JP2011236189A - Method for synthesizing disubstituted isocyanuric acid compound - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a disubstituted isocyanuric acid compound useful as a synthetic raw material of a new resin additive, such as diallyl isocyanurate, dimethallyl isocyanurate, allyl methallyl isocyanurate, etc.SOLUTION: This method for synthesizing the disubstituted isocyanuric acid compounds expressed by general formula is provided by repeating the partial hydrolysis of using an alkali hydroxide and alkylation of using an alkyl halide of trialkyl cyanurates in an aprotic polar organic solvent alternately. All of these compounds can be synthesized in a good purity by using inexpensive raw materials such as cyanuric chloride, sodium hydroxide, an alcohol and ally halides.

Description

  Diallyl isocyanurate (hereinafter abbreviated as DAIC), dimethallyl isocyanurate (hereinafter abbreviated as DMAIC), allylmeta represented by the general formula of Chemical Formula 1 useful as a raw material for synthetic rubber raw materials and synthetic resin additives such as electrical insulating resins The present invention relates to a method for synthesizing disubstituted isocyanuric acid compounds such as allyl isocyanurate (hereinafter abbreviated as AMAIC).

  Cyanuric acid ester or isocyanuric acid ester, especially triallyl isocyanurate (hereinafter abbreviated as TAIC) and triallyl cyanurate (hereinafter abbreviated as TAC) are useful as monomer raw materials, crosslinking agents, modifiers and the like for various synthetic resins. A polymer synthesized from a raw material containing a compound is excellent in wear resistance and heat resistance.

  However, a polymer synthesized from a raw material containing these in a high ratio has a drawback that it is brittle and has low flexibility. In order to compensate for this, development of diallyl cyanurate derivatives and diallyl isocyanurate derivatives has been promoted (Patent Document 1), and an efficient synthesis method of diallyl cyanurate (Patent Document 2) and DAIC has been desired. It was.

  To date, the patent literature for DAIC synthesis includes (1) reaction of isocyanuric acid with allyl halide (Patent Document 3), or (2) heating triallyl cyanurate in xylene in the presence of phenol and activated clay. (Patent Document 4) has been reported. In addition, non-patent literature reports a method of synthesis by reaction with allyl isocyanate and cyanate (Non-patent literature 1).

  However, in all conventional synthesis methods, the yield of DAIC is low, and a large amount of monoallyl isocyanurate is produced as a by-product. Therefore, it is necessary to repeat recrystallization to extract pure DAIC, resulting in high production costs. Therefore, there was a limit to practical use. In addition, it has been impossible to synthesize an asymmetric disubstituted isocyanuric acid compound such as AMAIC by the conventional method.

  JP 2007-238472 A   Japanese Patent No. 4329325   JP-A-4-49285   US Patent No. 2830051

  Journal of Organic Chemistry, Vo. 35, NO. 7, 2253-7, 1970

  The present invention has been made to solve the above-mentioned difficulties associated with the synthesis of a disubstituted isocyanuric acid compound and to provide a method for synthesizing a versatile and multifunctional disubstituted isocyanuric acid compound at a low cost.

  Any of these is a method of synthesizing a disubstituted isocyanuric acid compound represented by the general formula 1 using cyanuric chloride, sodium hydroxide, alcohol and allyl halides which are inexpensive raw materials as raw materials.

That is, as shown in the general formula shown in Chemical Formula 2, first, a trialkyl cyanurate intermediate (2) was synthesized using cyanuric chloride (1) and an inexpensive alcohol (shown by ROH), and this was combined with sodium hydroxide. (8) is generated by alternately repeating partial hydrolysis using allylic acid and allylation using allyl halides (4) or (7) twice, and finally only one remaining oxygen-alkyl bond Is a method of synthesizing a disubstituted isocyanuric acid compound (9) by hydrolyzing the compound with an acid or an alkali.

  According to the present invention, it has become possible to synthesize a disubstituted isocyanurate compound, which has been conventionally expected as a raw material for functional resin monomers, crosslinking agents, and modifiers, at low cost and with high purity. Further, by using the technology relating to the present invention, not only DAIC and DMAIC but also asymmetric compounds such as AMAIC can be synthesized. This makes it possible to introduce three different substituents on the triazine ring, which can lead to new compounds with higher performance than conventional isocyanuric esters, and the effects are enormous. .

Form of invention

  Hereafter, the principle regarding the synthesis | combination of the disubstituted isocyanuric acid compound in this invention is demonstrated in detail (refer chemical formula 2).

  First, trialkyl cyanurate (2) is synthesized by reacting cyanuric chloride (1) with sodium hydroxide in an alcohol solvent.

  When this triallyl cyanurate (2) is contacted with sodium hydroxide in an aprotic polar organic solvent such as DMSO, only one of the three oxygen-alkyl bonds is hydrolyzed and the resulting dialkyl salt of cyanuric acid (3) is generated. When allyl halides (4) are allowed to act on (3), the nitrogen atom in the triazine ring is alkylated to produce intermediate (5).

  In addition, ester groups consisting of oxygen-alkyl bonds such as triallyl cyanurate are easily hydrolyzed with sodium hydroxide, but nitrogen-alkyl bonds are not hydrolyzed with sodium hydroxide. As a result, one of the two remaining oxygen-alkyl bonds of intermediate (5) is hydrolyzed to produce intermediate (6), which is again alkylated using allyl halides (7). This produces intermediate (8).

  Then, the disubstituted isocyanuric acid compound (9) can be obtained by cleaving the remaining oxygen-alkyl bond in the intermediate (8) under acidic or alkaline conditions.

  In any of the trialkyl cyanurates used in the examples, the hydrolysis is completely completed by heating at 60 ° C. for 1 hour using a 50% aqueous sodium hydroxide solution (Example 1-5). When the sodium hydroxide was used, it was difficult to dissolve in DMSO, so the temperature had to be raised to 80 ° C. (Examples 6-8).

  In addition, as the allyl halide used in the present invention, allyl bromide is preferably used from the viewpoint of the yield of the target product DAIC, and the reactivity is low when a cheaper allyl chloride is used. Even if the reaction time was lengthened, the yield decreased (Comparative Examples 3 and 5). However, when using allyl chloride, (1) using pelleted sodium hydroxide during alkali hydrolysis, (2) increasing the reaction temperature during hydrolysis and allylation, (3) equivalent of allyl chloride The yield could be improved by increasing the number (Example 6).

  Further, the final hydrolysis had no effect on the yield whether it was performed under acidic conditions or alkaline conditions (compare Example 3 and Example 4).

  As a notable feature regarding this technology, the synthesis of the disubstituted isocyanuric acid compound shown above has undergone a plurality of step reactions, and in this example, the intermediate (2) is once taken out and the reaction vessel is replaced. Industrially, a series of reactions from cyanuric chloride (1) to compound (9) can be carried out continuously in one synthesis reaction kettle.

  In addition, according to this method, since only a small amount of monoallyl cyanurate is produced as a by-product, pure DAIC can be produced by performing the liquid separation operation and the crystallization only once. By finding this method, it has become possible to produce DAIC, DMAIC, and AMAIC, which are polymer materials having excellent thermal stability and high-frequency electrical characteristics, at low cost.

  Hereinafter, the present invention will be described with reference to examples, and the results obtained by the present invention are summarized in Table 1.

  Pelletized sodium hydroxide (12.5 g, 300 mmol) and methanol (100 ml) were charged into a 500 ml four-necked flask. While the reaction system was cooled in an ice bath and stirred, 18.4 g (100 mmol) of cyanuric chloride was added over 30 minutes. The ice bath was removed and stirred for 1.5 hours at room temperature. Methanol was removed from the reaction solution by distillation under reduced pressure. Separation operation was performed by adding 400 ml of toluene and 100 ml of water to the concentrate. Concentration of the organic layer yielded 14.9 g (87 mmol) of trimethylcyanurate (crude yield 87%).

To the trimethyl cyanurate obtained above, 30 ml of DMSO and 7.2 g (90 mmol) of 50% aqueous sodium hydroxide solution were added and stirred at 60 ° C. for 1 hour. 10.8 g (90 mmol) of allyl bromide was added and stirred at 60 ° C. for 1 hour. A 50% aqueous sodium hydroxide solution (7.2 g, 90 mmol) was added, and the mixture was stirred at 60 ° C. for 1 hour. 10.8 g (90 mmol) of allyl bromide was added and stirred at 60 ° C. for 1 hour. It was stirred for 2 hours at _{H 2 SO 4 2.94g (30mmol)} / H 2 O20ml addition 60 ° C.. DAIC produced by acid hydrolysis was precipitated. After adding 4.0 g (96 mmol) of sodium hydroxide and 330 ml of water to dissolve all the crystals, liquid separation was performed using 50 ml of toluene, and impurities were extracted into the toluene layer. With stirring to the aqueous layer _{H 2 SO 4 4.9g (50mmol)} / H 2 O20ml adding the DAIC solid precipitated. The solid obtained by filtration was washed with 50 ml of water and then dried at 60 ° C. until a constant weight was obtained. 4.60 g of almost pure DAIC crystals were obtained (total yield 22%).

  12.5 g (300 mmol) of pelleted sodium hydroxide and 100 ml of 2-propanol were charged into a 500 ml four-necked flask, and 18.4 g (100 mmol) of cyanuric chloride was added over 30 minutes with stirring. The ice bath was removed and the mixture was stirred for 2 hours at room temperature. 2-Propanol was removed from the reaction solution by distillation under reduced pressure. Separation operation was performed by adding 100 ml of toluene and 100 ml of water to the concentrate. Concentration of the organic layer yielded 14.0 g (55 mmol) of triisopropyl cyanurate (crude yield 55%).

To the triisopropyl cyanurate obtained above, 20 ml of DMSO and 4.4 g (55 mmol) of 50% aqueous sodium hydroxide solution were added and stirred at 60 ° C. for 1 hour. 6.7 g (55 mmol) of allyl bromide was added and stirred at 60 ° C. for 1 hour. 4.4 g (55 mmol) of 50% aqueous sodium hydroxide solution was added and stirred at 60 ° C. for 1 hour. 6.7 g (55 mmol) of allyl bromide was added and stirred at 60 ° C. for 1 hour. H ₂ SO ₄ (2.0 g, 20 mmol) / H ₂ O (20 ml) was added, and the mixture was stirred at 60 ° C. for 2 hours. DAIC produced by acid hydrolysis was precipitated. After adding 3.34 g (84 mmol) of sodium hydroxide and 220 ml of water to dissolve all the crystals, liquid separation was performed using 40 ml of toluene, and impurities were extracted into the toluene layer. With stirring to the aqueous layer _{H 2 SO 4 4.2g (42mmol)} / H 2 O12ml adding the DAIC solid precipitated. The solid obtained by filtration was washed with 50 ml of water and then dried at 60 ° C. until a constant weight was obtained. 5.43 g of almost pure DAIC crystals were obtained (total yield 26%).

  Pelletized sodium hydroxide (12.5 g, 300 mmol) and ethanol (100 ml) were charged into a 500 ml four-necked flask. While the reaction system was cooled in an ice bath and stirred, 18.4 g (100 mmol) of cyanuric chloride was added over 30 minutes. The ice bath was removed and stirred for 1.5 hours at room temperature. The salt was removed from the reaction solution by filtration under reduced pressure. When ethanol was removed from the filtrate by vacuum distillation, 19.7 g (92 mmol) of triethyl cyanurate was obtained (crude yield 92%).

To the triethyl cyanurate obtained above, 30 ml of DMSO and 7.6 g (95 mmol) of 50% aqueous sodium hydroxide solution were added and stirred at 60 ° C. for 1 hour. 11.5 g (95 mmol) of allyl bromide was added and stirred at 60 ° C. for 1 hour. 7.6 g (95 mmol) of 50% aqueous sodium hydroxide solution was added and stirred at 60 ° C. for 1 hour. 11.5 g (95 mmol) of allyl bromide was added and stirred at 60 ° C. for 1 hour. It was stirred for 2 hours at _{H 2 SO 4 2.94g (30mmol)} / H 2 O20ml addition 60 ° C.. DAIC produced by acid hydrolysis was precipitated. After adding 4.0 g (96 mmol) of sodium hydroxide and 330 ml of water to dissolve all the crystals, liquid separation was performed using 50 ml of toluene, and impurities were extracted into the toluene layer. With stirring to the aqueous layer _{H 2 SO 4 4.9g (50mmol)} / H 2 O20ml adding the DAIC solid precipitated. The solid obtained by filtration was washed with 50 ml of water and then dried at 60 ° C. until a constant weight was obtained. 11.6 g of nearly pure DAIC crystals were obtained (total yield 55%).

  Pelletized sodium hydroxide (12.5 g, 300 mmol) and ethanol (100 ml) were charged into a 500 ml four-necked flask. While the reaction system was cooled in an ice bath and stirred, 18.4 g (100 mmol) of cyanuric chloride was added over 30 minutes. The ice bath was removed and stirred for 1.5 hours at room temperature. The salt was removed from the reaction solution by filtration under reduced pressure. When ethanol was removed from the filtrate by distillation under reduced pressure, 19.7 g (92 mmol) of triethyl cyanurate was obtained (yield: about 92%).

To the triethyl cyanurate obtained above, 30 ml of DMSO and 7.6 g (95 mmol) of 50% aqueous sodium hydroxide solution were added and stirred at 60 ° C. for 1 hour. 11.5 g (95 mmol) of allyl bromide was added and stirred at 60 ° C. for 1 hour. 7.6 g (95 mmol) of 50% aqueous sodium hydroxide solution was added and stirred at 60 ° C. for 1 hour. 11.5 g (95 mmol) of allyl bromide was added and stirred at 60 ° C. for 1 hour. 7.3 g (92 mmol) of 50% aqueous sodium hydroxide solution was added and stirred at 60 ° C. for 2 hours. After 330 ml of water was added to dissolve all solids, liquid separation was performed using 50 ml of toluene, and impurities were extracted into the toluene layer. With stirring to the aqueous layer _{H 2 SO 4 4.9g (50mmol)} / H 2 O20ml adding the DAIC solid precipitated. The solid obtained by filtration was washed with 50 ml of water and then dried at 60 ° C. until a constant weight was obtained. 11.6 g of nearly pure DAIC crystals were obtained (total yield 55%).

  Pelletized sodium hydroxide (12.5 g, 300 mmol) and ethanol (100 ml) were charged into a 500 ml four-necked flask. While the reaction system was cooled in an ice bath and stirred, 18.4 g (100 mmol) of cyanuric chloride was added over 30 minutes. The ice bath was removed and stirred for 1.5 hours at room temperature. The salt was removed from the reaction solution by filtration under reduced pressure. When ethanol was removed from the filtrate by distillation under reduced pressure, 20.5 g (96 mmol) of triethyl cyanurate was obtained (crude yield 96%).

To the triethyl cyanurate obtained above, 30 ml of DMSO and 7.6 g (95 mmol) of 50% aqueous sodium hydroxide solution were added and stirred at 60 ° C. for 1 hour. 7.3 g (95 mmol) of allyl chloride was added and stirred at 60 ° C. for 1 hour. 7.6 g (95 mmol) of 50% aqueous sodium hydroxide solution was added and stirred at 60 ° C. for 1 hour. 7.3 g (95 mmol) of allyl chloride was added and stirred at 60 ° C. for 1 hour. It was stirred for 2 hours at _{H 2 SO 4 2.94g (30mmol)} / H 2 O20ml addition 60 ° C.. DAIC produced by acid hydrolysis was precipitated. After adding 4.0 g (96 mmol) of sodium hydroxide and 330 ml of water to dissolve all the crystals, liquid separation was performed using 50 ml of toluene, and impurities were extracted into the toluene layer. With stirring to the aqueous _layer, DAIC solid precipitated the addition of _{H 2 SO 4 4.9g (50mmol)} / H 2 O20ml. The solid obtained by filtration was washed with 50 ml of water and then dried at 60 ° C. until a constant weight was obtained. 6.00 g of almost pure DAIC crystals were obtained (total yield 29%).

  Pelletized sodium hydroxide (12.5 g, 300 mmol) and ethanol (100 ml) were charged into a 500 ml four-necked flask. While the reaction system was cooled in an ice bath and stirred, 18.4 g (100 mmol) of cyanuric chloride was added over 30 minutes. The ice bath was removed and stirred for 1.5 hours at room temperature. The salt was removed from the reaction solution by filtration under reduced pressure. When ethanol was removed from the filtrate by vacuum distillation, 20.6 g (97 mmol) of triethyl cyanurate was obtained (crude yield 97%).

To the triethyl cyanurate obtained above, 30 ml of DMSO and 4.0 g (96 mmol) of a sodium hydroxide aqueous solution in a pellet form were added and stirred at 80 ° C. for 1 hour. 9.2 g (120 mmol) of allyl chloride was added and stirred at 80 ° C. for 2 hours. 4.0 g (96 mmol) of pelleted sodium hydroxide was added and stirred at 60 ° C. for 1 hour. 9.2 g (120 mmol) of allyl chloride was added and stirred at 60 ° C. for 2 hours. 7.7 g (96 mmol) of 50% aqueous sodium hydroxide solution was added and stirred at 80 ° C. for 2 hours. After 330 ml of water was added to dissolve all the crystals, liquid separation was performed using 50 ml of toluene, and impurities were extracted into the toluene layer. With stirring to the aqueous layer _{H 2 SO 4 4.9g (50mmol)} / H 2 O20ml adding the DAIC solid precipitated. The solid obtained by filtration was washed with 50 ml of water and then dried at 60 ° C. until a constant weight was obtained. 8.4 g of nearly pure DAIC crystals were obtained (total yield 40%).

  Pelletized sodium hydroxide (12.5 g, 300 mmol) and ethanol (100 ml) were charged into a 500 ml four-necked flask. While the reaction system was cooled in an ice bath and stirred, 18.4 g (100 mmol) of cyanuric chloride was added over 30 minutes. The ice bath was removed and stirred for 1.5 hours at room temperature. The salt was removed from the reaction solution by filtration under reduced pressure. When ethanol was removed from the filtrate by vacuum distillation, 20.6 g (97 mmol) of triethyl cyanurate was obtained (crude yield 97%).

To the triethyl cyanurate obtained above, 30 ml of DMSO and 4.0 g (96 mmol) of a sodium hydroxide aqueous solution in a pellet form were added and stirred at 80 ° C. for 1 hour. 10.9 g (120 mmol) of methallyl chloride was added and stirred at 80 ° C. for 2 hours. 4.0 g (96 mmol) of pelleted sodium hydroxide was added and stirred at 80 ° C. for 1 hour. 10.9 g (120 mmol) of methallyl chloride was added and stirred at 80 ° C. for 2 hours. 7.7 g (96 mmol) of 50% aqueous sodium hydroxide solution was added and stirred at 80 ° C. for 2 hours. After 330 ml of water was added to dissolve all the crystals, liquid separation was performed using 50 ml of toluene, and impurities were extracted into the toluene layer. With stirring to the aqueous layer _{H 2 SO 4 4.9g (50mmol)} / H 2 O20ml adding the DMAIC solid precipitated. The solid obtained by filtration was washed with 50 ml of water and then dried at 60 ° C. until a constant weight was obtained. 2.36 g of almost pure DMAIC crystals were obtained (total yield: 10%).

  Pelletized sodium hydroxide (12.5 g, 300 mmol) and ethanol (100 ml) were charged into a 500 ml four-necked flask. While the reaction system was cooled in an ice bath and stirred, 18.4 g (100 mmol) of cyanuric chloride was added over 30 minutes. The ice bath was removed and stirred for 1.5 hours at room temperature. The salt was removed from the reaction solution by filtration under reduced pressure. When ethanol was removed from the filtrate by distillation under reduced pressure, 20.6 g (97 mmol) of triethyl cyanurate was obtained (yield: about 97%).

To the triethyl cyanurate obtained above, 30 ml of DMSO and 4.0 g (96 mmol) of a sodium hydroxide aqueous solution in a pellet form were added and stirred at 80 ° C. for 1 hour. 10.9 g (120 mmol) of methallyl chloride was added and stirred at 80 ° C. for 2 hours. 4.0 g (96 mmol) of pelleted sodium hydroxide was added and stirred at 80 ° C. for 1 hour. 10.9 g (120 mmol) of allyl chloride was added and stirred at 80 ° C. for 2 hours. 7.7 g (96 mmol) of 50% aqueous sodium hydroxide solution was added and stirred at 80 ° C. for 2 hours. After 330 ml of water was added to dissolve all the crystals, liquid separation was performed using 50 ml of toluene, and impurities were extracted into the toluene layer. With stirring to the aqueous layer _{H 2 SO 4 4.9g (50mmol)} / H 2 O20ml adding the AMAIC solid precipitated. The solid obtained by filtration was washed with 50 ml of water and then dried at 60 ° C. until a constant weight was obtained. 5.13 g of almost pure AMAIC crystals were obtained (23% overall yield).

Claims (5)

It is represented by the general formula of Chemical Formula 1, characterized by alternately repeating partial hydrolysis of trialkylcyanurates in an aprotic polar organic solvent using an alkali hydroxide and alkylation using an alkyl halide. Synthesis method of disubstituted isocyanuric acid compounds.

  The method for synthesizing disubstituted isocyanuric acid compounds according to claim 1, wherein the trialkyl cyanurate is trimethyl cyanurate, triethyl cyanurate, triisopropyl cyanurate, triallyl cyanurate, or trimethallyl cyanurate. .   The method for synthesizing disubstituted isocyanuric acid compounds according to claim 1, wherein the alkyl halide is allyl bromide, allyl chloride, or methallyl chloride.   The method for synthesizing disubstituted inocyanuric acid compounds according to claim 1, wherein the aprotic polar organic solvent is selected from the group consisting of dimethyl sulfoxide, dimethylformamide, dimethylacetamide, 1-methyl-2-pyrodinone and dimethylimidazolidinone.   The method for synthesizing disubstituted isocyanuric acid compounds according to claim 1, wherein the alkali hydroxide is selected from the group consisting of sodium hydroxide, potassium hydroxide and lithium hydroxide.