JPH10195087A - Phosphonic acid derivative and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject new compound having two pieces of carboxyl respectively formable of an ester, useful as a monomer for producing a polyester, etc., and also useful as a transparentizing agent for various polymers or resins. SOLUTION: This compound is 2,5-dicarboxyphenyl phosphonic acid expressed by the formula. The compound is obtained as follows: as first, a reaction liquid phase is formed in a reaction zone by supplying 2,5-dialkylphenyl phosphonic acid (preferably 2,5-dimetlylphenyl phosphonic acid), a solvent (preferably acetic acid), a cobalt salt, a manganese salt and/or a cerium salt and bromine or a bromine compound (preferably hydrogen bromide, etc.). Further, an oxidation reaction is performed by supplying oxygen into the reaction liquid phase by bringing an oxygen gas-containing gas into contact with the reaction zone. Preferably, the oxidation reaction is performed at 120-300 deg.C under an oxygen partial pressure of 2-50-atm under stirring. the reaction usually be finished in 1-20hrs.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a novel compound 2,
The present invention relates to 5-dicarboxyphenylphosphonic acid and a method for producing the same.

[0002]

2. Description of the Related Art Japanese Patent Publication No. 44-24688 discloses that
A modified polyethylene terephthalate having 3,5-dicarboxyphenylphosphonic acid as a copolymer component is disclosed.

[0003]

[Problems to be solved by the invention] Japanese Patent Publication No. 44-246
No. 88 does not disclose 2,5-dicarboxyphenylphosphonic acid and does not disclose a method for producing 3,5-dicarboxyphenylphosphonic acid. An object of the present invention is to provide 2,5-dicarboxyphenylphosphonic acid and a method for producing the same.

[0004]

Means for Solving the Problems 2,5-Dicarboxyphenylphosphonic acid of the present invention has 2,5-dicarboxyphenylphosphonic acid in a reaction zone.
Supplying a dialkylphenylphosphonic acid, a solvent, a cobalt salt, a manganese salt and / or a cerium salt, and bromine or a bromine compound to form a reaction liquid phase, and supplying an oxygen-containing gas to the reaction zone. By supplying and bringing the oxygen-containing gas into contact with the reaction liquid phase, oxygen can be produced by a method comprising supplying oxygen to the reaction liquid phase.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The two alkyl groups of the starting material 2,5-dialkylphenylphosphonic acid are not particularly limited, and may be different or identical, and may have a branched chain. Examples of preferred alkyl groups include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, n-pentyl and the like, and examples of preferred 2,5-dialkylphenylphosphonic acids are 2,5 -Dimethylphenylphosphonic acid, 2-methyl-5-ethylphenylphosphonic acid, 2-methyl-5
-Propylphenylphosphonic acid, 2-ethyl-5-methylphenylphosphonic acid, 2-propyl-5-methylphenylphosphonic acid, 2,5-diethylphenylphosphonic acid, 2,5-dipropylphenylphosphonic acid and the like. . In particular, 2,5-dimethylphenylphosphonic acid is more preferable from a commercial viewpoint.

[0006] 2,5-dialkylphenylphosphonic acid can be prepared, for example, by heating a mixture of 2,5-dialkylbenzenephosphonothioic dichloride and water under reflux, or 2,5-dialkylbenzenephosphonothioic dichloride. By adding dilute nitric acid to the benzene solution and heating the mixture at 30 to 80 ° C.
It can be produced by a method in which 2,5-dialkylbenzenephosphonothioic dichloride is hydrolyzed. The 2,5-dialkylbenzenephosphonothioic dichloride can be produced, for example, by a method in which 1,4-dialkylbenzene and phosphorus sulfide are heated at a temperature of about 50 to 200 ° C. in the presence of aluminum chloride as a catalyst. it can.

As another example of the method for producing 2,5-dialkylphenylphosphonic acid, 2,5-dialkylbenzene bromide is reacted with trimethyl phosphite in the presence of nickel as a catalyst to give 2,5-dialkylphenylphosphonic acid.
A dimethyl ester of 5-dialkylphenylphosphonic acid is prepared, and a mixture of the dimethyl ester of 2,5-dialkylphenylphosphonic acid and hydrochloric acid is heated under reflux to hydrolyze the dimethyl ester of 2,5-dialkylphenylphosphonic acid. There is a method of causing decomposition.

The metal salt may be a cobalt salt, a manganese salt and / or a cerium salt, such as a mixture of a cobalt salt, a manganese salt and a cerium salt, a mixture of a cobalt salt and a manganese salt, or a mixture of a cobalt salt and a cerium salt. A mixture with is used. This metal salt is used in a ratio of 0.01 to 20 mol%, preferably 2 to 10 mol%, based on 2,5-dialkylphenylphosphonic acid.

Examples of cobalt salts include cobalt formate,
Cobalt salts of fatty acids such as cobalt acetate, cobalt octylate or cobalt naphthenate; chelate compounds of cobalt such as cobalt acetylacetonate; cobalt of inorganic acids such as cobalt chloride, cobalt bromide, cobalt iodide or cobalt carbonate. And the like. Examples of manganese salts include manganese formate, manganese acetate, manganese salts of fatty acids such as manganese octylate or manganese naphthenate, chelate compounds of manganese such as manganese acetylacetonate, manganese chloride, manganese bromide, manganese iodide Or a manganese salt of an inorganic acid such as manganese carbonate. Examples of cerium salts include:
Cerium salts of fatty acids such as cerium formate, cerium acetate, cerium octoate or cerium naphthenate; chelate compounds of cerium such as cerium acetylacetonate; inorganics such as cerium chloride, cerium bromide, cerium iodide or cerium carbonate Cerium salts of acids and the like. These cobalt salts, manganese salts, cerium salts and the like can be used alone or as a mixture of two or more.

The bromine compound is not particularly limited, and various bromine compounds can be used. Preferred examples thereof include hydrogen bromide and salts thereof, such as ammonium bromide, sodium bromide and potassium bromide. Is mentioned. Bromine, these bromine compounds and the like can also be used as one or a mixture of two or more thereof, and 0.1 to 20% by mole, based on 2,5-dialkylphenylphosphonic acid,
Preferably, it is used in a ratio of 1 to 20 mol%. Also,
The ratio of the mole% of bromine or bromine compound used to 2,5-dialkylphenylphosphonic acid is preferably larger than the ratio of the mole% of the metal salt used to 2,5-dialkylphenylphosphonic acid. .

As the solvent, an alkanoic acid having 1 to 3 carbon atoms is preferable, and examples thereof include formic acid, acetic acid and propionic acid. Acetic acid is more preferred from a commercial viewpoint. This solvent is used in an amount of 1 to 100 times by weight, preferably 5 to 2,5-dialkylphenylphosphonic acid.
Used in an amount of up to 20 times by weight. The oxygen gas-containing gas may be a gas consisting of only oxygen gas, but is preferably a mixed gas of oxygen gas and another inert gas, for example, a nitrogen gas, or air.

The reaction liquid phase is formed in a reaction zone, for example, a reactor, in the above ratio, in the above ratio, with a cobalt salt, a manganese salt and / or a cerium salt, a bromine or a bromine compound, a solvent, a 2,5-dialkylphenylphosphonic acid. And is supplied. An oxygen gas-containing gas is supplied to the reaction zone,
The gas contacts the reaction liquid phase to supply oxygen in the gas to the reaction liquid phase. The oxygen supplied from the oxygen gas-containing gas oxidizes the 2,5-dialkylphenylphosphonic acid in the reaction liquid phase, and as a result,
5-Dicarboxyphenylphosphonic acid is formed. The metal salt and bromine or bromine compound supplied to the reaction liquid phase contribute to the formation of a catalyst that promotes the oxidation reaction in the reaction liquid phase.

The oxidation reaction in the reaction liquid phase is carried out preferably at 100 to 350 ° C., preferably 120 to 30 ° C., with stirring.
At a temperature of 0 ° C. and from normal pressure to 400 atm, preferably 1
The reaction can be carried out under the pressure of an oxygen gas-containing gas at 0 to 100 atm, particularly under a partial pressure of oxygen of normal pressure to 80 atm, preferably 2 to 50 atm. The formation of the reaction liquid phase and the supply of the oxygen gas-containing gas can be performed by either a continuous method or a batch method. Usually, this oxidation reaction can be completed in about 1 to 20 hours.

[0014]

【Example】

Example 1 42.6 g of p-xylene, 180 g of phosphorus sulphate,
40 g of aluminum chloride were charged into a glass reactor, and the mixture in the reactor was heated at 80 ° C. for 3 hours with stirring. After completion of the heating, the content in the reactor was cooled to room temperature, and then water and n-heptane were added to the reactor, stirred, and allowed to stand, thereby forming an aqueous layer and an n-heptane layer. Separated. The n-heptane layer was further washed with water and distilled to obtain a solution under reduced pressure of 0.3 mmHg.
At 40 ° C., 30 g of a fraction was recovered as 2,5-dimethylbenzenephosphonothioic dichloride.

Into a glass reactor, 30 g of the recovered
Of 2,5-dimethylbenzenephosphonothioic dichloride, 100 g of benzene, and 50 g of water were charged and heated under stirring to bring the liquid temperature in the reactor to 50 ° C. Next, 63% by weight was added to the stirred liquid in the reactor.
After a small amount of nitric acid was added dropwise to observe the heat generation of the liquid in the reactor and the generation of nitrogen oxide gas, the dropwise addition of the nitric acid was continued little by little to complete the dropwise addition of the nitric acid in a total amount of 40 g. . After the addition of the nitric acid, the liquid in the reactor was further stirred for 3 hours, and then the liquid in the reactor was cooled to 10 ° C. Crystals were precipitated by this cooling. The contents in the reactor were passed through a filter, water was poured into the filter to wash the crystals on the filter medium, and then dried to obtain 16.5 g of a solid as 2,5-dimethylphenylphosphonic acid. . This yield was calculated to be 67.7% based on 2,5-dimethylbenzenephosphonothioic dichloride.

5.58 g of the obtained 2,5-dimethylphenylphosphonic acid, 0.3 g of cobalt acetate tetrahydrate, 0.074 g of manganese acetate tetrahydrate, and 0.41 g of
g of a 47% by weight aqueous solution of hydrogen bromide and 55 g of acetic acid were placed in a 100 ml titanium autoclave. Nitrogen gas was introduced into the autoclave until the internal pressure reached 70 atm, and then oxygen gas was introduced until the internal pressure reached 100 atm. Under stirring of the liquid in the autoclave, the temperature of the contents is brought to 220 ° C. by heating the autoclave, and the pressure in the autoclave is raised to 10 ° C. by continuing to supply oxygen gas.
Maintained at 0 atm for 8 hours. Immediately stop this heating,
The autoclave was cooled to room temperature.

After releasing the pressure in the autoclave, the contents are taken out from the autoclave, filtered, and acetic acid is poured into the precipitated solid on the filter medium for washing.
When the precipitated solid was dried, 4.5 g of a precipitated solid was obtained. The precipitated solid was purified by using a silica gel column and developing with a mixed solution of 70% by weight of methanol and 30% by weight of acetic acid to obtain 3.4 g of white crystals having a melting point of 288 to 290 ° C. Was. This yield was calculated to be 47.4% based on the starting dimethylphenylphosphonic acid.

This white crystal shows an absorption based on a carbonyl group at 1690 cm ^-1 in infrared absorption analysis, shows a peak based on carbon atoms of two kinds of carbonyl groups in nuclear magnetic resonance analysis, and shows 39.1 carbon atoms in elemental analysis.
% Of hydrogen, 2.9% by weight of hydrogen and 12.5% by weight of phosphorus, and showed no parent peak in mass spectrometry, but showed a peak with a molecular weight of 229. The result of the elemental analysis was 39.0% by weight of carbon and 2.9% of hydrogen calculated from the chemical formula of 2,5-dicarboxyphenylphosphonic acid.
The content was in good agreement with the respective contents of 1% by weight and 12.6% by weight of phosphorus.

Separately, methylated products obtained from the above white crystals by a methylation method using diazomethane show peaks based on methyl groups at four positions in nuclear magnetic resonance analysis,
Mass spectrometry showed the presence of a substance having a molecular weight of 302. Therefore, the molecular weight of the substance having a molecular weight of 302 before methylation is calculated as 246,
It can be seen that it is consistent with the molecular weight of 5-dicarboxyphenylphosphonic acid.

From the results of these analyses, the compound of white crystals was found to have the following formula

[0021]

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The methylated 2,5-dicarboxyphenylphosphonic acid represented by the above formula and having a molecular weight of 302 is represented by the following formula:

[0023]

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The tetramethyl ester of 2,5-dicarboxyphenylphosphonic acid represented by Example 2 5.58 g of 2,5-dimethylphenylphosphonic acid obtained in the same manner as in Example 1, 0.3 g of cobalt acetate tetrahydrate, 0.05 g of cerium acetate monohydrate and 0% .4
1 g of a 47% by weight aqueous solution of hydrogen bromide and 55 g of acetic acid were charged into the same autoclave as used in Example 1. Nitrogen gas was introduced into the autoclave until the internal pressure reached 70 atm, and then oxygen gas was introduced until the internal pressure reached 100 atm. Under agitation of the liquid in the autoclave, the temperature of the content was raised to 250 ° C. by heating the autoclave, and the pressure in the autoclave was raised to 100 ° C. by continuing to supply oxygen gas.
Atmospheric pressure was maintained for 10 hours. Immediately stop this heating,
The autoclave was cooled to room temperature.

After releasing the pressure in the autoclave, the content was taken out from the autoclave, filtered, and acetic acid was poured into the precipitated solid on the filter medium for washing.
When this precipitated solid was dried, 5.0 g of a precipitated solid was obtained. Example 3 5.58 g of 2,5-dimethylphenylphosphonic acid obtained in the same manner as in Example 1, 0.3 g of cobalt acetate tetrahydrate, 0.07 g of manganese acetate tetrahydrate, .5
g of liquid bromine and 55 g of acetic acid were charged to the same autoclave used in Example 1. Nitrogen gas was introduced into the autoclave until the internal pressure reached 70 atm, and then oxygen gas was introduced until the internal pressure reached 100 atm. By heating the autoclave while stirring the liquid in the autoclave, the temperature of the contents was raised to 2 times.
The pressure in the autoclave was maintained at 50 ° C. and the above-mentioned pressure of 100 atm for 10 hours by continuing the supply of oxygen gas. The heating was immediately stopped, and the autoclave was cooled to room temperature.

After releasing the pressure in the autoclave, the content was taken out of the autoclave, filtered, and acetic acid was poured into the precipitated solid on the filter medium for washing.
When this precipitated solid was dried, 5.0 g of a precipitated solid was obtained. Example 4 203.4 g of bis (hydroxyethyl) terephthalate (0.08 mol), 66.45 g of terephthalic acid (0.40 mol) and 37.22 g of ethylene glycol (0.60 mol) Charged into a glass reaction vessel,
Next, the mixture in the reactor was heated at 260 ° C. for 3 hours with stirring under a nitrogen atmosphere and normal pressure to obtain an esterification reaction product.

Then, in the reactor, the esterification reaction product and 18.25 g of 2,5-dicarboxyphenylphosphonic acid (74 mmol, 1.0% by weight as a phosphorus atom with respect to the formed polyester resin). ) And 0.14
g of antimony trioxide (0.5 mmol) and 0.01 g
5 g of cobalt acetate tetrahydrate (0.06 mmol) was charged, and the mixture was heated at 270 ° C. for 3 hours with stirring at normal pressure. Then, gradually reduce the pressure while stirring, and finally reduce the pressure to 40 mm.
Hg was heated at 280 ° C. for 1 hour to carry out polycondensation to obtain a polyester resin product.

The intrinsic viscosity [η] of the obtained resin was measured at a temperature of 25 ° C. using an equal weight mixture of phenol and 1,1,2,2-tetrachloroethane as a solvent. The intrinsic viscosity [η] was 0.72. The flame retardancy of the obtained resin was evaluated by molding the resin into a test piece and measuring the flame retardancy index (oxygen index: OI) of the test piece according to the flame retardancy test method (JIS D1201). . The oxygen index indicating the self-extinguishing property needs to be 22 to 23 or more, and when higher flame retardancy is required, 27 to 28 or more is required. The resulting resin had an oxygen index of 30.3, indicating high flame retardancy.

[0029]

EFFECTS OF THE INVENTION 2,5-Dicarboxyphenylphosphonic acid can be easily obtained by oxidizing a starting material, 2,5-dialkylphenylphosphonic acid, with oxygen in the presence of a catalyst. Can be used. 2,5-Dicarboxyphenylphosphonic acid has two carboxyl groups that can form an ester. Therefore, a polyester can be produced by a polycondensation reaction between a polyhydric alcohol such as ethylene glycol and 2,5-dicarboxyphenylphosphonic acid. And the polyester shows reactivity by the hydroxyl group of the phosphonic acid contained in the ratio of two per two ester groups, for example, by bonding with the molecule of the reactive dye,
Produces colored polyester. Phosphorus atoms contained in the polyester also impart flame retardancy to the polyester. The polyester can also be used as an additive to other polymers. 2,5-Dicarboxyphenylphosphonic acid produces epoxy resins by reaction with epoxy compounds and polyamides by reaction with polyisocyanates. Thus, 2,5-dicarboxyphenylphosphonic acid is not only used as a monomer for forming a polymer,
2,5-Dicarboxyphenylphosphonic acid itself can be used as an additive such as a clarifying agent for various polymers and resins, and a flame retardant.

Claims (4)

[Claims] 1. A 2,5-dicarboxyphenylphosphonic acid. 2. A reaction liquid phase is formed by supplying 2,5-dialkylphenylphosphonic acid, a solvent, a cobalt salt, a manganese salt and / or a cerium salt, and bromine or a bromine compound to the reaction zone. Supplying oxygen gas to the reaction liquid phase by supplying an oxygen gas-containing gas to the reaction zone and contacting the reaction liquid phase with the oxygen gas-containing gas. A method for producing phenylphosphonic acid. 3. The method according to claim 2, wherein the 2,5-dialkylphenylphosphonic acid is 2,5-dimethylphenylphosphonic acid.
The method for producing 2,5-dicarboxyphenylphosphonic acid described in 1 above. 4. The method according to claim 2, wherein the solvent is acetic acid.
The method for producing 2,5-dicarboxyphenylphosphonic acid described in 1 above.