Substituted imidazolium sulfuranes and their use

Process comprising reacting a compound of the formula (I):

• wherein
• R1 and R2 each independently represent hydrogen, alkyl, aralkyl, aryl, heteroaryl, each being optionally substituted by one or more hetero atoms selected from O, N, S or halogen, or R1 and R2 may together form a hydrocarbon ring structure, optionally substituted by one or more hetero atoms selected from O, N, S and halogen;
• R3 and R4 each independently represent a lower alkyl group having 1 to 6 carbon atoms, each lower alkyl group being optionally substituted by one or more hetero atoms selected from O, N, S or halogen;
• X is an anion selected from halogen or a non- or weak-coordinating anion;
• Y represents a group of the —C≡W formula wherein W represents N, CR5,
• or C—CO2R5 wherein R5 is selected from the group consisting of C1 to C20 straight chain, branched chain or cyclic aliphatic hydrocarbons, optionally having one or more unsaturated bonds or C6 to C20 aromatic hydrocarbons and partially arene-hydrogenated hydrocarbons, each hydrocarbon optionally being substituted by one or more hetero atoms selected from O, N, S, halogen or a silylgroup;
• with an organic nucleophilic compound RN—H wherein RN is alkyl, aralkyl, aryl or heteroaryl, each being optionally substituted by one or more hetero atoms selected from O, N, and S,
• in an organic solvent, and optionally in the presence of a Lewis acid catalyst, resulting in a transfer of the group Y in order to yield a compound of the formula RN—Y.

An imidazolium sulfurane of the formula (I):

• wherein:
• R1 and R2 each independently represent alkyl, aralkyl, aryl, heteroaryl, each being optionally substituted by one or more hetero atoms selected from O, N, S or halogen, or R1 and R2 may together form a hydrocarbon ring structure, optionally substituted by one or more hetero atoms selected from O, N, S and halogen;
• R3 and R4 each independently represent a lower alkyl group having 1 to 6 carbon atoms, each lower alkyl group being optionally substituted by one or more hetero atoms selected from O, N, S or halogen;
• X is an anion selected from halogen or a non- or weak-coordinating anion;
• Y represents a group of the —C≡W formula wherein W represents N, CR5,
• or C—CO2R5 wherein R5 is selected from the group consisting of C1 to C20 straight chain, branched chain or cyclic aliphatic hydrocarbons, optionally having one or more unsaturated bonds or C6 to C20 aromatic hydrocarbons and partially arene-hydrogenated hydrocarbons, each hydrocarbon optionally being substituted by one or more hetero atoms selected from O, N, S, halogen or a silylgroup.

An imidazolium sulfurane of the formula (I):

• wherein:
• R1 and R2 each independently represent hydrogen, alkyl, aralkyl, aryl, heteroaryl, each being optionally substituted by one or more hetero atoms selected from O, N, S or halogen, or R1 and R2 may together form a hydrocarbon ring structure, optionally substituted by one or more hetero atoms selected from O, N, S and halogen;
• R3 and R4 each independently represent a lower alkyl group having 2 to 6 carbon atoms, each lower alkyl group being optionally substituted by one or more hetero atoms selected from O, N, S or halogen;
• X is an anion selected from halogen or a non- or weak-coordinating anion;
• Y represents a group of the —C≡W formula wherein W represents N, CR5,
• or C—CO2R5 wherein R5 is selected from the group consisting of C1 to C20 straight chain, branched chain or cyclic aliphatic hydrocarbons, optionally having one or more unsaturated bonds or C6 to C20 aromatic hydrocarbons and partially arene-hydrogenated hydrocarbons, each hydrocarbon optionally being substituted by one or more hetero atoms selected from O, N, S, halogen or a silylgroup.