Process for producing triarylsulfonium salt

摘要

[Subject] To provide a method for effectively producing a triarylsulfonium salt having a structure that only one aromatic ring of three aromatic rings on the cation portion thereof is different from the other two aromatic rings (hereinafter, abbreviated as a triarylsulfonium salt relating to the present invention) in a high yield without forming any byproduct. [Means for Solution Problems] The present invention relates to a method for producing a triarylsulfonium salt represented by the general formula [4]: wherein, two R¹'s represent each hydrogen atom, halogen atom, alkyl group, lower haloalkyl group, alkoxy group, acyl group, hydroxyl group, amino group, nitro group or cyano group; R represents an aryl group which may have a substituent selected from a halogen atom, an alkyl group, a lower haloalkyl group, an alkoxy group, an alkylthio group, a N-alkylcarbamoyl group and a carbamoyl group, and the above substituent is different from one represented by the above R¹; and A₁ represents a strong acid residue, comprising reacting a diaryl sulfoxide represented by the general formula [1]: wherein, R¹ represents the same as above, and an aryl Grignard reagent represented by the general formula [2]: RMgX [2] wherein, X represents a halogen atom; R represents the same as above, in the presence of an activator with high affinity for oxygen of 3 to 7.5 equivalents relative to the above diaryl sulfoxide, and then reacting the resultant reaction mixture with a strong acid represented by the general formula [3]: HA₁ [3] wherein, A₁ represents the same as above, or a salt thereof.