Synthesis method of 3-ethyl-3-[(2-oxirane methoxy) methyl] oxetane

Abstract

The invention provides a synthesis method of 3-ethyl-3-[(2-oxirane methoxy) methyl] oxetane (EGMO), and belongs to the technical field of fine chemical engineering. According to the method, sodium hydroxide is taken as an alkaline reagent, and a quaternary ammonium salt or quaternary phosphonium salt phase transfer catalyst is adopted to promote the effective contact of sodium salt and epichlorohydrin, so that the conversion process of preparing 3-ethyl-3-[(2-oxirane methoxy) methyl] oxetane from 3-ethyl-3-oxetane and epichlorohydrin is catalyzed. According to the method disclosed by the invention, the EGMO is synthesized by dropwise adding the epoxy chloropropane through a one-pot method, and a product with relatively high content and relatively low color number can be obtained without distillation, so that the reaction time is shortened, the side reaction of the epoxy chloropropane is reduced, the production efficiency, the product yield and the purity are improved, and the color number of the product is reduced. The preparation process is convenient to operate, simple and suitable for industrial production.

Description

Technical Field

[0001] The invention relates to a method for synthesizing 3-ethyl-3-[(2-oxiranylmethoxy)methyl]oxetane, belonging to the technical field of fine chemicals. Background Art

[0002] 3-ethyl-3-[(2-oxiranylmethoxy)methyl]oxetane, referred to as EGMA, CAS15957-34-3, contains two epoxy groups, oxetane and oxirane, in its molecular structure, and the ring tension of the epoxy group causes it to react easily with various nucleophilic groups. Moreover, the resin composition containing the oxetane compound as a component shrinks little during curing, and its cured product (resin) has excellent toughness, mechanical properties, heat resistance, electrical properties, water resistance, weather resistance, transparency, etc. Due to this excellent feature, the resin composition containing the oxetane compound is being used as a raw material for coating materials, coatings, inks, adhesive materials, bonding materials, films, pastes, optical materials, sealing materials, resist materials, etc.

[0003] Common synthesis methods of EGMA include phase transfer catalytic one-step synthesis, etherification-ring closure, enzyme catalytic synthesis, etc. Among them, the one-step synthesis of epichlorohydrin and 3-ethyl-3-oxetane methanol is the currently commonly used EGMA synthesis process due to its relatively mild reaction conditions, short reaction time, easy operation, low pollution, and common and easily available catalysts.

[0004] In the traditional one-step synthesis method, excess epichlorohydrin is used as a reaction raw material and also as a reaction solvent, reacting with 3-ethyl-3-oxabutane methanol under the catalysis of a phase transfer catalyst to generate EGMA. When epichlorohydrin is used as a solvent, the amount added is much higher than the theoretical amount. Epichlorohydrin is easy to react with chloride ions generated during the reaction to generate chlorine-containing impurities, which affects the secondary utilization of epichlorohydrin and also affects the effective separation of EGMA. In addition, the traditional method uses a batch alkali addition method to control the reaction temperature, which is cumbersome and easy to cause high temperature, resulting in a high color number. The product needs to be steamed out. Taking the production of a 2 cubic meter reactor as an example, the reaction stage takes more than 12 hours, and the post-treatment includes filtration, water washing extraction, and distillation takes 40-50 hours. Therefore, the traditional one-step synthesis method has the disadvantages of waste of raw materials, low product purity, cumbersome operation, high time cost, more by-products, and high color number.

[0005] At present, many processes have improved the phase transfer catalytic one-step synthesis method, and these improvements focus more on the reaction temperature and the type of phase transfer catalyst. However, the improvement of the process route will further improve the reaction efficiency, reduce the occurrence of background reactions, and improve the purity of the product. Summary of the invention

[0006] The technical problem to be solved by the present invention is to address the shortcomings of a conventional one-step synthesis method involving phase transfer catalysis, such as waste of raw materials, low purity of products, complicated operation, high time cost, more by-products and high color number. Sodium hydroxide is used as a base, a phase transfer catalyst is used, and the temperature is controlled while adding dropwise to react, so that the occurrence of side reactions is reduced, and efficient conversion of epichlorohydrin and 3-ethyl-3-oxetane methanol is achieved to obtain a high-purity EGMA product.

[0007] The invention discloses a method for preparing 3-ethyl-3-[(2-oxiranylmethoxy)methyl]oxetane, comprising the following steps: using 3-ethyl-3-oxetane methanol epichlorohydrin as raw materials, reacting in the presence of a solid base and a phase transfer catalyst to obtain 3-ethyl-3-[(2-oxiranylmethoxy)methyl]oxetane.

[0008] Furthermore, in the above technical scheme, the reaction principle is: using a solid alkaline reagent, under the joint action of a phase transfer catalyst, promote the effective contact between the generated sodium salt and epichlorohydrin, catalyze the reaction between 3-ethyl-3-oxetanemethanol and epichlorohydrin, and generate 3-ethyl-3-[(2-oxiranylmethoxy)methyl]oxetane (EGMA).

[0009] Furthermore, in the above technical solution, the solid base is selected from sodium methoxide, sodium ethoxide, sodium hydroxide or potassium hydroxide.

[0010] Furthermore, in the above technical solution, the phase transfer catalyst is selected from tetrabutylammonium bromide, triethylbenzylammonium chloride, tetramethylammonium chloride, dodecyltrimethylammonium chloride, 18-crown-6, and the like.

[0011] Furthermore, in the above technical solution, the reaction temperature is 25-50° C., and the reaction time is 0.5-20 hours.

[0012] Furthermore, in the above technical solution, the molar ratio of the 3-ethyl-3-oxetanol, epichlorohydrin, solid base and phase transfer catalyst is 1:1.1-10:1-5:0.005-0.1.

[0013] Furthermore, in the above technical scheme, epichlorohydrin is added dropwise during the reaction; after the reaction is completed, the mixture is filtered and water is added to the filtrate to remove the dissolved chloride salt and excess solid base generated by the reaction; after stratification, the aqueous phase is extracted with epichlorohydrin, and the organic phase is decompressed to distill off the solvent to obtain EGMA.

[0014] Furthermore, in the above technical solution, in the reduced pressure distillation stage, the excess epichlorohydrin collected is recovered and reused.

[0015] Further, in the above technical scheme, the typical operation process of the present invention is: sodium hydroxide, 3-ethyl-3-oxetane methanol, and a catalyst are added to a four-necked bottle with a mechanical stirrer, and epichlorohydrin is slowly added thereto using a constant pressure dropping funnel, and stirred vigorously. After the epichlorohydrin is added, the temperature is kept for 4-10 hours. Wherein: the molar ratio of 3-ethyl-3-oxetane methanol, epichlorohydrin, sodium hydroxide and phase transfer catalyst is 1:1.1-10:1-5:0.005-0.1.

[0016] The reaction equation is shown as follows:

[0017]

[0018] After the reaction is completed, filter and add an appropriate amount of water to dissolve the sodium chloride and excess sodium hydroxide generated by the reaction. At this time, the organic phase is in the lower layer and the aqueous phase is in the upper layer. Separate the organic phase, and separate and recover the unconsumed epichlorohydrin by vacuum distillation at 38-40mmHg / 80-110℃ with a water pump. Then, perform high vacuum distillation at 4-5mmHg / 110℃ with an oil pump to remove residual epichlorohydrin and high-boiling impurities, and obtain high-purity EGMA product from the kettle residue.

[0019] Beneficial effects of the present invention

[0020] A. The dropwise addition method reduces the generation of side reactions, stabilizes the temperature, and produces a mild reaction. After the reaction is completed, the excess epichlorohydrin can be recycled and reused;

[0021] B. By distilling the solvent, a high-purity, transparent EGMA product with a lower color number can be obtained without evaporating the product. The process is easy to operate and has simple steps, making it suitable for workshop production. DETAILED DESCRIPTION

[0022] The following examples will illustrate the implementation of the present invention, which do not limit the scope of protection of the present invention. The phase transfer catalysts used in the examples: tetrabutylammonium bromide, triethylbenzylammonium chloride, tetramethylammonium chloride, dodecyltrimethylammonium chloride, 18-crown ether-6 were purchased from the market. Typical representative operation

[0023] Example 1

[0024] 24g (0.6mol) of sodium hydroxide is added to a four-necked bottle with mechanical stirring, followed by 0.32g (0.001mol) of tetrabutylammonium bromide and 58g (0.5mol) of 3-ethyl-3-oxabutane methanol. 185g (2mol) of epichlorohydrin is slowly added dropwise through a constant pressure dropping funnel and stirred vigorously. The internal temperature is maintained at 30°C, and after the epichlorohydrin addition is completed, the temperature is kept constant for 9 hours, and the raw material remains 2.5%. Filter by suction, add 62g*3 of water to the filtrate, wash off the residual sodium chloride and sodium hydroxide, separate the organic phase, and extract the aqueous phase with 62g*2 of epichlorohydrin. The organic phases are combined, and the unconsumed epichlorohydrin is separated and recovered by water pump vacuum decompression distillation at 38-40mmHg / 80-110°C. Then, the oil pump was set at 4-5 mmHg / 110-120°C for high vacuum distillation to remove residual epichlorohydrin and high-boiling impurities. 69 g of EGMA product was obtained from the still residue with a content of 91.1%, a yield of 80.2% and a color number of 25.

[0025] Example 2

[0026] Add 24g (0.6mol) of sodium hydroxide to a four-necked bottle with mechanical stirring, followed by 0.32g (0.001mol) of tetrabutylammonium bromide and 58g (0.5mol) of 3-ethyl-3-oxabutane methanol. Slowly add 185g (2mol) of epichlorohydrin through a constant pressure dropping funnel and stir vigorously. Maintain the internal temperature at 40°C, wait until the epichlorohydrin addition is completed, and keep warm for 7h. After the raw material reaction is completed, filter, add 62g*3 of water to the filtrate, wash off the residual sodium chloride and sodium hydroxide, separate the organic phase, and then extract the aqueous phase with 62g*2 of epichlorohydrin, combine the organic phases, and separate and recover the unconsumed epichlorohydrin by water pump vacuum decompression distillation at 38-40mmHg / 80-110°C. Then, the oil pump was used at 4-5 mmHg / 110-120°C for high vacuum distillation to remove residual epichlorohydrin and high-boiling impurities. 78 g of EGMA product was obtained from the still residue, with a content of 95.4%, a yield of 90.7%, and a color number of 30.

[0027] Example 3

[0028] 24g (0.6mol) of sodium hydroxide was added to a four-necked bottle with mechanical stirring, followed by 0.32g (0.001mol) of tetrabutylammonium bromide and 58g (0.5mol) of 3-ethyl-3-oxabutane methanol. 185g (2mol) of epichlorohydrin was slowly added dropwise through a constant pressure dropping funnel and stirred vigorously. The internal temperature was maintained at 50°C, and the addition of epichlorohydrin was completed. The temperature was kept constant for 7 hours. After the raw materials were reacted, the mixture was filtered and 62g*3 of water was added to the filtrate to wash away the residual sodium chloride and sodium hydroxide. The organic phase was separated, and the aqueous phase was extracted with 62g*2 of epichlorohydrin. The organic phases were combined and separated and recovered by vacuum distillation at 38-40mmHg / 80-110°C using a water pump. Subsequently, high vacuum distillation was performed using an oil pump at 4-5 mmHg / 110-120°C to remove residual epichlorohydrin and high-boiling impurities. 75 g of EGMA product was obtained in the kettle, with a content of 93.4%, a yield of 87.2%, and a color number of 35.

[0029] Example 4

[0030] Add 24g (0.6mol) of sodium hydroxide to a four-necked bottle with mechanical stirring, followed by 0.24g (0.001mol) of benzyltriethylammonium chloride and 58g (0.5mol) of 3-ethyl-3-oxabutane methanol. Slowly add 185g (2mol) of epichlorohydrin through a constant pressure dropping funnel and stir vigorously. Keep the internal temperature at 40°C, wait until the addition of epichlorohydrin is completed, and keep warm for 7h. After the raw materials react, filter, add 62g*3 of water to the filtrate, wash off the residual sodium chloride and sodium hydroxide, separate the organic phase, and extract the aqueous phase with 62g*2 of epichlorohydrin. Combine the organic phases, and separate and recover the unconsumed epichlorohydrin by vacuum distillation at 38-40mmHg / 80-110°C with a water pump. Then, the oil pump was used at 4-5 mmHg / 110-120°C for high vacuum distillation to remove residual epichlorohydrin and high-boiling impurities. 77 g of EGMA product was obtained from the still residue, with a content of 94.3%, a yield of 89.5%, and a color number of 20.

[0031] Example 6

[0032] Add 24g (0.6mol) of sodium hydroxide to a four-necked bottle with mechanical stirring, followed by 0.11g (0.001mol) of tetramethylammonium chloride and 58g (0.5mol) of 3-ethyl-3-oxabutane methanol. Slowly add 185g (2mol) of epichlorohydrin through a constant pressure dropping funnel and stir vigorously. Keep the internal temperature at 40°C, wait until the epichlorohydrin addition is completed, and keep warm for 5 hours. After the raw materials react, filter, add 62g*3 of water to the filtrate, wash off the residual sodium chloride and sodium hydroxide, separate the organic phase, and then extract the aqueous phase with 62g*2 of epichlorohydrin, combine the organic phases, and separate and recover the unconsumed epichlorohydrin by water pump vacuum decompression distillation at 38-40mmHg / 80-110°C. Then, the oil pump was used at 4-5 mmHg / 110-120°C for high vacuum distillation to remove residual epichlorohydrin and high-boiling impurities. 82 g of EGMA product was obtained from the still residue, with a content of 96.1%, a yield of 95.3%, and a color number of 10.

[0033] Example 7

[0034] 24g (0.6mol) of sodium hydroxide was added to a four-necked bottle with mechanical stirring, followed by 0.26g (0.001mol) of dodecyltrimethylammonium chloride and 58g (0.5mol) of 3-ethyl-3-oxabutane methanol. 185g (2mol) of epichlorohydrin was slowly added dropwise through a constant pressure dropping funnel, and stirred vigorously. Maintaining the internal temperature at 40°C, 185g (2mol) of epichlorohydrin was slowly added dropwise, and stirred vigorously. Maintaining the internal temperature at 50°C, after the epichlorohydrin addition was completed, the temperature was kept constant for 9h. After the raw materials were reacted, the filtrate was filtered, 62g*3 of water was added to the filtrate, residual sodium chloride and sodium hydroxide were washed off, the organic phase was separated, and the aqueous phase was extracted with 62g*2 of epichlorohydrin, the organic phases were combined, and the unconsumed epichlorohydrin was separated and recovered by water pump vacuum decompression distillation at 38-40mmHg / 80-110°C. Then, the oil pump was used at 4-5 mmHg / 110-120°C for high vacuum distillation to remove residual epichlorohydrin and high-boiling impurities. 71 g of EGMA product was obtained from the still residue, with a content of 93.2%, a yield of 82.6%, and a color number of 15.

[0035] Example 8

[0036] Add 24g (0.6mol) of sodium hydroxide to a four-necked bottle with mechanical stirring, followed by 60.26g (0.001mol) of 18-crown ether and 58g (0.5mol) of 3-ethyl-3-oxabutane methanol. Slowly add 185g (2mol) of epichlorohydrin through a constant pressure dropping funnel and stir vigorously. Keep the internal temperature at 40°C, wait until the addition of epichlorohydrin is completed, and keep warm for 10 hours. After the raw materials react, filter, add 62g*3 of water to the filtrate, wash off the residual sodium chloride and sodium hydroxide, separate the organic phase, and extract the aqueous phase with 62g*2 of epichlorohydrin. Combine the organic phases, and separate and recover the unconsumed epichlorohydrin by water pump vacuum decompression distillation at 38-40mmHg / 80-110°C. Then, the oil pump was used at 4-5 mmHg / 110-120°C for high vacuum distillation to remove residual epichlorohydrin and high-boiling impurities. 63 g of EGMA product was obtained from the still residue, with a content of 90.2%, a yield of 73.3%, and a color number of 40.

[0037] Example 9

[0038] Add 32.4g (0.6mol) of sodium methoxide to a four-necked bottle with mechanical stirring, followed by 0.11g (0.001mol) of tetramethylammonium chloride and 58g (0.5mol) of 3-ethyl-3-oxabutane methanol. Slowly add 185g (2mol) of epichlorohydrin through a constant pressure dropping funnel and stir vigorously. Maintain the internal temperature at 40°C, wait until the addition of epichlorohydrin is completed, and keep warm for 6 hours. After the raw materials react, filter, add 62g*3 of water to the filtrate, wash off the residual sodium chloride, sodium methoxide and methanol, separate the organic phase, and extract the aqueous phase with 62g*2 of epichlorohydrin. Combine the organic phases, and separate and recover the unconsumed epichlorohydrin by vacuum distillation at 38-40mmHg / 80-110°C with a water pump. Then, the oil pump was used at 4-5 mmHg / 110-120°C for high vacuum distillation to remove residual epichlorohydrin and high-boiling impurities. 73 g of EGMA product was obtained from the still residue, with a content of 92.3%, a yield of 84.9%, and a color number of 40.

[0039] Example 10

[0040] Add 40.8g (0.6mol) of sodium ethoxide to a four-necked bottle with mechanical stirring, followed by 0.11g (0.001mol) of tetramethylammonium chloride and 58g (0.5mol) of 3-ethyl-3-oxabutane methanol. Slowly add 185g (2mol) of epichlorohydrin through a constant pressure dropping funnel and stir vigorously. Maintain the internal temperature at 40°C, wait until the addition of epichlorohydrin is completed, and keep warm for 6 hours. After the raw materials react, filter, add 62g*3 of water to the filtrate, wash off the residual sodium chloride, sodium ethoxide and ethanol, separate the organic phase, and extract the aqueous phase with 62g*2 of epichlorohydrin. Combine the organic phases, and separate and recover the unconsumed epichlorohydrin by vacuum distillation at 38-40mmHg / 80-110°C with a water pump. Then, the oil pump was used at 4-5 mmHg / 110-120°C for high vacuum distillation to remove residual epichlorohydrin and high-boiling impurities. 71 g of EGMA product was obtained from the still residue, with a content of 90.8%, a yield of 82.6%, and a color number of 40.

[0041] Embodiment 11

[0042] Add 33.6g (0.6mol) of potassium hydroxide to a four-necked bottle with mechanical stirring, and then add 0.11g (0.001mol) of tetramethylammonium chloride and 58g (0.5mol) of 3-ethyl-3-oxabutane methanol. Slowly add 185g (2mol) of epichlorohydrin through a constant pressure dropping funnel and stir vigorously. Keep the internal temperature at 40°C, wait until the addition of epichlorohydrin is finished, and keep warm for 6h. After the raw materials react, filter, add 62g*3 of water to the filtrate, wash off the residual potassium chloride and potassium hydroxide, separate the organic phase, and then extract the aqueous phase with 62g*2 of epichlorohydrin, combine the organic phases, and separate and recover the unconsumed epichlorohydrin by water pump vacuum decompression distillation at 38-40mmHg / 80-110°C. Then, the oil pump was used at 4-5 mmHg / 110-120°C for high vacuum distillation to remove residual epichlorohydrin and high-boiling impurities. 79 g of EGMA product was obtained from the still residue, with a content of 93.2%, a yield of 91.9%, and a color number of 20.

[0043] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A method for synthesizing 3-ethyl-3-[(2-oxiranylmethoxy)methyl]oxetane EGMO, characterized in that: The method comprises the following steps: taking 3-ethyl-3-oxetane methanol and epichlorohydrin as raw materials, reacting under the action of a solid base and a phase transfer catalyst to obtain 3-ethyl-3-[(2-oxiranylmethoxy)methyl]oxetane.

2. The method for synthesizing 3-ethyl-3-[(2-oxiranylmethoxy)methyl]oxetane according to claim 1, characterized in that: The solid base is selected from sodium methoxide, sodium ethoxide, sodium hydroxide or potassium hydroxide.

3. The method for synthesizing 3-ethyl-3-[(2-oxiranylmethoxy)methyl]oxetane according to claim 1, characterized in that: The phase transfer catalyst is selected from tetrabutylammonium bromide, triethylbenzylammonium bromide, tetramethylammonium chloride, dodecyltrimethylammonium chloride or 18-crown-6.

4. The method for synthesizing 3-ethyl-3-[(2-oxiranylmethoxy)methyl]oxetane according to claim 1, characterized in that: The reaction temperature is 25-50°C, and the reaction time is 0.5-20 hours.

5. The method for synthesizing 3-ethyl-3-[(2-oxiranylmethoxy)methyl]oxetane according to claim 1, characterized in that: The molar ratio of the 3-ethyl-3-oxetanol, epichlorohydrin, solid base and phase transfer catalyst is 1:1.1-10:1-5:0.005-0.

1.

6. The method for synthesizing 3-ethyl-3-[(2-oxiranylmethoxy)methyl]oxetane according to claim 1, characterized in that: During the reaction, epichlorohydrin is added dropwise while the reaction is carried out to control the reaction temperature; after the reaction is completed and filtered, water is added to the organic phase to remove the chloride salt generated by the reaction and the residual solid alkali; after stratification, the organic phase is distilled under reduced pressure, and the residue in the kettle is 3-ethyl-3-[(2-oxiranylmethoxy)methyl]oxetane with a higher content and a lower color number.

7. The method for synthesizing 3-ethyl-3-[(2-oxiranylmethoxy)methyl]oxetane according to claim 6, characterized in that: In the distillation process, the reduced pressure distillation stage is divided into two processes: collecting epichlorohydrin and collecting a small amount of epichlorohydrin and high-boiling impurities remaining in the system.

8. The method for preparing 3-ethyl-3-[(2-oxiranylmethoxy)methyl]oxetane according to claim 7, characterized in that: During the vacuum distillation stage, the excess epichlorohydrin collected is recovered and reused.

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