KR102066003B1 - Process for the acidification of terephthalylidene dicamphor sulfonic acid salt - Google Patents

Abstract

The present invention provides a method for acidifying terephthalylidene decamper sulfonate to convert to terephthalylidene decamper sulfonic acid, specifically terephthalylidene decamper sulfonate in the presence of a cation exchange resin. The present invention relates to a method for converting to phonic acid, and the conversion method of the present invention is a very effective method having a high conversion rate in a simple process.

Description

Process for the acidification of terephthalylidene dicamphor sulfonic acid salt}

The present invention relates to a method for acidifying terephthalylidene dicamphor sulfonate, and more particularly, to a method for converting terephthalylidene dicamphor sulfonate to terephthalylidene dicamphor sulfonic acid in the presence of a cation exchange resin.

There are ultraviolet rays A (320-400 nm) and ultraviolet rays B (290-320 nm) in ultraviolet rays, and UV A accounts for over 90% of the ultraviolet rays. UVB is well known as a leading cause of erythema and minor burns during the summer months when sun exposure is frequent, while UVA penetrates into the skin and affects cells, resulting in photoaging, skin allergies and severe skin cancer. have. Therefore, UVA affects the skin regardless of the season, so special care is required.

Most of the currently available materials for organic UV blockers are fat-soluble and have no solubility in water. Therefore, cosmetics manufactured using organic UV blockers currently in circulation have a disadvantage in that the feeling of use is mostly applied to the skin. In addition, inorganic UV blockers are not good enough to apply, so the skin feels thicker when applied.

Meanwhile, terephthalylidene decamper sulfonic acid, which is known from U.S. Patent Nos. 4,585,597 and 5,698,595, protects the skin from ultraviolet rays A and prevents skin aging. The product can be manufactured with a good feeling, and it is easy to clean, which helps to maintain pure skin.

Furthermore, terephthalylidene dicamphor sulfonic acid is a water-soluble organic UV blocker that can be manufactured in various formulations and is distributed in 33% aqueous solution and registered with KFDA as 33% aqueous solution.

Methods for preparing terephthalylidene dicamphor sulfonic acid are known from U.S. Patent Nos. 4,585,597 and 4,588,839. Condensation reaction of 2 moles of 10-dl-camphorsulfonic acid with 1 mole of terephthalaldehyde in the presence of a base as shown in Scheme 1 below. It is known to obtain terephthalylidene dicamphor sulfonate and acidify it with hydrochloric acid to obtain terephthalylidene dicamphor sulfonic acid.

Scheme 1

However, this acidification reaction corresponds to the equilibrium reaction shown in Scheme 2 below.

Scheme 2

Therefore, the acidity of the terephthalylidene dicamphor sulfonate can be made by using an excessive amount of acid, which increases the manufacturing cost and requires a separate process to remove the acid used in excess. There is also a need for another process for removing water-soluble salts, such as NaCl, a byproduct from terephthalylidene decamper sulfonic acid that is soluble in water.

Moreover, the use of substantially excess acid did not complete the acidification to terephthalylidene dicamphor sulfonic acid. In other words, the conventional methods using inorganic or organic acids are complex, and the acidification process is complicated and economically inefficient. The yield of terephthalylidene decamper sulfonic acid is also very low.

Therefore, a study on the acidification method of terephthalylidene dicamphor sulfonate is simple and efficient.

U.S. Patent No. 4,585,597 U.S. Patent No. 5,698,595 U.S. Patent No. 4,588,839

The present inventors have completed the present invention by studying the acidification reaction of terephthalylidene dicamphor sulfonate to solve the above problems.

Accordingly, the present invention provides a method for converting terephthalylidene dicamphor sulfonic acid salt to terephthalylidene dicamphor sulfonic acid with high yield, purity and very economical efficiency in a simple process. .

The present invention provides a method for converting terephthalylidene dicamphor sulfonate to terephthalylidene dicamphor sulfonic acid, which has been improved in yield and purity by a simple process, in the presence of a cation exchange resin. It is characterized in that the terephthalylidene dicamphor sulfonate represented by the formula (2) is converted to the terephthalylidene dicamphor sulfonic acid represented by the formula (1).

[Formula 1]

[Formula 2]

[In Formula 1 and 2,

M is an alkali metal or N (R ¹ ) (R ² ) (R ³ ) (R ⁴ ) and R ¹ to R ⁴ are independently of each other hydrogen or (C 1 -C 7) alkyl;

R is (C1-C7) alkyl or (C1-C7) alkoxy;

n is 0 or an integer of 1 to 4, and when n is 2 or more, R may be different or the same.]

In Formula 2 according to an embodiment of the present invention, M is Na, and n may be 0.

The cation exchange resin according to an embodiment of the present invention may be an H-type cation exchange resin, may be a sulfonated styrene resin crosslinked with divinylbenzene, and may have an ion exchange capacity of 1 to 3 meq / ml.

The conversion method according to an embodiment of the present invention may be an aqueous solution of terphthalylidene dicamphor sulfonate dissolved in terephthalylidene dicamphor sulfonate represented by Formula 2, and an aqueous solution of terphthalylidene dicamphor sulfonate Silver may be prepared using 500 to 1000 parts by weight of water with respect to 100 parts by weight of terephthalylidene dicamphor sulfonate.

In the conversion method of the present invention, by converting terephthalylidene dicamphor sulfonate into terephthalylidene dicamphor sulfonic acid in the presence of cation exchange resin, the conversion rate is very high even in the presence of a small amount of cation exchange resin, and almost all acidification occurs. Removal of the resulting salt is very easy.

In addition, since the conversion method of the present invention is obtained terephthalylidene dicamphor sulfonic acid in an aqueous solution state can easily obtain 33% terephthalylidene dicamphor sulfonic acid aqueous solution can be manufactured as a product that can be immediately distributed without a separate process Do.

In addition, the conversion method of the present invention is a very economical and efficient method because almost all of the conversion to terephthalylidene dicamphor sulfonic acid as well as the used cation exchange resin can be recovered and reused.

The present invention provides a method for converting terephthalylidene dicamphor sulfonate represented by the following formula (2) into terephthalylidene dicamphor sulfonic acid represented by the following formula (1) in the presence of a cation exchange resin.

[Formula 1]

[Formula 2]

[In Formula 1 and 2,

M is an alkali metal or N (R ¹ ) (R ² ) (R ³ ) (R ⁴ ) and R ¹ to R ⁴ are independently of each other hydrogen or (C 1 -C 7) alkyl;

R is (C1-C7) alkyl or (C1-C7) alkoxy;

n is 0 or an integer of 1 to 4, and when n is 2 or more, R may be different or the same.]

The conversion method of the present invention can be converted almost entirely by using a cation exchange resin without using an inorganic acid or an organic acid, which is a conventional method, and a small amount of cation exchange resin compared to a method using an inorganic or organic acid, which is a conventional method. Is a very economical way of converting high conversion rates.

In addition, there is no need for a separate process for removing salts by easily removing salts generated as by-products.

Conventional methods for converting using known inorganic or organic acids have problems in that excess acid must be removed and salts corresponding to each acid produced as a by-product have been removed. In addition, the degree of acidification may vary depending on the type of acid used, and the conventional method of using a general acid greatly reduces the content of terephthalylidene dicamphor sulfonic acid.

On the other hand, the method of acidifying the terephthalylidene dicamphor sulfonate of the present invention and converting it to terephthalylidene dicamphor sulfonic acid does not require the use of excess acid by using a cation exchange resin, and requires a separate process for removing salts. In addition, since terephthalylidene dicamphor sulfonic acid is obtained in an aqueous solution, it can be prepared as a product which can be immediately distributed if the concentration of 33% is adjusted.

For example, a cation exchange resin is first charged to a column, and then passed through a terephthalylidene dicamphor sulfonate dissolved in water. Only a cation exchange resin corresponding to an equivalent ratio of much less than that of a general inorganic or organic acid is used. Almost all acidification occurs. In addition, salts generated as by-products are easily removed, and terephthalylidene dicamphor sulfonic acid is obtained as an aqueous solution, so that a product can be immediately distributed when the concentration is adjusted to 33%.

Therefore, the method for converting terephthalylidene dicamphor sulfonate of the present invention to terephthalylidene dicamphor sulfonic acid is a very efficient process with high conversion rate and purity.

The method for converting terephthalylidene dicamphor sulfonate to terephthalylidene dicamphor sulfonic acid using a cation exchange resin according to an embodiment of the present invention is carried out by adding a cation exchange resin to an aqueous solution of terephthalylidene dicamphor sulfonate to acidify it. However, it can be acidified by increasing the yield and simplifying the process, and economically, by filling the column with a cation exchange resin and then passing the aqueous solution of terephthalylidene dicamphor sulfonate.

The compounds represented by the formulas (1) and (2) described in the present invention include all of the isomers in cis-trans form for each double bond, and the like. Alkoxy ”includes both straight and pulverized forms and has 1 to 7 carbon atoms, preferably 1 to 5, more preferably 1 to 3 carbon atoms.

The alkali metal which is M according to an embodiment of the present invention may be any alkali metal in the range recognized by those skilled in the art, and examples thereof include Li, Na, K, and the like, and preferably Na in terms of reaction efficiency.

R according to an embodiment of the present invention may be (C1-C5) alkyl or (C1-C5) alkoxy, preferably (C1-C5) alkyl, and in the case where no substituent is present in phenylene The corresponding n may be zero.

The cation exchange resin according to an embodiment of the present invention combines a sulfonic acid group (-SO ₃ H) or a carboxyl group (-COOH) as an exchange group to the basic polymer matrix of the network structure, and Ca ²⁺ , Na ⁺ , H ^+. By exchanging a cation such as, it may be a strong acid cation exchange resin or weak acid cation exchange resin, preferably H-type cation exchange resin capable of exchanging cations of H ⁺ .

Specifically, the cation exchange resin according to an embodiment of the present invention may be a copolymer of divinylbenzene and styrene or a copolymer of divinylbenzene and acrylate or a tetrafluoroethylene polymer, and the exchange group may be sulfonic acid or carboxylic acid. It may be preferably a sulfonic acid, more preferably in terms of reaction efficiency may be a sulfonated styrene resin crosslinked with divinylbenzene.

Preferably, the cation exchange resin according to one embodiment of the present invention is a sulfonated styrene resin crosslinked with divinylbenzene as an H-type cation exchange resin, and has an ion exchange capacity of 1 meq / ml or more, preferably 1 to 1 3 meq / ml, more preferably 1.5 to 3 meq / ml.

The ion exchange capacity described in the present invention is measured in terms of the number of ions that can be exchanged and can be expressed in terms of polymer volume (Volume Capacity per volume), preferably wetted bed (wetted polymer) swelling Refers to milliquivalents of exchange capacity per volume.

Specifically, when the cation exchange resin is used to fill the column, the cation exchange resin may be used by filling an amount corresponding to a volume ratio of 2 to 6 times, or 1 to 3 times the weight ratio of the terephthalylidene dicamphor sulfonate. It can be regenerated and used repeatedly with dilute hydrochloric acid. The elution rate of the column can be passed 0.2 to 2 times the reaction liquid per hour relative to the volume of the cation exchange resin filled in the column.

The terephthalylidene dicamphor sulfonic acid solution eluted from the column can be concentrated to obtain terephthalylidene dicamphor sulfonic acid as a brown solid. In addition, some of the water in the aqueous solution of terephthalylidene dicamphor sulfonic acid eluted out can be distilled off, quantified by 0.1 mol potassium hydroxide, prepared in an aqueous solution of 33%, and prepared as a commercially available product.

Preferably, the conversion method of the present invention may use an aqueous solution of terephthalylidene dicamphor sulfonate dissolved in terephthalylidene dicamphor sulfonate represented by Formula 2, wherein the aqueous solution is terephthalylidene dicamphor sulfonate 100 It may be prepared by using 500 to 1000 parts by weight, preferably 700 to 1000 parts by weight of water.

Hereinafter, the present invention will be described in more detail with reference to the following examples, which are not intended to limit the present invention.

Example 1 Preparation of Terephthalylidene Dicamphor Sulfonic Acid

After dissolving 12 g (20 mmol) of disodium terephthalylidene decamper sulfonate in 100 ml of water, 200 ml (1.8 meq / ml) of cation exchange resin, trilite SCR-BH type (TRILITE SCR-BH; Samyang Corp.) Product) and stirred at room temperature for 5 hours. The resin was removed by filtration and washed with 50 ml of water. Water was distilled off under reduced pressure, and the resulting solid was dried under reduced pressure to obtain 10.4 g (yield = 93.4%) of brown solid terephthalylidene dicamphor sulfonic acid as a target compound.

1 g of this solid is precisely weighed, dissolved in 50 ml of water, and titrated with 0.1 mol of potassium hydroxide solution (indicator: 1 ml of phenolphthalein solution). In the same way and corrected by blank test, the content of terephthalylidene dicamphor sulfonic acid in the acidified solid was 89.7%.

Example 2 Preparation of Terephthalylidene Dicamphor Sulfonic Acid

The same procedure as in Example 1 was conducted except that 12.7 g of dipotassium terephthalylidene dicamphor sulfonate was used to obtain 10.5 g of the target compound, brown solid terephthalylidene dicamphor sulfonic acid. The terephthalylidene dicamphor sulfonic acid content of this solid was 89.6%.

Example 3 Preparation of Terephthalylidene Decamper Sulfonic Acid

Except having used 11.9 g of diammonium terephthalylidene dicamphor sulfonate, it carried out similarly to Example 1, and obtained 10.4g of brown solid terephthalylidene dicamphor sulfonic acid which is a target compound. The terephthalylidene dicamphor sulfonic acid content of this solid was 89.5%.

Example 4 Preparation of Terephthalylidene Decamper Sulfonic Acid

20 L (1.8 meq / ml) cation exchange resin, Trilite SCR-B-H (TRILITE SCR-BH; manufactured by Samyang Corp.) was charged to the column. 4 kg (6.6 mol) of disodium terephthalylidene decamper sulfonate dissolved in 28 L of water was eluted at a rate of 9 L / hr. After washing with 16 L of water, water was distilled off under reduced pressure from the reaction solution, and the resulting solid was depressurized and dried to obtain 3.6 kg (yield = 97%) of the title compound of brown solid terephthalylidene dicamphor sulfonic acid.

1 g of this solid was precisely weighed, dissolved in 50 ml of water, and titrated with 0.1 mol of potassium hydroxide solution (indicator: 1 ml of phenolphthalein solution). In the same way, the calibration was carried out in the same manner and the terephthalylidene decamper sulfonic acid content was 99.9%.

¹ H-NMR (CD ₃ OD) δ (ppm): 0.83 (s, 6H), 1.18 (s, 6H), 1.61 (m, 2H), 1.71 (m, 2H), 2.32 (m, 2H), 2.73 (m, 2H), 2.98 (d, 2H), 3.18 (m, 2H), 3.48 (d, 2H), 7.22 (s, 2H), 7.59 (s, 4H)

Example 5 Preparation of 33% Aqueous Solution of Terephthalylidene Dicamphor Sulfonic Acid

After carrying out as in Example 4, only two thirds of the water was removed from the resulting solution to obtain a 10.7 kg brown aqueous solution. Quantification was carried out as in Example 4 to obtain a 33% aqueous solution of terephthalylidene dicamphor sulfonic acid.

Comparative Example 1 Acidification Using Hydrochloric Acid

12 g (20 mmol) of disodium terephthalylidene decamper sulfonate was dissolved in 30 ml of water and 30 ml of concentrated hydrochloric acid (360 mmol). After refluxing for 1 hour, the resulting solid was concentrated by filtration and filtered. Washed with 6N hydrochloric acid, dried under reduced pressure at 80 ° C., and dried under reduced pressure at 100 ° C. to obtain 7.02 g of solid.

1 g of this solid was precisely weighed, dissolved in 50 ml of water, and titrated with 0.1 mol of potassium hydroxide solution (indicator: 1 ml of phenolphthalein solution). In the same method and corrected for the test, the content of terephthalylidene dicamphor sulfonic acid in the acid acidified with hydrochloric acid was 33.6%.

Comparative Example 2 Acidification Using Methanesulfonic Acid

6.06 g (10 mmol) of disodium terephthalylidene decamper sulfonate was dissolved in 50 ml of water, then 17.29 g (180 mmol) of methanesulphonic acid was added and stirred at room temperature for 2 hours. The reaction solution was concentrated and water was completely removed using a Dean-Stark apparatus using 100 ml of toluene. The resulting solid was filtered, washed with toluene, dried under reduced pressure at 80 ° C., and dried under reduced pressure at 100 ° C. to obtain 7.68 g of solid.

Given that sodium methanesulfonate was included and quantified as in Comparative Example 1, the content of terephthalylidene dicamphor sulfonic acid in the acid acidified with methanesulphonic acid was about 22.5%.

Comparative Example 3 Acidification Using Trifluoroacetic Acid

6.06 g (10 mmol) of disodium terephthalylidene dicamphor sulfonate was dissolved in 50 ml of water, and the same procedure as in Comparative Example 2 was performed except that 20.52 g (180 mmol) of trifluoroacetic acid was added. Solid was obtained.

In view of the fact that sodium trifluoroacetate was included, the content of terephthalylidene dicamphor sulfonic acid in the solid acid acidified with trifluoroacetic acid was about 7.5%.

Comparative Example 4 Acidification with Sulfuric Acid

6.06 g (10 mmol) of disodium terephthalylidene decamper sulfonate was dissolved in 50 ml of water, and the same procedure as in Comparative Example 2 was performed except that 8.82 g (90 mmol) of sulfuric acid was added. Got it.

Given that sodium sulfate was included, the content of terephthalylidene dicamphor sulfonic acid in the solid acid acidified with sulfuric acid was about 19.7% when quantified as in Comparative Example 1.

It can be seen that the conversion rate of the terephthalylidene dicamphor sulfonic acid prepared in Examples 1 to 4 is very high compared to Comparative Example 1, and furthermore, Examples 1 to 4 do not require a process for removing a separate salt. It is simpler than this and the purity is high.

In addition, Comparative Examples 2 to 4 can be seen that not only has a low conversion rate, but also a terephthalylidene dicamphor sulfonic acid containing salts corresponding to the respective organic and inorganic acids, and thus has a low purity and requires a separate process for removing the same.

In conclusion, the method of converting terephthalylidene dicamphor sulfonate to terephthalylidene dicamphor sulfonic acid in the presence of the cation exchange resin of the present invention is not only a method having high conversion and purity compared to the conventional method, but also a simple conversion process. It is an economical and efficient way.

Claims (6)

A method for converting terephthalylidene dicamphor sulfonate represented by the following formula (2) into terephthalylidene dicamphor sulfonic acid represented by the following formula (1) in the presence of sulfonated styrene-based cation exchange resin crosslinked with divinylbenzene.
[Formula 1]

[Formula 2]

[In Formula 1 and 2,
M is an alkali metal or N (R ¹ ) (R ² ) (R ³ ) (R ⁴ ) and R ¹ to R ⁴ are independently of each other hydrogen or (C 1 -C 7) alkyl;
R is (C1-C7) alkyl or (C1-C7) alkoxy;
n is 0 or an integer of 1 to 4, and when n is 2 or more, R may be different or the same.] The method of claim 1,
M is Na and n is 0. delete delete The method of claim 1,
Wherein the cation exchange resin has an ion exchange capacity of 1 to 3 meq / ml. The method of claim 1,
The method is characterized by using an aqueous solution of terephthalylidene dicamphor sulfonate dissolved in terephthalylidene dicamphor sulfonate represented by the formula (2) in water.