Under ice cooling, 2.0 g (12 mmol) of the 4-vinylbenzoyl chloride in methylene chloride was added dropwise to a mixture of 4.2 g (10 mmol) of triphenylsulfonium 1,1-difluoro-2-hydroxyethanesulfonate in Synthesis Example 1-13, 1.21 g (12 mmol) of triethylamine, 0.24 g (2 mmol) of N,N-dimethylaminopyridine, and 20 g of methylene chloride. The resulting mixture was stirred for 2 hours at room temperature. Thereafter, 11 g of 5% dilute hydrochloric acid was added to the reaction mixture. The organic layer was taken out and washed with water, from which methylene chloride was distilled off in vacuum. 30 g of methyl isobutyl ketone was added to the residue, which was washed with dilute aqueous ammonia and then with water. Thereafter, methyl isobutyl ketone was distilled off in vacuum. Diisopropyl ether was added to the residue. By decantation, the target compound, triphenylsulfonium 1,1-difluoro-2-(4-vinyl-benzoyloxy)-ethane-1-sulfonate was obtained. Colorless oil, 5.1 g (yield 86%). The compound has the following structure.
