JPH0789928A - Production of aromatic dicarboxylic acid diaryl ester - Google Patents

Abstract

PURPOSE:To provide a method for easily producing an aromatic dicarboxylic acid diaryl ester sulfonic acid salt from inexpensive raw materials by the use of a conventional ester exchange reaction device, the production of the aromatic dicarboxylic acid diaryl ester sulfonic acid salt having been difficult. CONSTITUTION:An aromatic dicarboxylic acid dialkyl ester sulfonic acid salt of formula I (R1, R2 are 1-6C alkyl; M<+> is alkalu metal ion) us reacted with a diaryl carbonate of formula II (R<3> is H, 1-6C alkyl, aryl), preferably diphenyl carbonate, in an amount of 2-3 moles, preferably 2-2.5 moles, per mole of the compound of formula I in the presence of an ester exchange catalyst at 250-320 deg.C, preferably 270-300 deg.C, in a thermally melted state to obtain an aromatic dicarboxylic acid diaryl ester sulfonic acid salt of formula III. The ester exchange catalyst includes all of catalysts used for ordinary ester exchange reactions, and is preferably used in an amount of 0.0003-0.02 mole, especially 0.003-0.01 mole, per mole of the compound of formula I.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for producing an aromatic dicarboxylic acid diaryl ester sulfonate. More specifically, the present invention relates to a method for producing an aromatic dicarboxylic acid diaryl ester sulfonate that is useful as a production intermediate for dyes, high molecular weight polymers, ultraviolet absorbers, pharmaceuticals and the like, or as a high molecular weight polymer modifier.

[0002]

2. Description of the Related Art Such an aromatic dicarboxylic acid diaryl ester sulfonate is described in JP-A-48-12083 for use in a polyamide fiber, and a high molecular weight polymer for improving the dyeing of the polyamide fiber is described. It is used as a coalescing modifier. Further, JP-A-1-111
Japanese Patent No. 035 describes the use of a polyester used as a modifier when producing a water-absorbent composite yarn. However, in any case, there is no description about the method for producing an aromatic dicarboxylic acid diaryl ester sulfonate in the present invention, and although the present agent exerts an excellent modifying effect on a high molecular weight polymer. No, suggesting that there was no suitable manufacturing method. This can be inferred from the following.

Generally, the following method is considered as a method for producing an aromatic dicarboxylic acid aryl ester.
That is, 1) a method of directly esterifying an aromatic dicarboxylic acid and a phenol, 2) a method of reacting an aromatic dicarboxylic acid chloride and a phenol in the presence of a basic compound and a solvent, 3) an aromatic dicarboxylic acid and a diaryl There is a method of heating and melting carbonate in the presence of a catalyst.

Among the above methods, the method 1) has a possibility that an aromatic dicarboxylic acid diaryl ester sulfonate can be produced with an inexpensive raw material. However, in the reaction with an ordinary transesterification catalyst, the reaction temperature is Since the temperature is usually 280 ° C. or higher, the boiling point of phenols under normal pressure is exceeded, and a reaction vessel that can withstand high pressure is required. Moreover, in the case of the aromatic dicarboxylic acid diaryl ester sulfonate, the dicarboxylic acid sulfonate as a raw material has lower solubility and reactivity than dicarboxylic acid, and thus it is necessary to further increase the reaction temperature, and the decomposition reaction, etc. It is easy to cause side reactions.

By the way, in the production of alkyl ester,
A method of reacting a carboxylic acid in an alcohol in the presence of a non-volatile acid such as sulfuric acid is used. However, in the reaction of a carboxylic acid and a phenol, the phenol is subjected to a nucleophilic reaction, and thus the desired ester is used. Can't get

According to the method 2), when a raw material containing a sulfonate is used, it is difficult to produce the acid chloride as the raw material. Even if the acid chloride is obtained, the reaction solvent is used in the subsequent reaction, which is disadvantageous in cost.

The method 3) is usually a method for easily producing a diaryl ester, but in the case of producing an aromatic dicarboxylic acid diaryl ester sulfonate,
The corresponding dicarboxylic acids have very low solubility, which makes them difficult to manufacture.

As another method, 4) a method of sulfonating an aromatic dicarboxylic acid diester can be considered. However, when an aromatic dicarboxylic acid diaryl ester sulfonate is produced, a phenoxy group is more likely to be sulfonated than an aromatic group having a carboxylic acid group, and the intended product cannot be obtained.

[0009]

DISCLOSURE OF THE INVENTION The present invention is to provide a method for producing the above-mentioned aromatic dicarboxylic acid diaryl ester sulfonate, which has not hitherto been effectively produced.

[0010]

The present invention provides an aromatic dicarboxylic acid dialkyl ester sulfonate represented by the following formula (A) and an aromatic dicarboxylic acid dialkyl ester sulfonate 1 in the presence of a transesterification catalyst. Aromatic dicarboxylic acid diaryl represented by the following formula (C), characterized in that 2 to 3 mol of the diaryl carbonate represented by the following formula (B) is melted by heating at 250 ° C. to 320 ° C. It is a method for producing an ester sulfonate.

[0011]

[Chemical 2]

[Wherein R ¹ and R ² are each independently an alkyl group having 1 to 6 carbon atoms, R ³ is a hydrogen atom, and 1 to 6 carbon atoms]
Is an alkyl group or an aryl group, and M ⁺ is an alkali metal ion. The substituents R ¹ and R ² of the aromatic dicarboxylic acid dialkyl ester sulfonate represented by the formula (A) used in the present invention are alkyl groups having 1 to 6 carbon atoms, specifically, methyl ester and ethyl. It is preferable to form an ester. For the production of these aromatic dicarboxylic acid dialkyl ester sulfonates, a conventionally known production method of heating the corresponding aromatic dicarboxylic acid sulfonate in an alcohol in the presence of a non-volatile acidic catalyst such as sulfuric acid is used. Available.

M ⁺ is an alkali metal, and is preferably a sodium salt or potassium salt. Specific examples include 5-sodium sulfo-dimethyl isophthalate, 5
-Diethyl sodium sulfo-isophthalate, 5-potassium sulfo-dimethyl isophthalate, 5-potassium sulfo-isophthalate diethyl, 2-sodium sulfo-terephthalate dimethyl, 2-sodium sulfo-terephthalate diethyl, 2-potassium sulfo-terephthalate Examples thereof include dimethyl acid, 2-potassium sulfo-diethyl terephthalate and the like.

Further, the substituent R ³ as the diaryl carbonate represented by the formula (B) is preferably a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an alkoxy group or an aryl group. Specifically, diphenyl carbonate, bis (2-
Methylphenyl) carbonate, bis (4-methylphenyl) carbonate, bis (2-methoxyphenyl) carbonate, bis (4-methoxydiphenyl) carbonate and the like can be exemplified, but among these, diphenylcarbonate is particularly preferable.

In the present invention, the diaryl carbonate represented by the above formula (B) is used in a proportion of 2 to 3 moles per 1 mole of the aromatic dicarboxylic acid dialkyl ester sulfonate represented by the above formula (A), and more preferably. Two
Use from 2.5 to 2.5 moles. When it is less than 2 mol, the transesterification reaction is incomplete, the ratio of the desired product is not sufficient, and the purification tends to be difficult. There is no particular problem if the amount is more than 3 mol, but a large amount of unreacted material remains after the reaction.

The transesterification catalyst used in the present invention is not particularly limited as long as it can be used in a usual transesterification reaction. Such transesterification catalysts include antimony compounds such as antimony trioxide, stannous acetate, dibutyltin oxide, tin compounds such as dibutyltin diacetate, zinc compounds such as zinc acetate, calcium compounds such as calcium acetate, sodium carbonate, Examples thereof include alkali metal salts such as potassium carbonate.

The amount of the catalyst used is 1 mol of the aromatic dicarboxylic acid dialkyl ester sulfonate,
A ratio of 0.0003 mol to 0.02 mol is preferable,
It is more preferably 0.003 to 0.015 mol.
This amount is larger than the amount used in a normal transesterification reaction, but in the reaction of the present invention, the reaction rate is slow because it is an ester-transesterification reaction, and it is necessary to use more catalyst than in a normal transesterification reaction. Is preferable.

In the present invention, the aromatic dicarboxylic acid dialkyl ester sulfonate represented by the formula (A) and the diaryl carbonate represented by the formula (B) are heated and melted in the presence of the above transesterification catalyst. The aromatic dicarboxylic acid dialkyl ester sulfonate is preferably dried before the reaction. This is because the sulfonate easily absorbs moisture, and thus the diaryl carbonate is prevented from being partially decomposed by the absorbed moisture. Further, it is also preferable to use various additives such as an antioxidant together during the reaction.

The temperature for heating and melting these compounds is preferably 250 ° C. to 320 ° C., and 270 ° C. to 3 ° C.
00 ° C. is more preferable. This is because if the temperature is lower than 250 ° C., the reaction does not proceed, and if the temperature is higher than 320 ° C., side reactions such as decomposition easily occur. Although the reaction time depends on the reaction temperature and the amount of catalyst, it is usually about 1 hour to several tens of hours.

A low boiling distillate is formed with the reaction. The distillate is taken out of the reaction system. This is because the reaction is an equilibrium reaction and the reaction does not proceed unless the distillate is taken out of the reaction system. The low boiling point distillate contains an alkylaryl carbonate or a dialkyl carbonate as a main component, and these are available for production of the diaryl carbonate after recovery.

The reaction can be carried out under pressure or under reduced pressure, but usually under normal pressure or under reduced pressure. Preferably, the reaction is carried out under normal pressure, and when the reaction is almost completed, the reaction is carried out under reduced pressure to distill off unreacted diaryl carbonate.

The product obtained can be used as it is, but it is more preferable to purify it. As a purification method,
Recrystallization is preferred. Purification by distillation is difficult because it contains the sulfonate. As the recrystallization solvent, general solvents such as alcohol solvents such as methanol and ethanol and hydrocarbon solvents such as xylene can be used.

[0023]

According to the present invention, an aromatic dicarboxylic acid diaryl ester sulfonate, which has been difficult to produce although its effectiveness has been heretofore known, can be used in a conventional transesterification reaction using an inexpensive raw material. Since it can be easily manufactured by a device, its industrial significance is extremely large.

[0024]

The present invention will be described in detail below with reference to examples, but the present invention is not limited to the examples. In the examples, "part" means "part by weight".

[0025]

Example 1 177.6 parts of dimethyl 5-sodium sulfoisophthalate, 321 parts of diphenyl carbonate and 1.2 parts of dibutyltin diacetate were charged into a reactor having a stirrer and a distillation system, and the inside of the vessel was replaced with nitrogen. Then, the mixture was heated to 280 ° C. under normal pressure and reacted for 6 hours. Then 4
The pressure was reduced to 00 mmHg to distill off unreacted diphenyl carbonate. The product obtained was recrystallized from methanol. The melting point of the obtained product is from 303 ° C. to 308 ° C., and the ¹ H-NMR spectrum and IR spectrum are shown in FIGS. 1 and 2, respectively.

[0026]

Comparative Example 1 The same reaction as in Example 1 was carried out except that 160.8 parts of 5-sodium sulfoisophthalic acid was used instead of 177.6 parts of dimethyl 5-sodium sulfoisophthalate, and the reaction was carried out at 280 ° C. for 30 hours. Even if it reacts above,
5-Sodium sulfoisophthalic acid did not dissolve and no reaction product was obtained.

From the above, it is understood that the present invention is an effective method for producing an aromatic dicarboxylic acid diaryl ester sulfonate.

[Brief description of drawings]

1 is a ¹ H-NMR spectrum of the product of Example 1. FIG.

2 is an IR spectrum of the product of Example 1. FIG.

Claims (1)

[Claims] 1. An aromatic dicarboxylic acid dialkyl ester sulfonate represented by the following formula (A) in the presence of an ester exchange catalyst, and 2 to 3 mol of the aromatic dicarboxylic acid dialkyl ester sulfonate per 1 mol. The ratio of diaryl carbonate represented by the following formula (B) is 2
A method for producing an aromatic dicarboxylic acid diaryl ester sulfonate represented by the following formula (C), which comprises heating and melting at 50 ° C to 320 ° C. [Chemical 1] [However, R ¹ and R ² each independently represent an alkyl group having 1 to 6 carbon atoms, R ³ represents a hydrogen atom, an alkyl group or aryl group having 1 to 6 carbon atoms, and M ⁺ represents an alkali metal ion. ]