JPH0892192A - Production of cyanate compound - Google Patents

Abstract

PURPOSE: To easily obtain a cyanate compound in high safety, purity and yield by simultaneously adding a t-amine and a cyanogen halide to a specific bisphenol compound, reacting the compounds with each other, washing the product and separating the liquid phases. CONSTITUTION: The objective cyanate compound is produced by adding (A) a t-amine such as triethylamine and (B) a cyanogen halide such as cyanogen chloride at the same time to (C) a bisphenol compound of formula I (A is H or a 1-6C alkyl; X is single bond, a 1-20C organic group, carbonyl, sulfone, S or O; (i) is 0-4) in the presence of a solvent forming separable phases with water such as methyl isobutyl ketone, subjecting the reaction product to the washing with water and the separation into liquid phases to remove the t-amine hydrohalogenic acid salt, contacting the obtained solution (concentrate) with a poor solvent selected from sec-alcohols, t-alcohols and hydrocarbons to cause the crystallization or precipitation and obtain purified product. The compound is useful as a sealing resin for electronic parts or a resin for laminated board, composite material, molded article or adhesive.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a cyanate compound which is useful for encapsulating electronic parts, laminating plates, composite materials, molding materials and adhesives.

[0002]

2. Description of the Related Art Heretofore, as a method for producing a cyanate compound, there has been known a method (U.S. Pat. No. 3,553,244) in which a corresponding hydroxy compound is reacted with cyanogen halide and a base such that the cyanogen halide is always in excess of the base. Has been. In this method, a method in which a hydrohalide salt of a tertiary amine that is exclusively produced is removed by filtration, and then the resulting solution is concentrated or precipitated in water to take out a product is carried out. The inventors of the present invention have revealed that these methods result in a low yield and cannot completely remove the dialkylcyanamide and the halogen ion by-produced from the tertiary amine and the cyanogen halide.

[0003]

SUMMARY OF THE INVENTION In view of the above problems, an object of the present invention is to provide a process which is highly safe, simple in process, and capable of obtaining a high-purity cyanate compound in a high yield. It is in.

[0004]

Means for Solving the Problems The inventors of the present invention have conducted extensive studies on a method for producing a cyanate compound, and as a result, use a reaction solvent capable of separating water and water, and carry out water washing separation after completion of the reaction. High purity by removing the hydrogen halide salt of primary amine and crystallization or precipitation of the crude product with a poor solvent arbitrarily selected from secondary alcohols, tertiary alcohols, and hydrocarbons It was found that the cyanate of 1 was obtained and the present invention was completed.

That is, the present invention is represented by the following general formula (I)

[Chemical 4] (In the formula, A is independently a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, X is a single bond, and 1 to 20 carbon atoms.
The organic group, carbonyl group, sulfone group, divalent sulfur atom or oxygen atom, i represents an integer of 0 or more and 4 or less. )
A tertiary amine and a cyanogen halide were simultaneously added to the bisphenol compound represented by the formula (1) in the presence of water and a solvent capable of liquid separation, and then the liquid was washed with water to separate the hydrogen halide salt of the tertiary amine to obtain a product. The solution or the crude product obtained by concentrating the solution as necessary is brought into contact with a poor solvent arbitrarily selected from secondary alcohols, tertiary alcohols and hydrocarbons for crystallization or precipitation. The present invention relates to a method for producing a cyanate compound, which comprises refining and purifying.

Any bisphenol compound can be used as long as it satisfies the general formula (I). For example, 4,4'-dihydroxydiphenyl and 3,3 ', 5,5'-tetramethyl can be used. -4,4'-
Dihydroxydiphenyl, bis (hydroxyphenyl)
Methane, bis (4-hydroxy-3,5-dimethylphenyl) methane, bis (2-hydroxy-3-t-butyl-5-methylphenyl) methane, bis (4-hydroxyphenyl) ethane, 2,2-bis (4-hydroxyphenyl) propane (formula

[0007]

[Chemical 5] It is represented by. ), 2,2-bis (3,5-dimethyl-4)
-Hydroxyphenyl) propane, 2,2-bis (3-
Methyl-4-hydroxyphenyl) propane, 2,2-
Bis (4-hydroxy-3-t-butylphenyl) propane, 2,2-bis (4-hydroxy-3-t-butyl-6-methylphenyl) propane, 2,2-bis (3-
Allyl-4-hydroxyphenyl) propane, 1,1-
Bis (4-hydroxy-3-t-butyl-6-methylphenyl) butane (formula

[0008]

[Chemical 6] It is represented by. ), 1,1-bis (4-hydroxyphenyl) cyclohexane, 1,1-bis (4-hydroxy-)
3-Methylphenyl) cyclohexane, 1,1-bis (4-hydroxy-3-cyclohexyl-6-methyl)
Butane, bis (4-hydroxyphenyl) menthane, bis (4-hydroxy-3,5-dimethyl) menthane, bis (4-hydroxy-3-t-butyl-6-methylphenyl) mentane, bis (4-hydroxyphenyl) ) Tricyclo [5,2,1,0 ^2,6 ] decane, bis (4-hydroxy-3,5-dimethylphenyl) tricyclo [5,5
2,1,0 ^2,6 ] decane, bis (4-hydroxy-3-
t-butyl-6-methylphenyl) tricyclo [5,5
2,1,0 ^2,6 ] decane, bis (4-hydroxyphenyl) sulfide, bis (4-hydroxy-3,5-dimethylphenyl) sulfide, bis (4-hydroxy-3)
Examples include -t-butyl-6-methylphenyl) sulfide, bis (4-hydroxyphenyl) sulfone, bis (4-hydroxyphenyl) carbonyl, bis (4-hydroxyphenyl) ether and the like. Particularly, bis (4-hydroxyphenyl) propane is industrially readily available and preferred. In addition, 1,1-bis (4-hydroxy-3-t-
Butyl-6-methylphenyl) butane is preferred because the polymer (polytriazine) obtained from the cyanate compound produced therefrom has a significantly low dielectric constant.

The tertiary amine used is trimethylamine, triethylamine, tripropylamine, dimethylethylamine, tributylamine, dimethylaniline,
Examples thereof include diethylaniline, pyridine, quinoline and the like.

The reaction solvent capable of separating from water is a ketone solvent such as methyl ethyl ketone or methyl isobutyl ketone, an aromatic solvent such as benzene, toluene or xylene,
Ether solvents such as diethyl ether, tetrahydrofuran, etc., halogenated hydrocarbons such as methylene chloride, chloroform, carbon tetrachloride, chlorobenzene, nitrile solvents such as benzonitrile, nitro solvents such as nitrobenzene, ethyl acetate, ethyl benzoate, etc. The ester-based solvent can be used. Of these, a ketone solvent is preferred, and methyl isobutyl ketone is most preferred.

The reaction is carried out by simultaneously adding the tertiary amine and cyanogen halide to the bisphenol compound in the presence of a reaction solvent capable of separating from water. Specifically, for example, the bisphenol compound is first dissolved in a solvent, and a predetermined amount of a tertiary amine and a cyanogen halide are added thereto, followed by dropwise injection together with the cyanogen halide in advance. As the cyanogen halide, cyanogen chloride or cyanogen bromide is used. When cyanogen chloride is used, the reaction temperature is −30 to 15 ° C., more preferably −10.
C to 15C, -30C to 65 when using cyanogen bromide
It is carried out at temperatures up to ° C. The tertiary amine is 1.0 to 5 times equivalent, preferably 1.0 to 1.5 times equivalent to the hydroxyl group of the hydroxy compound, and the cyanogen halide is 3 to 5 times equivalent.
Instead of adding an equivalent amount of a primary amine or excess cyanogen halide, acidity may be adjusted by adding a mineral acid such as hydrochloric acid or sulfuric acid.

The after-treatment is carried out by washing with water to remove the by-produced tertiary amine hydrogen halide salt, and then the resulting solution or a crude product obtained by concentrating the solution is used as a secondary product. It is carried out by bringing into contact with a poor solvent arbitrarily selected from alcohols, tertiary alcohols and hydrocarbons, and crystallizing or precipitating it for purification. In order to wash the tertiary amine efficiently, the reaction solution can be washed with an acidic aqueous solution such as hydrochloric acid. Concentration is preferably carried out under reduced pressure at a temperature of 120 ° C. or lower, and if the temperature is raised too high, cyanate trimerization will start, which is not preferable. Crystallization or precipitation is carried out by adding the product to the poor solvent or vice versa. As the poor solvent, secondary or tertiary alcohol solvents such as isopropyl alcohol, amyl alcohol and t-butyl alcohol, and hydrocarbons such as benzene, toluene, xylene, hexane and petroleum ether are preferable. The alcohols may be mixed with water at an arbitrary ratio and used. Moreover, you may mix and use the said several solvent in arbitrary ratios. Primary alcohols such as methanol and ethanol can be used, but they are not preferable because the yield is reduced.

[0013]

EXAMPLES Examples of the present invention will be shown below, but the present invention is not limited thereto. Example 1 2,2-bis (4-hydroxyphenyl) propane (manufactured by Mitsui Toatsu Chemicals, Inc.) 11 in a reactor equipped with a thermometer, a stirrer, a dropping funnel and a reflux condenser under a nitrogen atmosphere.
4.2 g (0.5 mol), methyl isobutyl ketone 6
After charging 85 g and dissolving at room temperature, the solution was cooled to 0 ° C. Next, 67.7 g (1.1 mol) of cyanogen chloride was added dropwise over 2 hours. 5 minutes after the start of dropwise addition of cyanogen chloride, 111.2 g (1.1 mol) of triethylamine was added to 0 to 6
The mixture was added dropwise at 2 ° C. for 2 hours and 30 minutes and kept at the same temperature for 30 minutes. After washing with 300 g of 3% hydrochloric acid water, water 300
It was washed twice with g and separated. The reaction yield was 99% from the dicyanate content in the obtained organic layer. Next, the organic layer was concentrated under reduced pressure to 178 g, 228 g of isopropyl alcohol was added dropwise, and the mixture was cooled to 5 ° C. and stirred for 3 hours. The obtained slurry was filtered, washed with 114 g of isopropyl alcohol, and then air-dried to obtain 121.1 g of white crystals having a melting point of 80 ° C. (yield 87%). The raw materials bisphenol and monocyanate were not detected by LC (liquid chromatography). The obtained white crystals are G
When analyzed by C (gas chromatography), diethyl cyanamide was not detected. An attempt was made to analyze chloride ion by potentiometric titration using silver nitrate, but the content of chloride ion was 10 ppm or less.

Example 2 141.5 g (1.4 m) of triethylamine was used in Example 1.
ol) and 86.1 g (1.4 mol) of cyanogen chloride were used under the same conditions, except that white crystals were 115.3 g.
Was obtained (yield 83%). The raw materials bisphenol and monocyanate were not detected by LC. The obtained white crystals were analyzed by GC, but no diethylcyanamide was detected. In addition, we tried to analyze chloride ion by potentiometric titration method using silver nitrate.
It was 0 ppm or less.

Example 3 The procedure of Example 1 was repeated except that 73.8 g (1.2 mol) of cyanogen chloride was used, to obtain 118 g of white crystals (yield 85%). The raw materials bisphenol and monocyanate were not detected by LC. The obtained white crystals were analyzed by GC, but no diethylcyanamide was detected. In addition, an attempt was made to analyze chloride ion by potentiometric titration using silver nitrate.
It was below ppm.

Example 4 The same procedure as in Example 1 was repeated except that heptane was used as the solvent for crystallization and washing, to obtain 110.5 g of white crystals (yield 80%). The raw materials bisphenol and monocyanate were not detected by LC. The obtained white crystals were analyzed by GC, but no diethylcyanamide was detected. In addition, we tried to analyze chloride ion by potentiometric titration using silver nitrate.
It was m or less.

Example 5 155.7 g of white crystals was obtained (yield 89%) under the same conditions as in Example 1 except that the crystallization and washing solvent used was an aqueous 86% isopropyl alcohol solution. The raw materials bisphenol and monocyanate were not detected by LC. The obtained white crystals were analyzed by GC, but no diethylcyanamide was detected. An attempt was made to analyze chloride ion by potentiometric titration using silver nitrate, but the content of chloride ion was 10 ppm or less.

Example 6 In a reactor equipped with a thermometer, a stirrer, a dropping funnel and a reflux condenser, under a nitrogen atmosphere, 1,1-bis (4-hydroxy-).
3-Methylphenyl) cyclohexane 500.0 g
(1.68 mol), methyl isobutyl ketone 2400
g was charged, dissolved at room temperature and cooled to 0 ° C. Next, 227.4 g (3.70 mol) of cyanogen chloride was added dropwise over 2 hours. 5 minutes after the start of dropwise addition of cyanogen chloride, 374 g (3.70 mol) of triethylamine was added at 0 to 6 ° C. for 2 minutes.
The mixture was added dropwise over 30 minutes and kept at the same temperature for 30 minutes. Wash with 500 g of 3% hydrochloric acid aqueous solution, then 500 g
It was washed twice with water and separated. The reaction yield was 99% from the dicyanate content in the obtained organic layer. Then, the organic layer was concentrated under reduced pressure to concentrate the solvent to about 900 g, and then 1000 g of isopropyl alcohol was added dropwise, and the temperature was adjusted to 5 ° C.
And cooled to stir for 3 hours. The obtained slurry was filtered, washed with 500 g of isopropyl alcohol, and dried under reduced pressure to obtain 495.7 g of white crystals having a melting point of 94 ° C. (yield 85
%). The raw materials bisphenol and monocyanate were not detected by LC. The obtained white crystals are G
When analyzed by C, no diethyl cyanamide was detected. An attempt was made to analyze chloride ion by potentiometric titration using silver nitrate, but the content of chloride ion was 10 ppm or less.

Example 7 In a reactor equipped with a thermometer, a stirrer, a dropping funnel and a reflux condenser, under a nitrogen atmosphere, 1,1-bis (4-hydroxy-).
3-t-butyl-6-methylphenyl) butane (Sumitomo Chemical Co., Ltd., trade name Sumilizer BBM-S) 20
0.0 g (0.53 mol) and 800 g of methyl isobutyl ketone were charged, dissolved at room temperature and cooled to 0 ° C. Next, 96.4 g (1.57 mol) of cyanogen chloride was added dropwise over 2 hours. Five minutes after the start of dropwise addition of cyanogen chloride, 148.1 g (1.46 mol) of triethylamine was added to 0 to
The mixture was added dropwise at 6 ° C. over 2 hours and 30 minutes and kept at the same temperature for 30 minutes. It was washed with 300 g of a 3% aqueous hydrochloric acid solution, and further washed twice with 300 g of water and separated. The reaction yield was 92% from the content of the dicyanate compound in the obtained organic layer. Next, the organic layer was concentrated under reduced pressure to concentrate the solvent to about 450 g, 400 g of isopropyl alcohol was added dropwise, and the mixture was cooled to 5 ° C. and stirred for 3 hours. The obtained slurry was filtered, washed with 200 g of isopropyl alcohol, and dried under reduced pressure to give 203.9 g of white crystals having a melting point of 122 to 123 ° C.
Was obtained (yield 90%). The purity of the dicyanate body by LC was 92.3%. The obtained white crystals were analyzed by GC, but no diethylcyanamide was detected. An attempt was made to analyze chloride ion by potentiometric titration using silver nitrate, but the content of chloride ion was 10 ppm or less.

Comparative Example 1 2,2-bis (4-hydroxyphenyl) propane (manufactured by Mitsui Toatsu Chemicals, Inc.) in a reactor equipped with a thermometer, a stirrer, a dropping funnel and a reflux condenser under a nitrogen atmosphere. ) 400
g (1.76 mol), acetone 933 g and cyanogen chloride 258.9 g (4.21 mol) were charged, dissolved at room temperature and cooled to 0 ° C. Next, triethylamine 3
72.8 g (3.68 mol) was added dropwise at 0 to 6 ° C over 1 hour, and the temperature was kept at the same temperature for 1 hour. Next, the obtained reaction solvent was dissolved in 5,000 ml of water and crystallized to obtain yellowish white crystals. The crystals were washed with 2000 ml of water and then dried under reduced pressure to obtain 245.1 g of yellowish white crystals having a melting point of 76 to 78 ° C. (yield 61%). The obtained yellowish white crystal was analyzed by GC to find that diethylcyanamide was 2.1%.
Detected. In addition, an attempt was made to analyze chlorine ions by a potentiometric titration method using silver nitrate, and the obtained yellowish white crystals contained 830 ppm of chlorine ions.

Comparative Example 2 91.3 g of white crystals were obtained (yield 66%) under the same conditions as Example 1 except that methanol was used as the crystallization and washing solvent. The purity of the dicyanate body by LC is 9
It was 9.5%. The obtained white crystals were analyzed by GC, but no diethylcyanamide was detected. An attempt was made to analyze chloride ion by potentiometric titration using silver nitrate, but the content of chloride ion was 10 ppm or less.

[0022]

As is apparent from the examples, by controlling the dropping method of cyanogen halide and tertiary amine and removing the by-product salt by water separation, secondary or tertiary alcohols,
By crystallization or precipitation with a poor solvent arbitrarily selected from hydrocarbons, a high-purity dicyanate product could be obtained in high yield. As shown in the comparative example, when the tertiary amine was added dropwise to the mixed solvent of the cyanogen halide and the hydroxy compound and the product was taken out by water precipitation, the yield of the desired dicyanate compound was low, and the tertiary amine and the cyanogen halide were obtained. It was revealed that the dialkylcyanamide and halogen ions produced as a by-product cannot be completely removed. Further, when a primary alcohol is used as a poor solvent, it is difficult to obtain a dicyanate body in high yield. It can be said that the present invention is an excellent process which is safe without causing a large amount of highly dangerous cyanogen halide to stay in the reaction tank and can be carried out on an industrial scale.

Claims (5)

[Claims] 1. The following general formula (I): (In the formula, A is independently a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, X is a single bond, and 1 to 20 carbon atoms.
The organic group, carbonyl group, sulfone group, divalent sulfur atom or oxygen atom, i represents an integer of 0 or more and 4 or less. )
A tertiary amine and a cyanogen halide were simultaneously added to the bisphenol compound represented by the formula (1) in the presence of water and a solvent capable of liquid separation, and then the liquid was washed with water to separate the hydrogen halide salt of the tertiary amine to obtain a product. Solution or a crude product obtained by concentrating the solution if necessary, is brought into contact with a poor solvent arbitrarily selected from secondary alcohols, tertiary alcohols and hydrocarbons for crystallization or precipitation. A method for producing a cyanate compound, which comprises: 2. The method for producing a cyanate compound according to claim 1, wherein the bisphenol compound represented by the general formula [I] is represented by the following formula. [Chemical 2] 3. The method for producing a cyanate compound according to claim 2, wherein methyl isobutyl ketone is used as a reaction solvent, and isopropyl alcohol or hydrous isopropyl alcohol is used for crystallization or precipitation for purification. 4. The method for producing a cyanate compound according to claim 1, wherein the bisphenol compound represented by the general formula [I] is represented by the following formula. [Chemical 3] 5. The method for producing a cyanate compound according to claim 4, wherein methyl isobutyl ketone is used as a reaction solvent, and isopropyl alcohol or hydrous isopropyl alcohol is used for crystallization or precipitation for purification.