Compounds containing alkyl-cyano-borate or alkyl-cyano-fluoroborate anions

1. A compound of formula I

[Kt] z+ z[(R 1 ) 4-x-y-v B(CN) x (NC) y F v ] −   I

in which

R 1 in each case independently denotes a straight-chain or branched alkyl group having 1 to 20 C atoms, which optionally contains at least one Cl, Br or I atom, at least one CN group and/or one or more oxygen or sulphur atoms, a straight-chain or branched alkenyl group having 2 to 20 C atoms having one or more double bonds, which optionally contains at least one Cl, Br or I atom and/or one or more oxygen or sulphur atoms, a straight-chain or branched alkinyl group having 1 to 20 C atoms having one or more triple bonds, which optionally contains at least one Cl, Br or I atom and/or one or more oxygen or sulphur atoms and optionally may have a double bond, or unsubstituted phenyl,

z is 1, 2, 3 or 4,

x is 1, 2 or 3,

y is 0, 1 or 2,

v is 0, 1 or 2,

the sum of x+y+v is 2 or 3,

Kt z+ denotes an inorganic cation selected from NO + , H + , Li + , Na + , K + , Rb + , Cs + , Mg 2+ , Cu + , Cu 2+ , Zn 2+ , Ag + , Ca 2+ , Y +3 , Yb +3 , La +3 , Sc +3 , Ce +3 , Nd +3 , Tb +3 , Sm +3 or complex (ligands containing) metal cations which include rare-earths, transitions or noble metals

or an organic cation selected from

(a) a tritylium cation, in which the phenyl groups may be substituted by straight-chain or branched alkyl groups having 1 to 20 C atoms, straight-chain or branched alkenyl having 2 to 20 C atoms and one or more double bonds or straight-chain or branched alkynyl having 2 to 20 C atoms and one or more triple bonds,

(b) an oxonium cation of formula (1) or a sulfonium cation of formula (2))

[(R o ) 3 O] +   (1)

[(R o ) 3 S] +   (2),

where R o each, independently of one another, denotes a straight-chain or branched alkyl group having 1-8 C atoms, non-substituted phenyl or phenyl which is substituted by R 1 *, OR′, N(R′) 2 , CN or halogen and in case of sulfonium cations of formula (2) additionally denotes each independently (R′″) 2 N,

 R′ is independently of each other H, non-fluorinated, partially fluorinated or perfluorinated straight-chain or branched C 1 - to C 18 -alkyl, saturated C 3 - to C 7 -cycloalkyl, non-substituted or substituted phenyl,

 R 1 * is independently of each other non-fluorinated, partially fluorinated or perfluorinated straight-chain or branched C 1 - to C 18 -alkyl, saturated C 3 - to C 7 -cycloalkyl, non-substituted or substituted phenyl, and

 R′″ is independently of each other straight-chain or branched C 1 to C 6 alkyl,

(c) an ammonium cation, which conforms to the formula (3)

[NR 4 ] +   (3),

where R in each case, independently of one another, denotes H, OR′, N(R′) 2 , with the proviso that a maximum of one R in formula (3) is OR′ or N(R′) 2 ,

 straight-chain or branched alkyl having 1-20 C atoms,

 straight-chain or branched alkenyl having 2-20 C atoms and one or more double bonds,

 straight-chain or branched alkynyl having 2-20 C atoms and one or more triple bonds, saturated, partially or fully unsaturated cycloalkyl having 3-7 C atoms, which may be

 substituted by straight-chain or branched alkyl groups having 1-6 C atoms,

where one or two R may be fully substituted by halogens, and one or more of the substituents R may be partially substituted by halogens, and/or by —OH, —OR′, —CN, —N(R′) 2 , —C(O)OH, —C(O)OR′, —C(O)R′, —C(O)N(R′) 2 , —SO 2 N(R′) 2 , —C(O)X, —SO 2 OH, —SO 2 X, —NO 2 , —SR′, —S(O)R′, or —SO 2 R′ and where one or two non-adjacent carbon atoms in R which are not in the α-position may each be replaced by —O—, —S—, —S(O)—, —SO 2 —, —SO 2 O—, —C(O)—, —C(O)O—, —N + (R′) 2 —, —P(O)R′O—, —C(O)NR′—, —SO 2 NR′—, —OP(O)R′O—, —P(O)(N(R′) 2 )NR′—, —P(R′) 2 ═N— or —P(O)R′—,

R′ in each case independently is H, non-fluorinated, partially fluorinated or perfluorinated straight-chain or branched C 1 - to C 18 -alkyl, saturated C 3 - to C 7 -cycloalkyl, non-substituted or substituted phenyl, and

X in each case, independently of one another, is halogen;

(d) a phosphonium cation, which conforms to the formula (4)

[P(R 2 ) 4 ] +   (4),

where R 2 in each case, independently of one another, denotes H, OR′ or N(R′) 2 ,

 straight-chain or branched alkyl having 1-20 C atoms,

 straight-chain or branched alkenyl having 2-20 C atoms and one or more double bonds,

 straight-chain or branched alkynyl having 2-20 C atoms and one or more triple bonds,

 saturated, partially or fully unsaturated cycloalkyl having 3-7 C atoms, which may be substituted by straight-chain or branched alkyl groups having 1-6 C atoms,

where one or two R 2 may be fully substituted by halogens, and one or more of the substituents R 2 may be partially substituted by halogens, and/or by —OH, —OR′, —CN, —N(R′) 2 , —C(O)OH, —C(O)OR′, —C(O)R′, —C(O)N(R′) 2 , —SO 2 N(R′) 2 , —C(O)X, —SO 2 OH, —SO 2 X, —NO 2 , —SR′, —S(O)R′, or —SO 2 R′, and where one or two non-adjacent carbon atoms in R 2 which are not in the α-position may each be replaced by —O—, —S—, —S(O)—, —SO 2 —, —SO 2 O—, —C(O)—, —C(O)O—, —N + (R′) 2 —, —P(O)R′O—, —C(O)NR′—, —SO 2 NR′—, —OP(O)R′O—, —P(O)(N(R′) 2 )NR′—, —P(R′) 2 ═N— or —P(O)R′—,

R′ in each case independently is H, non-fluorinated, partially fluorinated or perfluorinated straight-chain or branched C 1 - to C 18 -alkyl, saturated C 3 - to C 7 -cycloalkyl, non-substituted or substituted phenyl, and

X in each case independently is halogen,

(e) a uronium cation, which conforms to the formula (5)

[C(NR 3 R 4 )(OR 5 )(NR 6 R 7 )] +   (5),

where R 3 to R 7 each, independently of one another, denote H, where H is excluded for R 5 ,

 straight-chain or branched alkyl having 1 to 20 C atoms,

 straight-chain or branched alkenyl having 2-20 C atoms and one or more double bonds,

 straight-chain or branched alkynyl having 2-20 C atoms and one or more triple bonds,

 saturated, partially or fully unsaturated cycloalkyl having 3-7 C atoms, which may be substituted by straight-chain or branched alkyl groups having 1-6 C atoms,

where one or two of the substituents R 3 to R 7 may be fully substituted by halogens, and one or more of the substituents R 3 to R 7 may be partially substituted by halogens, and/or by —OH, —OR′, —N(R′) 2 , —CN, —C(O)OH, —C(O)OR′, —C(O)R′, —C(O)N(R′) 2 , —SO 2 N(R′) 2 , —C(O)X, —SO 2 OH, —SO 2 X, —SR′, —S(O)R′, —SO 2 R′, or —NO 2 , and where one or two non-adjacent carbon atoms in R 3 to R 7 which are not in the α-position may each be replaced by —O—, —S—, —S(O)—, —SO 2 —, —SO 2 O—, —C(O)—, —C(O)O—, —N + (R′) 2 —, —P(O)R′O—, —C(O)NR′—, —SO 2 NR′—, —OP(O)R′O—, —P(O)(N(R′) 2 )NR′—, —P(R′) 2 ═N— or —P(O)R′—,

R′ in each case independently is H, non-fluorinated, partially fluorinated or perfluorinated straight-chain or branched C 1 - to C 18 -alkyl, saturated C 3 - to C 7 -cycloalkyl, non-substituted or substituted phenyl, and

X in each case independently is halogen,

(f) a thiouronium cation, which conforms to the formula (6)

[C(NR 3 R 4 )(SR 5 )(NR 6 R 7 )] +   (6),

where R 3 to R 7 each, independently of one another, denote H, where H is excluded for R 5 ,

 straight-chain or branched alkyl having 1 to 20 C atoms,

 straight-chain or branched alkenyl having 2-20 C atoms and one or more double bonds,

 straight-chain or branched alkynyl having 2-20 C atoms and one or more triple bonds,

 saturated, partially or fully unsaturated cycloalkyl having 3-7 C atoms, which may be substituted by straight-chain or branched alkyl groups having 1-6 C atoms,

where one or two of the substituents R 3 to R 7 may be fully substituted by halogens, and one or more of the substituents R 3 to R 7 may be partially substituted by halogens, and/or by —OH, —OR′, —N(R′) 2 , —CN, —C(O)OH, —C(O)OR′, —C(O)R′, —C(O)N(R′) 2 , —SO 2 N(R′) 2 , —C(O)X, —SO 2 OH, —SO 2 X, —SR′, —S(O)R′, —SO 2 R′, or —NO 2 , and where one or two non-adjacent carbon atoms in R 3 to R 7 which are not in the α-position may each be replaced by —O—, —S—, —S(O)—, —SO 2 —, —SO 2 O—, —C(O)—, —C(O)O—, —N + (R′) 2 —, —P(O)R′O—, —C(O)NR′—, —SO 2 NR′—, —OP(O)R′O—, —P(O)(N(R′) 2 )NR′—, —P(R′) 2 ═N— or —P(O)R′—,

R′ in each case independently is H, non-fluorinated, partially fluorinated or perfluorinated straight-chain or branched C 1 - to C 18 -alkyl, saturated C 3 - to C 7 -cycloalkyl, non-substituted or substituted phenyl, and

X in each case independently is halogen,

(g) a guanidinium cation, which conforms to the formula (7)

[C(NR 8 R 9 )(NR 10 R 11 )(NR 12 R 13 )] +   (7),

where R 8 to R 13 each, independently of one another, denote H, —CN, N(R′) 2 , —OR′,

 straight-chain or branched alkyl having 1 to 20 C atoms,

 straight-chain or branched alkenyl having 2-20 C atoms and one or more double bonds,

 straight-chain or branched alkynyl having 2-20 C atoms and one or more triple bonds,

 saturated, partially or fully unsaturated cycloalkyl having 3-7 C atoms, which may be substituted by straight-chain or branched alkyl groups having 1-6 C atoms,

where one or two of the substituents R 8 to R 13 may be fully substituted by halogens and one or more of the substituents R 8 to R 13 may be partially substituted by halogens, and/or by —OH, —OR′, —N(R′) 2 , —CN, —C(O)OH, —C(O)OR′, —C(O)R′, —C(O)N(R′) 2 , —SO 2 N(R′) 2 , —C(O)X, —SO 2 OH, —SO 2 X, —SR′, —S(O)R′, —SO 2 R′, or —NO 2 , and where one or two non-adjacent carbon atoms in R 8 to R 13 which are not in the α-position may each be replaced by —O—, —S—, —S(O)—, —SO 2 —, —SO 2 O—, —C(O)—, —C(O)O—, —N + (R′) 2 —, —P(O)R′O—, —C(O)NR′—, —SO 2 NR′—, —OP(O)R′O—, —P(O)(N(R′) 2 )NR′—, —P(R′) 2 ═N— or —P(O)R′—, where

R′ in each case independently is H, non-fluorinated, partially fluorinated or perfluorinated straight-chain or branched C 1 - to C 18 -alkyl, saturated C 3 - to C 7 -cycloalkyl, non-substituted or substituted phenyl, and

X in each case independently is halogen;

(h) a heterocyclic cation which conforms to the formula (8)

[HetN] z+   (8)

where HetN z+ denotes a heterocyclic cation selected from

where the substituents R 1 ′ to R 4 ′ each, independently of one another, denote H,

 straight-chain or branched alkyl having 1-20 C atoms,

 straight-chain or branched alkenyl having 2-20 C atoms and one or more double bonds,

 straight-chain or branched alkynyl having 2-20 C atoms and one or more triple bonds, and

R 2′ each, independently of one another, additionally denotes F, Cl, Br, I, —CN, —OR′, —N(R′) 2 , —P(O)(R′) 2 , —P(O)(OR′) 2 , —P(O)(N(R′) 2 ) 2 , —C(O)R′, —C(O)OR′, —C(O)X, —C(O)N(R′) 2 , —SO 2 N(R′) 2 , —SO 2 OH, —SO 2 X, —SR′, —S(O)R′, —SO 2 R′ or NO 2 , with the proviso that R 1 ′, R 3 ′, R 4 ′ are in this case independently of each other H and/or a straight-chain or branched alkyl having 1-20 C atoms, straight-chain or branched alkenyl having 2-20 C atoms and one or more double bonds, where one to three substituents R 1′ to R 4′ may be fully substituted by halogens, and one or more substituents R 1′ to R 4′ may be partially substituted by halogens, and/or by —OH, —OR′, N(R′) 2 , —CN, —C(O)OH, —C(O)OR′, —C(O)R′, —C(O)N(R′) 2 , —SO 2 N(R′) 2 , —C(O)X, —SO 2 OH, —SO 2 X, —SR′, —S(O)R′, —SO 2 R′, or —NO 2 , but where R 1′ and R 4′ cannot simultaneously be fully substituted by halogens, and

where, in the substituents R 1′ to R 4′ , one or two non-adjacent carbon atoms which are not bonded to the heteroatom may each be replaced by —O—, —S—, —S(O)—, —SO 2 —, —SO 2 O—, —C(O)—, —C(O)O—, —N + (R′) 2 —, —P(O)R′O—, —C(O)NR′—, —SO 2 NR′—, —OP(O)R′O—, —P(O)(N(R′) 2 )NR′—, —P(R′) 2 ═N— or —P(O)R′—,

R′ in each case independently is H, non-fluorinated, partially fluorinated or perfluorinated straight-chain or branched C 1 - to C 18 -alkyl, saturated C 3 - to C 7 -cycloalkyl, non-substituted or substituted phenyl, and

X in each case independently is halogen, or

(i) a iodonium cation which conforms to the formula (9)

where the aryl group Ar denotes each independently of each other aryl with 6 to 30 C atoms which is non-substituted or substituted with at least a straight-chain or branched alkyl group having 1 to 20 C atoms, a straight-chain or branched alkenyl group having 2 to 20 C atoms and one or more double bonds, a straight-chain or branched alkynyl group having 2 to 20 C atoms and one or more triple bonds, R 1 *, NO 2 , SR′, N(R′) 2 , CN and/or halogen, and

R′ each independently is H, non-fluorinated, partially fluorinated or perfluorinated straight-chain or branched C 1 - to C 18 -alkyl, saturated C 3 - to C 7 -cycloalkyl, non-substituted or substituted phenyl,

R 1 * each independently is non-fluorinated, partially fluorinated or perfluorinated straight-chain or branched C 1 - to C 18 -alkyl, saturated C 3 - to C 7 -cycloalkyl, non-substituted or substituted phenyl, and

halogen is F, Cl, Br or I,

with the proviso that potassium (18-crone-6) tricyano-n-octylborate and tetraethylammonium phenyl-tricyanoborate are excluded.

2. A compound according to claim 1 , wherein R 1 in each case independently is a straight-chain or branched alkyl group having 1 to 4 C atoms, which optionally contains at least one Br atom or at least one CN group or at least one oxygen atom or a straight-chain or branched alkenyl having 2 to 4 C atoms.

3. A process for the preparation of a compound according to claim 1 in which [Kt] z+ is an alkali metal cation, z denotes 1 and the sum of x+y+v denotes 3, which denotes a compound of formula I-1,

[Me] + [(R 1 ) 4-x-y-z B(CN) x (NC) y F v ] −   I-1,

in which [Me] + denotes an alkali metal cation and R 1 , x, y and v have the meanings according to claim 1 , said process comprising:

reacting a compound of formula II

[Me] + [(R 1 )BF 3 ] −   II

in which [Me 1 ] + denotes an alkali metal cation and R 1 has a meaning according to claim 1 ,

with a trialkylsilylcyanide, in which the alkyl groups are each independently of one another straight-chain or branched alkyl having 1 to 8 C atoms.

4. A process for the preparation of a compound according to claim 1 in which [Kt] z+ is an organic cation and the sum of x+y+v denotes 3, said process comprising:

reacting a compound of formula III

[Kt] z+ [(R 1 )BF 3 ] −   III

in which [Kt] z+ denotes the organic cation and R 1 has a meaning according to claim 1 ,

with a trialkylsilylcyanide, in which the alkyl groups are each independently of one another straight-chain or branched alkyl having 1 to 8 C atoms.

5. A process for the preparation of a compound according to claim 1 in which [Kt] z+ is alkali metal cation, z denotes 1 and the sum of x+y+v denotes 2, said process comprising:

reacting a compound of formula IV

(R 1 ) 2 BOCH 3   IV

in which R 1 has a meaning according to claim 1 ,

with a trialkylsilylcyanide in the presence of an alkali metal fluoride, wherein the alkyl groups within the trialkylsilylcyanide are each independently of one another straight-chain or branched alkyl having 1 to 8 C atoms.

6. A process for the preparation of a compound according to claim 1 in which [Kt] z+ is another cation than the used alkali metal cation in the starting material in a salt-exchange reaction, said process comprising:

reacting an alkali metal salt of formula I-1

[Me] + [(R 1 ) 4-x-y-z B(CN) x (NC) y F v ] −   I-1

in which [Me] + is an alkali metal cation and R 1 , x, y, v and the sum of x+y+v have the meanings according to claim 1 ,

with a compound of formula V

KtA  V,

in which

Kt has a meaning of an organic cation or an inorganic cation other than the alkali metal cation of the compound of formula I-1, and

A denotes F − , Cl − , Br − , I − , OH − , [HF 2 ] − , [CN] − , [SCN] − , [R 1 COO] − , [R 1 OC(O)O] − , [R 1 SO 3 ] − , [R 2 COO] − , [R 2 SO 3 ] − , [R 1 OSO 3 ] − , [BF 4 ] − , [PF 6 ] − , [HSO 4 ] 1− , [NO 3 ] − , [(R 2 ) 2 P(O)O] − , [R 2 P(O)O 2 ] 2− , [(R 1 O) 2 P(O)O] − , [(R 1 O)P(O)O 2 ] 2− , [(R 1 O)R 1 P(O)O] − , tosylate, malonate which may be substituted by straight-chain or branched alkyl groups having 1 to 4 C atoms, [HOCO 2 ] − or [CO 3 ] 2− (merely for the synthesis of other compounds of formula I-1 having another alkali metal cation than the starting material),

R 1 is each independently of another a straight-chain or branched alkyl group having 1 to 12 C atoms, and

R 2 is each independently of one another a straight-chain or branched perfluorinated alkyl group having 1 to 12 C atoms and where electroneutrality should be taken into consideration in the formula of the salt KtA.

7. An electrolyte formulation comprising at least one compound according to claim 1 .

8. An electrochemical and/or optoelectronic device comprising an electrolyte formulation according to claim 7 .

9. A catalyst, conducting salt, electrolyte, surfactant, phase-transfer catalyst, entrainer, extractant, antistatic additive, plasticizer, heat-transfer-medium, modifier for membranes and textile materials, lubricant, or hydraulic fluid comprising a compound according to claim 1 in which [Kt] z+ is an organic cation or H + and z is 1, 2, 3 or 4.

10. An electrolyte according to claim 7 , in which [Kt] zt is Li + as conducting salt and/or component of electrolytes.

11. A catalyst, conducting salt, electrolyte, surfactant, phase-transfer catalyst, or antistatic additive comprising a compound according to claim 1 in which [Kt] z+ is an inorganic cation.

12. A process according to claim 6 , in which [Kt] z+ is an organic cation and z is 1, 2, 3 or 4.

13. A cationic polymerization initiator, photo-polymerization initiator or photo-acid generator comprising a compound according to claim 1 in which [Kt] z+ is a cation of formula (2), (5), (6), (9), tritylium, pyrylium, 1-benzopyrylium or 2-benzopyrylium.

14. A curable composition comprising at least one compound according to claim 1 with cations of formula (2), (5), (6), (9), tritylium, pyrylium, 1-benzopyrylium or 2-benzopyrylium, and at least one polymerizable compound.

15. A compound according to claim 1 , wherein R 1 in each case independently denotes

a straight-chain or branched alkyl group having 1 to 20 C atoms, which optionally contains at least one Cl, Br or I atom, at least one CN group and/or one or more oxygen or sulphur atoms,

a straight-chain or branched alkenyl group having 2 to 20 C atoms having one or more double bonds, which optionally contains at least one Cl, Br or I atom and/or one or more oxygen or sulphur atoms, or

a straight-chain or branched alkinyl group having 1 to 20 C atoms having one or more triple bonds, which optionally contains at least one Cl, Br or I atom and/or one or more oxygen or sulphur atoms and optionally may have a double bond.

16. A compound according to claim 1 , wherein said compound is potassium methyldicyanofluoroborate, potassium methyltricyanoborate, potassium methyldicyanoisocyanoborate, potassium n-butyldicyanoisocyanoborate, potassium n-butyltricyanoborate, 1-ethyl-3-methylimidazolium n-butyltricyanoborate, potassium allyltricyanoborate, 1-ethyl-3-methylimidazolium methyldicyanofluoroborate, 1-ethyl-3-methylimiazolium methylcyanodifluoroborate, 1-ethyl-3-methylimidazolium tricyano-methylborate, 1-butyl-3-methylimidazolium methyltricyanoborate, triethylsulfonium methyltricyanoborate, methyldiphenylsulfonium methyltricyanoborate, triphenylsulfonium methyltricyanoborate, diphenyliodonium methyltricyanoborate, 2,4,6-triphenylpyrylium methyltricyanoborate, triphenylcarbenium methyltricyanoborate, 1-ethyl-3-methyl-imidazolium vinyltricyanoborate, butylmethylpyrrolidinium tricyanomethylborate, tetrabutylammonium tricyanomethylborate, tetraphenylphosphonium diethyldicyanoborate, 1-ethyl-3-methylimidazolium vinyldicyano-isocyanoborate, potassium methyldicyano-fluoroborate, 1-ethyl-3-methylimidazolium methyldicyanofluoroborate, 1-butyl-1-methylpyrrolidinium methyldicyanofluoroborate, potassium cyanomethyldicyanofluoroborate, 1-ethyl-3-methylimidazolium cyanomethyldicyanofluoroborate, 1-ethyl-3-methylimidazolium cyanomethylcyanodifluoroborate, potassium diethyldicyanoborate, 1-butyl-3-methylimidazolium diethyldicyanoborate, N-butyl-N-methylpyrrolidinium diethyldicyanoborate, or N-butylpyridinium diethyldicyanoborate.

17. A compound according to claim 1 , wherein said compound is of formula IA:

[Kt] z+ z[(R 1 )B(CN) 2 F] −   IA,

wherein [Kt] z+ , z and R 1 have the meanings defined in claim 1 .

18. A compound according to claim 1 , wherein said compound is of formula IB:

[Kt]z+z[(R 1 )B(CN) 3 ] −   IB,

wherein [Kt] z+ , z and R 1 have the meanings defined in claim 1 .

19. A compound according to claim 1 , wherein said compound is of formula IC:

[Kt] z+ z[(R 1 )B(CN) 2 (NC)] −   IC,

wherein [Kt] z+ , z and R 1 have the meanings defined in claim 1 .

20. A compound according to claim 1 , wherein said compound is of formula ID:

[Kt] z+ z[(R 1 )B(CN)F 2 ] −   ID,

wherein [Kt] z+ , z and R 1 have the meanings defined in claim 1 .

21. A compound according to claim 1 , wherein said compound is of formula IE:

[Kt]z+z[(R 1 ) 2 B(CN) 2 ] −   IE,

wherein [Kt] z+ , z and R 1 have the meanings defined in claim 1 .

22. A compound according to claim 1 , wherein said cation is of formula (2) and is selected from diethyl-methylsulfonium, triethylsulfonium, triphenylsulfonium, diphenyltolylsulfonium, diphenylethylsulfonium, diphenyl-2,2,2-trifluorethyl sulfonium, diphenyl-2-ethoxy-ethylsulfonium, diphenyl-2-chlorethylsulfonium, diphenyl-3-brompropylsulfonium, diphenyl-3-chlorpropylsulfonium, diphenyl-3-cyanopropylsulfonium, diphenylallylsulfonium, diphenyl-4-pentenylsulfonium, diphenylpropargylsulfonium, diphenylbenzylsulfonium, diphenyl(p-cyanobenzyl)sulfonium, diphenyl(p-methylbenzyl)sulfonium, diphenyl(p-phenylthiobenzyl)sulfonium, diphenyl(3,3-dicyano-2-phenyl-2-propenyl)sulfonium, diphenyl(p-methylphenacyl)sulfonium, diphenyl(ethylcarboxy)methylsulfonium, diphenyl(n-octyl)sulfonium, diphenyl(n-octadecyl)sulfonium, diphenyl(ω-carboxytridecyl)sulfonium, diphenyl(3-oxypropyl)sulfonium, diphenyl(ω-carboxydodecyl)sulfonium, dihexyl-phenylsulfonium, ditolylphenylsulfonium, tritolylsulfonium, m- or p-(tert-butyl)phenyl-diphenylsulfonium, m- or p-methoxyphenyl-diphenylsulfonium, m- or p-CN-phenyl-diphenylsulfonium, m- or p-C 6 H 13 S-phenyl-diphenylsulfonium, m- or p-C 6 H 5 S-phenyl-diphenylsulfonium, Tri(p-methoxyphenyl)sulfonium, tri[4-(4-acetyl-phenylsulfanyl)phenyl]sulfonium, or tri(4-tert.-butylphenyl)sulfonium.

23. A compound according to claim 1 , wherein said cation is of formula (3) and R in each case is independently selected from methyl, ethyl, isopropyl, propyl, n-butyl, sec-butyl, pentyl, hexyl, octyl, decyl or tetradecyl.

24. A compound according to claim 1 , wherein said cation is of formula (4) and R 2 in each case is independently selected from methyl, ethyl, isopropyl, propyl, n-butyl, sec-butyl, pentyl, hexyl, octyl, decyl or tetradecyl.

25. A compound according to claim 1 , wherein said cation is of formula (8) and is selected from:

where the substituents R 1′ to R 4′ each, independently of one another, have the meanings indicated in claim 1 .

26. A compound according to claim 1 , wherein said cation is selected from 1-butyl-1-methylpyrrolidinium, 1-ethyl-3-methylimidazolium, 1-ethyl-2,3-dimethylimidazolium, 1-(2-methoxyethyl)-3-methylimidazolium, 1-butyl-3-methylimidazolium, tributyl-methylammonium, tetra-n-butylammonium, tributyl-methylphosphonium, tetra-phenylphosphonium, diethyl-methylsulfonium, S-ethyl-N,N,N′,N′-tetramethylisothiouronium, 1-allyl-3-methylimidazolium, 1-allyl-2,3-dimethylimidazolium, 1-cyanomethyl-3-methylimidazolium, 1-methyl-3-propinylimidazlium, 1,1-dimethylpyrrolidinium, or trimethylsulfonium.