JP2000026482A - Production of phosphoric ester - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a phosphoric ester containing small amount of a pyrophosphate form, from a hydroxy compound having a carboxylic ester or amide, and a polymerizable carbon-carbon double bond. SOLUTION: A compound of formula I (X is O or NH; R1 is H or methyl; R2 is a 1-40C divalent hydrocarbon or the like) is reacted with a phosphorus oxyhalide, and the obtained product is hydrolyzed under an alkaline condition to provide the objective phosphoric ester of formula III having <=5 wt.% content of a compound of formula IV.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a dispersant, an adhesive,
The present invention relates to a method for producing a phosphate ester, which is a raw material for producing a phosphate group-containing polymer used for a tooth coating agent.

[0002]

2. Description of the Related Art When phosphorylating a compound having a polymerizable carbon-carbon double bond, it is necessary to phosphorylate under mild conditions in order to prevent decomposition of the product. As described in JP-A-63-13436, phosphorus oxychloride is used as a phosphorylating agent. For example, when a phosphoric acid group-containing monomer having a (meth) acrylate group is produced using phosphorus oxychloride, the reaction proceeds in two steps as shown in the following reaction formula.

[0003]

Embedded image

(In the formula, R ¹ represents a hydrogen atom or a methyl group. R ² may be substituted with a halogen atom, a hydroxyl group, an amino group or a carboxyl group, and may be an ether type, a thioether type, an ester type, or a thioester type. Represents a divalent hydrocarbon group having 1 to 40 carbon atoms into which a bond of any type selected from the group consisting of thiocarbonyl type, amide type, urethane type, carbonyl type and sulfonyl type may be inserted. ) Usually, when the intermediate (b) is hydrolyzed,
Add not less than 10 ° C. and not less than 2 equivalents of phosphorus oxychloride water used for phosphorylation. In some cases, in order to trap generated hydrochloric acid, an organic base such as pyridine or triethylamine or an inorganic base such as sodium hydroxide may be added in an amount equivalent to hydrochloric acid generated.
If the temperature in the system exceeds 10 ° C. during the hydrolysis of the intermediate (b), a compound (pyro-form, d) in which two molecules of the target product (c) are condensed is produced in an amount of 20% by weight or more. However, even if care is taken that the temperature in the system does not exceed 10 ° C.,
Produces at least 10% by weight.

When a phosphoric acid group-containing monomer having a (meth) acrylic acid ester group is synthesized by this method, the pyro-form has two polymerizable groups in one molecule. If the content is large, gelation occurs during polymerization, for example, in aqueous solution polymerization, which causes troubles in production. In addition, problems such as the inability to obtain a fluid polymer solution occur. In order to avoid such a problem, it is necessary to minimize the content of the pyro-form in the monomer.

Accordingly, an object of the present invention is to provide a method for producing a phosphoric acid ester having a particularly small amount of a pyro compound from a carboxylic acid ester or amide or a hydroxy compound having a polymerizable carbon-carbon double bond.

[0007]

The present invention provides a compound represented by the general formula (I):

[0008]

Embedded image

(Wherein X represents —O— or —NH—, and R ¹ and
R ² has the above-mentioned meaning. ) Is reacted with a phosphorus oxyhalide to form a compound of the general formula (II)

[0010]

Embedded image

(Wherein, X, R ¹ and R ² have the above-mentioned meanings,
E represents a halogen atom. ) And hydrolyzes the compound represented by the general formula (II) under alkaline conditions, the content of the compound represented by the general formula (IV) (the following formula:
(Defined by (A)) is 5% by weight or less of the phosphate ester represented by the general formula (III).

[0012]

(Equation 2)

[0013]

Embedded image

(Wherein, X, R ¹ and R ² have the same meanings as described above)

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION In the compound (I) used in the present invention, the divalent hydrocarbon group represented by R ² includes the following Z ¹
To Z ⁷ are exemplified, preferably a straight-chain alkylene group having 2 to 20 carbon atoms.

Z ¹ : a linear or branched alkylene group having 1 to 40 carbon atoms which may be substituted with a halogen atom, a hydroxyl group, an amino group or a carboxyl group Z ² : a halogen atom, a hydroxyl group, an amino group or a carboxyl group A linear or branched alkenylene group having 2 to 40 carbon atoms which may be substituted with Z ³ :-(AO) _q- (A is an alkylene group having 2 to 3 carbon atoms, q
Represents the number of 1 to 20, and a plurality of A may be the same or different. )

[0017]

Embedded image

(R ³ represents a divalent hydrocarbon group having 1 to 20 carbon atoms which may be substituted by a halogen atom, and Y represents -O-, -C
OO-, -CONH-, -OCONH- or -CO-, and r represents 0 or 1. )

[0019]

Embedded image

[0020]

Embedded image

[0021]

Embedded image

(B is an alkylene group having 2 to 3 carbon atoms; R ⁴ is an alkylene group having 1 to 10 carbon atoms which may be substituted with a halogen atom;
The valent hydrocarbon group, s and t each represent a number of 1 to 20, and a plurality of Bs may be the same or different. Preferred examples of the compound (I) used in the present invention are shown below. Of these, compounds in which X is -O-, R ¹ is a methyl group, and R ² is a linear alkylene group having 2 to 20 carbon atoms are particularly preferred.

[0023]

Embedded image

Compound (I) can be prepared by reacting diol (j) with (meth) acrylic acid, its anhydride or acid chloride, or (meth) acrylamide as shown in the following reaction formula.
It is generally synthesized from (i), but it is difficult to obtain the desired compound (I) alone, and a mixture with di (meth) acrylate or di (meth) acrylamide (k) is used. Often get. Before performing the phosphorylation of the present invention,
The desired compound (I) can be prepared by the method described in JP-A-7-267897.
Compound (I) and diester or diamide (k) may be isolated and purified by the method described in JP-B-2-51437.
The phosphoric acid ester (III) and the diester or diamide (k) may be separated after the phosphorylation.

[0025]

Embedded image

(Wherein R ¹ , R ² and X have the same meanings as above, and D is OH, Cl, NH ₂ or

[0027]

Embedded image

The phosphorus oxyhalide used in the present invention is preferably phosphorus oxychloride. The amount of compound (I) 1
The amount is preferably 1 to 2 mol per mol. The solvent used for phosphorylation is not limited as long as the compound (I) and phosphorus oxyhalide are dissolved and inactive, but tetrahydrofuran, chloroform, methylene chloride, ethyl ether and dimethoxyethane are preferred. Alternatively, the reaction may be performed without a solvent.

In the phosphorylation of the present invention, it is preferable to add a trapping agent for trapping the generated hydrogen halide gas. Examples of the trapping agent include organic tertiary amines such as triethylamine, tripropylamine, tributylamine, pyridine and picoline, alkalis such as sodium hydroxide and potassium hydroxide, sodium perchlorate, potassium perchlorate, sodium carbonate, and carbonate. Salts such as potassium, sodium hydrogen carbonate, sodium hydrogen phosphate, sodium acetate, sodium citrate, sodium glutamate, sodium succinate, and sodium dichloroacetate are exemplified, and organic tertiary amines are preferred. Phosphorylation may be performed without using a trapping agent.

In the phosphorylation, the compound (I) and the trapping agent may be added dropwise after the phosphorus oxyhalide and the reaction solvent are put in a reaction vessel in advance and cooled to a predetermined temperature.
Alternatively, phosphorus oxyhalide and compound (I) may be placed in a reaction vessel, and after cooling to a predetermined temperature, a trapping agent may be dropped. In any case, it is preferable to cool the inside of the reaction system to -60 to -30C before phosphorylation so that the temperature does not exceed -20C during the reaction.

In the case of phosphorylation, if water is present in the system, a pyro-form compound (IV) is formed. Therefore, the total amount of water in the solvent used for the reaction with the raw materials is preferably 3 mol% or less based on the compound (I).

Next, the compound (II) obtained by the above phosphorylation is hydrolyzed under alkaline conditions. The alkaline condition is preferably pH 9 or more, more preferably pH 10 or more, particularly
pH 11 or higher is preferred. In order to achieve alkaline conditions, it is preferable to add an alkali substance of 3 equivalents or more of the phosphorus oxyhalide used for phosphorylation. Examples of the alkaline substance to be used include hydroxides of alkali metals such as sodium hydroxide and potassium hydroxide, hydroxides of alkaline earth metals such as magnesium hydroxide, etc., with sodium hydroxide being particularly preferred. The hydrolysis is performed by adding 1 to 5 times the amount of water necessary for completing the hydrolysis. The hydrolysis temperature is preferably -10 to 10 ° C, and the reaction time is suitably 1 to 4 hours. After the reaction, the pH of the system is adjusted using an acid such as hydrochloric acid.
Is adjusted to 2 or less, and the desired phosphate ester is
(III) is extracted. Examples of the solvent used here include chloroform, methylene chloride, carbon tetrachloride, ethyl ether, ethyl acetate, toluene, benzene and the like.

According to the method of the present invention, a phosphate (III) having a content of the compound (IV) defined above of 5% by weight or less can be obtained.

[0034]

According to the present invention, a phosphoric ester (III) having a compound (IV) content of 5% by weight or less can be obtained. When the phosphoric ester (III) obtained in the present invention is used as a monomer in polymerization, the resulting polymer has a small crosslinked structure and does not cause gelation, and is particularly effective when copolymerized at a high ratio. .

[0035]

EXAMPLES Preparation Example 1 140 g (1.6 mol) of methacrylic acid, 1,6-hexanediol 15
4 g (1.3 mol), p-toluenesulfonic acid 15 g, 2,2′-methylenebis (4-ethyl-tert-butylphenol) 0.6 g
Into a 500 ml four-neck flask under reduced pressure (0.0066 to 0.013 M
Pa) at 90 ° C., and water was distilled off for 1.5 hours while blowing oxygen. After the reaction, 300 ml of hexane was added, the reaction solution was cooled to room temperature, and left at about 5 ° C. overnight. Deposited
1,6-Hexanediol was removed by filtration, the filtrate was transferred to a separating funnel, and washed with aqueous sodium hydrogen carbonate, and the washing was repeated until the washing liquid showed alkalinity. Further, it was washed with ion exchanged water. The organic phase was transferred to a beaker and dried over anhydrous sodium sulfate. After drying, the crude product obtained using a rotary evaporator was purified by silica gel chromatography (chloroform: methanol = 20: 1). Hydroquinone monomethyl ether (20 mg) was added, and the mixture was concentrated under reduced pressure. The amount of the obtained methacrylic acid monoester of 1,6-hexanediol was 144 g. The purity was 97% or more by liquid chromatography.

Example 1 36.8 g (0.24 mol) of phosphorus oxychloride was dissolved in 70 ml of ethyl ether, placed in a 300 ml four-necked reaction vessel, and cooled to -20 to -30 ° C. 37.2 g (0.2 mol) of 1,6-hexanediol methacrylic acid monoester synthesized in Production Example 1 and 24.2 g (0.24 mol) of triethylamine were dissolved in 70 ml of ethyl ether, placed in a dropping funnel, and connected to a reaction vessel. The phosphorus oxychloride solution was stirred, and a solution of methacrylic acid monoester of 1,6-hexanediol and triethylamine was added dropwise over about 2 hours while blowing dry nitrogen gas. After the dropwise addition, the mixture was stirred for 3 hours while being careful not to exceed -20 ° C to synthesize a phosphate ester intermediate. Then-
The temperature was raised to 5 ° C, and 25 g of a 48% aqueous NaOH solution was gradually added so that the liquid temperature did not exceed 10 ° C. The pH at this time was 14. Thereafter, stirring was performed at 0 to 10 ° C. for 3 hours. 200 ml of the liquid
In ion-exchanged water, placed in a separating funnel, and washed three times with chloroform. Next, a 6N hydrochloric acid aqueous solution was added to the aqueous solution until the pH became 1 or less. Extraction was performed three times from the aqueous solution with ethyl acetate.The obtained ethyl acetate solution was collected, dried over sodium sulfate, added with 20 mg of hydroquinone monomethyl ether, and concentrated under reduced pressure to obtain 46.5 g of a pale yellow liquid.
I got

The liquid was used as a 10% d ₆ -dimethyl sulfoxide solution, and 81 MHz ³¹ P-NMR was measured.
And the signal of the pyro-form of the phosphoric acid monoester was confirmed at −8.0 ppm.
Calculated from the integral ratio, the weight ratio between the phosphoric acid monoester and its pyro-isomer was 96: 4. The liquid was analyzed by liquid chromatography (column: LiChrosher100 RP-18, manufactured by Merck, detection UV). As a result, the purity was 91 to 93%.

Production Example 2 A production method was carried out in the same manner as in Production Example 1 except that 258 g (1.3 mol) of 1,12-dodecanediol was used instead of 154 g (1.3 mol) of 1,6-hexanediol. 229 g of methacrylic acid monoester of 1,12-dodecanediol were obtained. The purity was 97% or more by liquid chromatography.

Example 2 Phosphorus oxychloride (36.8 g, 0.24 mol) was mixed with 1,2 obtained in Production Example 2.
Methacrylic acid monoester of 12-dodecanediol 37.2
Using g (0.2 mol), a phosphate ester intermediate was synthesized in the same manner as in Example 1. Thereafter, the temperature was raised to −5 ° C., and 48% Na
25 g of an OH aqueous solution was gradually added so that the liquid temperature did not exceed 10 ° C. The pH at this time was 14. Thereafter, stirring was performed at 0 to 10 ° C. for 3 hours. The liquid was dispersed in 200 ml of ion-exchanged water, placed in a separating funnel, and washed three times with chloroform. Next, a 6N hydrochloric acid aqueous solution was added to the aqueous solution until the pH became 1 or less. The aqueous solution was extracted three times with ethyl acetate. The obtained ethyl acetate solution was collected, dried over sodium sulfate, added with 20 mg of hydroquinone monomethyl ether, and concentrated under reduced pressure to obtain 56.1 g of a pale yellow liquid.

The liquid was used as a 10% d ₆ -dimethylsulfoxide solution, and measured by 200 MHz ¹ H-NMR.
Phosphoric acid proton signal near 3 ppm for 3H, 6.0p
Ethylene protons at 1pm each at pm and 5.7ppm, 3.
A signal of 24 H of the dodecamethylene group was confirmed at 7 to 4.2 ppm and 1.2 to 1.6 ppm, and a signal of 3 H of the methyl proton was confirmed at 1.9 ppm, confirming that the compound was methacryloyl oxide decyl dihydrogen phosphate.

The liquid was used as a 10% d ₆ -dimethyl sulfoxide solution, and 81 MHz ³¹ P-NMR was measured.
And the signal of the pyro-form of the phosphoric acid monoester was confirmed at -7.9 ppm.
Calculated from the integral ratio, the weight ratio of the phosphoric acid monoester to its pyro-isomer was 96: 4. As a result of analyzing the liquid by liquid chromatography, the purity was 92 to 94%.

Example 3 Phosphorous oxychloride (36.8 g, 0.24 mol) was dissolved in 70 ml of ethyl ether, placed in a 300 ml four-necked reaction vessel, and cooled to -20 to -30 ° C. 37.2 g (0.2 mol) of methacrylic acid monoester of 1,6-hexanediol synthesized in Production Example 1 was dissolved in 70 ml of ethyl ether, placed in a dropping funnel, and connected to a reaction vessel. The phosphorus oxychloride solution was stirred, and the above-mentioned methacrylic acid monoester solution of 1,6-hexanediol was dropped in about 2 hours while blowing dry nitrogen gas. After the dropwise addition, the mixture was stirred for 3 hours while being careful not to exceed -20 ° C to synthesize a phosphate ester intermediate. Then-
The temperature was raised to 5 ° C, and 25 g of a 48% aqueous NaOH solution was gradually added so that the liquid temperature did not exceed 10 ° C. The pH at this time was 14. Thereafter, stirring was performed at 0 to 10 ° C. for 3 hours. 200 ml of the liquid
In ion-exchanged water, placed in a separating funnel, and washed three times with chloroform. Next, a 6N hydrochloric acid aqueous solution was added to the aqueous solution until the pH became 1 or less. The aqueous solution was extracted three times with ethyl acetate, the obtained ethyl acetate solution was collected, dried over sodium sulfate, added with 20 mg of hydroquinone monomethyl ether, and concentrated under reduced pressure to obtain 47.2 g of a pale yellow liquid.
I got

The liquid was used as a 10% d ₆ -dimethylsulfoxide solution, and 81 MHz ³¹ P-NMR was measured.
And the signal of the pyro-form of the phosphoric acid monoester was confirmed at −8.0 ppm.
Calculated from the integral ratio, the weight ratio between the phosphoric acid monoester and its pyro-isomer was 97: 3. As a result of analyzing the liquid by liquid chromatography, the purity was 92 to 94%. Comparative Example 1 A phosphate ester intermediate was synthesized in the same manner as in Example 1. Thereafter, the temperature was raised to 0 ° C., and 20 g of ion-exchanged water was gradually added so that the temperature did not rise rapidly. Subsequently, 48.5 g (0.4 mol) of triethylamine was dissolved in 70 ml of ethyl ether and added dropwise. The pH at the end of the dropwise addition was 7.5. afterwards
The reaction was kept at 0 ° C. for 10 hours and stirring was continued. Thereafter, 20 mg of hydroquinone monomethyl ether was added, and ethyl ether was distilled off under reduced pressure. The liquid was dispersed in 200 ml of ion-exchanged water, and sodium carbonate was added until the liquid became alkaline. Put the aqueous solution in a separating funnel and add chloroform.
Washing was performed twice. Next, a 6N hydrochloric acid aqueous solution was added to the aqueous solution until the pH became 1 or less. 3 from the aqueous solution with ethyl acetate
Performed extraction twice, collect the resulting ethyl acetate solution, dry over sodium sulfate, hydroquinone monomethyl ether 20 mg
And concentrated under reduced pressure to obtain 46.1 g of a pale yellow liquid.

The liquid was used as a 10% d ₆ -dimethylsulfoxide solution, and 81 MHz ³¹ P-NMR was measured.
And the signal of the pyro-form of the phosphoric acid monoester was confirmed at −8.0 ppm.
Calculated from the integral ratio, the weight ratio of the phosphoric acid monoester to its pyro form was 85:15. As a result of analyzing the liquid by liquid chromatography, the purity was 80 to 82%.

Claims (4)

[Claims] 1. A compound of the general formula (I) (Wherein, X represents —O— or —NH—; R ¹ represents a hydrogen atom or a methyl group; R ² may be substituted with a halogen atom, a hydroxyl group, an amino group, or a carboxyl group; , A thioether type, an ester type, a thioester type, a thiocarbonyl type, an amide type, a urethane type, a carbonyl type and a carbon number of 1 to 40 which may be inserted into a bond selected from the group consisting of a sulfonyl type. Is reacted with a phosphorus oxyhalide to form a compound represented by the general formula (II): (Wherein X, R ¹ and R ² have the above-mentioned meanings, and E represents a halogen atom), and the compound represented by the general formula (II) is hydrolyzed under alkaline conditions. A method for producing a phosphate ester represented by the general formula (III), wherein the content of the compound represented by the general formula (IV) (defined by the following formula (A)) that decomposes is 5% by weight or less. (Equation 1) Embedded image (In the formula, X, R ¹ and R ² have the same meanings as described above.) 2. The method according to claim 1, wherein the alkaline condition is a condition of pH 9 or more. 3. The reaction temperature at the time of hydrolysis is -10 to 10 ° C.
The method according to claim 1 or 2, wherein 4. X is —O—, R ¹ is a methyl group, R ² is ² carbon atoms.
The process according to any one of claims 1 to 3, wherein the alkylene group is a linear alkylene group of from 20 to 20.