Oxonium And Sulfonium Salts

A salt (I) having cations selected from the group consisting of

• where
• R1′ denotes CN and
• R2′ to R4′ each, independently of one another, have the meaning
• hydrogen,
• 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,
• dialkylamino containing alkyl groups having 1-4 C atoms, which, however, is not bonded to the heteroatom of the heterocycle,
• saturated, partially or fully unsaturated cycloalkyl having 3-7 C atoms, which may be substituted by alkyl groups having 1-6 C atoms, or
• aryl-C1-C6-alkyl,
• where R2′ and R4′ may be partially or fully substituted by F,
• where R2′ and R3′ may be partially or fully substituted by halogens or partially by NO2 or CN, and
• where, in R2′ to R4′, one or two non-adjacent carbon atoms which are not bonded directly to the heteroatom may be replaced by atoms and/or atom groups
• selected from the group consisting of —O—, —S—, —S(O)— and —SO2—,
• and
• anions selected from the group consisting of [PFx(CyF2y+1−zHz)6−x]− anions, where 2≦x≦5, 1≦y≦8 and 0≦z≦2y+1,
• or anions selected from the group consisting of [BFn(CN)4−n]− anions, where n=0, 1, 2 or 3,
• or anions selected from the group consisting of [(Rf1SO2)2N]− anions, where Rf1 denotes F or perfluorinated and straight-chain or branched alkyl having 1-20 C atoms, perfluorinated and straight-chain or branched alkenyl having 2-20 C atoms and one or more double bonds,
• perfluorinated and straight-chain or branched alkynyl having 2-20 C atoms and one or more triple bonds, perfluorinated and saturated, partially or fully unsaturated cycloalkyl having 3-7 C atoms, which may be substituted by perfluoroalkyl groups,
• or anions selected from the group consisting of [BFwRf24−w]− anions, where w=0, 1, 2 or 3,
• where Rf2 denotes perfluorinated and straight-chain or branched alkyl having 1-20 C atoms,
• perfluorinated and straight-chain or branched alkenyl having 2-20 C atoms and one or more double bonds, perfluorinated and straight-chain or branched alkynyl having 2-20 C atoms and one or more triple bonds, perfluorinated and saturated, partially or fully unsaturated cycloalkyl having 3-7 C atoms, which may be substituted by perfluoroalkyl groups,
• where Rf1 or Rf2 may in each ease be identical or different,
• where Rf1 or Rf2 may be connected to one another in pairs by single or double bonds, and where, in Rf1 or Rf2, one or two non-adjacent carbon atoms which are not in the α-position to the heteroatom may be replaced by atoms and/or atom groups selected from the group consisting of —O—, —SO2— and —NR′— or by the end group —SO2X′, where R′=non-, partially or perfluorinated C1- to C6-alkyl, C3- to C7-cycloalkyl, unsubstituted or substituted phenyl, or an unsubstituted or substituted heterocycle, and X′═F, Cl or Br.

A salt (III) having cations selected from the group consisting of

• where
• R1′ to R4′ each, independently of one another, have the meaning
• straight-chain or branched alkyl having 1-20 C atoms, with the proviso that at least one of the substituents R1′ or R4′ is straight-chain or branched alkyl having 9-20 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 alkyl groups having 1-6 C atoms
• where R1′ and R4′ may be partially or fully substituted by F, but where R1′ and R4′ cannot simultaneously be fully substituted by F,
• where R2′ and R3′ may be partially or fully substituted by OR′, N(R′)2, CN or halogen and
• where, in R1″ to R4′, one or two non-adjacent carbon atoms which are not in the α-position to the heteroatom may be replaced by atoms and/or atom groups selected from the group consisting of —O—, —S—, —SO2— and —NR′— or by the end group CN, —C(O)X′ or —SO2X′, where R′═H, non-, partially or perfluorinated C1- to C6-alkyl, C3- to C7-cycloalkyl, unsubstituted or substituted phenyl, or an unsubstituted or substituted heterocycle, and X′═OH, F, Cl or Br, and
• anions selected from the group consisting of [PFx(CyF2y+1−zHz)6−x]− anions, where 2≦x≦5, 1≦y≦8 and 0≦z≦2y+1, where 3-methyl-1-octadecylimidazolium tris(pentafluoroethyl)trifluorophosphate is excluded.