EP1786780A1

EP1786780A1 - Imidazolium-methyl sulfites for use as starting compounds for producing ionic liquids

Info

Publication number: EP1786780A1
Application number: EP05771331A
Authority: EP
Inventors: Laszlo Szarvas; Klemens Massonne
Original assignee: BASF SE
Current assignee: BASF SE
Priority date: 2004-08-24
Filing date: 2005-08-03
Publication date: 2007-05-23
Also published as: CN101006062A; WO2006021303A1; US20070255064A1; KR20070054216A; JP2008510741A

Abstract

The invention relates to the imidazolium-methyl sulfites of general formula (I), wherein the groups have the following independent meanings: R<sup

Description

IMIDAZOLIUM-METHYLSULFITE AS STARTING COMPOUNDS FOR THE MANUFACTURE OF IONIC LIQUIDS

description

5 The present invention relates to imidazolium methylsulfites of the general formula (I)

in which the radicals independently of one another have the following meaning: 0

R ¹ to R ³ :

Hydrogen, halogen, hydroxy, amino, aminocarbonyl, sulfo, cyano, nitro;

C ₁ to C ₂₀ alkyl, C ₂ to C ₂₀ alkenyl, C ₂ to C ₂₀ alkynyl, C ₁ to C ₂₀ alkyloxy, C ₂ to C ₂₀ alkenyloxy, C ₂ to C ₂₀ -alkynyloxy, C ₁ - to C ₂₀ -alkylcarbonyl, C ₁ - to C ₂₀ -

Alkyloxycarbonyl, C ₁ - to C ₂ o-acyloxy, C ₁ - to C ₂₀ -alkylaminocarbonyl, di- (C ₁ - to C ₂₀ -alkyl) amino-carbonyl, C ₁ - to C ₂₀ -alkylamino, di- (C ₁ - to C ₂₀ -alkyl) amino, C ₁ - to C ₂ o-alkylsulfonyl, wherein said alkyl, alkenyl and alkynyl groups

^{* may be} partially or completely halogenated; and / or 0 ^* can carry one to three of the following groups:

Hydroxy, sulfo, cyano, nitro, amino, aminocarbonyl, di (C ₁ - to C ₆ - alkyl) amino, C ₁ - to C ₆ alkylcarbonyl, C ₁ - to C ₆ alkyloxycarbonyl, C ₃ - to C ₈ Cycloalkyl, phenyl, phenoxy, where the C ₃ to C ₈ cycloalkyl, phenyl and phenoxy groups in turn may be partially or completely halogenated 5 and / or may carry one to three of the following groups:

Hydroxy, sulfo, cyano, nitro, amino, aminocarbonyl, C ₁ - to C ₆ -alkyl, C ₁ - to Ce-haloalkyl, C ₁ - to C ₆ -alkyloxy, C ₁ - to C ₆ -haloalkyloxy, C ₁ - to Ce-alkyloxycarbonyl, C ₁ - to C ₆ -alkylcarbonyl; and or

in which one to five CH ₂ groups can be replaced by oxygen, where 0 between at least two oxygen heteroatoms is at least one, one

Contains carbon atom-containing group;

C ₃ to C ₈ cycloalkyl, this being

* may be partially or completely halogenated; and / or 5 * can carry one to three of the following groups: Hydroxy, sulfo, cyano, nitro, amino, aminocarbonyl, C ₁ - to C ₆ -alkyl, C _r to Ce-haloalkyl, d- to C ₆ alkyloxy, C ₁ - to C ₆ -Halogenalkyloxy, C ₁ - to C ₆ -alkyloxycarbonyl, C ₁ - to C ₆ -alkylcarbonyl; and or

in which one to three CH ₂ groups can be replaced by oxygen, where between two oxygen heteroatoms at least one, one

Contains carbon atom-containing group;

Phenyl, phenoxy, which in turn

* may be partially or completely halogenated; and / or * may carry one to three of the following groups:

Hydroxy, sulfo, cyano, nitro, amino, aminocarbonyl, C ₁ - to C ₆ -alkyl, C ₁ - to Ce-haloalkyl, C ₁ - to C ₆ -alkyloxy, C ₁ - to C ₆ -haloalkyloxy, C ₁ - to C ₆ alkyloxycarbonyl, C ₁ to C ₆ alkylcarbonyl;

R ⁴ :

sulfo;

C ₁ - to C ₂₀ -alkyl, C ₂ - to C ₂₀ -alkenyl, C ₂ - to C ₂₀ -alkynyl, where the said alkyl, alkenyl and alkynyl groups ^{* may be} partially or fully halogenated; and or

* can carry one to three of the following groups:

Hydroxy, sulfo, cyano, nitro, amino, aminocarbonyl, di (C ₁ - to C ₆ alkyl) - amino, C ₁ - to C ₆ alkylcarbonyl, C ₁ - to C ₆ alkyloxycarbonyl, C ₃ - to C ₈ - cycloalkyl, phenyl, phenoxy, where the C ₃ - to C ₈ -cycloalkyl, phenyl and phenoxy groups may in turn be partially or completely halogenated and / or may carry one to three of the following groups: hydroxyl, sulfo, cyano, nitro, amino, aminocarbonyl, C ₁ - to C ₆ -alkyl, C ₁ - to C ₆ - halogenoalkyl, C ₁ - to C ₆ alkyloxy, d- to C ₆ -Halogenalkyloxy, C ₁ - to C ₆ - alkyloxycarbonyl, C ₁ - to C ₆ -alkylcarbonyl; and / or * one to five CH ₂ groups may be replaced by oxygen, wherein at least one group containing one carbon atom is located between two oxygen heteroatoms;

C ₃ - to C ₈ -cycloalkyl, where this ^{* may be} partially or completely halogenated; and or

^* can carry one to three of the following groups:

Hydroxy, sulfo, cyano, nitro, amino, aminocarbonyl, C ₁ - to C ₆ -alkyl, C ₁ - to C ₆ -haloalkyl, C ₁ - to C ₆ -alkyloxy, C ₁ - to C ₆ -haloalkyloxy, C ₁ - to C ₆ -alkyloxycarbonyl, C ₁ - to C ₆ -alkylcarbonyl; and / or * in which one to three CH ₂ groups may be replaced by oxygen, where at least one group containing one carbon atom is located between two oxygen heteroatoms; Phenyl, this being

* may be partially or completely halogenated; and or

* may carry one to three of the following groups: hydroxy, sulfo, cyano, nitro, amino, aminocarbonyl, C ₁ - to C ₆ -alkyl, C ₁ - to C ₆ -haloalkyl, C ₁ - to C ₆ -alkyloxy, C ₁ - to C ₆ -Halogenalkyloxy, C ₁ - to Ce alkyloxycarbonyl, C ₁ - to C ₆ alkylcarbonyl;

or

R ¹ together with R ⁴ , and / or R ² together with R ³ , or R ⁴ together with R ² :

Alkylene - (CH ₂ ) _n - with n = 4, 5 or 6, this being

Hydroxy, sulfo, cyano, nitro, amino, aminocarbonyl, C ₁ - to C ₆ -alkyl, C ₁ - to C ₆ -haloalkyl, C ₁ - to C ₆ -alkyloxy, C ₁ - to C ₆ -haloalkyloxy, C ₁ - to C ₆ -alkylcarbonyl, C ₁ - to C ₆ -alkyloxycarbonyl, C ₃ - to C ₈ -cycloalkyl, phenyl, phenoxy, where the C ₃ - to C ₈ -cycloalkyl, phenyl and phenoxy groups in their turn partially or may be fully halogenated and / or may carry one to three of the following groups: hydroxy, sulfo, cyano, nitro, amino, aminocarbonyl, C ₁ - to C ₆ -alkyl, C ₁ - to C ₆ -haloalkyl, C ₁ - to C ₆ - alkyloxy, C ₁ - to C ₆ -Halogenalkyloxy, C ₁ - to C ₆ alkyloxycarbonyl, C ₁ - to C ₆ alkylcarbonyl; and / or * one or two of the CH ₂ groups may be replaced by oxygen or NR ⁵ , with at least one group containing one carbon atom between two heteroatoms;

Butadienylene -CH = CH-CH = CH-, which * may carry one to three of the following groups:

Hydroxy, sulfo, cyano, nitro, amino, aminocarbonyl, C ₁ - to C ₆ -alkyl, C ₁ - to C ₆ -haloalkyl, C ₁ - to C ₆ -alkyloxy, C ₁ - to C ₆ -haloalkyloxy, C ₁ - to Ce-alkylcarbonyl, C ₁ - to C ₆ -alkyloxycarbonyl, C ₃ - to C ₈ -cycloalkyl, phenyl, phenoxy, where the C ₃ - to C ₈ -cycloalkyl, phenyl and phenoxy groups on the other hand, partially or completely may be halogenated and / or may carry one to three of the following groups: hydroxy, sulfo, cyano, nitro, amino, aminocarbonyl, C ₁ - to C ₆ -alkyl, C ₁ - to C ₆ -haloalkyl, C ₁ - to C ₆ - alkyloxy, C ₁ - to C ₆ -haloalkyloxy, C ₁ - to C ₆ -alkyloxycarbonyl, C ₁ - to C ₆ -alkylcarbonyl; and / or ^* one or two of the CH groups may be replaced by NR ⁵ , with at least one group containing one carbon atom between two heteroatoms; R ^5:

Hydrogen, C ₁ - to C ₆ -alkyl, C ₁ - to C ₆ -haloalkyl or C ₁ - to C ₆ -alkyloxy.

Imidazolium salts are important substances which find wide application. For example, they are used as fabric softener active ingredients, in hygiene and cosmetics, as phase transfer catalysts or as conductive salts for electronic applications. Another important application group is ionic liquids.

Imidazolium salts are usually prepared by alkylation of the corresponding imidazole.

WO 96/18459 discloses the preparation of halide-free ionic liquids by reacting a halide of the desired imidazolium, pyridinium or phosphonium cation with a lead salt whose anion is the anion desired for the ionic liquid and separating the precipitated lead halide. A disadvantage of the process described is the use of stoichiometric amounts of toxic, generally readily water-soluble lead salts and the accumulation of stoichiometric amounts of lead halides, which are to be disposed of or reprocessed.

WO 02/34722 teaches two synthetic routes for the preparation of 1,3,3-substituted, 1,2,3,4-substituted and 1,2,3,4,5-substituted imidazolium salts: (1) in the first route For example, the corresponding substituted imidazole is reacted with an organic halide and the halide ion of the substituted imidazolium halide is exchanged for the desired anion by ion exchange. (2) In the second route, the corresponding substituted imidazole is reacted with an alkyl triflate or a trialkyloxonium salt of the desired anion (e.g., triethyloxonium tetrafluoroborate). A disadvantage of both production methods is the high expense of the subsequently required ion exchange and the optionally associated extraction of the product with an organic solvent. During production via route (1), the remaining residual content of halide ions is also disadvantageous, which is particularly troublesome when the ionic liquid is used in the electronics industry or in catalysis. Another disadvantage in the production via route (2) is that the trialkyloxonium salts to be used are obtainable only by a relatively complex preparation and thus preclude their technical use both in terms of availability and in terms of cost-effectiveness.

EP-A 1 182 196 teaches the halide-free preparation of 1,3-substituted imidazolium salts by reacting the underlying 1-substituted imidazole with the corresponding organic disulfate as alkylating agent and subsequent ion exchange with a metal salt which contains the desired anion. This is done for example, the preparation of 1-butyl-3-methyl-imidazolium tetrafluoroborate by reacting 1-butylimidazole with dimethyl sulfate, subsequent treatment with sodium tetrafluoroborate and multiple extraction of the product with methylene chloride. Although the abovementioned process leads to apparently chloride-free 1,3-substituted imidazolium salts, it has the decisive disadvantage of using organic disulphate, which because of its carcinogenic and corrosive action represents an increased safety risk and therefore requires an enormous amount of safety. Furthermore, ion exchange by the addition of a metal salt which contains the desired anion is very complicated, especially since the batch is subsequently to be worked up by extraction using an organic solvent.

In each case via the alkylating agent, an anion is introduced into the abovementioned synthesis routes, which anion must then be exchanged for the desired anion by a classical anion exchange. This replacement is technically complicated and is generally not complete, so that the product still has disturbing contamination. This also applies to chloride-free synthesis routes, such as using dialkyl sulfate as the alkylating agent, since at least small amounts of undesired sulfate remain in the product during an anion exchange. EP-A 0 291 074 teaches the preparation of quaternary ammonium salts in a two-step reaction by reacting a tertiary amine with a carbonic acid diester to form a quaternary ammonium carbonate and mixing the resulting quaternary ammonium carbonate with an acid with removal of carbon dioxide and formation of the quaternary ammonium salt ,

EP-A 1 398 318 discloses the halide-free preparation of 1,3-substituted imidazolium salts by reacting the underlying 1-substituted imidazole with a carbonic acid diester and then reacting the resulting reaction product with the desired protic acid or its salt to introduce the desired anion.

Compared with the alkylating agents mentioned above, the alkylcarbonate anion formed in the alkylation can in principle be completely removed even without classical ion exchange, namely by decomposition into the corresponding alkyl alcohol and gaseous carbon dioxide. However, a disadvantage of the use of dialkyl carbonate as Alkylie¬ agent is its inertness, so that, in general Reaktions¬ of about 100 ⁰ C and an elevated pressure (eg autoclave) temperatures are required.

It was an object of the present invention to find a starting compound for the preparation of ionic liquids containing a 1,3-disubstituted imidazolium cation, which is simple without the use of toxic alkylating agents, using a readily available, readily available and reactive alkylating agent , in high yield and high purity can be represented, the high purity should be achievable without extensive purification. Furthermore, the starting compound to be found should be able to be converted simply and flexibly into the desired ionic liquid with the desired anion, and be presentable in high yield and high purity, even without separate, complicated purification.

Accordingly, the imidazolium methyl sulfites of the general formula (I) have been found.

Where:

• Halogen:

Fluorine, chlorine, bromine, iodine;

• Cr to C _2O -alkyl which may be * partially or completely halogenated; and or

* can carry one to three of the following groups:

Hydroxy, sulfo, cyano, nitro, amino, aminocarbonyl, di (C ₁ - to C ₆ - alkyl) amino, Cr to C ₆ alkylcarbonyl, Cr to C ₆ alkyloxycarbonyl, C ₃ - to Cβ cycloalkyl, phenyl, Phenoxy, where the C ₃ - to C ₈ -cycloalkyl, phenyl and phenoxy groups may in turn be partially or fully halogenated and / or may carry one to three of the following groups: hydroxyl, sulfo, cyano, nitro, amino, aminocarbonyl, Cr to C ₆ alkyl, C ₁ - to C ₆ haloalkyl, C ₁ - to C ₆ alkyloxy, C ₁ - to C ₆ -Halogenalkyloxy, C ₁ - to C ₆ alkyloxycarbonyl, C ₁ - to C ₆ - alkylcarbonyl; and / or * one to five CH ₂ groups may be replaced by oxygen, wherein at least one group containing one carbon atom is located between two oxygen heteroatoms; for example, methyl, ethyl, 1-propyl, 2-propyl, 1-butyl, 2-butyl, 2-methyl-1-propyl (isobutyl), 2-methyl-2-propyl (tert-butyl), 1-pentyl, 2-pentyl, 3-pentyl, 2-methyl-1-butyl, 3-methyl-1-butyl, 2-methyl-2-butyl, 3-methyl-2-butyl, 2,2-dimethyl-1-propyl,

1-hexyl, 2-hexyl, 3-hexyl, 2-methyl-1-pentyl, 3-methyl-1-pentyl, 4-methyl-1-pentyl, 2-methyl-2-pentyl, 3-methyl-2- pentyl, 4-methyl-2-pentyI, 2-methyl-3-pentyl, 3-methyl-3-pentyl, 2,2-dimethyl-1-butyl, 2,3-dimethyl-1-butyl, 3,3- Dimethyl-1-butyl, 2-ethyl-1-butyl, 2,3-dimethyl-2-butyl, 3,3-dimethyl-2-butyl, 1-heptyl, 1-octyl, 2-ethylhexyl, 2,4, 4-trimethylpentyl, 1, 1, 3,3-tetramethylbutyl, 1 -nonyl, 1-decyl,

1-undecyl, 1-dodecyl, 1-tridecyl, 1-tetradecyl, 1-pentadecyl, 1-hexadecyl, 1-heptadecyl, 1-octadecyl, 1-nonadecyl, 1-eicosyl, cyclopentylmethyl, 2-cyclopentylethyl, 3 Cyclopentylpropyl, cyclohexylmethyl, 2-cyclohexylethyl, 3-cyclohexylpropyl, benzyl (phenylmethyl), diphenylmethyl (benzhydryl), triphenylmethyl, 1-phenylethyl, 2-phenylethyl, 3-phenylpropyl, α, α-dimethylbenzyl, p-tolylmethyl,

1- (p-butylphenyl) ethyl, p-chlorobenzyl, 2,4-dichlorobenzyl, p -methoxybenzyl, m-ethoxybenzyl, 2-cyanoethyl, 2-cyanopropyl, 2-methoxycarbonylethyl, 2-ethoxy carbonylethyl, 2-butoxycarbonylpropyl, 1, 2-di- (methoxycarbonyl) ethyl, 2-hydroxyethyl, 2-hydroxypropyl, 3-hydroxypropyl, 4-hydroxybutyl, 6-hydroxyhexyl, 2-aminoethyl, 2-aminopropyl, 3-aminopropyl , 4-aminobutyl, 6-aminohexyl, 2-methylaminoethyl, 2-methylaminopropyl, 3-methylaminopropyl, 4-methylaminobutyl, 6-methylaminohexyl, 2-dimethylaminoethyl, 2-dimethylaminopropyl,

3-dimethylaminopropyl, 4-dimethylaminobutyl, 6-dimethylaminohexyl, 2-hydroxy-2,2-dimethylethyl, 2-phenoxyethyl, 2-phenoxypropyl, 3-phenoxypropyl, 4-phenoxybutyl, 6-phenoxyhexyl, methoxymethyl, 2-methoxyethyl, 2-methoxypropyl, 3-methoxypropyl, 4-methoxybutyl, 6-methoxyhexyl, 2-ethoxyethyl, 2-ethoxypropyl, 3-ethoxypropyl, 4-ethoxybutyl, 6-ethoxyhexyl, 2-butoxyethyl, 2-isopropoxyethyl,

2-butoxypropyl, 2-octyloxyethyl, 2-methoxyisopropyl, diethoxymethyl, Diethoxye- methyl, 2- (methoxycarbonyl) ethyl, 2- (ethoxycarbonyl) ethyl, 2- (n-butoxycarbonyl) ethyl, C _n F (π ₂ ₊ i) -aH _a with n equal to 1 to 20, 0 <a <2n + 1 (for example CF ₃ , C ₂ F ₅ , CH ₂ CH ₂ -C (n- ₂ ) F _{2 (n} . ₂ ) ₊₁ , C ₆ F ₁₃ , C ₈ F ₁₇ , C ₁₀ F ₂₁ , C ₁₂ F ₂₅ ), C _n Cl ₍₂ n ₊₁₎ -a ₎ H _a with n equal to 1 to 20, 0 <a <2n + 1, chloromethyl, 2-chloroethyl, trichloromethyl, 1, 1-dimethyl-2-chloroethyl,

2,2,2-trifluoroethyl, 5-hydroxy-3-oxa-pentyl, 8-hydroxy-3,6-dioxo-octyl, 11-hydroxy-3,6,9-trioxa-undecyl, 7-hydroxy-4 -oxa-heptyl, 11-hydroxy-4,8-dioxa-undecyl, 15-hydroxy-4,8,12-trioxa-pentadecyl, 9-hydroxy-5-oxa-nonyl, 14-hydroxy-5,10-dioxa -tetradecyl, 5-methoxy-3-oxa-pentyl, 8-methoxy-3,6-dioxo-octyl, 11-methoxy-3,6,9-trioxa-undecyl, 7-methoxy-4-oxa-heptyl, 11 methoxy-4,8-dioxa-undecyl,

15-methoxy-4,8,12-trioxa-pentadecyl, 9-methoxy-5-oxa-nonyl, 14-methoxy-5,10-dioxa-tetradecyl, 5-ethoxy-3-oxa-pentyl, 8-ethoxy 3,6-dioxo-octyl, 11-ethoxy-3,6,9-trioxa-undecyl, 7-ethoxy-4-oxa-heptyl, 11-ethoxy-4,8-dioxa-undecyl, 15-ethoxy-4, 8,12-trioxa-pentadecyl, 9-ethoxy-5-oxa-nonyl, 14-ethoxy-5,10-dioxa-tetradecyl;

C ₂ to C ₂₀ alkenyl, which

^{* may be} partially or completely halogenated; and or

* can carry one to three of the following groups:

Hydroxy, sulfo, cyano, nitro, amino, aminocarbonyl, di- (C ₁ - to C ₆ -alkyl) amino, C ₁ - to C ₆ -alkylcarbonyl, C ₁ - to C ₆ -alkyloxycarbonyl, C ₃ - to

Cs-cycloalkyl, phenyl, phenoxy, where the C ₃ - to C ₈ -cycloalkyl, phenyl and phenoxy groups in turn may be partially or fully halogenated and / or may carry one to three of the following groups: hydroxy, sulfo, cyano, Nitro, amino, aminocarbonyl, C ₁ - to C ₆ -alkyl, C ₁ - to C ₆ -haloalkyl, C ₁ - to C ₆ -alkyloxy, C ₁ - to C ₆ -haloalkyloxy, C ₁ - to

C ₆ alkyloxycarbonyl, C ₁ to C ₆ alkylcarbonyl; and or

in which one to five CH ₂ groups can be replaced by oxygen, wherein at least one group containing one carbon atom is located between two oxygen heteroatoms; for example, ethenyl (vinyl), propen-1-yl, propen-2-yl, propen-3-yl, 2-phenyl-ethenyl (styryl); • C ₂ - to C ₂ o-alkynyl, which

* may be partially or completely halogenated; and or

* can carry one to three of the following groups:

C ₈ -cycloalkyl, phenyl, phenoxy, where the C ₃ - to C ₈ -cycloalkyl, phenyl and phenoxy groups in turn may be partially or fully halogenated and / or may carry one to three of the following groups: hydroxy, sulfo, cyano , Nitro, amino, aminocarbonyl, C ₁ - to C ₆ -alkyl, C ₁ - to C ₆ -haloalkyl, C ₁ - to C ₆ -alkyloxy, C ₁ - to C ₆ -haloalkyloxy, C ₁ - to

C ₆ alkyloxycarbonyl, C ₁ to C ₆ alkylcarbonyl; and or

in which one to five CH ₂ groups can be replaced by oxygen, where between two oxygen heteroatoms there is at least one group containing a carbon atom; for example, ethynyl, 1-propynyl, 3-propynyl, 2-phenylethynyl;

C ₁ -C ₂₀ -alkyloxy, which

* may be partially or completely halogenated; and or

* may carry one to three of the following groups: hydroxy, sulfo, cyano, nitro, amino, aminocarbonyl, di (C ₁ - to C ₆ -alkyl) amino, C ₁ - to C ₆ -alkylcarbonyl, C ₁ - to C _6- alkyloxycarbonyl, C ₃ - to Cβ-cycloalkyl, phenyl, phenoxy, where the C ₃ - to C ₈ -cycloalkyl, phenyl and phenoxy groups in turn may be partially or fully halogenated and / or carry one to three of the following groups may be: hydroxy, sulfo, cyano, nitro, amino, aminocarbonyl, C ₁ - to C ₆ -alkyl, C ₁ - to C ₆ -haloalkyl, C ₁ - to C ₆ -alkyloxy, C ₁ - to C ₆ -haloalkyloxy, C ₁ to C ₆ alkyloxycarbonyl, C ₁ to C ₆ alkylcarbonyl; and or

^* Therein a may be replaced to five CH ₂ groups are replaced by oxygen, it being possible for between two oxygen heteroatoms is at least one, a carbonic group-containing lenstoffatom located; for example, methoxy, ethoxy, 1-propoxy, 1-butoxy, 1-pentoxy, 1-hexoxy, 2-hydroxyethoxy, 2-methoxyethoxy, 2-ethoxyethoxy, 2-propoxyethoxy, 2-butoxyethoxy, 2-phenoxyethoxy, 5-hydroxy 3-oxa-pentyloxy, 5-methoxy-3-oxa-pentyloxy, 5-ethoxy-3-oxa-pentyloxy, 5-propoxy-3-oxa-pentyloxy, 5-butoxy-3-oxa-pentyloxy, 5-phenoxy 3-oxa-pentyloxy, 8-hydroxy-3,6-dioxa-hexyloxy, 8-methoxy-3,6-dioxa-hexyloxy, 8-ethoxy-3,6-dioxa-hexyloxy, 8-propoxy-3,6 dioxa-hexyloxy, 8-butoxy-3,6-dioxa-hexyloxy, 8-phenoxy-3,6-dioxa-hexyloxy, 3-hydroxypropoxy, 3-methoxypropoxy, 3-ethoxypropoxy, 3-propoxypropoxy, 3-butoxypropoxy , 3-phenoxypropoxy, 7-hydroxy-4-oxa-heptyloxy, 7-methoxy-4-oxa-heptyloxy, 7-ethoxy-4-oxa-heptyloxy, 7-propoxy-4-oxa-heptyloxy, 7-butoxy-4 -oxa-heptyloxy, 7-phenoxy-4-oxa-heptyloxy, 11-hydroxy-4,8-dioxa-undecyloxy, 11-methoxy-4,8-dioxa-undecyloxy, 11-ethoxy-4,8-dioxa-undecyloxy , 11-propoxy-4,8-dioxa-undecyloxy, 11-butoxy-4,8-dioxa- undecyloxy, 11-phenoxy-4,8-dioxa-undecyloxy, 4-hydroxybutoxy, 4-methoxybutoxy, 4-ethoxybutoxy, 4-propoxybutoxy, 4-butoxybutoxy, 4-phenoxybutoxy, 9-hydroxy-5-oxa-nonyloxy, 9- Methoxy-5-oxa-nonyloxy, 9-ethoxy-5-oxa-nonyloxy, 9-propoxy-5-oxa-nonyloxy, 9-butoxy-5-oxa-nonyloxy, 9-phenoxy-5-oxa-nonyloxy, 14- Hydroxy-5,10-dioxa-tetradecyloxy, 14-methoxy-5,10-dioxa-tetradecyloxy, 14-ethoxy-5,10-dioxa-tetradecyloxy, 14-propoxy-5, 10-dioxa-tetradθcyloxy, 14-butoxy- 5,10-dioxatetradecyloxy, 14-phenoxy-5,10-dioxa-tetradecyloxy;

• C ₂ - to C ₂₀ alkenyloxy, which ^* may be partially or fully halogenated; and or

^* can carry one to three of the following groups:

Hydroxy, SuIf o, cyano, nitro, amino, aminocarbonyl, di- (Cr to C ₆ alkyl) amino, C ₁ - to C ₆ alkylcarbonyl, C ₁ - to C ₆ alkyloxycarbonyl, C ₃ - to Cs-cycloalkyl , Phenyl, phenoxy, where the C ₃ - to C ₈ -cycloalkyl, phenyl and phenoxy groups in turn may be partially or fully halogenated and / or may carry one to three of the following groups: hydroxy, sulfo, cyano, nitro, amino , Aminocarbonyl, C ₁ - to C ₆ -alkyl, C ₁ - to Ce-haloalkyl, C ₁ - to C ₆ -alkyloxy, C ₁ - to C ₆ -haloalkyloxy, C ₁ - to C ₆ -alkyloxycarbonyl, C ₁ - to C ₆ alkylcarbonyl; and / or ^* one to five CH ₂ groups may be replaced by oxygen, wherein at least one group containing one carbon atom is present between two oxygen heteroatoms; for example, prop-2-enyloxy;

• C ₂ - to C ₂ o-alkynyloxy, which

^{* may be} partially or completely halogenated; and or

* can carry one to three of the following groups:

Hydroxy, sulfo, cyano, nitro, amino, aminocarbonyl, di- (C ₁ - to C ₆ -alkyl) amino, C ₁ - to C ₆ -alkylcarbonyl, C ₁ - to C ₆ -alkenyloxycarbonyl, C ₃ - to Cs -Cycloalkyl, phenyl, phenoxy, wherein the C ₃ - to C ₈ -cycloalkyl, phenyl and phenoxy groups in turn may be partially or fully halogenated and / or may carry one to three of the following groups: hydroxy, sulfo, cyano, nitro , Amino, aminocarbonyl, C ₁ - to C ₆ -alkyl, C ₁ - to Ce-haloalkyl, C ₁ - to C ₆ -alkyloxy, C ₁ - to C ₆ -haloalkyloxy, C ₁ - to Ce-alkyloxycarbonyl, C ₁ - to C ₆ alkylcarbonyl; and or

in which one to five CH ₂ groups can be replaced by oxygen, wherein at least one group containing one carbon atom is located between two oxygen heteroatoms; for example, prop-2-ynyloxy;

C ₁ to C ₂₀ alkylcarbonyl, which

* may be partially or completely halogenated; and or * can carry one to three of the following groups:

Hydroxyl, sulfo, cyano, nitro, amino, aminocarbonyl, di (C ₁ - to C ₆ -alkyl) amino, C ₁ - to C ₆ -alkylcarbonyl, C ₁ - to C ₆ -alkyloxycarbonyl, C ₃ - to Cβ- Cycloalkyl, phenyl, phenoxy, where the C ₃ - to C ₈ -cycloalkyl, phenyl and phenoxy groups may in turn be partially or completely halogenated and / or may carry one to three of the following groups: hydroxyl, sulfo, cyano, nitro, Amino, aminocarbonyl, C ₁ - to C ₆ -alkyl, C ₁ - to C ₆ -haloalkyl, C ₁ - to C ₆ -alkyloxy, C ₁ - to C ₆ -haloalkyloxy, C ₁ - to Ce-alkyloxycarbonyl, C ₁ - to C ₆ alkylcarbonyl; and / or * one to five CH ₂ groups may be replaced by oxygen, wherein at least one group containing one carbon atom is located between two oxygen heteroatoms; for example, acetyl, propionyl, 1-oxobutyl (butyryl), 1-oxopentyl, 1-oxohexyl, 1-oxoheptyl, 1-oxooctyl, 1-oxononyl, 1-oxodecyl, 1-oxoundecyl, 1-oxododecyl, 1-oxotetradecyl, 1 - Oxohexadecyl, 1-oxooctadecyl, 1-oxoeicosyl, 1, 3-dioxobutyl, phenylacetyl, 3-phenylpropionyl, 1-oxo-4-phenylbutyl (4-phenylbutyryl), benzoyl;

C ₁ to C ₂₀ alkyloxycarbonyl, which

^{* may be} partially or completely halogenated; and / or * may carry one to three of the following groups:

Hydroxy, sulfo, cyano, nitro, amino, aminocarbonyl, di (C ₁ - to C ₆ - alkyl) amino, C ₁ - to C ₆ -alkylcarbonyl, C ₁ - to C ₆ -alkyloxycarbonyl, C ₃ - to Cs Cycloalkyl, phenyl, phenoxy, where the C ₃ - to C ₈ -cycloalkyl, phenyl and phenoxy groups may in turn be partially or completely halogenated and / or may carry one to three of the following groups:

Hydroxy, sulfo, cyano, nitro, amino, aminocarbonyl, C ₁ - to C ₆ -alkyl, C ₁ - to C ₆ -haloalkyl, C ₁ - to C ₆ -alkyloxy, C ₁ - to C ₆ -haloalkyloxy, C ₁ - to C ₆ -alkyloxycarbonyl, C ₁ - to C ₆ -alkylcarbonyl; and or

in which one to five CH ₂ groups can be replaced by oxygen, in which there is at least one group containing one carbon atom between two oxygen heteroatoms; for example, methyloxycarbonyl (CH ₃ -O-CO-), ethyloxycarbonyl, 1-propyloxycarbonyl, 1-butyloxycarbonyl, 1-pentyloxycarbonyl, 1-hexyloxycarbonyl, 1-heptyloxycarbonyl, 1-octyloxycarbonyl;

C ₁ to C ₂₀ acyloxy, which

* may be partially or completely halogenated; and or

* can carry one to three of the following groups:

Cs-cycloalkyl, phenyl, phenoxy, wherein the C ₃ - to C ₈ -cycloalkyl, phenyl and phenoxy groups in turn be partially or fully halogenated can and / or carry one to three of the following groups: hydroxy, sulfo, cyano, nitro, amino, aminocarbonyl, C ₁ - to C ₆ -alkyl, C ₁ - to Ce-haloalkyl, C ₁ to C ₆ -alkyloxy, C ₁ - to C ₆ -Halogenalkyloxy, C ₁ - to C ₆ alkyloxycarbonyl, C ₁ - to C ₆ alkylcarbonyl; and / or * one to five CH ₂ groups may be replaced by oxygen, wherein at least one group containing one carbon atom is present between two oxygen heteroatoms; for example, acetoxy, propionyloxy, 1-oxobutyloxy (butyryloxy), 1-oxopentyloxy,

1-oxohexyloxy, 1-oxoheptyloxy, 1-oxo-octyloxy, 1-oxononyloxy, 1-oxodecyloxy, 1-oxo-decyloxy, 1-oxododecyloxy, 1-oxotetradecyloxy, 1-oxohexadecyloxy, 1 -

Oxooctadecyloxy, 1-oxoeicosyloxy, phenylacetoxy, 3-phenylpropionyloxy, 1-oxo-4-phenylbutyloxy (4-phenylbutylyloxy), benzoyloxy;

C ₁ - to C ₂₀ -alkylaminocarbonyl, di (C ₁ - to C ₂ o-alkyl) aminocarbonyl, which * may be partially or completely halogenated; and or

* can carry one to three of the following groups:

Hydroxyl, sulfo, cyano, nitro, amino, aminocarbonyl, di (C ₁ - to C ₆ -alkyl) amino, C ₁ - to C ₆ -alkylcarbonyl, C ₁ - to C ₆ -alkyloxycarbonyl, C ₃ - to Cβ- Cycloalkyl, phenyl, phenoxy, where the C ₃ - to C ₈ -cycloalkyl, phenyl and phenoxy groups may in turn be partially or completely halogenated and / or may carry one to three of the following groups: hydroxyl, sulfo, cyano, nitro, Amino, aminocarbonyl, C ₁ - to C ₆ -alkyl, C ₁ - to Ce-haloalkyl, C ₁ - to C ₆ -alkyloxy, C ₁ - to C ₆ -haloalkyloxy, C ₁ - to C ₆ -alkyloxycarbonyl, C ₁ - to C ₆ alkylcarbonyl; and / or ^* one to five CH ₂ groups may be replaced by oxygen, wherein at least one group containing one carbon atom is present between two oxygen heteroatoms; for example, N-methylaminocarbonyl, N-ethylaminocarbonyl, N- (1-propyl) aminocarbonyl, N- (2-propyl) aminocarbonyl, N- (1-butyl) aminocarbonyl, N- (2-butyl) aminocarbonyl, N - (2-methyl-1-propyl) aminocarbonyl (N-isobutylaminocarbonyl), N- (2-

Methyl-2-propyl) aminocarbonyl (N-tert-butylaminocarbonyl), N- (1-pentyl) aminocarbonyl, N- (2-pentyl) aminocarbonyl, N- (3-pentyl) aminocarbonyl, N- (2- Methyl-1-butyl) aminocarbonyl, N- (3-methyl-1-butyl) aminocarbonyl, N- (2-methyl-2-butyl) -aminocarbonyl, N- (3-methyl-2-butyl) aminocarbonyl, N- (2,2-dimethyl-1-propyl) -aminocarbonyl, N- (1-hexyl) aminocarbonyl, N- (2-hexyl) aminocarbonyl, N- (3-hexyl) -aminocarbonyl, N- (2-methyl-1 -pentyl) aminocarbonyl, N- (3-methyl-1-pentyl) -aminocarbonyl, N- (4-methyl-1-pentyl) aminocarbonyl, N- (2-methyl-2-pentyl) -aminocarbonyl, N- (3 Methyl 2-pentyl) aminocarbonyl, N- (4-methyl-2-pentyl) aminocarbonyl, N- (2-methyl-3-pentyl) aminocarbonyl, N- (3-methyl-3-pentyl) aminocarbonyl, N- (2,2-dimethyl-1-butyl) aminocarbonyl, N- (2,3-dimethyl-1-butyl) -aminocarbonyl, N- (3,3-dimethyl-1-butyl) aminocarbonyl, N- (2 Ethyl-1-butyl) -aminocarbonyl, N- (2,3-dimethyl-2-butyl) -aminocarbonyl, N- (3,3-dimethyl-2-) butyl) aminocarbonyl, N- (heptyl) aminocarbonyl, N- (octyl) aminocarbonyl, N- (2-ethylhexyl) aminocarbonyl, N- (2,4,4-trimethylpentyl) aminocarbonyl, N- (1,1,3,3 - tetramethylbutyl) aminocarbonyl, N- (1 -nonyl) aminocarbonyl, N- (1-decyl) -aminocarbonyl, N- (1-undecyl) aminocarbonyl, N- (1-dodecyl) aminocarbonyl, N- (1-tetradecyl) aminocarbonyl , N- (1-hexadecyl) aminocarbonyl, N- (1-octadecyl) aminocarbonyl, N- (1-eicosyl) aminocarbonyl, N, N-dimethylaminocarbonyl, N, N -diethylaminocarbonyl, N, N -di (1-propyl ) aminocarbonyl, N, N-di (2-propyl) -aminocarbonyl, N, N-di (1-butyl) aminocarbonyl, N, N-di (2-butyl) aminocarbonyl, N, N-di (2-methyl) 1-propyl) aminocarbonyl (N, N-diisobutylaminocarbonyl), N, N -di (2-methyl-2-propyl) aminocarbonyl (N, N-di-tert-butylaminocarbonyl), N ₁ N -di ( I -pentyl) - aminocarbonyl, N, N -di (2-pentyl) aminocarbonyl, N, N -di (3-pentyl) aminocarbonyl, N, N -di (2-methyl-1-butyl) aminocarbonyl, N, N Di (3-methyl-1-butyl) aminocarbonyl, N ₎ N -di (2-methyl-2-butyl) aminocarbonyl, N, N -di (3-methyl-2-butyl) a minocarbonyl, N, N-di (2,2-dimethyl-1-propyl) aminocarbonyl, N, N-di (1-hexyl) aminocarbonyl, N, N -di (2-hexyl) aminocarbonyl, N, N -di ( 3-hexyl) aminocarbonyl, N, N -di (2-methyl-1-pentyl) aminocarbonyl, N, N -di (3-methyl-1-pentyl) aminocarbonyl, N, N-di (4-methyl-1 - pentyl) aminocarbonyl, N, N -di (2-methyl-2-pentyl) aminocarbonyl, N, N -di (3-methyl-2-pentyl) aminocarbonyl, N, N -di (4-methyl-2-pentyl) aminocarbonyl, N, N -di (2-methyl-3-pentyl) aminocarbonyl, N, N -di (3-methyl-3-pentyl) aminocarbonyl, N, N -di (2,2-dimethyl-1-butyl) aminocarbonyl, N, N-di (2,3-dimethyl-1-butyl) aminocarbonyl, N ₁ N-

Di (3,3-dimethyl-1-butyl) aminocarbonyl, N, N-di (2-ethyl-1-butyl) aminocarbonyl, N, N-di (2,3-dimethyl-2-butyl) aminocarbonyl, N, N-di (3,3-dimethyl-2-butyl) aminocarbonyl, N, N-di (I -heptyl) aminocarbonyl, N ₁ N -di (I -octyl) aminocarbonyl, N, N-di (2-ethyl) hexyl) aminocarbonyl, N, N-di (2,4,4-trimethylpentyl) aminocarbonyl, N ₁ N -di (1,1,3,3-tetramethylbutyl) aminocarbonyl, N, N-di (I -nonyl) aminocarbonyl, N, N-Di (I decyl) - aminocarbonyl, N, N-di (1-undecyl) aminocarbonyl, N, N-di (dodecyl 1) aminocarbonyl, N ₁ N-Di (I -tetradecyl) aminocarbonyl, N ₁ N-di (1-hexadecyl) aminocarbonyl, N ₁ N -di (1-octadecyl) aminocarbonyl, N ₁ N -di (1 -eicosyl) aminocarbonyl, N, N -methylethylaminocarbonyl, N, N -methyl- 1-propyl) aminocarbonyl, N, N -methyl- (1-butyl) amino carbonyl, N, N-ethyl- (1-propyl) aminocarbonyl, N, N-ethyl- (1-butyl) aminocarbonyl;

C ₁ - to C ₂ o-alkylamino, di- (C ₁ - to C ₂ o-alkyl) amino, which

* may be partially or completely halogenated; and or

* may carry one to three of the following groups: hydroxy, sulfo, cyano, nitro, amino, aminocarbonyl, di- (C ₁ - to C ₆ -alkyl) amino, C ₁ - to C ₆ -alkylcarbonyl, C ₁ - to C _6- alkyloxycarbonyl, C ₃ - to C ₈ -cycloalkyl, phenyl, phenoxy, where the C ₃ - to C ₈ -cycloalkyl, phenyl and phenoxy groups in turn may be partially or completely halogenated and / or one to three of the following groups can carry: hydroxy, sulfo, cyano, nitro, amino, aminocarbonyl, C ₁ - to C ₆ -alkyl, C ₁ - to C ₆ -haloalkyl, C ₁ - to C ₆ -alkyloxy, C ₁ - to C ₆ -haloalkyloxy , C ₁ - to C ₆ -alkyloxycarbonyl, C ₁ - to C ₆ -alkylcarbonyl; and or in which one to five CH ₂ groups can be replaced by oxygen, wherein at least one group containing one carbon atom is located between two oxygen heteroatoms; For example, N-methylamino, N -ethylamino, N- (1-propyl) amino, N- (2-propyl) -amino, N- (1-butyl) amino, N- (2-butyl) amino, N- (2 -Methyl-1-propyl) amino (N-isobutylamino), N- (2-methyl-2-propyl) amino (N-tert-butylamino), N- (1-pentyl) amino, N- (2 - pentyl) amino, N- (3-pentyl) amino, N- (2-methyl-1-butyl) amino, N- (3-methyl-1-butyl) -amino, N- (2-methyl-2-amino) butyl) amino, N- (3-methyl-2-butyl) amino, N- (2,2-dimethyl-1-propyl) amino, N- (1-hexyl) amino, N- (2-hexyl) amino, N- (3-HexyI) amino, N- (2-methyl-1-pentyl) amino, N- (3-methyl-1-pentyl) amino, N- (4-methyl-1-pentyl) amino, N- (2-

Methyl-2-pentyI) amino, N- (3-methyl-2-pentyl) amino, N- (4-methyl-2-pentyl) amino, N- (2-methyl-3-pentyl) amino, N- ( 3-methyl-3-pentyI) amino, N- (2,2-dimethyl-1-butyl) -amino, N- (2,3-dimethyl-1-butyl) amino, N- (3,3-dimethyl) 1-butyl) amino, N- (2-ethyl-1-butyl) amino, N- (2,3-dimethyl-2-butyl) amino, N- (3,3-dimethyl-2-butyl) amino, N - (heptyl) amino, N- (octyl) amino, N- (2-ethylhexyl) amino, N- (2,4,4-trimethylpentyl) -amino, N- (1,1,3,3-tetramethylbutyl) amino , N- (1-nonyl) amino, N- (1-decyl) amino, N- (1-undecyl) amino, N- (1-dodecyl) amino, N- (1-tetradecyl) amino, N- (I -hexadecyl) - amino, N- (1-octadecyl) amino, N- (1-eicosyl) amino, N, N-dimethylamino, N ₇ N-di- ethylamino, N, N-Di (I -propyl) amino, N, N-di (2-propyl) amino, N ₁ N -di (1-butyl) amino, N, N -di (2-butyl) amino, N, N -di (2-methyl-1-propyl) amino (N, N-di-isobutylamino), N ₇ N-

Di (2-methyl-2-propyl) amino (N, N-di-tert-butylamino), N, N-di (1-pentyl) amino, N ₇ N -di (2-pentyl) amino, N , N-di (3-pentyl) amino, N, N -di (2-methyl-1-butyl) amino, N, N -di (3-methyl-1-butyl) amino, N, N-di (2 -methyl-2-butyl) amino, N, N -di (3-methyl-2-butyl) -amino, N, N-di (2,2-dimethyl-1-propyl) amino, N ₁ N -di ( I -hexyl) amino, N, N -di (2-hexyl) amino, N, N -di (3-hexyl) amino, N, N -di (2-methyl-1-pentyl) amino, N, N- Di (3-methyl-1-pentyl) amino, N, N -di (4-methyl-1-pentyl) amino, N, N -di (2-methyl-2-pentyl) amino, N, N-di ( 3-methyl-2-pentyI) amino, N, N -di (4-methyl-2-pentyl) amino, N, N -di (2-methyl-3-pentyl) amino, N, N-di (3) methyl-3-pentyl) amino, N, N-di (2,2-dimethyl-1-butyl) amino, N, N -di (2,3-dimethyl-1-butyl) amino, N, N-di ( 3,3-dimethyl-1-butyl) amino, N, N-di (2-ethyl-1-butyl) amino, N, N -di (2,3-dimethyl-2-butyl) amino, N ₇ N-

Di (3,3-dimethyl-2-butyl) amino, N, N -di (1-heptyl) amino, N, N-di (I -octyl) amino, N ₇ N -di (2-ethylhexyl) amino, N, N-di (2,4,4-trimethylpentyl) amino, N ₁ N-di (1, 1, 3,3-tetra- methylbutyl) amino, N ₁ N-Di (I nonyl) amino, N ₁ N-di (I decyl) amino, N ₁ N-di (I- undecyl) amino, N, N-Di (I dodecyl) amino, N, N-Di (I -tetradecyl) amino, N ₁ N- di (I-hexadecyl) amino, N ₁ N-di (I octadecyl) amino, N, N-di (1-eicosyl) amino, N, N-methyl-ethylamino, N, N-methyl- (1 -propyl ) amino, N, N -methyl- (1-butyl) amino, N, N-ethyl- (1-propyl) amino, N, N-ethyl- (1-butyl) amino;

C ₁ - to C ₂₀ -alkylsulfonyl, which * may be partially or completely halogenated; and or

* can carry one to three of the following groups: Hydroxyl, sulfo, cyano, nitro, amino, aminocarbonyl, di (C ₁ - to C ₆ -alkyl) amino, C ₁ - to C ₆ -alkylcarbonyl, C ₁ - to C ₆ -alkyloxycarbonyl, C ₃ - to Cs- Cycloalkyl, phenyl, phenoxy, where the C ₃ - to C ₈ -cycloalkyl, phenyl and phenoxy groups in turn may be partially or fully halogenated and / or may carry one to three of the following groups:

Hydroxy, sulfo, cyano, nitro, amino, aminocarbonyl, C ₁ - to C ₆ -alkyl, C ₁ - to Ce-haloalkyl, C ₁ - to C ₆ -alkyloxy, C ₁ - to C ₆ -haloalkyloxy, C ₁ - to Cβ-alkyloxycarbonyl, C ₁ - to C ₆ -alkylcarbonyl; and or

in which one to five CH ₂ groups can be replaced by oxygen, in which there is at least one group containing one carbon atom between two oxygen heteroatoms; for example, methylsulfonyl, ethylsulfonyl, 1-propylsulfonyl, 1-butylsulfonyl, 1-pentylsulfonyl, 1 -hexylsulfonyl;

C ₃ to C 6 cycloalkyl, which

* may be partially or completely halogenated; and or

* can carry one to three of the following groups:

Hydroxy, sulfo, cyano, nitro, amino, aminocarbonyl, C ₁ - to C ₆ -alkyl, C ₁ - to Ce-haloalkyl, C ₁ - to C ₆ -alkyloxy, C ₁ - to C ₆ -haloalkyloxy, C ₁ - to C ₆ alkyloxycarbonyl, C ₁ to C ₆ alkylcarbonyl; and or

^* Therein a may be replaced to five CH ₂ groups are replaced by oxygen, it being possible for between two oxygen heteroatoms is at least one, a Koh¬ lenstoffatom containing group is; For example, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cyclooctyl, cyclododecyl, 1-methylcyclopentyl, 2-methylcyclopentyl, 3-methylcyclopentyl, 1, 2-dimethylcyclopentyl, 1, 3-dimethylcyclopentyl, 2,2-dimethylcyclopentyl 2,3- Dimethylcyclopentyl, 3,3-dimethylcyclopentyl, 1-methylcyclohexyl, 2-methylcyclohexyl, 3-methylcyclohexyl, 4-methylcyclohexyl, 1, 2-dimethylcyclohexyl, 1, 3-dimethylcyclohexyl, 1, 4-dimethylcyclohexyl, 2,2- Dimethylcyclohexyl, 2,3-dimethylcyclohexyl, 2,4-dimethylcyclohexyl, 3,3-dimethylcyclohexyl, 3,4-dimethylcyclohexyl, 4,4-dimethylcyclohexyl, 1-methoxycyclopentyl, 2-methoxycyclopentyl, 3-methoxyclopentyl, 1, 2-dimethoxycyclopentyl, 1,3-dimethoxycyclopentyl, 2,2-dimethoxyclopentyl, 2,3-dimethoxycyclopentyl, 3,3-dimethoxycyclopentyl, 1-methoxycyclohexyl, 2-methoxycyclohexyl, 3-methoxycyclohexyl, 4-methoxycyclohexyl, 1, 2 -Di-methoxycyclohexyl, 1, 3-dimethoxycyclohexyl, 1, 4-dimethoxycyclohexyl, 2,2-dimethoxycyclohexyl, 2,3-dimethoxycycl ohexyl, 2,4-dimethoxycyclohexyl, 3,3-dimethoxycyclohexyl, 3,4-dimethoxycyclohexyl, 4,4-dimethoxycyclohexyl, dichlorocyclopentyl, chlorocyclohexyl, dichlorocyclohexyl, 2,3,4,5,6-pentachlorocyclohexyl, C _n F ₍ 2n-i) -aH _a with n equal to 3 to 8, 0 <a <2n-1, C _n CI ₍₂ ni) .aHa with n equal to 3 to 8, 0 <a <n-1, 1, 3-dioxolan-2-yl, 1, 3-dioxan-2-yl, 2-methyl-1,3-dioxolan-2-yl, 4-methyl

1, 3-dioxolan-2-yl, 2-methyl-1,3-dioxan-2-yl, 4-methyl-1,3-dioxan-2-yl; • phenyl, phenoxy, which

* may be partially or completely halogenated; and or

* can carry one to three of the following groups:

Hydroxy, sulfo, cyano, nitro, amino, aminocarbonyl, C ₁ - to C ₆ -alkyl, C ₁ - to C ₆ haloalkyl, d- to C ₆ alkyloxy, C ₁ - to C ₆ -Halogenalkyloxy, C ₁ - to

Ce-alkyloxycarbonyl, C ₁ to C ₆ alkylcarbonyl; for example, phenyl, 2-methylphenyl (2-ToIyI), 3-methylphenyl (3-ToIyI), 4-methylphenyl (4-ToIyI), 2-ethylphenyl, 3-ethylphenyl, 4-ethylphenyl, 2-methoxyphenyl, 3-methoxyphenyl, 4-methoxyphenyl, 2-sulfophenyl (o-tosyl), 3-sulfophenyl (m-tosyl), 4-sulfophenyl (p-tosyl), phenoxy, 2-methylphenoxy, 3

Methylphenoxy, 4-methylphenoxy, 2-ethylphenoxy, 3-ethylphenoxy, 4-ethylphenoxy, 2-methoxyphenoxy, 3-methoxyphenoxy, 4-methoxyphenoxy;

• Alkylene - (CH ₂ ) _n - with n = 4, 5 or 6, which * may be partially or completely halogenated; and or

^* can carry one to three of the following groups:

Hydroxy, sulfo, cyano, nitro, amino, aminocarbonyl, C ₁ - to C ₆ -alkyl, C ₁ - to C ₆ -haloalkyl, C ₁ - to C ₆ -alkyloxy, C ₁ - to C ₆ -haloalkyloxy, C ₁ - to C ₆ -alkylcarbonyl, C ₁ - to C ₆ -alkyloxycarbonyl, C ₃ - to C ₈ -cycloalkyl, phenyl, phenoxy, where the C ₃ - to C ₈ -cycloalkyl, phenyl and phenoxy-

Groups may themselves be partially or completely halogenated and / or may carry one to three of the following groups: hydroxyl, sulfo, cyano, nitro, amino, aminocarbonyl, C ₁ - to C ₆ -alkyl, C ₁ - to C ₆ -haloalkyl, C ₁ - to C ₆ alkyloxy, C ₁ - to C ₆ -Halogenalkyloxy, C ₁ - to C ₆ - alkyloxycarbonyl, C ₁ - to C ₆ alkylcarbonyl; and or

in which one or two of the CH ₂ groups may be replaced by oxygen or NR ⁵ , with at least one group containing one carbon atom between two heteroatoms; for example, 1, 4-butylene, 1, 5-pentylene, 1, 6-hexylene, C _n F _2n-3 Ha with n is 4 to 6, 0 <a <2n;

Butadienylene -CH = CH-CH = CH-, which

^* can carry one to three of the following groups:

Hydroxy, sulfo, cyano, nitro, amino, aminocarbonyl, C ₁ - to C ₆ -alkyl, C ₁ - to C ₆ -haloalkyl, C ₁ - to C ₆ -alkyloxy, C ₁ - to C ₆ -haloalkyloxy, C ₁ - to

Ce-alkylcarbonyl, C ₁ - to C ₆ -alkyloxycarbonyl, C ₃ - to C ₈ -cycloalkyl, phenyl, phenoxy, where the C ₃ - to C ₈ -cycloalkyl, phenyl and phenoxy groups ih¬ rerseits be partially or completely halogenated can and / or carry one to three of the following groups: hydroxyl, sulfo, cyano, nitro, amino, aminocarbonyl, C ₁ - to C ₆ -alkyl, C ₁ - to C ₆ -haloalkyl, C ₁ - to C ₆ -

Alkyloxy, C ₁ - to C ₆ -Halogenalkyloxy, C ₁ - to C ₆ alkyloxycarbonyl, C ₁ - to C ₆ alkylcarbonyl; and or * one or two of the CH groups can be replaced by NR ⁵ , wherein at least one group containing one carbon atom is located between two heteroatoms; for example, butadienylene;

The radicals R ¹ to R ³ in the imidazolium methyl sulfites (I) according to the invention preferably have the following meaning

Hydrogen, fluorine, chlorine, aminocarbonyl, sulfo, cyano;

Cr to C ₂₀ alkyl, C ₁ - to C ₂ o-alkyloxy, d- to _{C2o-alkylcarbonyl,} C ₁ - to C ₂₀ - alkoxycarbonyl, C ₁ - to C ₂ o-acyloxy, C ₁ - to C ₂ o-alkylaminocarbonyl, di (C ₁ - to C ₂₀ -alkyl) -aminocarbonyl, C ₁ - to C ₂ o-alkylamino, di- (C ₁ - to C ₂₀ -alkyl) -amino, where the alkyl Groups may be partially or fully fluorinated or chlorinated; and or

^* can carry one to three of the following groups:

Hydroxy, sulfo, cyano, amino, aminocarbonyl, di (C ₁ - to C ₆ alkyl) amino, C ₁ - to C ₆ alkylcarbonyl, C ₁ - to C ₆ alkyloxycarbonyl, C ₃ - to C ₈ cycloalkyl , Phenyl, phenoxy, where the C ₃ - to C ₈ -cycloalkyl, phenyl and phenoxy groups in turn may be partially or fully fluorinated or chlorinated and / or may carry one to three of the following groups: hydroxy, sulfo, cyano , amino, aminocarbonyl, C ₁ - to C ₆ -alkyl, C ₁ - to C ₆ haloalkyl, C ₁ - to C ₆ - alkyloxy, C ₁ - to C ₆ alkyloxycarbonyl, C ₁ - to C ₆ alkylcarbonyl; and or

in which one to five CH ₂ groups can be replaced by oxygen, with at least one group containing one carbon atom being present between two oxygen heteroatoms;

C ₃ - to Ca-cycloalkyl, this being

^{* may be} partially or completely fluorinated or chlorinated; and / or * may carry one to three of the following groups:

Hydroxy, sulfo, cyano, amino, aminocarbonyl, C ₁ - to C ₆ -alkyl, C ₁ - to C ₆ - halogenoalkyl, C ₁ - to C ₆ alkyloxy, C ₁ - to C ₆ alkyloxycarbonyl, C ₁ - to C ₆ alkylcarbonyl; and or

in which one to three CH ₂ groups can be replaced by oxygen, with at least one group containing one carbon atom being present between two oxygen heteroatoms;

Phenyl, phenoxy, which in turn

* may be partially or completely fluorinated or chlorinated; and / or * may carry one to three of the following groups: Hydroxy, sulfo, cyano, amino, aminocarbonyl, C ₁ to C ₆ alkyl, C ₁ to C ₆ haloalkyl, C ₁ to C ₆ alkyloxy, C ₁ to C ₆ alkyloxycarbonyl, C ₁ to C ₆ alkylcarbonyl.

Particularly preferably, the radicals R ¹ to R ³ in the imidazolium methylsulfiten invention (I) have the following meaning

Hydrogen, fluorine, chlorine;

C ₁ - to C ₆ -alkyl, C ₁ - to C ₆ -alkyloxy, C ₅ - to C ₆ -cycloalkyl, wherein said

Alkyl and cycloalkyl groups

* may be partially or completely fluorinated or chlorinated; and or

in which one to two CH ₂ groups may be replaced by oxygen, where between two oxygen heteroatoms there is at least one group containing a carbon atom;

Phenyl, this being

* may be partially or completely fluorinated or chlorinated; and or

^* may carry one to three of the following groups: C ₁ - to C ₆ -alkyl, C ₁ - to C ₆ -haloalkyl, C ₁ - to C ₆ -alkyloxy.

Examples of the particularly preferred radicals R ¹ to R ³ are: hydrogen, fluorine, chlorine, methyl, ethyl, 1-propyl, 2-propyl, 1-butyl, 2-butyl, 2-methyl-1-propyl (iso) butyl), 2-methyl-2-propyl (tert-butyl), 1-pentyl, 2-pentyl, 3-pentyl, 2-methyl-1-butyl, 3-methyl-1-butyl, 2-methyl-2 butyl, 3-methyl-2-butyl, 2,2-dimethyl-1-propyl, 1-hexyl, 2-hexyl, 3-hexyl, 2-methyl-1-pentyl, 3-methyl-1-pentyl, 4 -Methyl-1-pentyl, 2-methyl-2-pentyl, 3-methyl-2-pentyl, 4-methyl-2-pentyl, 2-methyl-3-pentyl, 3-methyl-3-pentyl, 2.2 Dimethyl-1-butyl, 2,3-dimethyl-1-butyl, 3,3-dimethyl-1-butyl, 2-ethyl-1-butyl, 2,3-dimethyl-2-butyl, 3,3 Dimethyl 2-butyl, methoxymethyl, 2-methoxyethyl, 2-methoxypropyl, 3-methoxypropyl, 4-methoxybutyl, 2-ethoxyethyl, 2-ethoxypropyl, 3-ethoxypropyl,

4-ethoxybutyl, 2-butoxyethyl, 2-isopropoxyethyl, 2-methoxyisopropyl, diethoxymethyl, diethoxyethyl, C _n F _{j 2n + 1)} ^ Ha with n equal to 1 to 6, 0 <a <2n + 1 (for example CF ₃ , C ₂ F ₅ , CH ₂ CH ₂ -C _(n .2) F ₂ (n-2) ₊ i, C ₆ F ₁₃ ), C _n Cl ( ₂ n ₊₁ ) -a) H _a where n is 1 to 6, 0 <a <2n + 1, chloromethyl, 2-chloroethyl, trichloromethyl, 1, 1-dimethyl-2-chloroethyl, 2,2,2-trifluoroethyl, 5-methoxy-3-oxa-pentyl, methoxy, ethoxy, 1-propoxy, 1-butoxy, 1-pentoxy, 1-hexoxy, 2-methoxyethoxy, 2-ethoxyethoxy, 2-propoxyethoxy, 2-butoxyethoxy, 5-methoxy-3-oxa-pentyloxy, 3-methoxypropoxy, 3-ethoxypropoxy, 4-methoxybutoxy, 4-ethoxybutoxy, cyclopentyl, cyclohexyl, 2,3,4,5,6-pentachlorocyclohexyl, CnF ^ n. ^ - aHa where n is 5 to 6, 0 <a <2n-1, C _{n is} CI _{( 2} n- ₁₎ -aH _a with n equal to 5 to 6, 0 <a <n-1, 1, 3-dioxolan-2-yl, 1, 3-dioxan-2-yl, phenyl, 2-methylphenyl (2-ToIyI), 3-methylphenyl (3-ToIyI), 4-methylphenyl (4-ToIyI), 2-ethylphenyl, 3-ethylphenyl, 4-ethylphenyl, 2-methoxyphenyl, 3-methoxyphenyl, 4-methoxyphenyl. Very particular preference is given to the radicals R ¹ to R ³ in the imidazolium methylsulfites (I) according to the invention for hydrogen, methyl, ethyl, 1-propyl, 1-butyl, 1-pentyl, 1-hexyl, 1-octyl, 1-decyl , 1-dodecyl, 1-pentadecyl, and especially for hydrogen, methyl, ethyl, 1-butyl, 1-hexyl, 1-octyl, 1-decyl.

The radical R ⁴ in the imidazolium methylsulfites (I) according to the invention preferably has the following meaning

sulfo;

C ₁ - to C ₂₀ alkyl, this

* may be partially or completely fluorinated or chlorinated; and or

* may carry one to three of the following groups: hydroxyl, sulfo, cyano, amino, aminocarbonyl, di (C ₁ -C ₆ -alkyl) amino, C ₁ -C ₆ -alkylcarbonyl, C ₁ -C ₆ -alkyloxycarbonyl, C ₃ - to C ₈ -cycloalkyl, phenyl, phenoxy, where the C ₃ - to C ₈ -cycloalkyl, phenyl and phenoxy groups in turn may be partially or completely fluorinated or chlorinated and / or one to three of the following groups hydroxyl, sulfo, cyano, amino, aminocarbonyl, C ₁ - to C ₆ -alkyl, C ₁ - to C ₆ -haloalkyl, C ₁ - to C ₆ -

Alkyloxy, C ₁ to C ₆ alkyloxycarbonyl, C ₁ to C ₆ alkylcarbonyl; and or

^* Therein to five CH ₂ groups may be replaced by oxygen, wherein between two oxygen heteroatoms is at least one contains a group containing a carbon atom;

C ₃ to C 6 cycloalkyl, this being

* may be partially or completely fluorinated or chlorinated; and or

* can carry one to three of the following groups:

Hydroxy, sulfo, cyano, amino, aminocarbonyl, C ₁ - to C ₆ -alkyl, C ₁ - to C ₆ - halogenoalkyl, C ₁ - to C ₆ alkyloxy, C ₁ - to C ₆ alkyloxycarbonyl, C ₁ - to C ₆ -

alkylcarbonyl; and or

in which one to three CH ₂ groups may be replaced by oxygen, wherein there is at least one group containing one carbon atom between two oxygen heteroatoms.

Particularly preferably, the radical R ⁴ in the imidazolium methylsulfites (I) according to the invention has the following meaning:

sulfo; C ₁ - to C ₆ -alkyl, C ₅ - to C ₆ -cycloalkyl, wherein said alkyl and cycloalkyl groups

* may be partially or completely fluorinated or chlorinated; and or

in which one to two CH ₂ groups can be replaced by oxygen, wherein at least one group containing one carbon atom is located between two oxygen heteroatoms.

Examples of the particularly preferred radical R ⁴ are: sulfo, methyl, ethyl, 1-propyl, 2-propyl, 1-butyl, 2-butyl, 2-methyl-1-propyl (isobutyl), 2-methyl-2 propyl (tert -butyl), 1-pentyl, 2-pentyl, 3-pentyl, 2-methyl-1-butyl, 3-methyl-1-butyl, 2-methyl-2-butyl, 3-methyl-2- butyl, 2,2-dimethyl-1-propyl, 1-hexyl, 2-hexyl, 3-hexyl, 2-methyl-1-pentyl, 3-methyl-1-pentyl, 4-methyl-1-pentyl, 2 Methyl 2-pentyl, 3-methyl-2-pentyl, 4-methyl-2-pentyl, 2-methyl-3-pentyl, 3-methyl-3-pentyl, 2,2-dimethyl-1-butyl, 2, 3-Dimethyl-1-butyl, 3,3-dimethyl-1-butyl, 2-ethyl-1-butyl, 2,3-dimethyl-2-butyl, 3,3-dimethyl-2-butyl, C _n F _{( 2} n ₊ _i) _a .aH n is 1 to 6, 0 <a <2n + 1 (for example CF _3, C ₂ F _5, CH2CH2-C _(n.2) F ₂ (n-2) ₊ i, C ₆ F ₁₃ ), C _n Cl ₍ 2n ₊₁ ) -a) H _a with n equal to 1 to 6, 0 <a <2n + 1, chloromethyl, 2-chloroethyl, trichloromethyl, 1, 1-dimethyl-2 chloroethyl, 2,2,2-trifluoroethyl, cyclopentyl, cyclohexyl, 2,3,4,5,6-pentachlorocyclohexyl, C _n F _(2n - ₁₎ -aH _a where n is 5 to 6, 0 <a <2n-1, C _{n is} CI _(2n-1 ) -aHa where n is 5 to 6, 0 <a <n-1, 1, 3-dioxolan-2-yl, 1, 3-dioxan-2-yl.

Likewise, the radical R ⁴ in the imidazolium methylsulfites (I) according to the invention preferably has the following meaning

C ₁ - to C _2O -AIKyI, this

^{* may be} partially or completely fluorinated or chlorinated; and or

* can carry one to three of the following groups:

Hydroxy, sulfo, cyano, amino, aminocarbonyl, di (C ₁ - to C ₆ alkyl) amino, C ₁ - to C ₆ alkylcarbonyl, C ₁ - to C ₆ alkyloxycarbonyl, C ₃ - to C ₈ cycloalkyl , Phenyl, phenoxy, where the C ₃ - to C ₈ -cycloalkyl, phenyl and phenoxy groups may in turn be partially or completely fluorinated or chlorinated and / or may carry one to three of the following groups: hydroxy, sulfo, cyano , amino, carbonyl Aminocar¬, Cr to C ₆ alkyl, C ₁ - to C ₆ haloalkyl, C ₁ - to C ₆ alkyloxy, C ₁ - to C ₆ - alkyloxycarbonyl, C ₁ - to C ₆ alkylcarbonyl; and / or * one to five CH ₂ groups may be replaced by oxygen, with at least one group containing one carbon atom between two oxygen heteroatoms being present;

C ₃ - to Ce-cycloalkyl, which may ^{* be} partially or completely fluorinated or chlorinated; and or

* can carry one to three of the following groups: Hydroxy, sulfo, cyano, amino, aminocarbonyl, C ₁ - to C ₆ -alkyl, C ₁ - to C ₆ - halogenoalkyl, C ₁ - to C ₆ alkyloxy, C ₁ - to C ₆ alkyloxycarbonyl, C ₁ - to C ₆ alkylcarbonyl; and or

in which one to three CH ₂ groups can be replaced by oxygen, wherein there is at least one group containing one carbon atom between two oxygen heteroatoms.

C ₁ - to C ₆ -alkyl, C ₅ - to C ₆ -cycloalkyl, wherein said alkyl and cycloalkyl groups

* may be partially or completely fluorinated or chlorinated; and or

^* Therein a may be replaced or two CH ₂ groups are replaced by oxygen, where between two oxygen heteroatoms is at least a carbon-atom is a containing group.

Examples of the particularly preferred radical R ⁴ are: methyl, ethyl, 1-propyl, 2-propyl, 1-butyl, 2-butyl, 2-methyl) -1-propyl (isobutyl), 2-methyl-2-propyl (tert-butyl), 1-pentyl, 2-pentyl, 3-pentyl, 2-methyl-1-butyl, 3-methyl-1-butyl, 2-methyl-2-butyl, 3-methyl-2-butyl , 2,2-dimethyl-1-propyl, 1-hexyl, 2-hexyl, 3-hexyl, 2-methyl-1-pentyl, 3-methyl-1-pentyl, 4-methyl-1-pentyl, 2-methyl 2-pentyl, 3-methyl-2-pentyl, 4-methyl-2-pentyl, 2-methyl-3-pentyl, 3-methyl-3-pentyl, 2,2-dimethyl-1-butyl, 2,3 Dimethyl-1-butyl, 3,3-dimethyl-1-butyl, 2-ethyl-1-butyl, 2,3-dimethyl-2-butyl, 3,3-dimethyl-2-butyl, C _n F ( ₂ n ₊₁₎ -aH _a where n is 1 to 6, 0 <a <2n + 1 (for example, CF ₃ , C ₂ F ₅ , CH ₂ CH ₂ -C ( _n, ₂ ) F _{2 (n -2) +1} , C ₆ F ₁₃ ), C _n Cl ( ₂ n ₊₁ ) -a) H _a with n equal to 1 to 6, 0 <a <2n + 1, chloromethyl, 2-chloroethyl, trichloromethyl , 1, 1-dimethyl-2-chloroethyl, 2,2,2-trifluoroethyl, cyclopentyl, cyclohexyl, 2,3,4,5,6-pentachlorocyclohexyl, C _n F _(2n .i ₎ . _a Ha with n equal to 5 to 6, 0 <a <2n-1, C _n CIi _2n-1) - _a H _a with n equal to 5 to 6, 0 <a <n-1, 1, 3-dioxolane-2 -yl, 1, 3-dioxan-2-yl.

Most preferably, the radical R ⁴ in the imidazolium methyl sulfites (I) according to the invention is methyl, ethyl, 1-propyl, 1-butyl, 1-pentyl, 1-hexyl, 1-octyl, 1-decyl, 1-dodecyl, 1-pentadecyl, and in particular methyl, ethyl, 1-butyl, 1-hexyl, 1-octyl, 1-decyl.

Particularly preferred imidazolium methylsulfites (I) which may be mentioned are: N, N'-dimethylimidazolium methylsulfite, N, N'-ethylmethylimidazolium methylsulfite, N, N '- (1-propyl) methylimidazolium methylsulfite, N, N' - (1-Butyl) methylimidazolium methylsulfite, N, N '- (1-pentyl) methylimidazolium methylsulfite, N, N' - (1-hexyl) methylimidazolium methylsulfite, N, N '- (1-octyl) methylimidazolium methylsulfite, N, N '- (1-decyl) methyl- imidazolium methyl sulfite, N, N '- (1-dodecyl) methyl imidazolium methylsulfite, N, N' - (1-pentadecyl) methyl imidazolium methylsulfite.

The imidazolium methylsulfites (I) according to the invention can be prepared by reacting the corresponding imidazole of the general formula (II)

in which the radicals R ¹ to R ^{4 have} the meaning given in formula (I), be prepared with dimethyl sulfite. For this purpose, both reactants (reactants) together. The type and sequence of addition of the two educts is immaterial in the production process. It is thus possible, for example, to add the imidazole (II) and the dimethyl sulfite successively in any order or in parallel into the reactor. It is also possible to introduce one of the two educts and to drop the other educt over a certain period of time from a few minutes to several hours.

In principle, all reaction apparatuses which are suitable for a reaction in the liquid phase can be used as reaction apparatuses in the production process. These are, in particular, reactors which permit a corresponding mixing of the liquid educts, for example stirred tanks.

The molar ratio of dimethyl sulfite to imidazole (II) in the production process is generally 0.9 to 1.5, preferably 0.9 to 1.2, more preferably 0.9 to 1.1, and most preferably 0.95 until 1, 05.

The reaction between the imidazole (II) and the dimethyl sulfite is carried out at Herstel¬ averaging method generally proceeds at a temperature of 10 to 15O ⁰ C. Erfindungsge¬ Mäss was found, however, that with increasing reaction temperature is generally also the content of the isomeric imidazolium Methanlsulfonat increases, due to thermally induced isomerization of the methyl sulfite anion. In order to obtain particularly pure imidazolium methylsulfite (I) it is therefore preferred to carry out the reaction at a temperature <100 ^° C. The reaction is thus preferably carried out at a temperature of 10 to 100 ^° C., particularly preferably from 20 to 100 ^° C., very particularly preferably from 30 to 90 ^° C. and in particular from 50 to 80 ^° C. The reaction is generally carried out at a pressure of 0.05 to 2 MPa abs, preferably from 0.09 to 0.5 MPa abs, more preferably from 0.09 to 0.2 MPa abs and most preferably from 0.095 to 0.12 MPa abs. The time required for the reaction depends primarily on the chemical nature of the reactant (reactivity of the imidazole (II)) and the chosen reaction temperature. It can be determined, for example, by preliminary experiments in which, for example, the reaction kinetics are determined, the temperature profile of the exothermic reaction is measured and / or the concentrations of the reactants and of the product are determined analytically. In general, the required period of time is in the range of a few minutes to one day, usually of the order of 0.1 to 24 hours, preferably of the order of 0.1 to 10 hours.

The reaction of the imidazole (II) with the dimethyl sulfite forms imidazolium methylsulfite (I) according to the following reaction equation

in stoichiometric amount, where the radicals R ¹ to R ^{4 have} the meaning given in formula (I). In general, the imidazolium methylsulfite (I) is already obtained in a relatively pure form and, depending on the desired purity, can be directly isolated or subjected to a subsequent purification step, as described below.

In the preparation process, it is also possible to use an inorganic or organic solvent, which should be inert under the reaction conditions towards the two educts imidazole (II) and dimethyl sulfite and the product imidazolium methyl sulfite (I). Suitable solvents in principle are, for example, aliphatic, araliphatic or aromatic hydrocarbons, alcohols, ethers, halogenated hydrocarbons, tetrahydrofuran or acetonitrile. If solvents are used, they preferably have a relatively low polarity, in particular to the solvents described in the prior art, such as acetonitrile and alcohol in JP 2001-322,970 or methanol, chloroform and nitrobenzene in DE 228 247, on. This relatively low polarity means that the imidazolium methylsulfite (I) formed during the reaction forms its own solid or liquid phase and thus, for example, unreacted educt or possible by-products preferably remain in the solvent phase.

In this connection, it has been found according to the invention that in the preparation process a particularly pure imidazolium methylsulfite (I) can be obtained in high yield if the reaction is carried out

(i) in the presence of a solvent selected from the group consisting of aromatic hydrocarbons having 6 to 10 carbon atoms, symmetrical or asymmetrical dialkyl ethers having a total of 5 to 10 carbon atoms, cycloalkane having 5 to 8 carbon atoms and C ₅ - to C ₁₀ -alkane; and

(ii) at a temperature of 10 to 100 ^° C

performs.

As aromatic hydrocarbons having 6 to 10 carbon atoms are generally unsubstituted or with C 1 to C ₄ alkyl, -CH = CH-CH = CH-, 1, 4-butylene, -0-CH ₂ -CH ₂ -CH ₂ - substituted benzenes and monohydroxy or monoalkoxy- alkylbenzenes having a number of carbon atoms in the range used. Examples of suitable hydrocarbons having 6 to 10 carbon atoms are benzene, toluene, ethylbenzene, 1-propylbenzene, 2-propylbenzene, 1-butylbenzene, 2-butylbenzene, tert-butylbenzene, xylene (o-, m-, p-) , Methylethylbenzene (o-, m-, p-), diethylbenzene (o-, m-, p-), trimethylbenzene (vic-, sym-, asym-), cresol (o-, m-, p-), ethylphenol (o-, m-, p-), 1, 2,3,4-tetrahydronaphthalene called.

Dialkyl ethers with unbranched or branched alkyl groups are generally used as symmetrical or asymmetrical dialkyl ethers having a total of 5 to 10 carbon atoms, where at least one alkyl group is a C ₃ - to C ₉ -alkyl group. The carbon number of the other alkyl group is given by the total number of carbon atoms mentioned. Examples of suitable symmetrical or asymmetrical dialkyl ethers having a total of 5 to 10 carbon atoms are diisopropyl ether, methyl tert-butyl ether, di-n-butyl ether and diethylene glycol dimethyl ether.

As cycloalkane having 5 to 8 carbon atoms, unsubstituted or substituted with Ci- to Cβ-alkyl cycloalkanes are generally used. Examples of suitable cycloalkanes having 5 to 8 carbon atoms are cyclopentane, methylcyclopentane, cyclohexane, methylcyclohexane, cycloheptane, cyclooctane. As C ₅ - to do-alkane unbranched or branched alkanes are generally used. Examples of suitable C ₅ - to C ₁₀ -alkanes are n-pentane, 2-methylbutane (isopentane), 2,2-dimethylpropane, n-hexane, 2-methylpentane, 3-methylpentane, 2,3-dimethylbutane, 2,2 Dimethylbutane, n-heptane, isomeric heptane, n-octane, isomeric octane, n-nonane, isomeric nonane, n-decane, isomeric decane.

It is of course also possible to use mixtures of different solvents.

The preferred solvent used in the preferred preparation process is preferably toluene, xylene, ethylbenzene, diethylbenzene, methyl tert-butyl ether, cyclohexane, hexane, heptene or octane.

The amount of solvent to be used in the preferred preparation process is generally from 10 to 1000% by weight, preferably from 20 to 500% by weight and more preferably from 20 to 200% by weight, based on the amount of imidazole used. zols (II).

Also in the production process using a solvent, the type and order of addition of the individual reactants and the solvent is immaterial. Thus, it is possible, for example, to give the imidazole (II), the dimethyl sulfite and the solvent in succession in any order or in parallel to the reaction apparatus. It is also possible to add the imidazole (II) and / or the dimethyl sulfite with a part or the total amount of solvent and only then combine both solvent-containing educts. Furthermore, it is also possible to introduce one of the two educts and to drop the other educt over a certain period of time of a few minutes to several hours, at least one of the educts being diluted with the solvent.

If the preparation process in the presence of the preferred solvent selected from the group mentioned aromatic hydrocarbon having 6 to 10 carbon atoms, symmetrical or unsymmetrical dialkyl ethers having a total of 5 to 10 carbon atoms, cycloalkane having 5 to 8 carbon atoms and C ₅ - to Ci _O - Alkan carried out after completion of the mixing of the reaction mixture after the reaction, a phase separation. Depending on the type of reaction apparatus, it may be advantageous to carry out the settling of both phases in this or in a separate settling tank. After settling of both phases, the resulting liquid or solid phase of imidazolium methylsulfite (I) is separated off. In general, the phase of imidazolium methylsulfite (I) is at the bottom and the solvent phase at the top. The separated solvent can generally be recycled and used again as solvent for the reaction mentioned. If necessary, it is advisable to take measures against the enrichment of to take benprodukte in the solvent. Possible measures include, for example, (i) the discharge of a small portion of the solvent and its replacement by fresh solvent or (ii) the distillation of at least a small portion of the solvent followed by recycling.

Depending on the desired purity of the imidazolium methylsulfite (I), it may be advantageous to subsequently subject the resulting crude product, whether from the preparation without the use of a solvent or from the preparation using a solvent, to a purification step. If the phase of the imidazolium methylsulfite (I) is liquid at the working temperature, it can be shaken out with a suitable solvent in which the imidazolium methylsulfite (I) does not dissolve or only dissolves very slightly. Examples of suitable solvents for this purpose are the solvents or esters mentioned as being preferred for the reaction, for example ethyl acetate. If the phase of the imidazolium methylsulfite (I) is solid at the working temperature, it can be washed, for example, with a suitable solvent in which the imidazolium methylsulfite (I) does not dissolve or dissolves only very slightly. Suitable solvents for this purpose are, for example, likewise the solvents or esters mentioned as being preferred for the reaction, for example ethyl acetate. Furthermore, the solid imidazolium methylsulfite (I) can also be recrystallized in a suitable solvent. Suitable solvents for this purpose are solvents in which the imidazolium methylsulfite (I) dissolves, for example alcohol, acetonitrile, tetrahydrofuran or nitrobenzene.

Depending on the further use of the optionally purified imidazolium methylsulfite (I), it is advantageous to dry it beforehand. If drying is carried out, it is preferably carried out in a vacuum that is particularly gentle on the temperature, in order to prevent decomposition of the imidazolium methylsulfite (I) and, in particular, isomerization to the imidazolium methanesulfonate.

The production process can be carried out batchwise, semicontinuously or continuously. In the batchwise reaction, the reactants and optionally the solvent are combined and the reaction is carried out at the desired temperature. After completion of the reaction, the reaction mixture is worked up as described. In the continuous procedure, both starting materials are slowly added to the reaction apparatus for reaction at the desired temperature, wherein, when carried out with a solvent, this is added together with one of the two educts, distributed over both starting materials or separately. The reaction mixture is taken continuously in accordance with the amounts of educts and solvent supplied and worked up as described. The workup itself can also be done continuously. In the case of the semi-continuous variants, at least one of the two educts is added slowly at the desired temperature, the reaction generally being carried out in parallel with the addition he follows. After the desired amount (s) has been added, the reaction mixture is generally allowed to react for a certain time and then worked up as described.

The imidazolium methyl sulfites (I) according to the invention can be used for the preparation of imidazolium salts of various anions. One of the technically relevant anions is the hydrogen sulfite anion. Thus, in one of the preferred uses, the imidazolium methyl sulfites (I) according to the invention are used as starting materials in the preparation of ionic liquids, in which the imidazolium methyl sulfide (I) is reacted with water to liberate methanol and form the imidazolium Hydrogen sulfites reacted. In principle, all reactors which are suitable for a reaction in the liquid phase can be used as reaction apparatuses. These are in particular reactors which allow a corresponding mixing of the liquid educts, for example stirred tank. The molar ratio of water to imidazolium methylsulfite (I) is generally 0.9 to 1.5, preferably 0.95 to 1.2, more preferably 0.95 to 1.1, and most preferably 0, 99 to 1, 05. The reaction is generally carried out at a temperature of 10 to 80 ⁰ C, preferably from 10 to 60 ⁰ C and particularly preferably from 20 to 40 ⁰ C. The pressure is generally 0.05 to 2 MPa abs, preferably 0.09 to 0.5 MPa abs and more preferably 0.095 to 0.12 MPa abs. The time required for the reaction is generally from a few minutes to several hours, preferably from 0.1 to 5 hours, and can be determined, for example, via the course of the reaction (pH, concentration of the methylsulfite anion). After Umset¬ wetting is generally the formed methanol and possibly present excess water in a vacuum at a temperature of 10 to 8O ⁰ C and preferably from 10 to 6O ⁰ C deducted. The product obtained can with solvents in which the imidazolium hydrogen sulfite does not or only very slightly dissolves, such as an aromatic hydrocarbon having 6 to 10 carbon atoms, a sym metric or asymmetric dialkyl ethers having a total of 5 to 10 carbon atoms, a cycloalkane be washed with 5 to 8 carbon atoms or a C ₅ - to C ₁₀ alkane. Further, it is also possible to recrystallize the product in a solvent in which the imidazolium hydrogen sulfite dissolves, such as an alcohol, acetonitrile, tetrahydrofuran or nitrobenzene. The product is generally dried in vacuo.

Further, industrially relevant anions can likewise be prepared from the imidazolium methylsulfites (I) according to the invention in a simple manner. Thus, the imidazolium methyl sulfites (I) according to the invention are used in another of the preferred uses as starting materials in the preparation of ionic liquids in which the imidazolium methylsulfite (I) is reacted with an inorganic or organic protic acid with a pK _a value of 1.8 to 14, measured at 25 ° C. in aqueous solution, with liberation of methanol and sulfur dioxide and Formation of the imidazolium salt of the corresponding partially or fully deprotonated acid anions reaction. The pK _a value of the inorganic or organic protic acid to be used is preferably from 1.8 to 10, particularly preferably from 2 to 10 and very particularly preferably from 3 to 10, measured at 25.degree. C. in aqueous solution. In principle, all reaction apparatuses which are suitable for a reaction in the liquid phase can be used as reaction apparatuses. These are in particular reaction apparatuses which make possible a corresponding mixing of the liquid starting materials, for example stirred tanks. The molar ratio of the inorganic or organic protic acid to imidazolium methylsulfite (I) is generally from 0.9 to 1.5, preferably from 0.95 to 1.1, more preferably from 0.95 to 1.05, and very particularly preferably 0.99 to 1, 02. The reaction is generally carried out at a temperature of 10 to 8O ⁰ C, preferably from 10 to 60 ⁰ C and particularly preferably from 20 to 40 ⁰ C. The pressure is generally 0.05 to 2 MPa abs, preferably 0.09 to 0.5 MPa abs and more preferably 0.095 to 0.12 MPa abs. The time required for the reaction is generally from a few minutes to several hours, preferably from 0.1 to 5 hours, and can be determined, for example, via the course of the reaction (pH, concentration of the methylsulfite anion). After the reaction has taken place, any excess acid present is generally neutralized with a base, for example sodium hydroxide, and the product is subsequently washed with a solvent in which the imidazolium salt does not dissolve, such as, for example, an alcohol, acetonitrile, tetrahydrofuran or nitrobenzene. The product is generally dried in vacuo.

Preference is given to using the imidazolium methylsulfite (I) according to the invention for preparing an imidazolium salt in which the partially or fully deprotonated anion

Fluoride; hexafluorophosphate; hexafluoroarsenate; hexafluoroantimonate; Trifluoroar- genate; Nitrite; Nitrate; Sulfate; Bisulfate; carbonate; hydrogen carbonate; Phosphate; Hydrogen phosphate; Dihydrogen phosphate, vinyl phosphonate, dicyanamide, bis (pentafluoroethyl) phosphinate, tris (pentafluoroethyl) trifluorophosphate, tris (heptafluoropropyl) trifluorophosphate, bis [oxalato (2 -)] borate, bis [salicylato (2 -)] borate, bis [1, 2-benzoldiolato (2 -) - O, O '] borate, tetracyano borate, tetracarbonyl cobaltate;

tetrasubstituted borate of the general formula (Va) [BR ^a R ^b R ^c R ^d ] ^" , wherein R ^a to R ^d independently of one another for fluorine or a carbon-containing organic, saturated or unsaturated, acyclic or cyclic, aliphatic, aromatic or araliphatic radical having 1 to 30 carbon atoms, which contain one or more heteroatoms and / or may be substituted by one or more functional groups or halogen;

organic sulfonate of the general formula (Vb) [R ^e -SO _3] ^", wherein R ^e lenstoff for a Koh¬ comprising organic, saturated or unsaturated, acyclic or cyclic, aliphatic, aromatic or araliphatic radical having 1 to 30 carbon atoms, which may contain one or more heteroatoms and / or may be substituted by one or more functional groups or halogen;

Carboxylate of the general formula (Vc) [R ^f -COO] ^" , wherein R ^{f is} hydrogen or a carbon-containing organic, saturated or unsaturated, acyclic or cyclic, aliphatic, aromatic or araliphatic radical having 1 to 30 carbon atoms, which is one or more Heteroatoms and / or may be substituted by one or more functional groups or halogen;

(Fluoroalkyl) fluorophosphate of the general formula (Vd) [PFx (C _y F _{2Y + I-2} Hz). _6)] ^"where 1 <x <6, 1 <y <8 and O ≤ z <2y + 1 ;

Imide of the general formula (Ve) [R ^g -SO ₂ -N-SO ₂ -R ^h] ^", (Vf) [R-SO ₂ -N-CO-R ^']" or (IVg) [R ¹ ^ CO -N-CO-R ¹ ] ^" , wherein R ⁹ to R ^{1 are} independently hydrogen or a carbon-containing organic, saturated or unsaturated, acycli¬'s or cyclic, aliphatic, aromatic or araliphatic radical having 1 to 30 carbon atoms, which or more heteroatoms and / or may be substituted by one or more functional groups or halogen;

Methide of the general formula (Vh)

SO ₂ -R ^m

Rn-O ₉ S SO ₂ -R °

(Vh),

where R ^m to R ⁰ independently of one another represent hydrogen or a carbon-containing organic, saturated or unsaturated, acyclic or cyclic, aliphatic, aromatic or araliphatic radical having 1 to 30 carbon atoms which contain one or more heteroatoms and / or one or more heteroatoms a plurality of functional groups or halogen may be substituted;

organic sulfate of the general formula (Vi) [R ¹³ O-SO _3] ^", wherein R ^p is a Kohlen¬ material comprising organic, saturated or unsaturated, acyclic or cycli¬ rule, aliphatic, aromatic or araliphatic radical having 1 to 30 carbon - atoms which may contain one or more heteroatoms and / or may be substituted by one or more functional groups or halogen; Halometallat of the general formula (Vj) [M _q Hal _r ] ^{s "} , where M is a metal and Hal for fluorine, chlorine, bromine or iodine, q and r are positive integers and indicate the stoichiometry of the complex and s is a whole positive number and indicates the charge of the complex;

Sulfide, hydrogen sulfide, hydrogen polysulfide of the general formula (Vk) [HS _V ] ^' , polysulfide of the general formula (Vm) [S _v ] ^{2 "} , where v is a whole positive number from 2 to 10, thiolate of the general formula ( Vn) [R ^S S] ^' , where R ^{s is} a carbon-containing organic, saturated or unsaturated, acyclic or cyclic, aliphatic, aromatic or araliphatic radical having 1 to 30 carbon atoms which contain one or more heteroatoms and / or by one or more functional groups or halogen may be substituted;

is.

Heteroatoms are in principle all heteroatoms in question, which are able to formally replace a -CH ₂ -, a -CH =, a C≡ or a = C = group. Ent¬ holds the carbon-containing radical heteroatoms, oxygen, nitrogen, sulfur, phosphorus and silicon are preferred. Preferred groups which may be mentioned are, in particular, -O-, -S-, -SO-, -SO ₂ -, -NR-, -N =, -PR-, -PR ₂ and -SiR ₂ -, where: the radicals R han¬ delt around the remaining part of the carbon-containing radical.

Suitable functional groups are in principle all functional groups which may be bonded to a carbon atom or a heteroatom. Suitable examples include -OH (hydroxy), = 0 (especially as the carbonyl group), -NH ₂ (amino), = NH (imino), -COOH (carboxy), -CONH ₂ (carboxamide) and -CN (cyano) , Fractional groups and heteroatoms can also be directly adjacent, so that combinations of several adjacent atoms, such as -O- (ether), -S- (thioether), -COO- (ester), -CONH- (secondary amide) or -CONR- (tertiary amide), are included,

Halogens are fluorine, chlorine, bromine and iodine.

As carbon-containing organic, saturated or unsaturated, acyclic or cyclic, aliphatic, aromatic or araliphatic radicals having 1 to 30 carbon atoms, the radicals R ^a to R ^d in the tetrasubstituted borate (Va), the radical R ^e in the organic sulfonate (Vb ), the radical R ^f in the case of the carboxylate (Vc), the radicals R ⁹ to R ¹ in the imides (Ve), (Vf) and (Vg), the radicals R ^m to R ⁰ in the case of the methide (Vh) ₁ the radical R ^p in the case of the organic sulfate (Vi) and the radical R ^s in the thiolate (Vn) independently of one another, preferably for C ₁ -C ₃₀ -alkyl and their aryl, hθteroaryl, cycloalkyl, halogen, hydroxy, amino, carboxy, formyl, -O-, -CO-, -CO-O- or - CO-N <substituted Komponen¬ th, such as methyl, ethyl, 1-propyl, 2-propyl, 1-butyl, 2-butyl, 2-methyl-1-propyl (isobutyl), 2-methyl-2-propyl ( tert -butyl), 1-pentyl, 2-pentyl, 3-pentyl, 2-methyl-1-butyl, 3-methyl-1-butyl, 2-methyl-2-butyl, 3-methyl-2-butyl, 2,2-dimethyl-1-propyl, 1-hexyl, 2-hexyl, 3-hexyl, 2-methyl-1-pentyl, 3-methyl-1-pentyl, 4-methyl-1-pentyl, 2-methyl 2-pentyl, 3-methyl-2-pentyl, 4-methyl-2-pentyl, 2-methyl-3-pentyl, 3-methyl-3-pentyl, 2,2-dimethyl-1-butyl, 2,3- Dimethyl-i-butyl, 3,3-dimethyl-1-butyl, 2-ethyl-1-butyl, 2,3-dimethyl-2-butyl, 3,3-dimethyl-2-butyl, heptyl, octyl, nonyl, Decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl,

Octadecyl, nonadecyl, icosyl, henicosyl, docosyl, tricosyl, tetracosyl, pentacosyl, hexacosyl, heptacosyl, octacosyl, nonacosyl, triacontyl, phenylmethyl (benzyl), diphenylmethyl, triphenylmethyl, 2-phenylethyl, 3-phenylpropyl, cyclopentylmethyl, 2-cyclopentylethyl , 3-cyclopentylpropyl, cyclohexylmethyl, 2-cyclohexyl-ethyl, 3-cyclohexylpropyl, methoxy, ethoxy, formyl, acetyl or C _n F _{2 (n.} _a) _{+ (1-b)} H _2a _{+ b} with n <30, 0 ≤ a <n and b = 0 or 1 (for example, CF ₃ , C ₂ F ₅ , CH ₂ CH ₂ -C ( _n-2 ) F ₂ ( _n-2 ) ₊ i, CeFi 3, CsFi ₇ , C 10 F 21, C 12 F 25);

• C ₃ - to Ci ₂ cycloalkyl, and whose aryl, heteroaryl, cycloalkyl, halo, hydroxy, amino, carboxy, formyl, -O-, -CO- or -CO-0-substituted components such as cyclopentyl, 2-methyl-1-cyclopentyl, 3-methyl-1-cyclopentyl, cyclohexyl, 2-methyl-1-cyclohexyl, 3-methyl-1-cyclohexyl, 4-methyl-1-cyclohexyl or CnF ₂ (na) - (ib) H ₂ ab with n <30, 0 <a <n and b = 0 or 1;

C ₂ to C ₃₀ alkenyl and their aryl, heteroaryl, cycloalkyl, halogen, hydroxy, amino, carboxy, formyl, -O-, -CO- or -CO-O-substituted components such as 2-propenyl, 3-butenyl, cis-2-butenyl, trans-2-butenyl or

CπF ₂ ( _n- a) - (ib) H2a-b with n <30, 0 <a <n and b = 0 or 1;

• C ₃ - to C ₂ cycloalkenyl and their aryl-, heteroaryl-, cycloalkyl-, halogen-, hydroxy-, amino-, carboxy-, formyl-, -O-, -CO- or -CO-0-substituted Components ¬ th, such as 3-cyclopentenyl, 2-cyclohexenyl, 3-cyclohexenyl, 2,5-cyclohexadienyl or CnF ₂ (na) -3 (ib) H2a-3b with n <30, 0 <a <n and b = 0 or 1; and

Aryl or heteroaryl having 2 to 30 carbon atoms and their alkyl, aryl, heteroaryl, cycloalkyl, halogen, hydroxy, amino, carboxy, formyl, -O-, -CO- or -CO 0-substituted components such as phenyl, 2-methyl-phenyl (2-tolyl), 3-methyl-phenyl (3-ToIyI), 4-methyl-phenyl, 2-ethyl-phenyl, 3-ethyl-phenyl , 4-ethyl-phenyl, 2,3-dimethyl-phenyl, 2,4-dimethyl-phenyl, 2,5-dimethyl-phenyl, 2,6-dimethyl-phenyl, 3,4-dimethyl-phenyl, 3,5 Dimethylphenyl, 4-phenylphenyl, 1-naphthyl, 2-naphthyl, 1-pyrrolyl, 2-pyrrolyl, 3-pyrrolyl, 2-pyridinyl, 3-pyridinyl, 4-pyridinyl, or C ₆ F (5, _a ) H _a with 0 <a <5.

Is When the anion is a tetra-substituted borate (Va) [BR ^a R ^b R c R ^d], ^"so, in this preferred all four groups R ^a to R ^d are the same, which preferably Fluorine, trifluoromethyl, pentafluoroethyl, phenyl, 3,5-bis (trifluoromethyl) phenyl. Particularly preferred tetrasubstituted borates (Va) are tetraflouroborate, tetraphenylborate and tetra [3,5-bis (trifluoromethyl) phenyl] borate.

If the anion is an organic sulfonate (Vb) [R ⁸ -SO ₃ ] ^' , the radical R ^{e is} preferably methyl, trifluoromethyl, pentafluoroethyl, p-tolyl or C ₉ F ₁₉ . Particularly preferred organic sulfonates (Vb) are trifluoromethanesulfonate (triflate), methanesulfonate, p-tolylsulfonate, nonadecafluorononanesulfonate (nonaflate), dimethlylene glycol monomethyl ether sulfate and octyl sulfate.

If the anion is a carboxylate (Vc) [R ^f -COO] ^' , the radical R ^{f is} preferably hydrogen, trifluoromethyl, pentafluoroethyl, phenyl, hydroxyphenylmethyl, trichloromethyl, dichloromethyl, chloromethyl, trifluoromethyl , Difluoromethyl, fluoromethyl, ethenyl (vinyl), 2-propenyl, -CH = CH-COO ^" , cis-8-heptadecenyl, -CH ₂ -C (OH) (COOH) -CH ₂ -COO ^" or unbranched or branched C ₁ - to C ₁₈ -alkyl, such as, for example, methyl, ethyl, 1-propyl, 2-propyl, 1-butyl, 2-butyl, 2-methyl-1-propyl (isobutyl), 2-methyl-2-propyl (tert-butyl), 1-pentyl, 2-pentyl, 3-pentyl, 2-methyl-1-butyl, 3-methyl-1-butyl, 2-methyl-2-butyl, 3-methyl-2-butyl , 2,2-dimethyl-1-propyl, 1-hexyl, 2-hexyl, 3-hexyl, 2-methyl-1-pentyl, 3-methyl-1-pentyl, 4-methyl-1-pentyl, 2-methyl 2-pentyl, 3-methyl-2-pentyl, 4-methyl-2-pentyl, 2-methyl-3-pentyl, 3-methyl-3-pentyl, 2,2-dimethyl-1-butyl, 2,3 Dimethyl-1-butyl, 3,3-dimethyl-1-butyl, 2-ethyl-1-butyl, 2,3-dimethyl-2-butyl, 3,3-dimethyl-2 butyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, heptadecyl. Particularly preferred carboxylates (Vc) are formate, acetate, propionate, butyrate, valerate, benzoate, mandelate, trichloroacetate, dichloroacetate, chloroacetate, trifluoroacetate, difluoroacetate, fluoroacetate.

Are If it is When the anion is a (fluoroalkyl) fluorophosphate (Vd) [PF _x (C _y F ₂ y ₊₁ -ZH _z) ₆ .χ] ^", such is preferably 0. Particularly preferred (fluoroalkyl) fluorophosphates (Vd ) in which z = 0, x = 3 and 1 <y <4, specifically [PF ₃ (CFg) ₃ ] ^" , [PF ₃ (C ₂ Fs) ₃ ] ^" , [PF ₃ (C ₃ F ₇ ) ₃ ] ^' and [PF ₃ (C ₄ F ₇ ) ₃ ] ^" .

Wherever the anion is an imide (Ve) [R ^g -SO ₂ -N-SO ₂ -R ^h] ^", (Vf) [R ⁱ -SO ₂ -N-CO-R ^']" or (Vg) [R 1 CO-N-CO-R ¹ ] ^" , the radicals R ⁹ to R ¹ independently of one another preferably represent trifluoromethyl, pentafluoroethyl, phenyl, trichloromethyl, dichloromethyl, chloromethyl, trifluoromethyl, difluoromethyl, fluoromethyl or unbranched or branched C ₁ - to C ₁₂ -alkyl, such as, for example, methyl, ethyl, 1-propyl, 2-propyl, 1-butyl, 2-butyl, 2-methyl-1-propyl (isobutyl), 2-methyl-2-one propyl (tert -butyl), 1-pentyl, 2-pentyl, 3-pentyI, 2-methyl-1-butyl, 3-methyl-1-butyl, 2-methyl-2-butyl, 3-methyl-2- butyl, 2,2-dimethyl-1-propyl, 1-hexyl, 2-hexyl, 3-hexyl, 2-methyl-1-pentyl, 3-methyl-1-pentyl, 4-methyl-1-pentyl, 2- Methyl 2-pentyl, 3-methyl-2-pentyl, 4-methyl-2-pentyl, 2-methyl-3-pentyl, 3-methyl-3-pentyl, 2,2-dimethyl-1-butyl, 2, 3-dimethyl-butyl, 3,3-dimethyl-1-butyl, 2-ethyl-1-butyl, 2,3-dimethyl-2-butyl, 3,3-dimethyl-2-butyl, heptyl, Octyl, nonyl, decyl, undecyl or dodecyl. Particularly preferred imides (Ve), (Vf) and (Vg) are [F ₃ C-SO ₂ -N-SO ₂ -CF _3] ^"(bis (trifluoromethylsulfonyl) imide), [F ₅ C ₂ -SO ₂ -N -SO ₂ -C ₂ F _5] ^"(bis (pentafluoroethylsulfonyl) imide), [F ₃ C-SO ₂ -N-CO-CF _3] ^', [F ₃ C-CO-N-CO-CF _^3]" and those in which the radicals R ⁹ to R ¹ independently of one another are methyl, ethyl, propyl, butyl, phenyl, trichloromethyl, dichloromethyl, chloromethyl, trifluoromethyl, difluoromethyl or fluoromethyl.

Is the anion a methide (Vh)?

SO ₂ -R ^m

Rn-O ₂ S ^' ^" SO ₂ -R ⁰

(Vh),

Thus, the radicals R ^m to R ⁰ independently of one another are preferably trifluoromethyl, pentafluoroethyl, phenyl, trichloromethyl, dichloromethyl, chloromethyl, trifluoromethyl, difluoromethyl, fluoromethyl or straight-chain or branched C _r to C ₁₂ -alkyl, such as, for example, methyl, ethyl, Propyl, 2-propyl, 1-butyl, 2-butyl, 2-methyl-1-propyl (isobutyl), 2-methyl-2-propyl (tert-butyl), 1-pentyl, 2-pentyl, 3-pentyl , 2-methyl-1-butyl, 3-methyl-1-butyl, 2-methyl-2-butyl, 3-methyl-2-butyl, 2,2-dimethyl-1-propyl, 1-hexyl, 2-hexyl , 3-hexyl, 2-methyl-1-pentyl, 3-methyl-1-pentyl, 4-methyl-1-pentyl, 2-methyl-2-pentyl, 3-methyl-2-pentyl, 4-methyl-2 pentyl, 2-methyl-3-pentyl, 3-methyl-3-pentyl, 2,2-dimethyl-1-butyl, 2,3-dimethyl-1-butyl, 3,3-dimethyl-1-butyl, 2 Ethyl-1-butyl, 2,3-dimethyl-2-butyl, 3,3-dimethyl-2-butyl, heptyl, octyl, nonyl, decyl, undecyl or dodecyl. Methides (Vh) Particularly preferred are [(F ₃ C-SO ₂₎ ₃ C] ^"(tris (trifluoromethyl sulfonyl) methide), [(C ₅ F ₂ -SO ₂₎ ₃ ^C]" (bis (pentafluoroethylsulfonyl) methide ) and those in which the radicals R ^m to R ⁰ independently of one another are methyl, ethyl, propyl, butyl, phenyl, trichloromethyl, dichloromethyl, chloromethyl, trifluoromethyl, difluoromethyl or fluoromethyl.

If the anion is an organic sulfate (Vi) [R ^P O-SO ₃ ] ^' , the radical R ^{p is} preferably a branched or unbranched C ₁ - to C ₃₀ -alkyl radical. Particularly preferred organic sulfates (Vi) are methyl sulfate, ethyl sulfate, propyl sulfate, butyl sulfate, pentyl sulfate, hexyl sulfate, heptyl sulfate or octyl sulfate.

If it is, stands When the anion is a halometalate (Vj) [M _q Hal _r] ^{s "as} M preferably represents aluminum, zinc, iron, Cobald, antimony or tin. Hal is preferably chlorine or bromine, and very particularly preferably represents chlorine , q is preferably 1, 2 or 3 and r and s are given according to the stoichiometry and charge of the metal ion. If the anion is thiolate (Vn) [R ^S S] ^' , the radical R ^{s is} preferably a branched or unbranched C ₁ - to C ₃₀ -alklyl radical. Particularly preferred thiolates (Vn) are methylsulfide, ethylsulfide, n-propylsulfide, n-butylsulfide, n-pentylsulfide, n-hexylsulfide, n-heptylsulfide, n-octylsulfide or n-dodecylsulfide.

Very particular preference is given to using the imidazolium methylsulfite (I) according to the invention for the preparation of an imidazolium salt in which the partially or fully deprotonated anion tetrafluoroborate, hexafluorophosphate, trifluoromethanesulfonate, methanesulfonate, formate, acetate, mandelate, nitrate, nitrite, trifluoroacetate, Sulfate, hydrogen sulfate, methylsulfate, ethylsulfate, propylsulfate, butylsulfate, pentylsulfate, hexylsulfate, heptylsulfate, octylsulfate, phosphate, dihydrogenphosphate, hydrogenphosphate, propionate, tetrachloroaluminate, Al ₂ Cl ₇ ^' , chlorozincate, chloroferrate, bis (trifluoromethylsulfonyl) imide, Bis (pentafluoroethylsulfonyl) imide, tris (trifluoromethylsulfonyl) methide, bis (pentafluoroethylsulfonyl) methide, p-tolylsulfonate, bis [salicylato (2 -)] borate, tetracarbonylcobaltate, dimethylenglycolmonomethylethersulfate, octylsulfate, oleate, stearate, acrylate, methacrylate, Maleate, hydrogen citrate, vinyl phosphonate, bis (pentafluoroethyl) phosphinate, bis [oxalato (2 -)] borate, bis [1,2-benzenediol ato (2 -) - O, O ¹ ] borate, dicyanamide, tris (pentafluoroethyl) trifluorophosphate, tris (heptafluoropropyl) trifluorophosphate, tetracyano borate or chlorocobaltate.

The imidazolium methyl sulfites (I) according to the invention are important starting compounds for the preparation of ionic, 1,3-disubstituted imidazolium-based liquids. They are simple, without the use of toxic alkylating agents, using a readily available, readily available, and industrially readily available reactive alkylating agent, can be displayed in high yield and high purity, the high purity can be achieved without extensive purification. The imidazolium methylsulfites (I) according to the invention can be converted easily and flexibly into the desired ionic, 1,3-disubstituted imidazolium-based liquid with the desired anion, and these can likewise be produced in high yield and high purity, even without separate, complicated purification ,

The particular advantage of the imidazolium methylsulfites (I) according to the invention is that, when they are reacted with water or an inorganic or organic protic acid to prepare the desired ionic, 1,3-disubstituted imidazolium-based liquids, the methylsulfite anion is readily and completely absorbed Formation of volatile methanol (in the reaction with water to the hydrogen sulfite) or to form volatile methanol and volatile sulfur dioxide (when reacted with an inorganic or organic protic acid) can be removed.

The desired ionic liquids which can be prepared from the imidazolium methylsulfites (I) according to the invention are therefore also suitable without problems for use in the electronics industry. Examples

Example 1 (N, N'-butylmethylimidazolium methylsulfite)

21.11 g (0.192 mol) of dimethyl sulfite were initially charged in 100 ml of toluene and a solution of 23.8 g (0.192 mol) of N-butylimidazole in 25 ml of toluene was added. The solution was stirred at 60 ^° C. for 15 hours. During the reaction, a second liquid phase was formed by the resulting N, N'-butylmethylimidazolium methylsulfite. Upon completion of the stirring, both phases separated. The lower, N, N'-butyl-methylimidazolium-methyl sulfite-containing phase was separated and extracted by shaking twice with ethyl acetate. N, N'-butyl-methylimidazolium methylsulfite was then dried in vacuo at 0.3 kPa (3 mbar) at 40 ⁰ C. The weight was 37.5 g, corresponding to 83% overall theoretical yield (N, N'-butylmethylimidazolium methylsulfite and methanesulfonate).

The resulting liquid product was analyzed by NMR spectroscopy and identified as N ₁ N ¹ -butyl-methylimidazolium methyl sulfite:

[1 H-NMR, 400 MHz], D ₂ O: 0.9 ppm (t-3H); 1.3 ppm (m - 2H); 1.8 ppm (m - 2H); 2.8 ppm (s - 3H - CH ₃ SO ₃ ^' ); 3.4 ppm (s - 3H); 3.8 ppm (s - 3H); 4.2 ppm (t - 2H); 7.4 ppm (d - 2H); 8.7 ppm (s -1 H).

A quantitative evaluation of the NMR spectrum showed from the signal ratio 2.8 ppm (3H-methanesulfonate): 3.8 ppm (3H-methyl group on imidazolium nitrogen) that the proportion of methanesulfonate formed was below the detection limit. This is 3 mol%. The purity of the N.N'-butyl-methylimidazolium methylsulfite was thus> 97%.

Example 2 (Synthesis of N, N'-butylmethylimidazolium acetate starting from N ₁ N'-butylmethylimidazolium methylsulfite)

49.3 g (0.21 mol) of N, N'-butyl-methylimidazolium methylsulfite, which was prepared by the preparation of Example 1, were initially charged at room temperature and, while stirring, 13 g (0.21 mol) of acetic acid were slowly added dropwise. The reaction mixture was carefully placed between 40 and 65 ⁰ C under a vacuum of 50 to 0.2 kPa (500 to 2 mbar), wherein formed methanol were distilled off. After the formation of methanol and distilling off was complete, the reaction mixture was heated to 140 ⁰ C er¬, and (3 mbar) removed under vacuum to 0.3 kPa of sulfur dioxide. The latter was collected in a cold trap. The yield of reaction product was 37.2 g, corresponding to 90% theoretical total yield. The resulting liquid product was analyzed by NMR spectroscopy and identified as N.N'-butyl-methylimidazolium acetate:

[1 H-NMR, 400 MHz], D ₂ O: 0.9 ppm (t-3H); 1.3 ppm (m - 2H); 1.8 ppm (m - 2H); 1, 9 ppm (s - 3H CH ₃ COOO, 3.4 ppm (s - 3H), 3.8 ppm (s - 3H), 4.2 ppm (t - 2H), 7.4 ppm (d - 2H ); 8.7 ppm (s - 1H)

Example 2 shows that from the novel N, N'-butyl-methylimidazolium methylsulfite in a simple reaction with acetic acid, the desired ionic liquid N, N'-butyl-methylimidazolium acetate can be prepared in high yield and high purity.

Claims

claims

1. Imidazolium methyl sulfites of the general formula (I)

in which the radicals independently of one another have the following meanings:

R ¹ to R ³ :

Hydrogen, halogen, hydroxy, amino, aminocarbonyl, sulfo, cyano, nitro;

C ₁ - to C ₂₀ -alkyl, C ₂ - to C ₂ o-alkenyl, C ₂ - to C ₂ o-alkynyl, C ₁ - to C ₂₀ -alkyl-oxy, C ₂ - to C ₂₀ -alkenyloxy, C ₂ - to C ₂ o-alkynyloxy, C ₁ - to C ₂₀ -alkylcarbonyl, C ₁ - to C ₂₀ -alkyloxycarbonyl, C ₁ - to C ₂₀ -acyloxy, C ₁ - to C ₂₀ -alkylamino-carbonyl, di - (C ₁ - to C ₂₀ -alkyl) aminocarbonyl, C ₁ - to C ₂₀ -alkylamino, di- (C ₁ - to C ₂₀ -alkyl) amino, C ₁ - to C ₂ o-alkylsulfonyl, wherein said alkyl , Alkenyl and alkynyl groups

* may be partially or completely halogenated; and or

* can carry one to three of the following groups:

Hydroxyl, sulfo, cyano, nitro, amino, aminocarbonyl, di (C ₁ - to C ₆ -alkyl) amino, C ₁ - to C ₆ -alkylcarbonyl, C ₁ - to C ₆ -alkyloxycarbonyl, C ₃ - to Cβ- Cycloalkyl, phenyl, phenoxy, where the C ₃ - to C ₈ -cycloalkyl, phenyl and phenoxy groups may in turn be partially or completely halogenated and / or may carry one to three of the following groups: hydroxyl, sulfo, cyano, nitro, amino, aminocarbonyl, C ₁ - to C ₆ -alkyl, C ₁ - to C ₆ haloalkyl, C ₁ - to C ₆ alkyloxy, C ₁ - to C ₆ -Halogenalkyloxy, C ₁ - to Ces alkyloxycarbonyl, C ₁ - to C ₆ alkylcarbonyl; and or

in which one to five CH ₂ groups can be replaced by oxygen, wherein at least one group containing one carbon atom is located between two oxygen heteroatoms;

C ₃ - to Cs-cycloalkyl, this being

* may be partially or completely halogenated; and or

* can carry one to three of the following groups: Hydroxyl, sulfo, cyano, nitro, amino, aminocarbonyl, C ₁ - to C ₆ -alkyl, C ₁ - to cerium haloalkyl, C ₁ - to C ₆ -alkyloxy, C ₁ - to C ₆ -haloalkyloxy, C ₁ - to C ₆ - Alkyloxycarbonyl, C ₁ to C ₆ alkylcarbonyl; and or

in which one to three d-fe groups can be replaced by oxygen, in which there is at least one group containing a carbon atom between two oxygen heteroatoms;

Phenyl, phenoxy, which in turn

* may be partially or completely halogenated; and / or ^* may carry one to three of the following groups:

Hydroxy, sulfo, cyano, nitro, amino, aminocarbonyl, C ₁ - to C ₆ -alkyl, C ₁ - to C ₆ -haloalkyl, C ₁ - to C ₆ -alkyloxy, C ₁ - to C ₆ -haloalkyloxy, C ₁ - to C ₆ -alkyloxycarbonyl, C ₁ - to C ₆ -alkylcarbonyl;

R ⁴ :

sulfo;

C ₁ - to C _2O -AlkVl, C ₂ - to C ₂ o-alkenyl, C ₂ - to C ₂₀ -alkynyl, wherein the genann¬ th alkyl, alkenyl and alkynyl groups * may be partially or completely halogenated; and or

* can carry one to three of the following groups:

Hydroxy, sulfo, cyano, nitro, amino, aminocarbonyl, di (C ₁ - to C ₆ - alkyl) amino, C ₁ - to C ₆ alkylcarbonyl, C ₁ - to C ₆ alkyloxycarbonyl, C ₃ - to C ₈ -Cycloalkyl, phenyl, phenoxy, wherein the C ₃ - to C ₈ -cycloalkyl, phenyl and phenoxy groups in turn may be partially or fully halogenated and / or may carry one to three of the following groups: hydroxy, sulfo, cyano, nitro , amino, aminocarbonyl, C ₁ - to C ₆ -alkyl, C ₁ - to C ₆ haloalkyl, C ₁ - to C ₆ alkyloxy, C ₁ - to C ₆ -Halogenalkyloxy, C ₁ - to Ce alkyloxycarbonyl, C ₁ to C ₆ alkylcarbonyl; and / or ^* one to five CH ₂ groups may be replaced by oxygen, wherein at least one group containing one carbon atom is present between two oxygen heteroatoms;

C ₃ - to C ₈ -cycloalkyl, where this * may be partially or completely halogenated; and or

* can carry one to three of the following groups:

Hydroxy, sulfo, cyano, nitro, amino, aminocarbonyl, C ₁ - to C ₆ -alkyl, C ₁ - to C ₆ -haloalkyl, C ₁ - to C ₆ -alkyloxy, C ₁ - to C ₆ -haloalkyloxy, C ₁ - to C ₆ -alkyloxycarbonyl, C ₁ - to C ₆ -alkylcarbonyl; and / or * in which one to three CH ₂ groups may be replaced by oxygen, wherein at least one group containing one carbon atom is present between two oxygen heteroatoms; Phenyl, this being

* may be partially or completely halogenated; and or

* can carry one to three of the following groups:

Hydroxy, sulfo, cyano, nitro, amino, aminocarbonyl, C ₁ - to C ₆ -alkyl, C ₁ - to Ce-haloalkyl, C ₁ - to C ₆ -alkyloxy, C ₁ - to C ₆ -haloalkyloxy, C ₁ - to

Ce-alkyloxycarbonyl, C ₁ to C ₆ alkylcarbonyl;

or

Alkylene - (CH ₂ ) _n - with n = 4, 5 or 6, this being

^{* may be} partially or completely halogenated; and or

^* may carry one to three of the following groups: hydroxy, sulfo, cyano, nitro, amino, aminocarbonyl, C ₁ - to C ₆ -alkyl, C ₁ - to C ₆ -haloalkyl, C ₁ - to C ₆ -alkyloxy, C ₁ - to Cβ-haloalkyloxy, C ₁ - to Ce-alkylcarbonyl, C ₁ - to C ₆ -alkyloxycarbonyl, C ₃ - to C ₈ -cycloalkyl, phenyl, phenoxy, where the C ₃ - to C ₈ - Cycloalkyl, phenyl and phenoxy groups in turn may be partially or completely halogenated and / or may carry one to three of the following groups:

^* Is one or two of the CH ₂ -G 'groups by oxygen or NR ⁵ may be replaced, wherein at least one between two hetero atoms,

Contains carbon atom-containing group;

Butadienylene -CH = CH-CH = CH-, which

^* may carry one to three of the following groups: hydroxy, sulfo, cyano, nitro, amino, aminocarbonyl, C ₁ - to C ₆ -alkyl, C ₁ - to Ce-haloalkyl, C ₁ - to C ₆ -alkyloxy, C ₁ - to C ₆ -haloalkyloxy, C ₁ - to C ₆ -alkylcarbonyl, C ₁ - to C ₆ -alkyloxycarbonyl, C ₃ - to C ₈ -cycloalkyl, phenyl, phenoxy, where the C ₃ - to C ₈ -Cycloalkyl, phenyl and phenoxy groups in turn may be partially or fully halogenated and / or may carry one to three of the following groups:

^* one or two of the CH groups can be replaced by NR ⁵ , with at least one group containing one carbon atom between two heteroatoms; R ^5:

Hydrogen, C ₁ - to C ₆ -alkyl, Cr to C ₆ -haloalkyl or C ₁ - to C ₆ -alkyloxy.

2. Imidazolium methylsulfite of the general formula (I) according to claim 1, in which the radicals R ¹ to R ³ independently of one another have the following meanings:

Hydrogen, fluorine, chlorine, aminocarbonyl, sulfo, cyano;

C ₁ to C ₂₀ alkyl, C ₁ to C ₂₀ alkyloxy, C ₁ to C ₂₀ alkylcarbonyl, C ₁ to C ₂₀ alkyloxycarbonyl, C ₁ to C ₂₀ acyloxy, C ₁ to C _20- alkylaminocarbonyl, di (C ₁ - bis

C ₂₀ alkyl) aminocarbonyl, C ₁ - to C ₂ o-alkylamino, di- (C ₁ - to C ₂₀ -alkyl) amino, wherein said alkyl groups

^{* may be} partially or completely fluorinated or chlorinated; and or

^* may carry one to three of the following groups: hydroxy, sulfo, cyano, amino, aminocarbonyl, di (C ₁ - to C ₆ -alkyl) amino,

C ₁ - to Ce-alkylcarbonyl, C ₁ - to C ₆ -alkyloxycarbonyl, C ₃ - to C ₈ -cycloalkyl, phenyl, phenoxy, where the C ₃ - to C ₈ -cycloalkyl, phenyl and phenoxy groups in turn partially or be fully fluorinated or chlorinated and / or may carry one to three of the following groups: hydroxyl, sulfo, cyano, amino, aminocarbonyl, C ₁ - to C ₆ -alkyl, C ₁ - to C ₆ -haloalkyl, C ₁ - to C ₆ -alkyloxy, C ₁ - to C ₆ -alkyl-oxycarbonyl, C ₁ - to Ce-alkylcarbonyl; and or

^* Therein a may be replaced to five CH ₂ groups are replaced by oxygen, it being possible for between two oxygen heteroatoms is at least one, a carbonic group-containing lenstoffatom located;

C ₃ to C ₈ cycloalkyl, this being

^{* may be} partially or completely fluorinated or chlorinated; and or

^* may carry one to three of the following groups: hydroxy, sulfo, cyano, amino, aminocarbonyl, C ₁ - to C ₆ -alkyl, C ₁ - to C ₆ -

Haloalkyl, C ₁ - to C ₆ -alkyloxy, C ₁ - to C ₆ -alkyloxycarbonyl, C ₁ - to C ₆ -alkylcarbonyl; and or

^* Therein a may be replaced one to three CH ₂ groups are replaced by oxygen, it being possible for between two oxygen heteroatoms is at least one, a carbonic group-containing lenstoffatom located;

Phenyl, phenoxy, which in turn

^{* may be} partially or completely fluorinated or chlorinated; and or

* may carry one to three of the following groups: hydroxyl, sulfo, cyano, amino, aminocarbonyl, C ₁ - to C ₆ -alkyl, C ₁ - to C ₆ -

Haloalkyl, C ₁ - to C ₆ alkyloxy, C ₁ - to C ₆ alkyloxycarbonyl, C ₁ - to Ce alkylcarbonyl;

3. Imidazolium methylsulfite of the general formula (I) according to claim 2, in which the radicals R ¹ to R ³ independently of one another have the following meanings:

Hydrogen, fluorine, chlorine;

C ₁ - to C ₆ -alkyl, C ₁ - to C ₆ -alkyloxy, C ₅ - to C ₆ -cycloalkyl, wherein said alkyl and cycloalkyl groups

* may be partially or completely fluorinated or chlorinated; and / or * in which one to two CH ₂ groups can be replaced by oxygen, wherein at least one group containing one carbon atom is present between two oxygen heteroatoms;

Phenyl, which may be partially or completely fluorinated or chlorinated; and or

^* can carry one to three of the following groups:

C ₁ - to C ₆ -AlkVl, C ₁ - to C ₆ haloalkyl, C ₁ - to C ₆ alkyloxy.

4. Imidazolium methylsulfite of the general formula (I) according to claim 3, in which the radicals R ¹ to R ³ independently of one another have the following meanings: hydrogen, methyl, ethyl, 1-propyl, 1-butyl, 1-pentyl, 1-hexyl, 1-octyl, 1-decyl, 1-dodecyl, 1-pentadecyl.

5. Imidazolium methylsulfite of the general formula (I) according to claims 1 to 4, in which the radical R ^{4 has the} following meaning:

sulfo;

C ₁ to C ₂₀ alkyl, which may be partially or completely fluorinated or chlorinated; and or

* can carry one to three of the following groups:

Hydroxy, sulfo, cyano, amino, aminocarbonyl, di- (C ₁ - to C ₆ -alkyl) -amino, C ₁ - to Ce-alkylcarbonyl, C ₁ - to C ₆ -alkyloxycarbonyl, C ₃ - to C ₈ -cycloalkyl , Phenyl, phenoxy, where the C ₃ - to C ₈ -cycloalkyl, phenyl and phenoxy groups may in turn be partially or fully fluorinated or chlorinated and / or may carry one to three of the following groups: hydroxy, sulfo, cyano , Amino, aminocarbonyl, C ₁ - to C ₆ -alkyl, C ₁ - to C ₆ -haloalkyl, C ₁ - to C ₆ -alkyloxy, C ₁ - to C ₆ -alkyl-oxycarbonyl, C ₁ - to C _6- alkyl-arbonyl; and / or * one to five CH ₂ groups may be replaced by oxygen, wherein at least one group containing one carbon atom is present between two oxygen heteroatoms; C ₃ - to Cs-cycloalkyl, this being

* may be partially or completely fluorinated or chlorinated; and or

* may carry one to three of the following groups: hydroxy, sulfo, cyano, amino, aminocarbonyl, C ₁ - to C ₆ -alkyl, C ₁ - to C ₆ -

^* Therein a may be replaced one to three CH ₂ groups are replaced by oxygen, it being possible for between two oxygen heteroatoms is at least one, a coal is lenstoffatom containing group.

6. Imidazolium methylsulfites of the general formula (I) according to claim 5, in which the radical R ^{4 has the} following meanings:

sulfo;

C ₁ to C ₆ alkyl, C ₅ to C ₆ cycloalkyl, said alkyl and cycloalkyl groups

^{* may be} partially or completely fluorinated or chlorinated; and / or ^* one or two CH ₂ groups may be replaced by oxygen, where between two oxygen heteroatoms there is at least one group containing a carbon atom.

7. Imidazolium methylsulfite of the general formula (I) according to claim 6, in which the radical R ^{4 has the} following meaning: methyl, ethyl, 1-propyl, 1-butyl, 1-pentyl,

1-hexyl, 1-octyl, 1-decyl, 1-dodecyl, 1-pentadecyl.

8. N, N'-dimethylimidazolium methylsulfite, N, N'-ethylmethylimidazolium methylsulfite, N, N '- (1-propyl) methylimidazolium methylsulfite, N, N' - (1-butyl) methylimidazolium methylsulfite, N, N '- (1-Pentyl) methylimidazolium methylsulfite, N, N' - (1-hexyl) methylimidazolium methylsulfite, N, N '- (1-octylmethylimidazolium methylsulfite, N, N' - (1-decyl) methylimidazolium methyl sulfite, N, N '- (1-dodecyl) methyl imidazolium methylsulfite, N, N' - (1-pentadecyl) methyl imidazolium methylsulfite.

9. A process for the preparation of imidazolium methylsulfites of the general formula (I), which comprises reacting the corresponding imidazole of the all-α-chelated F Formell ((WII))

(II) in which the radicals R ¹ to R ^{4 have} the meaning given in formula (I), reacted with dimethyl sulfite.

10. The method according to claim 9, characterized in that the reaction

(i) in the presence of a solvent selected from the group aromatic hydrocarbon having 6 to 10 carbon atoms, symmetrical or unsymmetrical dialkyl ethers having a total of 5 to 10 carbon atoms, cycloalkane having 5 to 8 carbon atoms and C ₅ - to Cio-alkane; and

(ii) at a temperature of 10 to 100 ^° C

performs.

11. Use of imidazolium methylsulf ite of the general formula (I) as Aus¬ gangsstoffe in the production of ionic liquids, characterized gekenn¬ characterized in that the imidazolium methylsulfit (I) with water with release of methanol and formation of the Imidazolium-hydrogensulfits.

12. Use of the imidazolium methylsulfites of the general formula (I) as starting materials in the preparation of ionic liquids, characterized gekenn¬ characterized in that the imidazolium methylsulfite (I) with an inorganic or organic protic acid having a pK _a value from 1, 8 to 14, measured at 25 ° C in aqueous solution, with liberation of methanol and sulfur dioxide and formation of the imidazolium salt of the corresponding partially or fully deprotonated acid anions reacted.

13. Use according to claim 12, characterized in that an imidazolium salt is prepared in which the partially or fully deprotonated anion tetrafluoroborate, hexafluorophosphate, trifluoromethanesulfonate, methanesulfonate, formate, acetate, mandelate, nitrate, nitrite, trifluoroacetate, Sulfate, hydrogensulfate, methylsulfate, ethylsulfate, propylsulfate, butylsulfate, pentylsulfate, hexylsulfate, heptylsulfate, octylsulfate, phosphate, dihydrogenphosphate, hydrogenphosphate, propionate, tetrachloroaluminate, Al ₂ Cl ₇ ^" , chlorozincate, chloroferrate, bis (trifluoroethylsulfonyl) imide, Bis (pentafluoroethylsulfonyl) imide, tris (trifluoromethylulfonyl) ethide,

Bis (pentafluoroethylsulfonyl) methide, p-tolylsulfonate, bis [salicylato (2 -)] borate, tetracarbonylcobaltate, dimethylenglycolmonomethylethersulfate, octylsulfate, oleate, stearate, acrylate, methacrylate, maleate, hydrogen citrate, vinylphosphonate, bis (pentafluoroethyl) phosphinate, bis [oxalato ( 2 -)] borate, bis [1, 2-benzenediolato (2 -) - O, 0 '] borate, dicyanamide, tris (pentafluoroethyl) trifluorophosphate, tris (heptafluoropropyl) trifluorophosphate, tetracyano borate or chlorocobaltate.