran or dichloromethane.

7. The method for preparing 5-norbornene-2,3-dimethylimino trifluoromethanesulfonate according to claim 1, characterized in that: The solvent used in the pulping is n-hexane; the detergent used in the crude product washing is ammonia water containing a metal chelating agent.

8. The method for preparing 5-norbornene-2,3-dimethylimino trifluoromethanesulfonate according to claim 7, characterized in that: The mass concentration of the metal chelating agent is 5% to 15%, and the metal chelating agent is any one of EDTA and EGTA or a combination thereof; the mass concentration of the ammonia water is 10% to 20%.

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