TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Compound: The ionic liquid contains sulfonium ion containing organic compound of formula (1). The ionic liquid further contains an anion component along with the cation component.R1-R8=H, 1-30C alkyl, 2-30C alkenyl having single or multiple double bonds, 2-30C alkynyl having single or multiple triple bonds, cycloalkyl, aryl or heterocyclic hydrogen atom of R1-R8 is optionally substituted by halogen, CN or NO2, and carbon atom of R1-R8 is optionally substituted by -O-, Si(R')2-, -C(O)-, -C(O)O-, -S-, -S(O)-, -SO2-, -SO3-, -N=, -N=N-, -NH-, -NR'-, PR'-, -P(O)R'-, -P(O)R'-O-, -O-P(O)R'-O- or -P(R')2=N-;R'=1-10C alkyl, alkyl optionally substituted by fluorine, cycloalkyl, (un)substituted (phenyl or heterocycle);X1,X2=nitrogen, oxygen or carbon;R4,R7=substituents that exists only when X1 or X2 is nitrogen or carbon;R5,R8=substituents that exists only when X1 or X2 is carbon;anddotted line=conjugated structure.R1-R8 optionally combine to form cyclic structure, when X1 is carbon X1, R3,R4 and R5 optionally combine to form cyclic structure, when X2 is carbon X2, R6,R7 and R8 optionally combine to form cyclic structure, when X1 is nitrogen X1, R3 and R4 optionally combine to form cyclic structure, and when X2 is nitrogen X2, R6 and R7 optionally combine to form cyclic structure. Preferred Component: The anion component is selected from (RSO3)-, (RfSO3)-, ((RfSO2)2N)-, ((FSO2)2N)-, ((RfSO2)3C)-, ((FSO2)3C)-, (ROSO3)-, (RC(O)O)-, (RfC(O)O)-, (CCl3C(O)O)-, ((CN)3C)-,((CN)2CR)-,((RO(O)C)2CR)-, (R2P(O)O)-, (RP(O)O2)2-, ((RO)2P(O)O)-, ((RO)P(O)O2)2-, ((RO)(R)P(O)O)-, (Rf2P(O)O)-, ((RfO)2P(O)O)-, (RfP(O)O2)2-, (B(OR)4)-, BRf4-, (N(CF3)2)-, (N(CN)2)-, (AlCl4)-, PF6-, (RfPF5)-, (Rf3PF3)-, BF4-, (RfBF3)-, SO42-, HSO4-, NO3-, F-, Cl-, Br- and/or I-, preferably (RfSO3)-, ((RfSO2)2N)-, ((FSO2)2N)-, ((RfO)2P(O)O)-, RfCOO-, PF6-, BF4-, (RfBF3)-, (B(OR)4)-, (N(CN)2)-, (AlCl4)-, SO42-, HSO4-, NO3, F-, Cl-, Br- or I-, more preferably (RfSO3)-, ((RfSO2)2N)-, ((FSO2)2N)-, ((RfO)2P(O)O)-, RfCOO-, PF6-, BF4-, (RfBF3)-, (B(OR)4)-, (N(CN)2)-, (AlCl4)-, SO42-, HSO4- or NO3, most preferably ((CF3SO2)2N)-, PF6- or BF4-.R=H, halogen, 1-10C alkyl, 2-10C alkenyl having one or more double bond, 2-10C alkynyl having one or more triple bond or cycloalkyl, hydrogen atom of R is optionally substituted by halogen, CN or NO2, carbon atom of R is optionally substituted by -O-, -C(O)-, -C(O)O-, -S-, -S(O)-, -SO2-, -SO3-, -N=, -N=N-, -NR'-, -N(R')2, PR'-, -P(O)R'-, -P(O)R'-O-, -O-P(O)R'-O- or -P(R')2=N-;andRf=fluorine containing substituent.Preferred Process: The ionic liquid is obtained by alkylating sulfur-nitrogen containing compound of formula (2) or (3). Preferred Definitions:    R1-R8=1-20C alkyl or alkoxy, preferably 4-20C alkyl or alkoxy.    At least one of R1-R8 has silyl group.