Patent ID: 7709548

Claim:
A method for manufacturing a monosulfonium salt represented by the general formula (1): wherein Ar denotes an optionally substituted aryl group; each of R 1 and R 2 denotes the same or different, optionally substituted heterocyclic group or hydrocarbon group; and X − denotes BF 4 − , PF 6 − , AsF 6 − , or SbF 6 − , which comprises introducing (a) an aryl compound, (b) a sulfoxide compound, (c) a dehydrating agent, and (d) a BF 4 , PF 6 , AsF 6 , or SbF 6 salt of an alkali metal or an alkaline earth metal into a reaction system, followed by introduction of (e) an inorganic acid so that the aryl compound (a) and the sulfoxide compound (b) are subjected to dehydration condensation.