Method for producing alkylalkenyl ethers

Abstract

This invention provides a method for producing alkyl alkenyl ethers with good reactivity as a resin modifier, without the use of organic solvents, and in high yield and high purity. [Solution] A method for producing an alkyl alkenyl ether represented by the following formula (1) is provided, characterized by comprising the following steps (A), (B), (C), and (D). R 1 -OR 2 ...(1) Step (A): A step in which an alkyl alcohol is etherified with an alkenyl chloride; Step (B): The reaction mixture obtained in step (A) is washed with water and dehydrated under inert gas bubbling; Step (C): A step in which alkenyl chloride is added to the mixture obtained in step (B) to carry out an etherification reaction; and Step (D): The reaction mixture obtained in step (C) is washed with water, dehydrated under inert gas bubbling, and then treated with an inorganic adsorbent.

Description

[Technical Field]

[0001] This invention relates to a method for producing alkylalkenyl ethers. [Background technology]

[0002] Alkyl allyl ethers are useful as resin modifiers for introduction into resin skeletons because they possess a reactive alkenyl group and their lipophilicity can be adjusted by the alkyl group. Specifically, they are used as silicone modifiers and copolymer monomers.

[0003] In Patent Document 1, a method for synthesizing such alkyl allyl ethers involves reacting an alkyl alcohol with an alkenyl halogen under basic conditions, followed by column purification using a solvent to improve purity and obtain a highly pure alkyl alkenyl ether with impurities removed. However, obtaining a large quantity of the target product through column purification requires large-scale purification equipment, and the time required from purification to recovery of the target product is long, resulting in a low yield. Therefore, this method has limitations as an industrial production method. In addition, from the perspective of environmental impact in recent years, there has been a demand for products and manufacturing processes that do not use solvents.

[0004] Against this backdrop, Patent Document 2 describes how alkyl allyl ethers are obtained in high yield by adding water after etherification, extracting the resulting sodium chloride, and then removing the aqueous phase. However, extraction with only a small amount of water may not be sufficient to remove all of the sodium chloride, which could inhibit the reaction when used as a resin modifier, posing a challenge in meeting the demands for high performance in recent years. Furthermore, in this synthesis method, unreacted alkyl alcohol may be present at a concentration of 10% or more, requiring the addition of approximately 10-20% excess allyl halogen to carry out the reaction. Even in this case, there is still a high possibility that unreacted alkyl alcohol will remain in the final product, leading to performance degradation.

[0005] Furthermore, Patent Document 3 reports that allyl compounds can be obtained in relatively high yield by using a metal oxide catalyst in which a molybdenum oxide film is formed on the surface of titania and / or zirconia, and by reacting allyl alcohol with compounds such as alcohols and phenols to carry out a dehydration reaction. However, when alkyl alcohols with a long number of carbon atoms are used as raw materials, the same effect cannot be obtained due to reactivity, and it may not be possible to meet the high purity requirements for electronic materials applications, thus presenting the challenge of not being able to achieve both high yield and high purity. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] Japanese Unexamined Patent Publication No. 56-25160 [Patent Document 2] CN102942459 [Patent Document 3] Japanese Patent Publication No. 2019-85359 [Overview of the project] [Problems that the invention aims to solve]

[0007] Thus, there was a need for a method to produce alkyl alkenyl ethers with good reactivity as a resin modifier, without the use of organic solvents, and in high yield and high purity.

[0008] Furthermore, during the development of the present invention, it was reported that a method for producing alkenyl group-containing polyoxyalkylene derivatives involves washing with water followed by neutralization with phosphoric acid or the like, thereby removing residual alkali and generated alkali halides, and obtaining alkenyl group-containing polyoxyalkylene derivatives with good reactivity as resin modifiers (for example, Japanese Patent Application Publication No. 2007-204701). However, alkylalkenyl ethers have significantly different polarity compared to alkenyl group-containing polyoxyalkylene derivatives and are not easily miscible with neutralizing agents such as phosphoric acid. As a result, residual metal components cannot be sufficiently removed, which may lead to a decrease in reactivity with resins. [Means for solving the problem]

[0009] As a result of diligent research to solve the above problems, the inventors have discovered a manufacturing method that allows for the production of alkyl alkenyl ethers in high purity and high yield without the use of organic solvents, using a specific manufacturing method. The present invention provides the following manufacturing method. [1] A method for producing an alkyl alkenyl ether represented by the following formula (1), characterized by comprising the steps (A), (B), (C), and (D) below; R 1 -OR 2 ...(1) (In formula (1), R 1 R represents an alkyl group having 6 to 36 carbon atoms. 2 This indicates an alkenyl group with 3 to 5 carbon atoms. Step (A): Alkyl alcohol (R 1 -OH) is dissolved in 1.0 to 1.5 molar equivalents of alkenyl chloride (R) in the presence of 1.5 to 3.0 molar equivalents of alkali relative to the alkyl alcohol. 2 A step in which the etherification reaction is carried out with -Cl); Step (B): The reaction mixture obtained in Step (A) is washed with 10 to 20 molar equivalents of water relative to the alkali used in Step (A), and then dehydrated under inert gas bubbling; Step (C): To the mixture obtained in Step (B), 0.5 to 1.2 molar equivalents of alkali and 0.3 to 0.8 molar equivalents of the same alkenyl chloride used in Step (A) are added relative to the alkyl alcohol used in Step (A) to carry out the etherification reaction; and Step (D): The reaction mixture obtained in Step (C) is washed with 20 to 50 molar equivalents of water with the alkali used in Step (C), then dehydrated under inert gas bubbling, and further treated under an inert gas atmosphere with an inorganic adsorbent containing at least one oxide and hydroxide of one or more elements selected from the group consisting of magnesium, silicon, and aluminum, using 0.5 to 2.0 parts by weight per 100 parts by weight of the alkyl alcohol used in Step (A). [Effects of the Invention]

[0010] According to the manufacturing method of the present invention, alkyl alkenyl ethers can be obtained with good reactivity as resin modifiers, without the use of organic solvents, in high yield and with high purity. [Modes for carrying out the invention]

[0011] The present invention will be described in detail below. In equation (1), R 1 This represents an alkyl group having 6 to 36 carbon atoms. In this specification, the "alkyl group having 6 to 36 carbon atoms" may be linear or branched, and examples include hexyl group, octyl group, nonyl group, isononyl group, decyl group, undecyl group, dodecyl group, tridecyl group, isotridecyl group, tetradecyl group, hexadecyl group, isocetyl group, octadecyl group, isostearyl group, eicosyl group, docosyl group, tetracosyl group, hexatriacontyl group, decyltetradecyl group, etc. Preferably, it is an alkyl group having 10 to 32 carbon atoms.

[0012] In equation (1), R2 represents an alkenyl group having 3 to 5 carbon atoms. In this specification, the "alkenyl group having 3 to 5 carbon atoms" may be linear or branched, and may also contain two or more double bonds. For example, alkenyl groups such as allyl group, 3-butenyl group, methallyl group, 2-methyl-3-butenyl group, 3-methyl-3-butenyl group, 1,1-dimethyl-2-propenyl group, 4-pentenyl group, etc. can be mentioned. In one embodiment, it is preferably an allyl group. In another embodiment, it is preferably an allyl group or a methallyl group.

[0013] Hereinafter, the production method of the present invention will be described in detail. The alkyl alkenyl ether represented by the following formula (1) is produced by a method including the following steps (A), (B), (C) and (D). R 1 -OR 2 ····(1) (In formula (1), R 1 represents an alkyl group having 6 to 36 carbon atoms, and R 2 represents an alkenyl group having 3 to 5 carbon atoms.)

[0014] Project (A) Step (A) is a step of subjecting an alkyl alcohol (R 1 -OH) to an etherification reaction with 1.0 to 1.5 molar equivalents of an alkenyl chloride (R 2 -Cl) in the presence of 1.5 to 3.0 molar equivalents of an alkali with respect to the alkyl alcohol.

[0015] Examples of the alkyl alcohol used in this step include alcohols corresponding to R 1 described above, such as dodecyl alcohol, octadecyl alcohol, isostearyl alcohol, tetracosyl alcohol, decyltetradecyl alcohol, hexatriacontyl alcohol, etc. Examples of the alkenyl chloride used in this step include those corresponding to R 2Examples of chlorides are listed. In one embodiment, allyl chloride is particularly preferred. In another embodiment, allyl chloride or methallyl chloride is particularly preferred. The amount used is 1.0 to 1.5 molar equivalents relative to the alkyl alcohol. If the amount used is less than the above range, the yield and purity will decrease, and conversely, if it is more, the economic efficiency will be poor. Alkenyl chloride is preferably used in an amount of 1.0 to 1.4 molar equivalents, more preferably 1.0 to 1.3 molar equivalents.

[0016] Examples of alkalis used in this process include alkali metal hydroxides such as potassium hydroxide, sodium hydroxide, lithium hydroxide, and cesium hydroxide. Potassium hydroxide or sodium hydroxide is preferably used, and potassium hydroxide is particularly preferred. The amount used is 1.5 to 3.0 molar equivalents relative to the alkyl alcohol. If the amount used is less than the above range, the yield and purity will decrease, while if it is more, the economic efficiency will be poor. Preferably, 1.5 to 2.8 molar equivalents of alkali are used, more preferably 1.8 to 2.6 molar equivalents.

[0017] The etherification reaction is carried out by mixing an alkyl alcohol, an alkenyl chloride, and an alkali, but from the viewpoint of reactivity, it is preferable to add the alkenyl chloride and alkali to the alkyl alcohol. Etherification reactions are typically carried out under nitrogen conditions and without a solvent. The etherification reaction is typically carried out at a temperature of 70 to 130°C, preferably between 80 and 120°C, from the viewpoint of reaction progress and suppression of by-products. The reaction time depends on the type of alkyl alcohol or alkenyl chloride and the reaction temperature, but is usually 1 to 6 hours, preferably 1 to 4 hours. The progress of the reaction can be confirmed by NMR or other methods.

[0018] Project (B) Step (B) involves washing the reaction mixture obtained in step (A) with 10 to 20 molar equivalents of water relative to the alkali used in step (A), and then dehydrating it under inert gas bubbling.

[0019] The reaction mixture obtained in step (A) contains unreacted alkyl alcohols and alkenyl chlorides, as well as excess alkali. Furthermore, the reaction mixture also contains alkali chlorides generated during the reaction. In this step, residual alkali and alkenyl chlorides, as well as the generated alkali chlorides, are removed by washing with water. Specifically, water is added to the reaction mixture obtained in step (A) and stirred to extract the residual alkali and alkali chlorides into the aqueous phase. After standing and phase separation, this aqueous phase is removed. In this washing process, 10 to 20 molar equivalents of water are used relative to the alkali used in step (A). If the amount used is less than the above range, emulsification will occur, reducing the yield. Conversely, if the amount used is too much, the difference in specific gravity between water and the target substance becomes small, making phase separation difficult and reducing the yield. Therefore, preferably 10 to 18 molar equivalents, and more preferably 11 to 16 molar equivalents, are used. Stirring is typically done at a temperature of 60-90°C for 5 minutes to 1 hour, and standing is typically done at a temperature of 60-90°C for 1 to 5 hours. The above washing is important for the etherification reaction in step (C), and without this washing, the etherification reaction in step (C) will not proceed sufficiently.

[0020] Since the mixture after washing contains water, it is dehydrated under inert gas bubbling. Examples of inert gases include nitrogen and argon, with nitrogen being preferred due to its availability. Dehydration is typically carried out under inert gas bubbling and stirring at a temperature of 70 to 130°C, preferably 100 to 120°C, for 30 minutes to 5 hours, preferably 1 to 3 hours. Dehydration can also be carried out under atmospheric pressure or vacuum conditions.

[0021] Any remaining unreacted alkenyl chloride can be removed by the washing described above, but it can also be removed before washing by bubbling with an inert gas (for example, nitrogen gas) at a temperature of 70-100°C for 30 minutes to 2 hours.

[0022] Project (C) Step (C) is a step in which etherification is carried out by adding 0.5 to 1.2 molar equivalents of alkali and 0.3 to 0.8 molar equivalents of the same alkenyl chloride used in step (A) to the mixture obtained in step (B), relative to the alkyl alcohol used in step (A).

[0023] The mixture obtained in step (B) contains unreacted alkyl alcohol, so alkali and alkenyl chloride are added to it to etherify it. The same alkenyl chloride used in step (A) is used. The amount used is the amount necessary to ensure sufficient etherification, which is 0.3 to 0.8 molar equivalents relative to the alkyl alcohol used in step (A). If the amount used is less than the above range, the yield and purity will decrease, and conversely, if it is more, the economic efficiency will be poor. Preferably, 0.3 to 0.7 molar equivalents, more preferably 0.3 to 0.6 molar equivalents of alkenyl chloride are used.

[0024] The alkali used is preferably the same alkali used in step (A). The amount used is the amount necessary to ensure sufficient etherification, which is 0.5 to 1.2 molar equivalents relative to the alkyl alcohol used in step (A). If the amount used is less than the above range, the yield and purity will decrease, while if it is more, the economic efficiency will be poor. Preferably, 0.6 to 1.2 molar equivalents, and more preferably 0.6 to 1.1 molar equivalents, of the alkali is used.

[0025] Etherification reactions are typically carried out under nitrogen conditions and without a solvent. The etherification reaction is typically carried out at a temperature of 70 to 130°C, preferably between 80 and 120°C, from the viewpoint of reaction progress and suppression of by-products. The reaction time depends on the type of alkyl alcohol or alkenyl chloride and the reaction temperature, but is usually 1 to 6 hours, preferably 1 to 4 hours. The progress of the reaction can be confirmed by NMR or other methods.

[0026] Engineering (D) Step (D) involves washing the reaction mixture obtained in step (C) with 20 to 50 molar equivalents of water against the alkali used in step (C), then dehydrating it under inert gas bubbling, and finally treating it under an inert gas atmosphere with an inorganic adsorbent containing at least one oxide and hydroxide of one or more elements selected from the group consisting of magnesium, silicon, and aluminum, using 0.5 to 2.0 parts by weight per 100 parts by weight of the alkyl alcohol used in step (A).

[0027] The reaction mixture obtained in step (C) contains residual alkali and generated alkali chloride. These are removed in this step by washing with water. Specifically, this is done using the same procedure as described in step (B). Removal of these improves the yield of the target product. In this washing process, 20 to 50 molar equivalents of water are used relative to the alkali used in step (C). If the amount used is less than the above range, emulsification will occur, reducing the yield. Conversely, if the amount used is too much, the difference in specific gravity between water and the target substance will be small, making phase separation difficult and reducing the yield. Preferably, 25 to 50 molar equivalents of water are used, more preferably 30 to 45 molar equivalents. Regarding the relationship between alkyl alcohol and water, 15 to 45 molar equivalents of water are used relative to the alkyl alcohol used in step (A). Preferably, 20 to 40 molar equivalents of water are used, more preferably 20 to 35 molar equivalents. Stirring is typically done at a temperature of 60-90°C for 5 minutes to 1 hour, and standing is typically done at a temperature of 60-90°C for 1 to 5 hours.

[0028] Since the mixture after washing contains water, it is dehydrated under inert gas bubbling. Examples of inert gases include nitrogen and argon, with nitrogen being preferred due to its availability. Dehydration is typically carried out under inert gas bubbling and stirring at a temperature of 70 to 130°C, preferably 100 to 120°C, for 30 minutes to 5 hours, preferably 1 to 3 hours. Dehydration can also be carried out under atmospheric pressure or vacuum conditions. If unreacted alkenyl chloride remains in the reaction mixture obtained in step (C), it can be removed by the washing described above. Alternatively, it can be removed under inert gas bubbling before the washing, using the same procedure as in step (B).

[0029] The mixture after water removal contains trace amounts of metals (e.g., alkali metals), which are removed by treatment with an adsorbent. Metal removal is important for its application as a silicone modifier. As the adsorbent, an inorganic adsorbent containing at least one oxide and hydroxide of one or more elements selected from the group consisting of magnesium, silicon, and aluminum is used. In particular, an inorganic adsorbent containing at least one element selected from the group consisting of magnesium oxide, aluminum oxide, silicon dioxide, magnesium hydroxide, and aluminum hydroxide is preferably used. Examples of such inorganic adsorbents include activated clay, synthetic zeolite, activated alumina, Siligel, magnesia, and commercially available synthetic adsorbents such as Kyoward 100, Kyoward 200, Kyoward 300, Kyoward 400, Kyoward 500, Kyoward 600, Kyoward 700, Kyoward 1000, Kyoward 2000 (manufactured by Kyowa Chemical Industry Co., Ltd.), Tomix AD100, Tomix AD200, Tomix AD300, Tomix AD400, Tomix AD500, Tomix AD600, Tomix AD700, and Tomix AD800 (manufactured by Tomita Pharmaceutical Co., Ltd.).

[0030] The inorganic adsorbent is used in an amount of 0.5 to 2.0 parts by weight per 100 parts by weight of alkyl alcohol used in step (A). If the amount used is less than the above range, the adsorption and removal of trace metals will be insufficient, and conversely, if it is more, the adsorption capacity will not improve and the filtration efficiency will decrease. Preferably, 0.8 to 1.5 parts by weight of the inorganic adsorbent is used. In addition, the treatment may be carried out using multiple inorganic adsorbents.

[0031] The adsorption treatment can be carried out by known methods. For example, the adsorption treatment can be performed for 20 minutes to 3 hours, preferably 30 minutes to 2 hours, at a temperature in the range of 70 to 90°C, preferably 80 to 90°C, while blowing in an inert gas. The adsorption treatment can also be carried out under atmospheric pressure, under pressurized pressure, or under vacuum conditions. Furthermore, the adsorption treatment may be carried out with stirring. After the adsorption treatment, the adsorbent is removed by filtration. Filtration is preferably performed under pressure or reduced pressure, and may be repeated until the solution becomes clear.

[0032] Alkyl alkenyl ethers represented by formula (1), from which metals (e.g., alkali metals) have been removed through such adsorption treatment, are fully usable as resin modifiers, particularly silicone modifiers, as well as pharmaceutical raw materials.

[0033] By the above manufacturing method, the alkyl alkenyl ether represented by formula (1) can be obtained in a yield of 75% or more, and especially 80% or more. The alkyl alkenyl ether represented by the obtained formula (1) has a purity of 85% or more, particularly 90% or more, and a metal (e.g., alkali metal) content of 50 ppm or less, particularly 10 ppm or less, making it suitable for use as a resin modifier or pharmaceutical raw material. [Examples]

[0034] The present invention will be described in more detail below with reference to synthesis examples, examples, and comparative examples, but the present invention is not limited in any way to these examples. The synthetic products were analyzed by the method shown below.

[0035] The hydroxyl value was measured as follows: A specified amount of sample and 25 ml of pyridine solution of phthalic anhydride were added to an esterification flask, a stopper was attached, and the flask was heated in a constant temperature bath at 98°C for 2 hours, with occasional gentle shaking. Next, the flask was removed from the constant temperature bath and allowed to stand at room temperature. After removing the stopper and washing with pyridine, 50 ml of 0.5 mol / L sodium hydroxide solution and 10 drops of pyridine solution of phenolphthalein were added, and the flask was titrated with 0.5 mol / L sodium hydroxide solution.

[0036] The purity was calculated using the following formula. Purity (%) = 100 × (1 - ((Hydroxyl value of etherified product (after etherification) / (Hydroxyl value of raw material alcohol (before etherification))))

[0037] The yield was calculated using the following formula. Yield (%) = 100 × (Yield of etherified product) / (Amount of raw alcohol used)

[0038] The potassium (K) content was measured as follows: A specified amount of sample was weighed into a platinum dish and completely burned to ash using a gas burner. The ash was placed in a 50 ml volumetric flask and dissolved by making up the volume with purified water. The potassium content in the test solution was determined using an atomic absorption spectrometer and a calibration curve of standard solutions.

[0039] [Example 1] 500g of dodecyl alcohol (C12) (manufactured by Kanto Chemical Co., Ltd.), 302g of potassium hydroxide, and 234g of allyl chloride were charged into a 5-liter autoclave. After purging with nitrogen, the reaction was carried out at 120°C for 3 hours. After the reaction was complete, unreacted allyl chloride was removed by nitrogen bubbling at 80°C and below -0.097 MPa (gauge pressure) for 1 hour. 1209g of water was added, stirred at 80°C for 10 minutes, and then allowed to stand at 80°C for 1 hour. The separated upper layer was collected and treated at 110°C and below -0.097 MPa (gauge pressure) with nitrogen bubbling for 2 hours. 101g of potassium hydroxide and 79g of allyl chloride were then charged into the autoclave. After purging with nitrogen, the reaction was carried out at 120°C for 2 hours. After the reaction was complete, unreacted allyl chloride was removed by nitrogen bubbling at 80°C and -0.097 MPa (gauge pressure) or less for 1 hour. 1209 g of water was added, stirred at 80°C for 10 minutes, and then allowed to stand at 80°C for 1 hour. The separated upper layer was collected and treated at 110°C and -0.097 MPa (gauge pressure) or less by nitrogen bubbling for 2 hours. Subsequently, 2.5 g each of Kyoward 1000 and Kyoward 700 (manufactured by Kyowa Chemical Industry Co., Ltd.) were added, and adsorption treatment was carried out at 80°C and -0.097 MPa (gauge pressure) or less by nitrogen bubbling for 1 hour. Filter paper was set in a filter, and filtration was performed to obtain 460 g of allyl ether. The physical properties of the obtained allyl ether were a hydroxyl value of 7, purity of 98%, potassium content of 1.2 ppm, and yield of 92%.

[0040] [Examples 2-5] Allyl etherification was carried out in the same manner as in Example 1, using the raw materials and quantities shown in Table 1.

[0041] [Examples 6 and 7] Using metharyl chloride instead of allyl chloride, metharyl etherification was performed in the same manner as in Example 1, with the raw materials and amounts shown in Table 1.

[0042] [Comparative Example 1] Allyl etherification was carried out in the same manner as in Example 1, using the raw materials and quantities shown in Table 1. However, washing in steps (C) and (D) was omitted.

[0043] [Comparative Example 2] Allyl etherification was carried out in the same manner as in Example 1, using the raw materials and quantities shown in Table 1.

[0044] [Comparative Example 3] Allyl etherification was carried out in the same manner as in Example 1, using the raw materials and quantities shown in Table 1. However, the adsorption treatment in step (D) was omitted.

[0045] [Comparative Example 4] Allyl etherification was carried out in the same manner as in Example 1, using the raw materials and quantities shown in Table 1. However, steps (C) and (D) were omitted.

[0046] The reactivity of the etherified products (allyl etherified or methallyl etherified) obtained in Examples 1-7 and Comparative Examples 1-4 with silicone was evaluated using the following method. A 300 ml four-necked flask equipped with a stirrer, nitrogen blowing tube, thermocouple, and condenser was charged with 100 g of hydrogen dimethylpolysiloxane (HMS-082 (manufactured by Gelest), SiH equivalent per gram: 1.06 meq / g) (SiH equivalent: 106 meq) and 34 g of the resulting etherified product (unsaturated equivalent: 148 meq), and an isopropyl alcohol solution of hexahydrate chloroplatinic acid (1 × 10⁻¹⁰ -3 The mixture was prepared to a concentration of 100 ppm (moles / liter) equivalent to platinum, and the reaction was carried out at 90°C under a nitrogen atmosphere with stirring. The time it took for the reaction to proceed and the solution to become homogeneous was measured, and the results were evaluated under the following conditions. It takes less than 1 minute until it becomes uniform: ◎ Take less than 5 minutes until uniform: ○ If it takes more than 30 minutes to become uniform, or if it does not become uniform: △

[0047] Table 1 shows the conditions for steps (A) to (D) in Examples 1 to 7 and Comparative Examples 1 to 4, as well as the purity, hydroxyl value before and after etherification, yield, K content, and reactivity to silicone of the obtained etherified products. In the table, C12 represents a dodecyl group, C18 represents an isostearyl group, C24 represents a decyltetradecyl group, and C36 represents a hexatriacontyl group.

[0048] [Table 1]

[0049] Table 1 shows that in Examples 1 to 7, allyl ether or methallyl ether with high purity and low potassium content can be produced with good yield, and that the reactivity with silicone is also good.

[0050] On the other hand, in Comparative Example 1, the purity of the allyl ether was low because step (C) was not performed. In Comparative Example 2, the yield of allyl ether was low because the amount of water used during the washing process (D) was small. In Comparative Example 3, the amount of water used during the rinsing process (D) was small, resulting in a low yield of allyl ether. Furthermore, because the adsorption treatment in process (D) was not performed, the potassium content was high, and the reactivity to silicone was insufficient. In Comparative Example 4, although a large amount of allyl chloride was charged in step (A), step (C) was not performed, resulting in low purity of the allyl ether. Furthermore, because the adsorption treatment in step (D) was not performed, the potassium content was high, and the reactivity to silicone was insufficient. [Industrial applicability]

[0051] According to the manufacturing method of the present invention, alkyl alkenyl ethers can be obtained with good reactivity as resin modifiers, without the use of organic solvents, in high yield and with high purity.

Claims

[Claim 1] A method for producing an alkyl alkenyl ether represented by the following formula (1), characterized by comprising the following steps (A), (B), (C), and (D); R １ -OR ２ ・・・・(1) (In formula (1), R １ R represents an alkyl group having 6 to 36 carbon atoms. ２ (This indicates an alkenyl group with 3 to 5 carbon atoms.) Step (A): Alkyl alcohol (R １ -OH) is dissolved in 1.0 to 1.5 molar equivalents of alkenyl chloride (R) in the presence of 1.5 to 3.0 molar equivalents of alkali relative to the alkyl alcohol. ２ A step in which an etherification reaction is carried out with -Cl; Step (B): The reaction mixture obtained in Step (A) is washed with 10 to 20 molar equivalents of water relative to the alkali used in Step (A), and then dehydrated under inert gas bubbling; Step (C): To the mixture obtained in Step (B), 0.5 to 1.2 molar equivalents of alkali and 0.3 to 0.8 molar equivalents of the same alkenyl chloride used in Step (A) are added relative to the alkyl alcohol used in Step (A) to carry out the etherification reaction; and Step (D): The reaction mixture obtained in Step (C) is washed with 20 to 50 molar equivalents of water with the alkali used in Step (C), then dehydrated under inert gas bubbling, and further treated under an inert gas atmosphere with an inorganic adsorbent containing at least one oxide and hydroxide of one or more elements selected from the group consisting of magnesium, silicon, and aluminum, in an amount of 0.5 to 2.0 parts by weight per 100 parts by weight of the alkyl alcohol used in Step (A).

Images