EP1786761A1

EP1786761A1 - Method for the production of tricyanomethanides of organic cations

Info

Publication number: EP1786761A1
Application number: EP05772429A
Authority: EP
Inventors: Christoph TÄSCHLER; Cornelia Zur Täschler; Andreas Breuer; Felix Previdoli
Original assignee: Lonza AG
Current assignee: Lonza AG
Priority date: 2004-08-25
Filing date: 2005-08-20
Publication date: 2007-05-23
Also published as: CN101010291A; JP2008510753A; KR101198060B1; JP5019456B2; HK1106222A1; WO2006021390A1; EP1634867A1; KR20070047347A; CN101010291B; SG155204A1

Abstract

The invention relates to a method for producing ionic liquids based on tricyanomethane salts of formula (I), wherein Q<sup

Description

Process for the preparation of tricyanomethanides of organic cations

The invention relates to a process for the preparation of ionic liquids of the formula

ffi C ^ ⁺ ι _ Q i

_/ C ^

wherein Q ^{+ is} an organic cation containing at least one heteroatom selected from the group consisting of nitrogen, phosphorus, sulfur and oxygen.

The ionic liquids of formula I are Tricyanomethansalze or Tricyano- methanides. Tricyanomethane metal salts and processes for their preparation are known from Schmidtmann, H., Ber. 29, 1896, 1172 and Trofimenko, S. et al., J. Org. Chem. 27, 1962, 433-438. From Batten, SR et al., Chem. Commun. 1998, 439-440 tri cyanomethan-metal salt complexes are also known with organic ligands. In the synthesis of metal tricyanomethanides, for example Kaliumtricyanomethanid, according to Trofi¬ menko et al. From dibromomalononitrile, potassium cyanide and potassium bromide are formally reacted per mole of tricyanomethanide 1.5 mol Br ₂ .

Various tricyanomethane salts, for example, are still known from EP-A 0850 921, US Pat. No. 3,981,899, Jäger, L. et al., Z. Anorg. Chem. 611, 1992, 62-72, Cioslowski, J. et al., Chem. Phys. Lett. 170, 1990, 297-300, Elvidge, L.A. et al., J. Chem. Soc. Perkin Trans. 1, 8, 1983, 1741-1744 and Makhon'kov, D.I. et al., Zh. Org. Khim. 15, 1979, 2441-2445. However, these are solids only. EP-A 0010396 discloses various liquid ammonium tricyanomethanides which are used as fungicides and herbicides.

Salts of organic cations have a low vapor pressure and often a low melting point. They are called ionic liquids when they are liquid at room temperature. Ionic liquids have become known in recent years as umwelt¬ friendly solvent for a "green chemistry" an ionic liquid and thus the temperature range as a solvent is influenced by variation of the anions and cations. Meanwhile, various ionic liquids are available for applications ranging from about -60 ° C to over 300 ° C.

Usually, the organic cations of ionic liquids are monovalent quaternary ammonium or phosphonium bases, or cations of aromatic, usually nitrogen-containing bases, which are optionally additionally substituted by alkyl groups, halogen atoms or cyano groups and may contain further heteroatoms such as phosphorus, sulfur or oxygen. Examples of common organic cations are imidazolium, oxazolium, pyrazinium, pyrazolium, pyridazinium, pyrrolidinium, pyrimidinium, thiazolium and triazolium cations. Imidazolium and pyrrolidinium cations are the most commonly used. The cations can be delocalized with a charge located on at least one heteroatom, or in the middle of a ring, or else in complex notation. All representations are used equivalently side by side.

Typical anions in ionic liquids are acetate, AlCl ₄ ^" , AsF ₆ -, BF ₄ ^" , bromide, CF ₃ SO ₃ - (CFa) ₂ PF ₄ -, (CF ₃ ) ₃ PF ₃ -, (CF ₃ ) ₄ PF ₂ ^~, (CF ₃₎ ₅ PF, (CFa) ₆ T, chloride, CN, ^"FeCIf, NO ₃ -, PF _^6" pyruvate, oxalate or SCIST. Most commonly AlCl ₄ , AsF ₆ , BF ₄ and PF ₆ ^" are used.

Starting materials for the production of ionic liquids can be, for example, from Merck KGaA, Darmstadt or IoLiTec, A. Bösmann, Dr. med. Schubert G.b.R., Freiburg.

Object of the present invention, it was a new inexpensive process for the preparation of Tricyanomethaniden, which can be disposed of environmentally friendly after use, to provide.

This object is achieved according to claim 1. Claimed is a process for the preparation of ionic liquids of the formula, fi

ΥT ^ N wherein Q ^{+ is} an organic cation selected from the group consisting of cations of the formula, a) [WR ¹ R ² R ³ R ⁴ ] ^"1" , wherein W represents a nitrogen or phosphorus atom, and i) wherein R ¹ to R ^{3 are} independently C _1-20 alkyl, and R ^{4 is} C _1-2 o alkyl, C _3-10 cycloalkyl or C _6-10 aryl, wherein R ¹ to R ⁴ independently of one another optionally contain one or more halogen atoms, or ii) wherein R ¹ and R ² together with W form a 5- to 7-membered ring, and wherein R ³ and R ^{4 are} independently C _1-2 o-alkyl, wherein R ³ and R ⁴ independently of one another optionally contain one or more halogen atoms, or iii) in which R ¹ and R ² , and also R ³ and R ⁴ together with W form a 5- to 7-membered ring, or b) [NR ⁵ R ⁶ R ⁷ J ⁺ , in which N represents a nitrogen atom, and in which R ⁵ and R ⁶ together with N form a ring in which N formally has a single bond and a double bond, and R ⁷ denotes Q 1-6 -alkyl, C _{3- 10} cycloalk yl or C _6-1 o-aryl, wherein R ⁷ optionally contains one or more halogen atoms, or c) [SR ⁸ R ⁹ R ¹⁰ J ⁺ , wherein S represents a sulfur atom, and i) wherein R ⁸ and R ⁹ independently each is C _1-2 o alkyl, and R ^{10 is} C _1-20 alkyl, C _3-1 o cycloalkyl or C _6-1O aryl, wherein R ⁸ through R ¹⁰ independently of one another optionally contain one or more halogen atoms or ii) wherein R ⁸ and R ⁹ together with S form a 5- to 7-membered ring, and R ¹⁰

C _1-20 alkyl, C _3-10 cycloalkyl or C _6-10 aryl, wherein R ¹⁰ optionally contains one or more halogen atoms, or d) [ZR ¹¹ R ¹² J ⁺ , wherein Z is a sulfur or oxygen atom where R ¹¹ and R ¹² together with Z form a ring in which Z formally a single and a

1 1 10 double bond to R and R, and wherein to each of the optionally formed from R ¹ to R ¹² rings one or more substituents selected from the group consisting of C ^ o-alkyl groups, C _1-2 o-alkoxy groups, halogen and cyano be bound, the C _1-2 o-alkyl groups and C _1-20 -alkoxy groups independently of one another optionally contain one or more halogen atoms, and in which each of the rings formed from R ¹ to R ¹² optionally contains one or two further heteroatoms selected from the group consisting of nitrogen, May contain sulfur and oxygen, and / or may be fused to another aromatic or non-aromatic 5- to 7-membered ring comprising mixing malononitrile with a cyano compound of the formula RCN, wherein R is selected from the group consisting of chlorine, bromine , Iodine and cyano in the presence of a base, optionally in the presence of a solvent, and adding a salt (Q ⁺ ) _n X ^{n "} where n = 1 or 2, where Q ^{+ is} as defined above and X ^{n" is} an anion selected from Group consisting of halides, pseudohalides, sulfate and organic acid anions, wherein the anion X ^{n "} in aqueous phase against a tricyanomes formed in situ from malononitrile and RCN thanidanion is exchanged.

In a preferred process variant, malononitrile, the cyano compound of the formula RCN and the salt (Q ⁺ ) _n X ^{n ~} in the presence of a base, if appropriate in the presence of a further solvent, are mixed in an aqueous phase, wherein formation and exchange of the Tricyanomethanidanions take place in a one-pot reaction ,

A specific order of addition of malononitrile, the cyano compound of the formula RCN, the base, and the salt of the formula (Q ⁺ ) _n X ^{n ~} is not mandatory. The order of addition in the examples has been proven in the process engineering process, but in the laboratory, any other order also leads to the formation of the novel compounds.

Both the cyano compound of the formula RCN, and the base and / or the salt of the formula (Q ⁺ ) _n X ^{n "} , wherein R, Q ⁺ , X ^n" and n are as defined above, may be in pure form, as well as a solution, for example in water and / or methanol. Other suitable solvents and / or solubilizers can be selected from the group consisting of acetone, acetonitrile, C ₁ . ₄ - Alcohols, chloroform, dichloroethane, diethyl ether, DMSO, ethyl acetate, hexane, methylene chloride, propylene carbonate, carbon disulfide, THF, toluene, xylene or suitable mixtures thereof. Preference is given to using water-miscible solvents.

In a preferred embodiment, the cyano compound RCN is selected from the group consisting of cyanogen chloride, cyanogen bromide and cyanogen, more preferably cyanogen chloride or cyanogen.

In a further preferred embodiment, the molar ratio of malononitrile to the cyano compound of the formula RCN is in the range from 0.2: 1 to 2: 1, particularly preferably from 0.9: 1 to 1.1: 1, very particularly preferably at 0, 95: 1 to 1.05: 1.

Suitable bases in the process according to the invention can be selected from the group consisting of alkali metal and alkaline earth metal hydroxides, alkali metal and alkaline earth metal carbonates, ammonia, primary, secondary and tertiary amines. The base is particularly preferably an alkali metal hydroxide and alkaline earth metal hydroxide, very particularly preferably sodium hydroxide and / or potassium hydroxide.

In a preferred method, the pH is maintained at a value greater than 4 during the reaction, preferably at a value greater than 7, more preferably in the range from 7 to 9.

The halide as anion X ^{n ~ of} the salt of the formula (Q ⁺ ) _n X ^{n "} may be selected from the group consisting of fluorine, chlorine, bromine and iodine, more preferably chloride.

As pseudohalide anions X ^{n "} in the salt (Q ⁺ ) _n X ^{n ~, it is} possible to use anions which consist of at least two electronegative atoms and which are chemically similar to the halogens.Pseudohalide anions are preferably selected from the group consisting of CN ^" , OCN ^". , SCN ^" and N ₃ ^" . Particularly preferred is CN ^" . Suitable organic acid anions are, for example, anions of monobasic and dibasic nonaromatic and aromatic acids such as, for example, acetate, oleate, fumarate, maleate, pyruvate, oxalate and benzoate. Particularly preferred are acetate and pyruvate.

In a preferred process, the tricyanomethane salts of formula I formed, wherein Q ^{+ is} as defined above, are separated from unreacted starting compounds and purified by extraction procedures.

The erfmdungsgemässe method allows the creation of ionic liquids with a very low chloride content.

An advantage of the method according to the invention is the possibility of providing largely chloride-free and sodium-free ionic liquids.

Here and in the following, the term "C _1-n -alkyl" denotes an unbranched or branched alkyl group having 1 to n carbon atoms, for example C _1-20 -alkyl represents groups such as methyl, ethyl, propyl, isopropyl, butyl , Isobutyl, sec-butyl, tert-butyl, pentyl, 1,4-dimethyl-pentyl, hexyl, heptyl, octyl, 1,5-dimethyl-hexyl, nonyl, decyl, 4-ethyl-l, 5-dimethylhexyl, undecyl , Dodecyl, tridecyl, tetradecyl or eicosyl.

Here and below, the term "C _3-n -cycloalkyl" means a cycloalkyl group having 3 to n carbon atoms. For example, C _3-1 o -cycloalkyl represents groups such as cyclopropyl, cyclobutyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl , Cyclononyl or cyclodecyl.

As used herein, the term "C _6-10 aryl" means an aryl group having from 6 to 10 carbon atoms, for example, C _6-10 aryl represents groups such as phenyl, benzyl, methylphenyl, dimethylphenyl, ethylmethylphenyl, diethylphenyl or naphthyl.

Here and below, the term "C _1-n -alkoxy" denotes an unbranched or branched alkoxy group having 1 to n carbon atoms, for example C _1-2O -alkoxy represents groups such as methoxy, ethoxy, propoxy, isopropoxy, butoxy, isobutoxy , sec-butoxy, tert-butoxy, pentyloxy, 1,4-dimethyl-pentyloxy, hexyloxy, heptyloxy, Octyloxy, 1,5-dimethyl-hexyloxy, nonyloxy, decyloxy, 4-ethyl-l, 5-dimethylhexyloxy, undecyloxy, dodecyloxy, tridecyloxy, tetradecyloxy or eicosyloxy.

As used herein, the term "halogen" means fluoro, chloro, bromo or iodo.

In a preferred embodiment, the cation Q ^{+ contains} at least one 5- to 7-membered aromatic or non-aromatic ring.

In another preferred embodiment, an aromatic or non-aromatic ring in the organic cation Q ^{+ contains} one to two further heteroatoms from the group consisting of nitrogen, sulfur or oxygen. More preferably, the cation Q ⁺ contains another nitrogen or sulfur atom.

Further preferably, one or more substituents from the group consisting of C _1-20 alkyl groups, C _1-20 alkoxy groups, C _3-1 o-cycloalkyl groups, C _6-1 can be attached to an aromatic or nonaromatic ring of the cation Q ⁺ o-aryl groups, halogen and cyano. Here, the C 1-6 -alkyl groups, C _1-20 -alkoxy groups, C _3-1- o-cycloalkyl groups, C _6-1O -aryl groups independently of one another optionally _contain one or more halogen atoms.

In the process according to the invention, the cation Q ⁺ is particularly preferably selected from the group consisting of organic ammonium, phosphonium and sulfonium cations, pyrrolidinium, pyrrolinium, pyrazolium, pyrazolium, imidazolium, tolazolium, oxazolium and thiazolium -, piperidinium, piperazinium, morpholinium, pyridinium, pyridazinium, pyrimidinium, pyrazinium, 1,3-dioxolium, pyrylium, thiopyrylium, Azoniaspiro and Phosphoniaspirokationen.

In another particularly preferred embodiment, the cation Q ^{+ is} selected from the group consisting of N, N-di (C _1-2 o -alkyl) -N, N- (dimethyl) ammonium, N- (C _6-10 -) aryl) -N ^ N-tri (C _1-20 -alkyl) -arimionium, N, N-di (C _6-10 -aryl) -N ₎ iV ^' - (dimethyl) - ammonium, tetramethylphosphonium, tetrabutylphosphonium , Trimethylsulfonium, tributylsulfonium, 1- (C _1-2 o -alkyl) -3-methylpyridinium, 1- (C _1-20 -alkyl) -3-cyano-pyridinium, 1- (C _{1 -20} alkyl) - -methylpyrrolidinium- 1, 1- (C ₁ - ₂₀ - alkyl) - 1, 3 dimethyl piperidinium, 1- (C _1-2 o -alkyl) -1-methylimidazolium, 1- (C _1-20 -alkyl) -3-ethylpyridinium, 4,5-dimethyl-2- (diphenylmethyl) -1, 3-dioxolium, 2- (diphenylmethyl) -4,5-diphenyl-1, 3-dioxolium, 6-azoniaspiro [5.5] undecane and 5-phosphoniaspiro [4.4] non-anions.

Ionic liquids of the formula I in which Q ^{+ is} as defined above may, if appropriate in a mixture with one or more other ionic liquids, water or organic solvents, be used as solvent and in particular as constituent of polar solvents. The tricyano-methanides can be used particularly suitably as conductive solvents in the electrochemical or electrosynthesis, in which the addition of conductive salts can be reduced, or completely omitted.

The polarity of ionic liquids based on tricyanomethanides is lower than with conventional ionic liquids, but higher than with ordinary organic solvents, so that here new applications arise.

Ionic liquids based on tricyanomethanides are relatively nonpolar ionic liquids which have low water solubilities and low viscosities in comparison with other ionic liquids.

The use of ionic liquids based on tricyanomethanides has the advantage over many other ionic liquids that no metal-containing residues are formed during thermal disposal. The compounds obtained by the process according to the invention also have particularly low halide values.

The following examples are intended to illustrate the invention without, however, representing a limitation. Examples:

Example 1: 1-Butyl-1-methylpyrrolidinium chloride

Methylpyrrolidine (150 g, 1.76 mol) is initially introduced and mixed at room temperature with butyl chloride (163 g, 1.76 mol). The resulting reaction mixture is then heated under reflux for 24 h (reaction temperature about 77 ° C) with a slightly yellowish suspension forms. Thereafter, the reaction mixture is cooled to room temperature and filtered. The residue is washed with a little MTBE and then dried at 50 ^° C. in vacuo to give pure 1-butyl-1-methylpyrrolidmium chloride (27 g, 0.09 mol, 8.6% conversion). The remaining material of the reaction mixture consists exclusively of the unreacted starting materials methylpyrrolidine and butyl chloride, which are completely recovered. The melting point of the resulting 1-butyl-1-methylpyrrolidiniumchlorid is 199.5 ° C. ¹ H-NMR (de-DMSO): δ = 3.50 (m, 4H), 3.36 (m, 2H), 3.02 (s, 3H), 2.08 (s br, 4H), 1.68 (m, 2H), 1.33 ( sext, J = 7.3 Hz, 2H) 0.94 ppm (t, J = 7.6 Hz, 3H);

¹³ C NMR (d ₆ -DMSO): δ = 64.0 (CH ₂ ), 63.4 (CH ₂ ), 48.1 (CH ₃ ), 25.6 (CH ₂ ), 21.8 (CH ₂ ), 20.0 (CH ₂ ), 14.2 ppm (CH ₃ ).

Example 2: 1-Butyl-1-methylpyrrolidinium tricyanomethanide Malononitrile (17.8 g, 264 mmol) is initially charged in water (300 ml) and at 0 to 5 ° C cyanogen chloride (16.5 g, 0.268 mmol) is added to the Initiated reaction solution, wherein the pH of the reaction solution is kept during introduction to 8.5 by ent speaking addition of 30% sodium hydroxide solution. The reaction temperature of the solution is kept at 0 to 5 ⁰ C during the introduction of cyanogen chloride for about 1 h. To the reaction mixture is added a mixture of 1-butyl-1-methylpyrrolidinium chloride (47.5 g, 0.267 mmol) in water (150 ml). The organic phase is separated off and the aqueous phase is extracted with dichloromethane (2 × 100 ml). The combined organic phases are extracted with water (4x75 ml). Activated carbon (3 g) is added to the organic phase and the mixture is stirred at RT for 30 min. Subsequently, the organic phase is filtered off and concentrated on a rotary evaporator at 40 to 60 ⁰ C (about 500 mbar to about 20 mbar). This gives 1-butyl-1-methylpyrrolidinium tricyanomethanide (46.8 g, 201 mmol, yield 76%, the chloride content is <0.1%, the viscosity at 20 ° C. is 33 mPas. ¹ H NMR (d ₆ -DMSO): δ = 3.44 (m, 4H), 3.28 (m, 2H), 2.98 (s, 3H), 2.08 (s br, 4H), 1.69

(m, 2H), 1.32 (sec, J = 7.3Hz, 2H), 0.94ppm (t, J = 7.6Hz, 3H);

¹³ C NMR (d ₆ -DMSO): δ = 120.5 (C _q ), 63.5 (CH ₂ ), 63.0 (CH ₂ ), 47.6 (CH ₃ ), 24.9 (CH ₂ ),

21.1 (CH ₂ ), 19.3 (CH ₂ ), 13.4 (CH ₃ ), 4.7 ppm (Cq).

Example 3: 1-Butyl-3-methyl-imidazolium tricyanomethanide

A solution of 1-butyl-3-methylimidazolium chloride (43.1 g, 178 mmol) in water

(100 ml) is as described in Example 2 to a mixture of malononitrile and

Cyanogen chloride added. This gives l-butyl-3-methylimidazolium tricyanomethanid (33.6 g, 147 mmol, 82% yield) with a chloride content of <0.1%. The viscosity at 20 ° C is 30 mPAS.

¹ H NMR (d ₆ -DMSO): δ = 9.05 (s, IH), 7.67 (t, J = 1.8 Hz, IH), 7.61 (t, J = 1.8 Hz, IH),

4.07, (t, J = 7.2 Hz, 2H), 3.83 (s, 3H), 1.80 (t-sept, ¹ J = 12.4 Hz, ² J = 1.8 Hz, 2H), 1.26,

(t-sext, ¹ J = 7.5 Hz, ² J = 1.8 Hz, 2H), 0.89 ppm (t, J = 7.4 Hz, 3H); ¹³ C-NMR (de-DMSO): δ = 136.5 (CH), 123.5 (CH), 122.2 (CH), 120.5 (Cq), 48.6 (CH ₂ ),

35.7 (CH ₃ ), 31.3 (CH ₂ ), 18.8 (CH ₂ ), 13.1 (CH ₃ ), 4.8 ppm (C _q ).

Example 4: 1-Ethyl-3-methylimidazolium tricyanomethanide

A solution of 1-ethyl-3-methylimidazolium chloride (178.4 g, 1.22 mol) in water (180 ml) is prepared as described in Example 2 to a mixture of malononitrile (84.6 g, 1.28 mol) and Cyanogen chloride (79.9 g, 1.30 mol) was added. The resulting reaction mixture gives no phase separation and is first treated with activated carbon (3%) as in Example 2 and then extracted with dichloromethane (300 ml). The organic phase is then washed with water (2 x 200 ml). After concentration on a rotary evaporator at 40 to 60 ⁰ C (about 500 mbar to about 20 mbar) 169.5 g (69% yield) of l-ethyl-3-methyl-imidazoliumtricyanomethanid obtained with a chloride and a sodium content of each less than 10 ppm. ¹ H-NMR (d ₆ -DMSO): δ = 9.09 (s, IH), 7.72 (t, J = 1.7 Hz, IH), 7.64 (t, J = 1.7 Hz, IH), 4.21 ( t, J = 7.4 Hz, 2H), 3.86 (s, 3H), 1.45 ppm (t, J = 7.4 Hz, 3H); ¹³ C NMR (d ₆ -DMSO): δ = 136.4 (CH), 124.4 (CH), 122.8 (CH), 121.7 (Cq), 45.4 (CH ₂ ), 36.7 (CH ₃ ), 15.8 (CH ₃ ) , 6.7 ppm (Cq). Example 5: 1-Butyl-3-methylpyridinium tricyanomethane

A solution of l-butyl-3-methylpyridinium chloride (939.6 g, 5.06 mol) in water (813 ml) is prepared as described in Example 2 to a mixture of malononitrile (351.0 g, 5.31 mol) and Cyanogen chloride (333.1 g, 5.42 mol) was added. The reaction mixture separates into two phases, the aqueous phase being separated and extracted with dichloromethane (1290 ml). The organic phases are combined, treated with charcoal (3%) and then washed with water (4x900 ml). After concentration on a rotary evaporator at 40 to 60 ⁰ C (about 500 mbar to about 20 mbar) 1118 g (92% yield) of l-butyl-3-methylpyridiniumtricyanomethanid obtained with a chloride and a sodium content of each less than 10 ppm.

¹ H NMR (d ₆ -DMSO): δ = 8.95 (s, IH), 8.87 (d, J = 6.1 Hz, IH), 8.40 (d, J = 8.0 Hz, IH), 8.01 ( t, J = 7.1 Hz, IH), 4.53, (t, J = 7.4 Hz, 2H), 2.49 (s, 3H), 1.90 (m, 2H), 1.29, (t-sext, J = 7.5 Hz, 2H), 0.90 ppm (t, J = 7.4 Hz, 3H); ¹³ C NMR (d ₆ -DMSO): δ = 145.5 (CH), 144.1 (CH), 141.8 (CH), 138.7 (C, q), 127.2 (CH), 120.4 (C _q ), 60.4 (CH ₂ ), 32.4 (CH ₂ ), 18.7 (CH ₂ ), 17.7 (CH ₃ ), 13.10 (CH ₃ ), 4.6 ppm (C _q ).

Example 6: 1-Octyl-3-methylpyridinium tricyanomethanide

A solution of 1-octyl-3-methylpyridinium chloride (125.8 g, 520 mmol) in water

(300 ml) is added to a mixture of malononitrile (36.0 g, 534 mmol) and cyanogen chloride (31.4 g, 537 mmol) as described in Example 2. The reaction mixture separates into two phases, the aqueous phase being separated and extracted with dichloromethane (300 ml). The organic phases are combined, treated with charcoal (3%) and then washed with water (4x125 ml). After concentration on a rotary evaporator at 40 to 60 ⁰ C (about 500 mbar to about 20 mbar) gives 137.8 g (89% yield) of l-octyl-3-methylpyridiniumtricyanomethanid with a chloride and a sodium content of less as 100 ppm.

¹ H NMR (d ₆ -DMSO): δ = 8.96 (s, IH), 8.88 (d, J = 6.3 Hz, IH), 8.40 (d, J = 8.0 Hz, IH), 8.01 ( dd, ¹ J = 8.2 Hz, ² J = 6.2 Hz, IH), 4.52 (t, J = 7.4 Hz, 2H), 2.49 (s, 3H), 1.90 (p, J = 7.1 Hz , 2H), 1.26 (m, 10H), 0.83 ppm (m, 3H); ¹³ C NMR (d ₆ -DMSO): δ = 145.5 (CH), 144.0 (CH), 141.8 (CH), 138.7 (C _q ), 127.2 (CH), 120.3 (C _q ), 60.6 (CH ₂ ) , 31.0 (CH ₂ ), 30.5 (CH ₂ ), 28.3 (CH ₂ ), 28.2 (CH ₂ ), 25.3 (CH ₂ ), 21.9 (CH ₂ ), 17.7 (CH ₃ ), 13.7 (CH ₃ ), 4.6 ppm (C _q ).

Claims

claims

1. A process for the preparation of ionic liquids of the formula

wherein Q ^{+ is} an organic cation selected from the group consisting of cations of the formula a) (WR ¹ R ² R ³ RY, wherein W is a nitrogen or phosphorus atom, and i) wherein R ¹ to R ^{3 are} independently C _{1 -20} alkyl, and R ^{4 is} Q ^ o-alkyl, C _3-10 cycloalkyl or C _6-10 aryl, wherein R ¹ to R ⁴ independently of one another optionally contain one or more halogen atoms, or ii) wherein R ¹ and R ² together with W form a 5- to 7-membered ring, and wherein R ³ and R ^{4 are} independently C _1-20 -alkyl, wherein R ³ and R ⁴ independently of one another optionally contain one or more halogen atoms, or iii) wherein R ¹ and R ² , and also R ³ and R ⁴ together with W form a 5- to 7-membered ring, or b) (NR ⁵ R ⁶ R ⁷ ) ⁺ , wherein N represents a nitrogen atom, and wherein R ⁵ and R ⁶ together with N form a ring in which X formally has a single and a double bond to R ⁵ and R ⁶ , and R ^{7 is} C _1-20 -AuYyI, C _3-10 -cyclo-alk yl or C _6-1O -aryl, where R ⁷ optionally contains one or more halogen atoms, or c) (SR ⁸ R ⁹ R ¹ V, in which S denotes a sulfur atom, and i) in which R ⁸ and R ^{9 are} independent each is C _1-2O alkyl, and R ¹⁰

C _1-20 alkyl, Cs.io-cycloalkyl or C _6-10 aryl, wherein R ⁸ to R ¹⁰ independently of one another optionally contain one or more halogen atoms, or ii) wherein R and R together with S a 5- to Form 7-membered ring, and

R ^{10 is} C _1-20 alkyl, C _3-10 cycloalkyl or C _6-1 o-aryl, wherein R ¹⁰ optionally contains one or more halogen atoms, or d) (ZR ^π R ¹² ) ⁺ , wherein Z is an oxygen or sulfur atom, and wherein

R and R together with Z form a ring in which Z formally has a single and a double bond to R ¹¹ and R ¹² , and wherein to each of the rings formed by the substituents R ¹ to R ¹² optionally one or more substituents from the Group consisting of

C _1-2 o-alkyl groups, C _1-20 -alkoxy groups, C _3-10 -cycloalkyl groups, C _6-10 -aryl groups, halogen and cyano, where the C _1-20 -alkyl-, C _1-20 - Alkoxy, C _3-10 cycloalkyl and C _6-10 aryl groups independently of one another optionally contain one or more halogen atoms, and wherein each of the rings formed by the substituents R ¹ to R ¹² optionally contains one or two further heteroatoms from the group Nitrogen, sulfur and oxygen, and / or may be fused to another aromatic or non-aromatic 5- to 7-membered ring comprising mixing malononitrile with a cyano compound of the formula RCN, wherein R is selected from the group consisting of chlorine , Bromine, iodine and cyano in the presence of a base, optionally in the presence of a solvent, and the addition of a salt (Q ⁺ ) _n X ^{n ~} where n = 1 or 2, where Q ^{+ is} as defined above and X ^{n is} an anion selected from the group consisting of halide en, pseudohalides, sulfate and organic acid anions, wherein the anion X ^{n ~ is} exchanged in the aqueous phase for a Tricyano- methanidanion formed in situ from malononitrile and RCN.

2. The method of claim 1, wherein malononitrile, the cyano compound RCN and the salt (Q ^ X ¹ * ^"" in the presence of a base, optionally in the presence of another solvent, are mixed in an aqueous phase and wherein formation and exchange of Tricyanomethanidanions in a One-pot reaction take place.

3. The method according to claim 1 or 2, wherein the molar ratio of malononitrile dinitrile to cyano compound RCN in the range of 0.2: 1 to 2: 1, more preferably from 0.9: 1 to 1.1: 1, completely more preferably 0.95: 1 to 1.05: 1.

4. The method according to any one of claims 1 to 3, wherein the base is selected from the group consisting of alkali and alkaline earth metal hydroxides, alkali and Erdalkali- carbonates, ammonia, primary, secondary and tertiary amines, pyridines and imidazoles.

5. The method according to any one of claims 1 to 4, wherein the pH is maintained during the reaction at a value greater than 4, preferably at a value greater than 7, more preferably in the range of 7 to 9.

A process according to any one of claims 1 to 5, wherein the anion X ^{n ~ is} selected from the group consisting of chloride, bromide and cyanide.