JPS63284148A - Production of quaternary ammonium inorganic acid salt - Google Patents

Abstract

PURPOSE:To obtain the titled compound useful as a phase-transfer catalyst, etc., in high efficiency and purity in two steps, by reacting a tertiary amine with a carbonic acid diester and reacting the resultant quaternary ammonium carbonate with an inorganic acid while discharging produced CO2 gas from the system. CONSTITUTION:A tertiary amine of formula I (R1-R3 are hydrocarbon residue of tertiary amine) e.g. triethylamine is made to react with a carbonic acid diester of formula II such as dimethyl carbonate in a solvent such as methanol or in the absence of solvent at 20-200 deg.C. The resultant quaternary ammonium carbonate of formula III, etc., is made to react with an inorganic acid of formula HX (X is conjugated residue of inorganic acid) in a solvent or in the absence of solvent while removing the generated CO2 gas from the system under reduced pressure or by blasting an inert gas into the reaction system. If necessary, the reaction product is purified e.g. by recrystallization using a proper solvent to obtain the objective compound of formula IV, etc., having solid phase and high purity and useful as an electrolyte for aqueous or organic electrolytic solution, various additives, chemicals, etc.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention involves reacting a tertiary amine with a carbonic acid diester to obtain a corresponding quaternary ammonium carbonate, which is then mixed with an inorganic acid to decarboxylate it. The present invention relates to a method for producing a quaternary ammonium inorganic acid salt.

The quaternary ammonium inorganic acid salt obtained by the method of the present invention is
It is a useful organic compound that is used in a wide range of fields as various catalysts such as phase transfer catalysts, electrolytes for aqueous and organic electrolytes, various additives, and chemicals.

C. Prior Art] As a method for synthesizing quaternary ammonium salts, a method is generally employed in which tertiary amines are quaternized with an alkyl halide, dialkyl sulfate, etc. under heating. In addition, when producing quaternary ammonium salts with various anion species, a method using anion exchange of quaternary ammonium halides (chloride, bromide, iodide) is usually adopted. According to the reaction formula shown below, quaternary ammonium bromide is converted to quaternary ammonium hydroxide (reaction 1a), and then neutralized with an inorganic acid (reaction 1b), the quaternary ammonium bromide is reacted with an inorganic acid. method (reaction 2), in which quaternary ammonium bromide and an alkali metal salt of an inorganic acid are reacted, and an inorganic acid salt is obtained by precipitation or extraction. Method (Reaction 3), and a method of reacting quaternary ammonium bromide with a silver salt of an inorganic acid to precipitate bromide rays to obtain the desired product from the solution (Reaction 4)
), etc. can be exemplified.

R4NeOHe−+ R4NeOH”
(Reaction 1a) R4N"O8e+HΦA"-+R4N@A
”+IhO (reaction 1b) R4NqDBre+H@Ae-
+R,N@Ae↓+HBr (Reaction 2) R,NΦBr
e+Na'AeRJ@Ae+NaBr (Reaction 3) R
n, NeDBre+AgeAe-+Ra, NeAe+A
gBr↓ (Reaction 4) Methods for producing quaternary ammonium hydroxide by reaction 1a include a method in which quaternary ammonium bromide dissolved in a suitable solvent is reacted with a quaternary ammonium hydroxide type ion exchange resin; A method of reacting class ammonium bromide with an alkali metal hydroxide in a liquid medium, a method of separating bromide ions into Br by an electrochemical method to obtain a hydroxide, and a method of using a silver compound are known. It is being

[Problem that the invention seeks to solve]

However, any method using Reaction 1a is an expensive method for producing quaternary ammonium hydroxide, and it is generally difficult to completely remove the bromide ions in quaternary ammonium hydroxide, so Reaction 1b is used. This often causes problems with the purity of the neutralized product, and in the methods of Reactions 2 and 3, it is quite difficult to remove bromide ions from the target quaternary ammonium inorganic acid salts. This method is unsuitable as a production method for obtaining grade ammonium inorganic acid salts. Although the method based on Reaction 4 is considered to be preferable as a method for carrying out a quantitative reaction, the silver salt of an inorganic acid used as a raw material is extremely expensive, and it is difficult to say that it is a method that can be adopted industrially.

The above description uses quaternary ammonium bromide as an example, but the same is true when using other halides, sulfates, etc., and there are generally no known methods for producing various anion-exchanged salts efficiently and with high purity. Not yet.

[Means for solving problems]

The present inventors have established a new technology for an industrial manufacturing method that enables more efficient production than conventional methods and improves the purity of the desired product, and has thus arrived at the present invention.

That is, the present invention provides a method for producing an inorganic acid salt of quaternary ammonium, (a process step for producing a corresponding quaternary ammonium carbonate by reacting an al tertiary amine with a carbonic acid diester), which further comprises: The quaternary ammonium inorganic acid salt is characterized in that it undergoes a two-step process of mixing a quaternary ammonium carbonate with an inorganic acid and removing carbon dioxide gas from the system to produce the corresponding inorganic acid salt. This paper proposes a method for manufacturing.

[Detailed description of the invention]

Tertiary amines that can be used as raw materials for the present invention include trimethylamine, triethylamine, ethyldimethylamine, tri-n-propylamine, tri-n-butylamine, tri-n-octylamine, diethyl-1-propylamine, N, N, N' , aliphatic amines such as N'-tetramethylethylenediamine, N-methylpyrrolidine,
N-ethylpyrrolidine, N-methylpiperidine, N-ethylpiperidine, N-n-butylpiperidine, N-methylhexamethyleneimine, N-ethylhexamethyleneimine, N-methylmorpholine, N-butylmorpholine,
N,N'-dimethylpiperazine, N,N'-diethylpiperazine, 1,5-diazabicyclo(4,3°0)-
5-Nonene, 1,8-diazabicyclo(5,4゜0〕-
Alicyclic amines such as 7-undecene, pyridine, 4-
Dimethylaminopyridine, picolines, N-methylimidazole, N-methylbenzimidazole, quinoline,
Examples include nitrogen-containing heterocyclic aromatics such as 4.4'-dipyridyl.

Examples of diester carbonates include dimethyl carbonate, ethylmethyl carbonate, diethyl carbonate, dipropyl carbonate, etc., but it is preferred that the alkyl group has fewer carbon atoms, such as dimethyl carbonate, because the quaternization reaction proceeds more quickly.

There are no particular restrictions on the inorganic acid, but the stronger the acid compared to carbonic acid, the faster the exchange into anions will be completed. Furthermore, anion exchange can be achieved even with an acid weaker than carbonic acid if it is carried out while gradually shifting the equilibrium and takes time. Specific examples of these inorganic acids include liverr HCL HBr+
Old, HNO31HzSO<.

H+PO+, HJOa, HC104, HBFI H
PF6. HSbFa.

HASF,,,HOS02G/,HOSOzF
IHzCrOa, HzStOb*)IMnO4+ HR
Examples include eOa, HzSeOa+ H5CN, and the like.

In the first step, the quaternization reaction, the molar ratio of tertiary amine and diester carbonate is 0.2 to 5, more preferably 0.3 to 3.
and in the presence or absence of a solvent, the reaction temperature is 20-20
It is carried out at 0°C, more preferably at 30-160°C. Usually, once the tertiary amine has been sufficiently converted to the quaternized product, the unreacted amine or diester carbonate is distilled off together with the solvent if a solvent is used, or if necessary, recrystallized from an appropriate organic solvent. Then, it is sent to the second process.

In the second step, usually, a stoichiometric value or a small excess amount of inorganic acid is added dropwise to the quaternary ammonium carbonate in the presence or absence of a solvent, and the generated carbon dioxide is removed under reduced pressure or an inert gas is introduced into the reaction system. Remove by blowing.

At this time, the reaction that occurs is expressed by the following formula when dimethyl carbonate is used as the raw material.

(First step) R+RzR3N + MezCO3−
R+RJJeN@0C-OMe (2nd process) R+Rz
R3MeN"C-OMe + HX-RIR2R3Me
N'Y'+ MeOH+ COz t (wherein, RIR1R3 is a hydrocarbon residue of a tertiary amine,
represents the conjugate base of the inorganic acid.) After the reaction, the by-product alcohol and the solvent are distilled off when the solvent is used, and the solid obtained is the target quaternary ammonium inorganic acid salt. If necessary, a highly pure product can be obtained by recrystallization using an appropriate solvent.

Further, when an inorganic acid is used in an amount slightly in excess of the stoichiometric value in order to completely remove carbonate ions, the excess inorganic acid can be removed by a treatment such as recrystallization.

〔Effect of the invention〕

According to the method of the present invention, it is possible to efficiently produce various quaternary ammonium inorganic acid salts, and at the same time, a major feature of the present invention is that the desired salt can be obtained with high purity. be.

〔Example〕

Hereinafter, the present invention will be explained in more detail with reference to Examples.

Example-1 (1st step) A stirring autoclave was filled with 17.8 g of dimethyl carbonate, 20.0 g of triethylamine, and 20.0 g of methanol as a solvent, and the reaction temperature was 115°C and the reaction pressure was 5.
．． The reaction was carried out at 0 kg/cJG for 12 hours. After the reaction, the autoclave was cooled and the reaction solution was taken out and analyzed by gas chromatography, and the conversion rate of triethylamine was 94.
．． 6%, and the solid yield after distilling off unreacted substances and solvent was 34.0 g (89.9% of the theoretical value).
This product was confirmed to be triethylmethylammonium methyl carbonate by elemental analysis and H-NMR.

(Second step) 10.0 g of the obtained triethylmethylammonium methyl carbonate was dissolved in 15 g of water, and 60% HCI
8.8 g of t Oe aqueous solution was gradually added. At the same time as the addition, carbon dioxide gas was generated violently. Degas at 40°C/20 mHg for 2 hours to remove carbon dioxide gas more completely.
Carbonate ions are 20pp by ion chromatography.
After confirming that the water was below m, water was distilled off. 9. Residue.
Recrystallization from 5 g of EtOH gave 10.4 g of triethylmethylammonium perchlorate (82.7% yield based on triethylamine).

Example-2 (1st step) 68.8 g of dimethyl carbonate in a stirred autoclave.

Filled with 65.0 g of N-methylpyrrolidine and 60.0 g of methanol as a solvent, the autoclave was reacted for 6 hours at a reaction temperature of 120°C and a reaction pressure of 3 kg/dG. After the reaction, the autoclave was cooled, and the reaction solution was taken out and subjected to gas chromatography. When analyzed by tograph, the conversion rate of N-methylpyrrolidine was 98.1%. When unreacted substances and solvent were distilled off at 130°, 6 g of solid was recovered (theoretical value of 97
．． 6%), elemental analysis and H-NMR, it was confirmed that this solid was N,N-dimethylpyrrolidinium methyl carbonate.

(Second step) 10.0 g of the obtained N,N-dimethylpyrrolidinium methyl carbonate and 12.9 g of 42% HBF4 aqueous solution
Highly purified dimethylpyrrolidinium tetrafluoroborate 1 was prepared in the same manner as in Example 1 (second step) except that
0.1 g (92.4% yield based on N-methylpyrrolidine) was obtained.

Example 3 5.7 g of 15O3F was gradually added to 10.0 g of N,N-dimethylpyrrolidinium methyl carbonate obtained in Example 2 (first step) under a dry nitrogen atmosphere, and heated at 50°C for 15 minutes. Carbon dioxide gas was removed with Hg to obtain 10.8 g of dimethylpyrrolidinium fluorosulfate (92.7% yield based on N-methylpyrrolidine).

Example-4 (1st step) 8.8 g of dimethyl carbonate and 10.0 g of lysine as raw materials
5 The same reaction as in Example 1 was carried out except that 10.0 g of methanol was used as the solvent, and 16.8 g of solid was obtained (78.5% of the theoretical yield). Elemental analysis, H-NM
It was confirmed from R etc. that this solid was N-methylpyridinium methyl carbonate.

(Second step) N-methylpyridinium methyl carbonate 10,0
The same operation as in Example 1 was performed except that 1099.9 g of 60% HC was used to obtain 10.8 g of N-methylpyridinium perchlorate (74.3% yield based on pyridine).

Example-5 (1st step) 17.0 g of dimethyl carbonate and 10.0 g of 1.5-diazabicyclo(4,3,0)-5-nonene as raw materials. The same reaction as in Example 1 was carried out except that Og was used.1
Obtained 2.6 g of viscous liquid (theoretical yield 72.8%)
From elemental analysis, 'H-NMR, MS, etc., this viscous liquid was found to be 1-methyl-1-azonia-5-azabicyclo (4
,3,0)-5-nonene methyl carbonate.

(Second step) 1-methyl-1-azonia-5-azabicyclo(4,3
,0) -5-nonene methyl carbonate 8.0g and 4
The same operation as in Example 1 was performed except that 47.4 g of 0% HBF was used to obtain 8.2 g of 1-methyl-1-azonia-5-azabicyclo(4,3,0)-5-nonenetetrafluoroborate. (1,5-diazabicyclo(4,3
, 0) -70.8% yield based on -5-nonene).

Claims (1)

[Scope of Claims] A method for producing a quaternary ammonium inorganic acid salt, comprising: (a) a step of producing a corresponding quaternary ammonium carbonate by reacting a tertiary amine with a carbonic acid diester; (b) a step of producing a quaternary ammonium carbonate produced; A method for producing a quaternary ammonium inorganic acid salt, comprising a two-step process of mixing a salt with an inorganic acid and removing carbon dioxide from the system to produce a corresponding inorganic acid salt.