PL164525B1 - Method of obataining 2-aminoalkanosulfonic acids - Google Patents

Abstract

1. Process for producing 2-amino alkane sulfonic acids by reaction of dichloroalkane with anhydrous sodium sulphate, next with ammonolysis, characterised in that, the reaction between dichloroalkane and anhydrous sodium sulphate is conducted in the aprotic solvent in temperature between 40 to 140 degrees C, and pressure 0.98 x 10<5> - 29.4 x 10<5> Pa in anhydrous sodium sulphate excess, in the presence of a catalyst and following extraction of sodium salt of 2- chloro alkane sulfonic acid, the salt is converted into 2- chloro alkane sulfonic acid during the ammonolysis reaction applying aqueous solutions of ammonia with concentration of 25 to 50% by weight, in temperature of 80 to 170 degrees C, in molar excess of ammonia, 2-amino alkane sulfonic acid is extracted from the post reaction mixture on conclusion of the ammonolysis, applying stoichiometric quantity of mineral acid.

Description

The subject of the invention is a process for the preparation of 2-aminoalkanesulfonic acids, used in the synthesis of drugs, organic compounds for biochemical research or biologically active compounds.

The method of J. W. Schick, Industrial and Ingineering Chemistry, 39, 906 (1947) is known, involving the reaction of anhydrous sodium sulfite with 1,2-dichloroethane in a copper reactor. During the reaction, large amounts of waste water were generated, containing unreacted sodium sulfite, sodium chloride, intermediates and copper salts as a catalyst. The isolation and crystallization of the sodium salt of 2-chloroalkanesulfonic acid did not allow the recovery of unreacted sodium sulfite in anhydrous form.

After isolation and purification of the sodium salt of 2-chloroethanesulfonic acid, the ammonolysis of the salt was carried out with anhydrous or aqueous ammonia solutions in the presence of a copper salt. The process of isolating the product made it impossible to reuse the expensive catalyst. Due to side reactions, the resulting product was colored. It was necessary to purify it, e.g. by crystallization.

In the methods mentioned, expensive cuprous salts were used as catalysts, which were irretrievably lost; anhydrous sodium sulfite was likewise lost. For these reasons, the methods were uneconomical and the process itself was very long, reaching 80 hours.

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The aim of the invention was to develop a simple and economical method of producing 2-aminoalkanesulfonic acid, which does not generate large amounts of waste water.

Surprisingly, it turned out that the process of producing 2-aminoalkanesylphonic acid can be significantly simplified and, in place of expensive starting materials, readily available waste dichloroalkanes can be used.

The process according to the invention consists in reacting a dichloroalkane with anhydrous sodium sulphite in an aprotic solvent at a temperature of 40 to 140 ° C, a pressure of 1 to 30 atm in excess anhydrous sodium sulphite in the presence of a catalyst.

The process leading to the preparation of sodium salt of 2-chloroalkanesulfonic acid takes place in an aprotic solvent and in the presence of an anhydrous catalyst, which may be sodium or potassium bromides and iodides. The dichloroalkane and solvent are stripped from the resulting mixture, and unreacted, anhydrous sodium sulfite is isolated. This operation of the process leaves the 2-chloroalkanesulfonic acid sodium salt in the reactor and causes no waste water.

After preparation of the sodium salt of 2-chloroalkanesulfonic acid by ammonolysis, the given salt is converted into 2-aminoalkanesulfonic acid. The reaction takes place in an excess of ammonia used in 25 to 50% by weight aqueous solutions at 80 to 170 ° C. After completion of ammonolysis, the 2-aminoalkanesulfonic acid is separated from the reaction mixture with a stoichiometric amount of mineral acid.

After isolation of the 2-aminoalkanesulfonic acid with mineral acid, the unreacted 2-chloroalkanesulfonic acid sodium salt, catalyst, ammonia and ammonium salts such as sulfate or ammonium chloride return back to ammonolysis. There is little waste water in ammonolysis.

Preferably, acetone or methyl ethyl ketone is used as the aprotic solvent.

Preferably, potassium iodide and / or sodium bromide and / or potassium bromide are used as catalyst.

Favorable results are obtained when the process is carried out with an amount of emulsifier up to 1% by weight.

Preferably, the ammonolysis is carried out after the anhydrous sodium sulfite has been separated from the reaction mixture. Preferably, the ammonolysis is carried out with a mixture of aqueous solutions of ammonia and ammonium chloride and / or ammonia and ammonium sulphate in excess of ammonia.

The 2-aminoalkanesulfonic acid according to the invention is obtained in a continuous manner. 2-aminoalkanesulfonic acid is separated from the reaction mixture with the mineral acid, the remainder of the mixture is recycled to the ammonolysis process.

The advantage of the method according to the invention is the several times reduction of its duration.

In the process according to the invention, the raw material and catalyst are fully utilized. The amount of wastewater is minimized.

2-aminoalkanesulfonic acid is obtained without prior isolation and without crystallization of the sodium salt of 2-chloroalkanesulfonic acid.

In the method, the efficiency is more than doubled. In the methods known so far, the total yield did not exceed 40%. In the method according to the invention, the yield is up to 85 to 96%. The obtained 2-aminoalkanesulfonic acid is characterized by high purity, up to 99%.

The method according to the invention enables the utilization of harmful organochlorine waste.

The solution according to the invention is illustrated in the following examples.

Example 1 9.8 g (0.1 mol) of 1,2-dichloroethane, 25.2 g (0.2 mol) of sodium sulphite, 2 g of potassium bromide, 50 g of acetone, 0.5 g (0.1 moles) are placed in an autoclave equipped with a stirrer, thermometer and manometer. g of castor oil. The listed ingredients are mixed and heated to 100 ° C under a pressure of 7.8 10 ⁵ Pa for 5 hours. After the reaction has ended, the solvent and unreacted 1'-dichloroethane are stripped off and anhydrous sodium sulfite is isolated. Subsequently, 34 g of 25 rosethe ammonia water are introduced into the autoclave and heated for 4.5 hours at 110 ° C. The yield of 2-aminoetaeaulfonic acid is 86%.

Example II. 9.8 g (0.1 mol) 1,2-dichloroacetate, 37.8 g (0.30 mol) sodium sulfite, 3 g sodium bromide, 60 g acetone, 0.5 g castor oil are mixed and heated to the temperature

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115 ° C, under a pressure of 12.7 10 ⁵ Pa for 6.5 hours. Upon completion of the reaction, the solvent is stripped off and anhydrous sodium sulfite is isolated. Subsequently, 21 g of 25% ammonia water were introduced into the autoclave and the mixture was heated at 140 ° C for 2 hours. Product yield 89%.

Example III. 14.7 g (0.15 mole) 1,2-dichloroethane, 31.5 g (0.25 mole) sodium sulphite, 1.5 potassium iodide, 50 g methyl ethyl ketoneU and 0.5 ę οΖ ^ 5 yicin rosin ζΪ5 and heated at 130 ° C for 2.5 hours. After stripping the unreacted 1,2-dichloroethane and solvent, 22 g of 35% ammonia water was added to the residue and heated at 155 ° C for 1.5 hours. Product yield 96%.

Example IV. 17.0 g (0.15 mol) 1,2-dichloropropane, 44.1 g (0.35 mol) sodium sulfite, 1.5 g potassium iodide ę 60 g methyl ethyl ketone and 1 g of stearic acid are sprayed and heated at 125 ° C with time 6 hours. After stripping the unreacted 1,2-dichloropropae and the solvent, 51 g of 25% ammonia water are added to the residue, heated to 150 ° C for 2 hours. The yield of 2-aminopropanesulfonic acid is 88%.

Depaitament Wydawnictwa UP RP. Circulation of 90 copies

Price: PLN 10,000

Claims (7)

Patent claims 1. The method of producing 2-aminoalkanesulfonic acids by reacting a dichloroalkane with anhydrous sodium sulfite followed by ammonolysis, characterized in that the reaction between dichloroalkane and anhydrous sodium sulfite is carried out in an aportonic solvent at a temperature of 40 to 140 ° C, pressure 0.98 -10 ⁵ -29.4-10 ⁵ Pa in excess of anhydrous sodium sulphite, in the presence of a catalyst and after obtaining the sodium salt of 2-chloroalkanesulphonic acid, this salt is converted by ammonolysis to 2-chloroalkanesulphonic acid with 25 to 50% by weight aqueous ammonia solutions , at a temperature of 80 to 170 ° C, in a molar excess of ammonia, and after completion of the ammonolysis reaction, the 2-aminoalkanesulfonic acid is separated from the reaction mixture with a stoichiometric amount of mineral acid. 2. The method according to p. The process of claim 1, wherein the aprotic solvent is acetone or methyl ethyl ketone. 3. The method according to p. The process of claim 1, wherein the catalyst is potassium iodide and / or sodium bromide and / or potassium bromide. 4. The method according to p. The process of claim 1, characterized in that the reaction between anhydrous sodium sulfite and dichloroalkane and ammonolysis is carried out in the presence of an emulsifier in an amount of up to 1% by weight. 5. The method according to p. The process of claim 1, characterized in that the ammonolysis is carried out after the separation of anhydrous sodium sulfite from the reaction mixture. 6. The method according to p. The process of claim 1, characterized in that the ammonolysis is carried out with a mixture of aqueous solutions of ammonia and ammonium chloride and / or ammonia and ammonium sulfate in excess of ammonia. 7. The method according to p. The process of claim 1, wherein the reaction for the preparation of 2-aminoalkanesulfonic acid is carried out continuously with the isolation of the product and recycling of the remainder of the reaction mixture to the ammonolysis.