JP2010180148A - Method for producing n-glycidyl phthalimide - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing high purity N-glycidyl phthalimide with industrially high productivity in a high yield. <P>SOLUTION: The method for producing the N-glycidyl phthalimide by reacting epichlorohydrin with a phthalimide alkali salt comprises reacting (1) the phthalimide alkali salt with 4-50 mol times the epichlorohydrin (2) in the presence of a quaternary ammonium salt and/or a quaternary phosphonium salt and (3) at a reaction temperature of 40-100°C. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method for producing N-glycidylphthalimide, which is an industrially useful epoxy compound.

  N-Glycidylphthalimide is a compound widely used in the fields of organic chemistry and polymer chemistry, and is a useful compound in a wide range of industrial applications such as fine chemicals, raw materials for medical and agricultural chemicals and resin materials, and electronic information materials and optical materials. It is.

  Furthermore, N-glycidyl phthalimide is mixed with a polyfunctional epoxy compound and cured with various curing agents, so that a cured product generally excellent in mechanical properties, water resistance, chemical resistance, heat resistance and electrical properties. Thus, the cured product is used in a wide range of fields such as adhesives, paints, laminates, composite materials with glass fibers, carbon fibers, and the like.

  Conventionally, as a method for producing N-glycidylphthalimide by reacting phthalimide or an alkali salt thereof with epichlorohydrin, a method of refluxing phthalimide or potassium phthalimide in the presence of excess epichlorohydrin has been proposed. (See Patent Document 1 and Non-Patent Documents 1 and 2.) However, in this method, the yield is not sufficient, and since the reaction is further performed at a high temperature of 120 ° C. or more for a long time, the N-glycidyl phthalimide produced by the reaction further reacts with the raw material potassium phthalimide, and the dimer There is a problem that 2,2 ′-(2-hydroxypropane-1,3-diyl) bis (2H-isoindole-1,3-dione) as a by-product is remarkably by-produced. This by-product is not easily separated from the target product, and the purification operation is complicated in order to obtain high-purity N-glycidylphthalimide.

  In addition, a method of reacting in a short time using microwaves in the presence of tetra-n-butylammonium bromide and potassium carbonate has been proposed (see Non-Patent Document 3). However, in this method, in addition to the low yield, the use of microwaves is not an industrial manufacturing method.

  In addition, a method of reacting potassium phthalimide and epihalohydrin in equal amounts in a DMF solvent has been proposed (see Patent Document 2 and Non-Patent Document 4). However, even in this method, the dimer 2,2 ′-(2-hydroxypropane-1,3-diyl) bis (2H-isoindole-1,3-dione) is remarkably by-produced. There is.

  Moreover, a method of reacting phthalimide and epichlorohydrin in an ionic liquid in the presence of potassium fluoride has been proposed (see Non-Patent Document 5). However, although this method has a high yield, the ionic liquid is extremely expensive, and it is difficult to say that it is an industrial method.

  Furthermore, a method in which an alkali salt of phthalimide and epichlorohydrin are reacted in an alcohol solvent, or an alkali metal carbonate, alkali metal hydrogen carbonate or quaternary ammonium salt in an organic solvent with phthalimide and epichlorohydrin. A two-stage method is proposed in which N- (3-halo-2-hydroxypropyl) phthalimide is reacted in the presence to obtain cyclization with an alkali metal alkoxide (see Patent Document 3). However, since this method has a low reaction rate and requires a long time to complete the reaction, a more efficient production method has been desired. In addition, N- (3-halo-2-hydroxypropyl) phthalimide, which is an intermediate, remains, and in the step of isolation from the reaction solution, N-glycidylphthalimide is obtained by a concentration operation or a water washing operation for removing salt. N- (2,3-dihydroxypropyl) phthalimide obtained by hydrolyzing the epoxy group of the product was by-produced to reduce the yield and the purity of the product. Further, when an alcohol solvent is used, the solubility of the product is high. Therefore, in order to obtain the target product, it is necessary to concentrate it completely, which is not an efficient method.

Journal of the American Chemical Society, vol. 117, p. 11220-11229 (1995) Journal of Fluorine Chemistry Vol. 92, No. 2, p. 157-165 (1998) Synlett, p. 873-874 (1996) Helvetica Kimika Acta 73, p. 912-915 (1990) Journal of Chemical Research 2004 APRIL, 276-278

JP 7-89922 A JP 60-42375 A JP 2004-292425 A

  Accordingly, an object of the present invention is to solve the above-described problems of the prior art, and to provide a method for producing N-glycidylphthalimide having high industrial productivity, high yield and high purity. .

In view of the current state of the prior art, the present inventors have intensively studied to solve the above problems. As a result, in the method for producing N-glycidylphthalimide, epichlorohydrin is added to the phthalimide alkali salt.
(1) In the presence of 4 to 50 moles of epichlorohydrin with respect to the phthalimide alkali salt,
(2) in the presence of a quaternary ammonium salt and / or a phosphonium salt, and (3) a reaction temperature of 40 to 100 ° C.
It has been found that N-glycidylphthalimide can be obtained in high yield and high purity by reacting under the above conditions.

That is, in the present invention, when N-glycidylphthalimide is produced by reacting phthalimide alkali salt with epichlorohydrin,
(1) In the presence of 4 to 50 moles of epichlorohydrin with respect to the phthalimide alkali salt,
(2) in the presence of a quaternary ammonium salt and / or a quaternary phosphonium salt, and (3) a reaction temperature of 40 to 100 ° C.
It is a manufacturing method of N-glycidyl phthalimide characterized by making it react on these conditions.

  According to the preferable aspect of the manufacturing method of N-glycidyl phthalimide of this invention, it is making it react in the said reaction in the solvent which is aprotic and has a dipole moment of 2.0 D or less.

  According to a preferred aspect of the method for producing N-glycidylphthalimide of the present invention, the aprotic solvent having a dipole moment of 2.0 D or less is a hydrocarbon having 6 to 10 carbon atoms.

  According to a preferred embodiment of the method for producing N-glycidylphthalimide of the present invention, in the above reaction, the water content in the reaction system is 0.2% by weight or less.

  Moreover, the method for producing N-glycidylphthalimide of the present invention comprises the step of isolating N-glycidylphthalimide from a reaction solution in which epichlorohydrin is reacted with phthalimide alkali salt to form N-glycidylphthalimide. An alkali compound is added to the liquid. A method for producing N-glycidylphthalimide is provided.

  According to a preferred embodiment of the method for producing N-glycidylphthalimide of the present invention, the alkali compound is an alkali metal alkoxide.

  According to a preferred embodiment of the method for producing N-glycidylphthalimide of the present invention, after the reaction, unreacted epichlorohydrin remaining in the reaction solution is recovered and used again.

  According to the present invention, N-glycidylphthalimide is industrially high in productivity, and can be produced in high yield and high purity.

  For example, if impurities such as N- (3-chloro-2-hydroxypropyl) phthalimide are mixed in the product, the electrical and mechanical properties of the cured product using this will deteriorate due to the influence of chlorine contained in the product. End up. Moreover, durability and reliability will be low. That is, by purifying N-glycidylphthalimide, a cured product having high electrical characteristics and mechanical characteristics, and high durability and reliability can be obtained. Specifically, it is preferably used for a sealing material for electric / electronic parts, an insulating material, an adhesive, a composite material with glass fiber, carbon fiber, or the like.

  Below, it describes in detail about the manufacturing method of N-glycidyl phthalimide of this invention.

  The method for producing N-glycidylphthalimide of the present invention uses a phthalimide alkali salt as a starting substrate. Examples of phthalimide alkali salts include sodium phthalimide, phthalimide potassium, and phthalimide cesium, but potassium phthalimide that is inexpensive and industrially usable is particularly preferably used.

  In the method for producing N-glycidylphthalimide of the present invention, epichlorohydrin is reacted with a phthalimide alkali salt.

The amount of epichlorohydrin used is 4 to 50 mol times, preferably 4 to 30 mol times, particularly preferably 5 to 15 mol times with respect to the phthalimide alkali salt.
When the amount of epichlorohydrin used is less than 4 moles, the N-glycidylphthalimide produced by the reaction further reacts with the raw material phthalimide alkali salt to produce the dimer 2,2 ′-(2- Hydroxypropane-1,3-diyl) bis (2H-isoindole-1,3-dione) is by-produced remarkably. The by-product of 2,2 ′-(2-hydroxypropane-1,3-diyl) bis (2H-isoindole-1,3-dione) greatly reduces the yield of N-glycidylphthalimide. Moreover, it is not easy to separate this by-product from the target product, and the purification operation is complicated in order to obtain high-purity N-glycidylphthalimide. Moreover, when the usage-amount of epichlorohydrin exceeds 50 mol times, a substrate concentration will become low and productivity will worsen.

  In the reaction of the method for producing N-glycidylphthalimide of the present invention, a quaternary ammonium salt and / or a quaternary phosphonium salt is allowed to coexist. By adding and coexisting these salts, the reaction is accelerated and the productivity of N-glycidylphthalimide is improved.

The quaternary ammonium salts used in the present invention include tetramethylammonium, trimethyl-ethylammonium, dimethyldiethylammonium, triethyl-methylammonium, tripropyl-methylammonium, tributyl-methylammonium, trioctyl-methylammonium, tetraethylammonium, Trimethyl-propylammonium, trimethylphenylammonium, benzyltrimethylammonium, benzyltriethylammonium, diallyldimethylammonium, n-octyltrimethylammonium, stearyltrimethylammonium, cetyldimethylethylammonium, tetrapropylammonium, tetra-n-butylammonium, β-methylcholine Tetra-n-butylammonium Bromide salts such as finely phenyl trimethyl ammonium, chloride salt, iodine Casio, may be mentioned hydrogen sulfate and hydroxide, and the like.
Particularly preferred are trioctyl-methylammonium, tetraethylammonium, benzyltrimethylammonium, benzyltriethylammonium, tetra-n-butylammonium bromide, chloride, hydrogensulfate and hydroxide.

  The quaternary phosphonium salt used in the present invention includes tetramethylphosphonium, trimethyl-ethylphosphonium, dimethyldiethylphosphonium, triethyl-methylphosphonium, tripropyl-methylphosphonium, tributyl-methylphosphonium, trioctyl-methylphosphonium, tetraethyl. Phosphonium, trimethyl-propylphosphonium, trimethylphenylphosphonium, benzyltrimethylphosphonium, diallyldimethylphosphonium, n-octyltrimethylphosphonium, stearyltrimethylphosphonium, cetyldimethylethylphosphonium, tetrapropylphosphonium, tetran-butylphosphonium, tetra-n-butylphosphonium And bromide salts such as phenyltrimethylphosphonium Chloride salt, iodine Casio, may be mentioned hydrogen sulfate and hydroxide, and the like.

  The addition amount of the quaternary ammonium salt and / or quaternary phosphonium salt may be a catalytic amount, and is preferably 0.005 to 0.5 mole times the phthalimide alkali salt.

  Reaction in the manufacturing method of N-glycidyl phthalimide of this invention is implemented at reaction temperature 40-100 degreeC, Preferably it implements at 50-80 degreeC. If the reaction temperature is less than 40 ° C., the reaction rate is slow and a long reaction time is required. Moreover, when reaction temperature exceeds 100 degreeC, a side reaction will advance and will cause a yield fall.

  The reaction in the method for producing N-glycidylphthalimide of the present invention may be carried out without solvent or in the presence of a solvent.

  Since N-glycidyl phthalimide has low solubility in epichlorohydrin, when the reaction is carried out without a solvent, the produced N-glycidyl phthalimide precipitates during the reaction, making stirring difficult. Moreover, the raw material phthalimide alkali salt and by-products are taken into the precipitated N-glycidyl phthalimide crystal, making it difficult to obtain a high-purity one. By using a solvent, the product N-glycidylphthalimide is dissolved in the reaction system and homogenized, whereby the reaction can be completed easily. Furthermore, the reaction operation is facilitated, and in addition, recovery of unreacted epichlorohydrin is facilitated.

  When a solvent is used in the present invention, an aprotic solvent having a dipole moment of 2.0 D or less is preferably used. Specific examples of solvents that are aprotic and have a dipole moment of 2.0 D or less include hydrocarbon solvents such as hexane, 2-methylpentane, 2,2-dimethylbutane, 2,3-dimethylbutane, Examples include heptane, octane, isooctane, nonane, trimethylhexane, decane, dodecane, benzene, toluene, xylene, ethylbenzene, cumene, mesitylene, cyclohexylbenzene, diethylbenzene, cyclopentane, methylcyclopentane, cyclohexane, methylcyclohexane and ethylcyclohexane. .

  Examples of the ether solvent include diisopropyl ether, dibutyl ether, dihexyl ether, anisole, phenetole, diphenyl ether, tetrahydrofuran, tetrahydropyran, ethylene glycol dibutyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, and diethylene glycol dibutyl ether.

  Examples of the ester solvent include methyl acetate, ethyl acetate, propyl acetate, isopropyl acetate, butyl acetate, and isobutyl acetate.

  Among them, the solvent preferably used is a hydrocarbon solvent having 6 to 10 carbon atoms such as cyclohexane, toluene, xylene, ethylbenzene, cumene, mesitylene, and diethylbenzene.

  An aprotic solvent is a solvent that has no ability to give protons to the solvent itself and does not self-dissociate. Polarized molecules also have a dipole moment, the magnitude of which is represented by the magnitude of the direction vector from negative charge to positive charge, which is largely related to the dissolving power.

  When a polar solvent having a protonic property or a dipole moment of greater than 2.0D is used, the crystallization yield may be lowered due to the high solubility of the target N-glycidylphthalimide. In order to raise this, it will concentrate and dry like background art, and is unsuitable for industrial operation. In general, these solvents often contain water that induces side reactions, which is not preferable from the viewpoint of reaction yield.

  In the present invention, the amount of the solvent used is preferably 0.1 to 20 times the weight of the phthalimide potassium salt, depending on the solubility of the phthalimide potassium salt and the product, the slurry concentration, or the properties of the reaction solution.

  In the reaction of the method for producing N-glycidylphthalimide of the present invention, the water content in the reaction system is preferably 0.2% by weight or less. If the water content in the reaction system is large, a large amount of N- (2,3-dihydroxypropyl) phthalimide obtained by hydrolysis of the epoxy group of N-glycidylphthalimide is produced as a by-product, and the yield tends to be reduced.

  It is preferable to use a phthalimide alkali salt, epichlorohydrin, quaternary ammonium salt and / or quaternary phosphonium salt and solvent, which are raw materials for the reaction, which have been dehydrated and / or dried in advance to reduce the water content.

  In the present invention, in the step of isolating N-glycidylphthalimide from a reaction solution in which epichlorohydrin is reacted with phthalimide alkali salt to form N-glycidylphthalimide, an alkali compound is added to the reaction solution.

  In the present invention, in the above isolation step, after unreacted epichlorohydrin and a part of the solvent are distilled off, the oil layer is washed with water in order to remove sodium chloride produced by the reaction from the oil layer. Subsequently, the target N-glycidylphthalimide is isolated from the oil layer from which sodium chloride has been removed by a concentrated crystallization method or a poor solvent crystallization method. In this step, by adding an alkali compound to the oil layer, N- (3-chloro-2-hydroxypropyl) phthalimide or N- (2,3-dihydroxypropyl) phthalimide, which is a decomposition product of N-glycidylphthalimide, is added. Life is suppressed.

  Examples of the alkali compound used in the present invention include lithium hydroxide, sodium hydroxide, potassium hydroxide, barium hydroxide, magnesium hydroxide, calcium hydroxide, lithium carbonate, sodium carbonate, potassium carbonate, barium carbonate, magnesium carbonate, Calcium carbonate, lithium hydrogen carbonate, sodium hydrogen carbonate, potassium hydrogen carbonate, lithium hydride, sodium hydride, potassium hydride, sodium methoxide, potassium methoxide, sodium ethoxide, potassium ethoxide, sodium n-propoxide, potassium n-propoxide, sodium isopropoxide, potassium isopropoxide, sodium n-butoxide, potassium n-butoxide, sodium tert-butoxide, potassium tert-butoxide, sodium tert Examples include amylate, potassium tert-amylate, sodium n-hexylate, and potassium n-hexylate and tetramethylammonium hydroxide. Among them, alkali metal alkoxides such as sodium methoxide, potassium methoxide, sodium ethoxide, potassium Ethoxide, sodium n-propoxide, potassium n-propoxide, sodium isopropoxide, potassium isopropoxide, sodium n-butoxide, potassium n-butoxide, sodium tert-butoxide and potassium tert-butoxide are preferably used.

  The addition amount of the alkali compound used in the present invention is preferably 0.0005 to 1.0 mol times, more preferably 0.01 to 0.5 mol times with respect to N-glycidylphthalimide. The alkali compound may be added as it is, but may be dropped as water or an alcohol solution.

  In the present invention, the epichlorohydrin and / or the solvent distilled off from the reaction solution in the isolation step can be recovered and reused. From the viewpoint of reducing the basic unit and waste, it can be recovered. Epichlorohydrin and / or a solvent that has been prepared can be preferably used.

  The high-purity N-glycidyl phthalimide thus obtained is preferably used as a composite material with a sealing material for electric / electronic parts, an insulating material or an adhesive, glass fiber, carbon fiber, or the like.

  Hereinafter, although the Example demonstrates the manufacturing method of N-glycidyl phthalimide concretely, this invention is not restrict | limited only to an Example.

Example 1
In a four-necked flask equipped with a thermometer, dropping funnel, condenser and stirrer, 277.6 g (3.0 mol) of epichlorohydrin (water content 0.02% by weight), 5.1 g of tetrabutylammonium hydrogen sulfate ( 0.015 mol) was added, the temperature was raised to 60 ° C. while purging with nitrogen, and 92.6 g (0.5 mol) of potassium phthalimide (water content: 0.2 wt%) was added thereto over 2 hours. The water content of the reaction solution after the addition was 0.06% by weight. Furthermore, when this reaction liquid was stirred at a temperature of 60 ° C. for 3 hours, N-glycidylphthalimide was produced at a reaction yield of 84.7%. The results are shown in Table 1.

(Comparative Example 1)
A four-necked flask equipped with a thermometer, dropping funnel, condenser and stirrer was charged with 277.6 g (3.0 mol) of epichlorohydrin (water content 0.02 wt%), and the temperature was adjusted while purging with nitrogen. The temperature was raised to 60 ° C., and 92.6 g (0.5 mol) of potassium phthalimide (water content: 0.2% by weight) was added thereto over 2 hours. The water content of the reaction solution after the addition was 0.07% by weight. Furthermore, although this reaction liquid was stirred at a temperature of 60 ° C. for 12 hours, N-glycidylphthalimide was not obtained. The results are shown in Table 1.

(Comparative Example 2)
In Example 1, it implemented like Example 1 except having used 73.6 g (0.5 mol) of phthalimide (water content 0.02 weight%) instead of phthalimide potassium. The water content of the reaction solution after the addition was 0.05% by weight. N-glycidyl phthalimide was produced with a reaction yield of 47.7%. The results are shown in Table 1.

(Example 2)
In a four-necked flask equipped with a thermometer, dropping funnel, condenser and stirrer, 277.6 g (3.0 mol) of epichlorohydrin (water content 0.02% by weight), 138.9 g of toluene, tetrabutyl hydrogen sulfate Ammonium 5.1 g (0.015 mol) was charged, the temperature was raised to 60 ° C. while purging with nitrogen, and 92.6 g (0.5 mol) of potassium phthalimide (water content 0.2 wt%) was added to this over 2 hours. Added. The water content of the reaction solution after the addition was 0.05% by weight. Further, this reaction solution was stirred at a temperature of 60 ° C. for 3 hours, and N-glycidylphthalimide was produced at a reaction yield of 84.0%. The results are shown in Table 1.

(Example 3)
In Example 1, it implemented like Example 1 except having used 138.9g of xylene instead of toluene. The water content of the reaction solution after the addition was 0.05% by weight. N-glycidyl phthalimide was produced with a reaction yield of 84.0%. The results are shown in Table 1.

Example 4
In Example 3, it implemented like Example 3 except having performed the reaction temperature after adding phthalimide potassium and the reaction temperature at 80 degreeC. The water content of the reaction solution after the addition was 0.05% by weight. N-glycidyl phthalimide was produced with a reaction yield of 82.1%. The results are shown in Table 1.

(Example 5)
In a four-necked flask equipped with a thermometer, dropping funnel, condenser and stirrer, 277.6 g (3.0 mol) of epichlorohydrin (water content 0.02 wt%), 138.9 g of xylene, tetrabutyl hydrogen sulfate Ammonium 5.1 g (0.015 mol) was charged and the temperature was raised to 60 ° C. while purging with nitrogen, and 92.6 g (0.5 mol) of potassium phthalimide (water content 0.2 wt%) was added to this over 2 hours. Added. The water content of the reaction solution after the addition was 0.05% by weight. Further, this reaction solution was stirred at a temperature of 60 ° C. for 3 hours, and N-glycidylphthalimide was produced at a reaction yield of 84.0%. A part of epichlorohydrin and xylene was distilled off from this reaction solution, and 324.1 g of a mixed solvent of epichlorohydrin and xylene (epichlorohydrin: xylene = 65: 35 (weight ratio), water content 0. 03 wt%) was recovered.

  Into a four-necked flask equipped with a thermometer, dropping funnel, condenser and stirrer, this recovered liquid and epichlorohydrin (water content 0.02 wt%) 66.9 g, xylene 25.5 g, and tetrabutyl hydrogen sulfate Ammonium 5.1 g (0.015 mol) was charged and the temperature was raised to 60 ° C. while purging with nitrogen, and 92.6 g (0.5 mol) of potassium phthalimide (water content 0.2 wt%) was added to this over 2 hours. Added. The water content of the reaction solution after the addition was 0.06% by weight. Further, this reaction solution was stirred at a temperature of 60 ° C. for 3 hours, and N-glycidylphthalimide was produced at a reaction yield of 83.1%. The results are shown in Table 1.

(Reference Example 1)
In a four-necked flask equipped with a thermometer, dropping funnel, condenser and stirrer, 277.6 g (3.0 mol) of epichlorohydrin (water content 0.02 wt%), 138.9 g of xylene, tetrabutyl hydrogen sulfate Ammonium 5.1 g (0.015 mol) was charged, the temperature was raised to 60 ° C. while purging with nitrogen, and 92.6 g (0.5 mol) of potassium phthalimide (water content 1.6 wt%) was added to this over 2 hours. Added. The water content of the reaction solution after the addition was 0.3% by weight. Further, this reaction solution was stirred at a temperature of 60 ° C. for 3 hours, and N-glycidylphthalimide was produced at a reaction yield of 79.8%. The results are shown in Table 1.

(Reference Example 2)
In a four-necked flask equipped with a thermometer, dropping funnel, condenser and stirrer, 277.6 g (3.0 mol) of epichlorohydrin (water content 0.02 wt%), 138.9 g of xylene, tetrahydrogen sulfate Butylammonium 5.1 g (0.015 mol) and water 4.9 g were charged, and the temperature was raised to 60 ° C. while purging with nitrogen. 5 mol) was added over 2 hours. The water content of the reaction solution after the addition was 1.0% by weight. Further, this reaction solution was stirred at a temperature of 60 ° C. for 3 hours, and N-glycidylphthalimide was produced at a reaction yield of 19.5%. The results are shown in Table 1.

(Example 6)
A part of epichlorohydrin was distilled off from the reaction solution obtained in Example 1 to obtain 282.7 g of a concentrated solution. 231.5 g of xylene was added thereto, and 7.7 g (0.04 mol) of a 28 wt% sodium methylate methanol solution was added and stirred at a temperature of 60 ° C. for 30 minutes, and then the water 185 was kept at a temperature of 60 ° C. Washed twice with 2 g. Thereafter, the oil layer was concentrated again to obtain 147.4 g of a concentrated liquid. Crystallization was performed by adding 70.4 g of xylene thereto. Crystallization was performed by adding 0.1 g of seed crystals at a temperature of 55 ° C., and when the reaction solution started to become cloudy, the temperature was decreased by 10 ° C. per hour and stirred at a temperature of 15 ° C. for 1 hour. Solid-liquid separation was performed. As a result, 72.6 g (purity (LC area%) 90.3%, pure conversion yield 64.5%) of white powder N-glycidylphthalimide was obtained. The results are shown in Table 2.

(Example 7)
A portion of epichlorohydrin and toluene was distilled off from the reaction solution obtained in Example 2 to obtain 282.7 g of a concentrated solution. 92.6 g of toluene was added thereto, and further 7.7 g (0.04 mol) of 28 wt% sodium methylate methanol solution was added and stirred at a temperature of 60 ° C. for 30 minutes, and then kept at a temperature of 60 ° C. with water. Washed twice with 185.2 g. Thereafter, the oil layer was concentrated again to obtain 147.4 g of a concentrated liquid. To this was added 70.4 g of toluene for crystallization. The crystallization operation was performed by adding 0.1 g of seed crystals at a temperature of 55 ° C., and stirring the reaction solution. Solid-liquid separation was performed. As a result, 61.7 g of N-glycidylphthalimide (purity (LC area%) 90.0%, yield in terms of pure content 54.7%) was obtained. The results are shown in Table 2.

(Example 8)
From the reaction solution obtained in Example 3, after completion of the reaction, epichlorohydrin and a part of xylene were distilled off to obtain 282.7 g of a concentrated solution. 92.6 g of xylene was added thereto, and 7.7 g (0.04 mol) of 28 wt% sodium methylate methanol solution was added and stirred at a temperature of 60 ° C. for 30 minutes, and then kept at 60 ° C. with water. Washed twice with 185.2 g. Thereafter, the oil layer was concentrated again to obtain 147.4 g of a concentrated liquid. Crystallization was performed by adding 70.4 g of xylene thereto. The crystallization operation was performed by adding 0.1 g of seed crystals at a temperature of 55 ° C., and stirring the reaction solution. Solid-liquid separation was performed. As a result, 67.4 g of N-glycidylphthalimide (purity (LC area%) 90.0%, pure conversion yield 59.7%) was obtained. The results are shown in Table 2.

Example 9
From the reaction liquid obtained in Example 5, after completion of the reaction, epichlorohydrin and a part of xylene were distilled off to obtain 282.7 g of a concentrated liquid. 92.6 g of xylene was added thereto, and further 7.7 g (0.04 mol) of 28 wt% sodium methylate methanol solution was added at a temperature of 60 ° C. and stirred for 30 minutes, and then the temperature was kept at 60 ° C. It was washed twice with 185.2 g of water. Next, crystallization was performed from the obtained separated oil layer. In the crystallization operation, 0.1 g of seed crystals was added at a temperature of 45 ° C. When the reaction solution started to become cloudy, the temperature was decreased by 10 ° C. per hour, stirred at 15 ° C. for 1 hour, and then solid-liquid separation was performed. went. As a result, 76.1 g (purity (LC area%) 89.2%, pure conversion yield 66.8%) of white powder N-glycidylphthalimide was obtained. The results are shown in Table 2.

(Comparative Example 3)
In Example 8, except that the 28 wt% sodium methylate methanol solution was not added, the same operation as in Example 8 was performed. As a result, 67.4 g of N-glycidylphthalimide (purity (LC area%) 81.8) was obtained. %, Yield in terms of pure content of 54.3%). The results are shown in Table 2.

Claims (7)

In producing N-glycidylphthalimide by reacting phthalimide alkali salt with epichlorohydrin,
(1) In the presence of 4 to 50 moles of epichlorohydrin with respect to the phthalimide alkali salt,
(2) in the presence of a quaternary ammonium salt and / or a quaternary phosphonium salt, and (3) a reaction temperature of 40 to 100 ° C.
The manufacturing method of N-glycidyl phthalimide characterized by making it react on condition of this.   The method for producing N-glycidylphthalimide according to claim 1, wherein the reaction is carried out in a solvent that is aprotic and has a dipole moment of 2.0 D or less.   The method for producing N-glycidylphthalimide according to claim 2, wherein the solvent that is aprotic and has a dipole moment of 2.0 D or less is a hydrocarbon having 6 to 10 carbon atoms.   The method for producing N-glycidylphthalimide according to any one of claims 1 to 3, wherein the water content in the reaction system is 0.2 wt% or less.   In the step of isolating N-glycidylphthalimide from a reaction solution in which epichlorohydrin is reacted with phthalimide alkali salt to form N-glycidylphthalimide, an alkali compound is added to the reaction solution. A method for producing glycidylphthalimide.   The method for producing N-glycidylphthalimide according to claim 5, wherein the alkali compound is an alkali metal alkoxide.   The method for producing N-glycidylphthalimide according to any one of claims 1 to 6, wherein after the reaction, unreacted epichlorohydrin remaining in the reaction solution is recovered and used again.