DD225691A1 - METHOD FOR THE PREPARATION OF PURE QUATERNAER ALKYL-ALKANOL AMMONIUM COMPOUNDS - Google Patents

Abstract

The aim of the invention is to completely separate the glycol and unreacted amine obtained in the quaternization of amines with alkylene oxides, and with little effort. It can be from the corresponding solutions using acetone triethyl-monoethanol-ammonium hydrogen carbonate (CH3CH2CH2) 3 (HOCH2) N HCO3 and triethyl-monoisopropanol-ammonium hydrogen carbonate (CH3CH2) 3 (CH3CH (OH) CH2) N HCO3 crystalline and free of by-products , From these and analogous substances, the free hydroxides and their salts can be obtained. The substances are suitable for applications where the absence of impurities, especially glycol, is required. Fig. 2

Description

field of use

The pure quaternary alkyl-alkanol-ammonium compounds are for direct application and further processing in chemistry and pharmacy particularly in those cases in which the absence of foreign components, in particular of glycol, is to be claimed.

Characteristic of the known technical solutions

In the quaternization of amines with alkylene oxides, even in the presence of carbon dioxide, in many cases (for example when using triethylamine and ethylene oxide or propylene oxide), the corresponding glycols are inevitably formed as by-products, such as with the aid of the ^{I 3} C NMR method. Spectroscopy can be detected. The substances presented according to DRP 655882 from 9.8.1931 also contain considerable amounts of glycol, which, however, could not be determined analytically by the authors due to a lack of technical possibilities.

Since both glycol and the alkyl-alkanol-ammonium hydrogencarbonates are readily water-soluble and the glycol can not be removed by distillation from the quaternary alkylalkanol-ammonium hydrogencarbonate solutions, previously glycol-free products were not readily accessible.

Object of the invention

The aim of the invention is to find an economically favorable process for the preparation of glycol-free, quaternary alkyl alkanolammonium compounds.

Explanation of the essence of the invention

Object of the invention is; it is in the synthesis of quaternary alkyl-alkanol-ammonium compounds from amines and alkylene oxides still completely separated by-products such as glycols and glycol ethers with little effort completely separate.

According to the invention, the object is achieved in that glycols in acetone, however, are slightly soluble, quaternary alkyl alkanolammoniumhydrogencarbonate not soluble. It is possible to isolate the latter in crystalline form and then to wash the resulting crystals with an organic solvent, suitably with acetone, so as to obtain very pure crystalline quaternary alkyl alkanol-ammonium hydrogencarbonates. From these, secondary products, for. As the free quaternary bases or their salts can be obtained.

To illustrate the crystalline alkyl-alkanol-ammonium carbonates of the general formula NR ₄ - _n R ' _n HCO ₃ xH ₂ O (n = 1 to 4, R = alkyl or cycloalkyl group, R' = hydroxyalkyl group), two variants were developed.

First, it is possible, the solution obtained after reacting the amine with carbon dioxide and alkylene oxide in an aqueous medium in vacuo, expediently at elevated temperature, so narrow that after addition of acetone crystallization occurs.

At the same time, the majority of glycol is dissolved in the acetone. Small, the crystals with the mother liquor still adhering amounts of glycol can be easily filtered after filtering off the crystals with an organic solvent, conveniently with acetone.

In the second variant, equimolar amounts of armin, alkylene oxide, carbon dioxide and water are converted directly into acetone. The formed glycol is taken up by the acetone, and the crystallization of the quaternary alkyl-alkanol

Ammonium hydrogen carbonate then takes place directly in the reaction solution, so d ^ ß_ejn_Aufkonzentriefen deleted. The

Crystals can be easily separated and freed from glycol still adhering by washing with acetone. It is possible to work at room temperature. Unreacted starting materials (carbon dioxide and alkylene oxide)

can be used again in the circulation. The reaction can also be carried out at elevated pressure u ~ d / or elevated temperature (up to 100 ⁰ C) in an autoclave.

The advantage of the invention is that impurity-free quaternary alkyl-2-hydroxy-alkyl-ammonium compounds are made accessible in a simple and economically favorable manner.

embodiments example 1

In a mixture of 101 g of triethylamine and 330 cm ^{3 of} water is introduced while stirring carbon dioxide until all the triethylamine has gone into solution, that is, the mixture is homogeneous. It is then heated to 70 ⁰ C. At this temperature, 58 g of propylene oxide are introduced in gaseous form with stirring. The gas flow must be regulated so that the propylene oxide is completely absorbed by the liquid. The reaction vessel is allowed to stand for 8 hours, then heated again to 7O ⁰ C and allowed to cool. This reaction mixture is concentrated in vacuo at about 2.7 kPa and a temperature of 8O ⁰ C to a content of Triethylmonoisopropanolammoniumhydrogencarbonat of about 80Ma .-%.

After cooling to 25 ° C, it is mixed with 150cm ^{3 of} acetone and thereby brought to crystallization. The crystals are washed 4 times with 150 cm ^{3 of} acetone and then dried at 40 ⁰ C in a vacuum.

This gives colorless, well-crystallized triethyl monoisopropanol-ammonium hydrogen carbonate with an X-ray diffraction diagram (Co-K _a radiation) given in FIG. 1. The melting point is 133-135 ° C. The ¹³ C-NMR spectrum of a concentrated aqueous solution (Figure 2) has only signals attributable to the triethyl monoisopropanolammonium ion, while the reaction mixture prior to crystallization according to ¹³ C-NMR spectrum (Figure 3) contaminated with propylene glycol is.

Example 2

As described in Example 1, by introducing carbon dioxide into a mixture of water and triethylamine, a triethylammonium bicarbonate solution is first prepared. In this one initiates at 60 ⁰ C 44g gaseous ethylene oxide.

Stir vigorously and regulate the gas flow so that the ethylene oxide is completely absorbed by the liquid. After introduction, the reaction vessel is allowed to stand for 8 hours, heated again to 6O ⁰ C, allowed to cool and performs the crystallization and purification, as described in Example 1 by.

The Triethylmonoethanol-ammonium hydrogencarbonate is also obtained as a colorless, well-crystallized sub-dance. The melting point is 119-121 ⁰ C.

The ¹³ C-NMR spectrum of a concentrated aqueous solution (Figure 4) shows only signals attributable to triethylmonoethanol-ammonium-lon. The reaction mixture before crystallization, on the other hand, is contaminated with ethylene glycol, as shown in the ¹³ C NMR spectrum (Fig.5).

Example 3

101 g of triethylamine and 14 cm ^{3 of} water are dissolved in 600 cm ^{3 of} acetone. Into this solution is introduced at room temperature with stirring, a mixture of 58 g of gaseous propylene oxide and about three times the amount of carbon dioxide within about 90 minutes. After a few hours, triethyl monoisopropanol-ammonium bicarbonate precipitates in the form of large colorless crystals which are easily filtered off and washed with a little acetone (melting point and purity as indicated in Example 1).

Example 4

101 g of triethylamine, 44 g of dry ice, 58 g of propylene oxide, 12 cm ^{3 of} water are heated to 90 ^° C. in an autoclave together with 400 cm ^{3 of} acetone for 4 days. The triethyl monoisopropanol-ammonium bicarbonate precipitates in crystalline form (melting point and purity as indicated in Example 1).

Example 5

332 g of pure crystalline triethyl monoisopropanol-ammonium hydrogen carbonate (prepared according to Example 1, 3 or 4) are dissolved in 1 dm ^{3 of} water. With stirring and cooling, 180 g of calcium hydroxide are added and allowed to react at 25 ° C for about 5 hours.

Then filtered and washed the filter cake with about 100cm ^{3 of} water. The filtrate, gives an aqueous solution of triethyl-monoisopropanol ammonium hydroxide, (less than 2.3 10 ^-2 mol / dm ^3), but no impurities having a small quantity of calcium ions with the aid of ¹³ C-NMR Spectroscopy can be detected (same spectrum, as shown in Fig. 2).

Example 6

332 g of pure crystalline triethyl monoisopropanol-ammonium hydrogen carbonate (prepared according to Example 1, 3 or 4) are dissolved in 1 dm ^{3 of} water. With stirring and cooling, 257 g of barium hydroxide are added and allowed to react at 25 ⁰ C for about 2 hours.

The aqueous triethyl monoisopropanol-ammonium hydroxide solution is obtained as described in Example 5. It is contaminated with a maximum of 1.1 × 10 ^-3 mol / dm ³ barium ions. This gives a ¹³ C-NMR spectrum which is identical to that which gives the product obtained in Example 5.

Example 7

In a 2 molar aqueous solution of an acid, for. For example, hydrochloric acid, as much quaternary alkyl alkanolammoniumhydrogencarbonat registered until, after the escape of carbon dioxide liberated in the reaction, a neutral solution of the corresponding salt is formed, which can be concentrated if necessary in vacuo.

Claims (7)

Invention claims: 1. A process for preparing pure, quaternary alkylalkanol-ammonium compounds, characterized in that from the reaction mixture formed by the reaction of amines with alkylene oxides in the presence of water and carbon dioxide reaction mixture first quaternary alkylalkanol-ammonium hydrogencarbonates of the general formula NR ₄ _ _n R ' _n HCO ₃ · xH ₂ O (n = 1 to 4, R = alkyl or cycloalkyl group, R '= 2-hydroxyalkyl group) deposited in pure, crystalline form in the presence of acetone, washed with an organic solvent, dried and then optionally by reaction with bases which form sparingly soluble carbonates, be converted to quaternary alkyl-alkanol-ammonium hydroxides or by addition of acids to the corresponding alkyl-alkanol-ammonium salt solutions. 2. The method according to item 1, characterized in that after the reaction of aqueous amine solution with alkylene oxide in the presence of carbon dioxide resulting mixture in vacuo, preferably at elevated temperature, concentrated and then by addition of acetone and cooling the quaternary alkyl-alkanol-ammonium hydrogen carbonate is crystallized. 3. The method according to item 1, characterized in that the crystallization of quaternary alkyl alkanolammoniumhydrogencarbonaten is achieved by the reaction of amines with alkylene oxides is carried out in the presence of carbon dioxide in an aqueous acetone solution. 4. The method according to item 3, characterized in that the reaction temperatures are between 20 and 100 ⁰ C, being operated at temperatures above the boiling point of the solvent in a closed vessel under autogenous pressure and the reaction time is between 4 and 150 hours. 5. The method according to item 1 to 4, characterized in that the impurities contained in the crystallized quaternary alkyl alkanolammoniumhydrogen-carbonate crystals by adhering mother liquor by washing with a suitable organic solvent, preferably acetone, are removed. 6. The method according to item 1, characterized in that pure quaternary alkyl-alkanol-ammoniumhydroxidiösungen be prepared by dissolving the crystalline quaternary alkyl alkanolammoniumhydrogencarbonate in water and by reaction with sparingly soluble carbonates forming hydroxides or oxides, in particular alkaline earth metal hydroxides or oxides. 7. The method according to item 1, characterized in that the corresponding impurity-free salt solutions are prepared by reacting the pure crystalline quaternary alkyl alkanolammoniumhydrogencarbonate with aqueous acid solutions. For this 3 pages drawings