JP3674877B2 - Crystal transformation of alkylamine salt of bis (4-hydroxyphenyl) acetic acid and process for producing the same - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a crystal transformation of a chemical product and a method for producing the same. More particularly, the present invention relates to a crystal modification of an alkylamine salt of bis (4-hydroxyphenyl) acetic acid and a production method thereof.
[0002]
[Prior art]
The alkylamine salt of bis (4-hydroxyphenyl) acetic acid is an important compound as a developer and color reducing agent for a reversible thermosensitive recording material.
Although it is known that a carboxylic acid and an amine form a salt, there is no detailed literature on a specific method for producing an alkylamine salt of bis (4-hydroxyphenyl) acetic acid. In the examples of JP-A-6-171224, a method for producing salts thereof from bis (4-hydroxyphenyl) acetic acid, stearylamine and laurylamine is simply described, but the reaction temperature and purification method are mentioned. It is not done. In addition, this method has a problem that crystals are colored during drying or solidified in a granular form. When such a crystal is used, the dispersibility may be deteriorated or the color may be colored when preparing a heat-sensitive coating liquid.
[0003]
[Problems to be solved by the invention]
In order to produce the alkylamine salt of bis (4-hydroxyphenyl) acetic acid industrially at low cost, it is necessary to increase the concentration as much as possible. However, the above method has a low concentration and a long reaction time. It is difficult to say that it is an efficient method. Therefore, establishment of a method for efficiently obtaining an alkylamine salt of bis (4-hydroxyphenyl) acetic acid as white crystals is desired.
[0004]
[Means for Solving the Problems]
As a result of intensive studies on a method for efficiently producing an alkylamine salt of bis (4-hydroxyphenyl) acetic acid at low cost, the present inventors have made preparations by heating reaction in an organic solvent depending on the type of alkylamine. The concentration can be increased, the reaction time can be shortened, the yield can be increased, and the obtained crystals have good filterability, and the purity is improved by washing with a specific organic solvent and water. Thus, the present invention was completed.
[0005]
That is, the present invention
(1) Diffraction angles (2θ) [°] 4.0 to 5.0, 12.2 to 13.3, 16.3 to 17.8, 17.9 to 18 in the X-ray diffraction method using Cu—Kα rays Crystal modification of the alkylamine salt of bis (4-hydroxyphenyl) acetic acid characterized by an X-ray diffraction pattern showing a peak at .7 (2) The number of carbon atoms of the alkylamine is 8-18, Crystal modification of alkylamine salt of bis (4-hydroxyphenyl) acetic acid (3) An organic solvent solution of bis (4-hydroxyphenyl) acetic acid and a heated melt of alkylamine or an organic solvent solution of alkylamine at 30 to 120 ° C. The present invention relates to a method for producing an alkylamine salt of bis (4-hydroxyphenyl) acetic acid as described in (1) and (2) above, wherein the mixture is heated and mixed.
[0006]
In JP-A-6-171224, a salt is formed when an organic solvent solution of an organic acid and an organic solvent solution of an amine compound are mixed, but there is no description about the temperature during the reaction. Usually, the reaction is performed at room temperature, but the inventors have found that the alkylamine is dissolved by heating or dissolved in an organic solvent by heating, and an organic solvent solution of bis (4-hydroxyphenyl) acetic acid. It cannot be easily analogized that a salt having a good crystal form can be obtained by heating and mixing at 30 to 120 ° C. In this method, since the hot melt of alkylamine can be used as it is, it is possible to save the trouble of dissolving the alkylamine in the solvent, and it becomes more efficient.
Further, after the reaction as described in JP-A-6-171224, when the cake is heated and dried as it is, it may be colored during drying or solidified in a granular form. When solidified, not only is the recovery of crystals complicated, but the dispersibility may deteriorate when preparing a heat-sensitive coating solution, affecting the quality itself. The present inventors have found out that this problem can be prevented by washing the cake after the reaction with a solvent and then with water, thereby preventing coloring during drying and granulation of crystals. In general, organic acid salts are considered to be easily soluble in water, but alkylamine salts of bis (4-hydroxyphenyl) acetic acid have low solubility in water, and washing with water does not significantly affect the yield. . Moreover, since the solvent is replaced with water by drying after washing with water, the solvent odor at the time of drying can be prevented, and the safety and working environment are improved.
[0007]
Hereinafter, the present invention will be described in detail.
In carrying out the production method of the present invention, the reaction solvent used is used in such an amount that the resulting salt is usually 0.1 to 1.5 mol / l, preferably 0.3 to 0.8 mol / l. If the amount of salt produced is too much relative to the solvent, stirring becomes difficult and the removal becomes complicated. If the amount is too small, the yield is lowered and it is not economical. As the solvent to be used, a solvent having low solubility of the generated salt and good solubility of bis (4-hydroxyphenyl) acetic acid or alkylamine may be selected. As a specific example of such a solvent, methanol is used. , Alcohols such as ethanol, propanol and butanol, glycols such as ethylene glycol and diethylene glycol, esters such as methyl acetate and ethyl acetate, acetone, methyl ethyl ketone and methyl isobutyl ketone Ketones, benzene, toluene, xylene and the like.
[0008]
The alkylamine used in the present invention may be either a linear or branched alkylamine, but a preferred alkylamine is an alkylamine having 8 to 18 carbon atoms, and specific examples of the alkylamine that can be used. As octylamine, nonylamine, decylamine, undecylamine, laurylamine, tridecylamine, tetradecylamine, pentadecylamine, cetylamine, heptadecylamine, stearylamine, etc., among these laurylamine, cetylamine, stearyl Amines are particularly preferred. These may be used alone or in combination of two or more. These alkylamines can be used either after being melted by heating or after being dissolved in an organic solvent.
[0009]
The amount of bis (4-hydroxyphenyl) acetic acid used relative to the alkylamine is usually 1.3 to 0.7 times (molar ratio), preferably 1.1 to 0.9 times, and particularly preferably 1.05 to 0.95. Is double.
[0010]
In this invention, reaction temperature is 30 to 120 degreeC, Preferably it is 40 to 80 degreeC. If the temperature is too low, bis (4-hydroxyphenyl) acetic acid and alkylamine must be charged at a low concentration, which is not efficient.
[0011]
The reaction time is not particularly limited, but is usually 1 minute to 20 hours, preferably 10 minutes to 5 hours, and particularly preferably 30 minutes to 3 hours.
[0012]
The solvent for washing the crystals after the reaction may be selected so long as it does not dissolve the generated salt and dissolves unreacted bis (4-hydroxyphenyl) acetic acid or alkylamine. It is not necessary to use the solvent used for the reaction. Absent. In this case, it is preferable to select a solvent that can be easily replaced with water. Specific examples of the washing solvent that can be used include those used as the reaction solvent. When the crystals after washing with the solvent are dried as they are, they may be colored or solidified into particles, which is considered to be caused by the remaining solvent. Therefore, after washing with a solvent, it is washed with tap water, ion exchange water, distilled water or the like and then dried. Thereby, a solvent is substituted by water and the solvent odor during drying can be prevented. The drying temperature is preferably 20 ° C to 60 ° C. If the drying temperature is too high, there is a tendency to color during drying. The crystals obtained by the production method of the present invention have diffraction angles (2θ) [°] 4.0 to 5.0, 12.2 to 13.3, 16.3 to 17.3 in the X-ray diffraction method using Cu—Kα rays. This is a crystal modification characterized by an X-ray diffraction pattern having peaks at 8, 17.9 to 18.7, and is a white fine needle crystal.
[0013]
【Example】
EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to only these examples.
[0014]
Reference example 1
60 ml of a solution in which laurylamine is dissolved in acetone to a concentration of 0.8 mol / l is placed in 300 ml of Kolben, and while stirring at 30 ° C., bis (4-hydroxyphenyl) acetic acid is dissolved in acetone at 0.8 mol / l. 60 ml of the solution dissolved so as to have a concentration of 1 was added dropwise little by little. Stirring was continued as it was, and crystals formed after 1 hour from the end of dropping were filtered at room temperature. The cake was washed with 100 ml of acetone and then with 150 ml of ion exchange water. This was dried at 50 ° C. for 2 days to obtain a laurylamine salt of bis (4-hydroxyphenyl) acetic acid. The yield was 86.9%. This crystal is a white fine needle-like crystal and has diffraction angles (2θ) [°] of 4.93, 12.35, 14.85, 17.69, 18.02 in the X-ray diffraction method using Cu—Kα rays. Showed a peak. See FIG.
[0015]
Comparative Example 1
100 ml of a solution in which laurylamine is dissolved in acetone to a concentration of 0.3 mol / l is placed in 300 ml of Kolben, and bis (4-hydroxyphenyl) acetic acid is added to acetone in an amount of 0.1% while stirring at room temperature (20 ° C.). 100 ml of a solution dissolved so as to have a concentration of 3 mol / l was dropped in small portions. Stirring was continued as it was, and crystals formed after 1 hour from the end of dropping were filtered at room temperature. The cake was dried at 50 ° C. for 2 days to obtain laurylamine salt of bis (4-hydroxyphenyl) acetic acid. Yield is 83.2. %Met. This crystal was a yellow crystal, and it was hard to take out due to solidification.
[0016]
Example 1
120 ml of a solution in which amine PB (trade name, cetylamine, manufactured by NOF Corporation) was dissolved in methyl ethyl ketone at a concentration of 0.8 mol / l at 55 ° C. was placed in 300 ml Kolben, and stirred at 55 ° C. 120 ml of a solution obtained by dissolving bis (4-hydroxyphenyl) acetic acid in methyl ethyl ketone at a concentration of 0.8 mol / l was added dropwise over 20 minutes. Stirring was continued as it was, and the crystal formed 1 hour after the completion of the dropwise addition was gradually cooled to 20 ° C. and filtered. The cake was washed at 150C with 150 ml methyl ethyl ketone and then with 250 ml tap water. This was dried at 40 ° C. for 2 days to obtain a cetylamine salt of bis (4-hydroxyphenyl) acetic acid. The yield was 87.2%. This crystal is a white fine needle-like crystal and shows strong peaks at diffraction angles (2θ) [°] 4.48, 13.09, 17.43, 18.57 in the X-ray diffraction method using Cu—Kα rays. It was. See FIG.
[0017]
Example 2
120 ml of a solution prepared by dissolving amine PB in 1-butanol at a concentration of 0.8 mol / l at 40 ° C. was placed in 300 ml Kolben, and while stirring at 40 ° C., bis (4-hydroxyphenyl) acetic acid was 120 ml of a solution dissolved in butanol at a concentration of 0.8 mol / l was dropped in portions over 30 minutes. Stirring was continued while gradually cooling, and the crystals formed after 1 hour from the end of dropping were water-cooled to 20 ° C. and filtered. The cake was washed at 150C with 150 ml 1-butanol and then with 250 ml distilled water. This was dried at 60 ° C. for 2 days to obtain a cetylamine salt of bis (4-hydroxyphenyl) acetic acid. The yield was 88.7%. This crystal is a white fine needle-like crystal and shows strong peaks at diffraction angles (2θ) [°] 4.30, 12.91, 17.26, 18.39 in the X-ray diffraction method using Cu—Kα rays. It was. See FIG.
[0018]
Comparative Example 2
120 ml of a solution prepared by dissolving amine PB in 1-butanol at a concentration of 0.8 mol / l at room temperature was placed in 300 ml of Kolben, and while stirring at room temperature (20 ° C.), bis (4-hydroxyphenyl) acetic acid was added. 120 ml of a solution dissolved in 1-butanol at a concentration of 0.8 mol / l was added dropwise over 30 minutes. Stirring was continued as it was, and the crystals formed one hour after the completion of dropping were cooled with water to 20 ° C. and filtered. Even if the cake was dried at 60 ° C. for 2 days, it did not reach a constant weight. Three days after drying, a cetylamine salt of bis (4-hydroxyphenyl) acetic acid was obtained. The yield was 91.8%. This crystal was a brown crystal, and it was hard to take out because it was solidified. Moreover, the solvent odor was strong during drying, and the working environment was deteriorated.
[0019]
Example 3
300 ml of a solution in which amine PB was dissolved in 1-butanol at a concentration of 1.0 mol / l at 40 ° C. was placed in 1 l Kolben, and bis (4-hydroxyphenyl) acetic acid was added at 40 ° C. while stirring at 40 ° C. Then, 300 ml of a solution dissolved in 1-butanol at a concentration of 1.0 mol / l was added dropwise over 1 hour. Stirring was continued while gradually cooling, and after 2 hours from the end of dropping, the mixture was cooled to 20 ° C. with water, and the produced crystals were filtered. The cake was washed at 20 ° C. with 500 ml of 1-butanol and then with 1 l of distilled water. This was dried at 50 ° C. for 2 days to obtain a cetylamine salt of bis (4-hydroxyphenyl) acetic acid. The yield was 86.4%. This crystal was a white fine needle-like crystal and showed strong peaks at diffraction angles (2θ) [°] 4.35, 12.96, 17.30, 18.44 in the X-ray diffraction method using Cu—Kα rays. . See FIG.
[0020]
Example 4
0.05 mol of cetylamine was placed in 300 ml of Kolben and completely melted at 60 ° C. To this, 100 ml of a 1-butanol solution in which 0.05 mol of bis (4-hydroxyphenyl) acetic acid was dissolved was kept at 60 ° C. with stirring and added dropwise little by little over 40 minutes. Stirring was continued while gradually cooling, and after 1 hour from the end of dropping, the mixture was cooled to 20 ° C. with water, and the produced crystals were filtered. The cake was washed at 20 ° C. with 80 ml of 1-butanol and then with 250 ml of tap water. This was dried at 50 ° C. for 18 hours to obtain a cetylamine salt of bis (4-hydroxyphenyl) acetic acid. The yield was 89.3%. This crystal was a white fine needle-like crystal and showed strong peaks at diffraction angles (2θ) [°] 4.30, 12.93, 17.28, 18.39 in the X-ray diffraction method using Cu-Kα rays. . See FIG.
[0021]
Example 5
0.05 mol of cetylamine was placed in 300 ml of Kolben and completely melted at 60 ° C. To this, 100 ml of an ethanol solution in which 0.05 mol of bis (4-hydroxyphenyl) acetic acid was dissolved was kept at 60 ° C. with stirring and added dropwise little by little over 40 minutes. Stirring was continued while gradually cooling, and after 1 hour from the end of dropping, the mixture was cooled to 20 ° C. with water, and the produced crystals were filtered. The cake was washed with 20 ml of ethanol at 80 ° C. and then washed with 150 ml of tap water and 80 ml of distilled water in this order. This was dried at 50 ° C. for 18 hours to obtain a cetylamine salt of bis (4-hydroxyphenyl) acetic acid. The yield was 91.9%. This crystal was a white fine needle-like crystal and showed strong peaks at diffraction angles (2θ) [°] 4.22, 12.83, 17.18, 18.30 in the X-ray diffraction method using Cu—Kα rays. . See FIG.
[0022]
Example 6
120 ml of a solution in which a mixture of alkylamines containing amine ABT (trade name, cetylamine 30%, stearylamine 66%, manufactured by NOF Corporation) is dissolved in butanol at 40 ° C. to a concentration of 0.8 mol / l Into 300 ml of Kolben, 120 ml of a solution in which bis (4-hydroxyphenyl) acetic acid was dissolved in butanol at a concentration of 0.8 mol / l at 40 ° C. was added dropwise over 15 minutes while stirring at 40 ° C. Stirring was continued as it was, and after 1 hour from the end of dropping, the mixture was cooled with water to lower the temperature to 25 ° C., and the produced crystals were filtered. This was dried under reduced pressure at 25 ° C. for 2 days to obtain an alkylamine salt of bis (4-hydroxyphenyl) acetic acid. The yield was 86.9%. This crystal was a white fine needle-like crystal and showed strong peaks at diffraction angles (2θ) [°] 4.12, 12.36, 16.50, 18.34 in the X-ray diffraction method using Cu—Kα rays. . See FIG.
[0023]
【The invention's effect】
By heating and reacting a mixed solution in which bis (4-hydroxyphenyl) acetic acid and alkylamine are dissolved, the concentration of preparation can be increased, and the yield is increased and the efficiency is improved. Further, by washing the crystals after the reaction with a solvent and water, coloring and granulation during drying can be prevented.
[Brief description of the drawings]
1 is an X-ray diffraction pattern of a laurylamine salt of bis (4-hydroxyphenyl) acetic acid obtained in Reference Example 1. FIG. (In FIG. 1, the vertical axis represents the diffraction intensity, and the horizontal axis represents the diffraction angle (2θ) [°].)
2 is an X-ray diffraction pattern of a cetylamine salt of bis (4-hydroxyphenyl) acetic acid obtained in Example 1. FIG. (In FIG. 2, the vertical axis represents the diffraction intensity, and the horizontal axis represents the diffraction angle (2θ) [°].)
3 is an X-ray diffraction pattern of a cetylamine salt of bis (4-hydroxyphenyl) acetic acid obtained in Example 2. FIG. (In FIG. 3, the vertical axis represents the diffraction intensity, and the horizontal axis represents the diffraction angle (2θ) [°].)
4 is an X-ray diffraction pattern of a cetylamine salt of bis (4-hydroxyphenyl) acetic acid obtained in Example 3. FIG. (In FIG. 4, the vertical axis represents the diffraction intensity, and the horizontal axis represents the diffraction angle (2θ) [°].)
5 is an X-ray diffraction pattern of a cetylamine salt of bis (4-hydroxyphenyl) acetic acid obtained in Example 4. FIG. (In FIG. 5, the vertical axis represents the diffraction intensity, and the horizontal axis represents the diffraction angle (2θ) [°].)
6 is an X-ray diffraction pattern of a cetylamine salt of bis (4-hydroxyphenyl) acetic acid obtained in Example 5. FIG. (In FIG. 6, the vertical axis represents the diffraction intensity, and the horizontal axis represents the diffraction angle (2θ) [°].)
7 is an X-ray diffraction pattern of an alkylamine salt of bis (4-hydroxyphenyl) acetic acid obtained in Example 6. FIG. (In FIG. 7, the vertical axis represents the diffraction intensity, and the horizontal axis represents the diffraction angle (2θ) [°].)

Claims (2)

In an X-ray diffraction method using Cu-Kα rays obtained by heating and mixing an organic solvent solution of bis (4-hydroxyphenyl) acetic acid and a heated melt of alkylamine or an organic solvent of alkylamine at 40 to 80 ° C. Characterized by X-ray diffraction patterns showing peaks at folding angles (2θ) [°] 4.12 to 4.48, 12.3 to 13.09, 16.50 to 17.43, 18.30 to 18.57. A method for producing an alkylamine salt of bis (4-hydroxyphenyl) acid. The method for producing an alkylamine salt of bis (4-hydroxyphenyl) acetic acid according to claim 1, wherein the alkylamine has 8 to 18 carbon atoms.

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