To a mixture of 7.39 g (0.015 mole) of triphenylsulfonium 2-hydroxy-1,1,3,3,3-pentafluoropropane-1-sulfonate, 2.33 g (0.017 mole) of chlorobutyric chloride, and 37 g of acetonitrile, 1.42 g (0.018 mole) of pyridine was added dropwise, followed by stirring at room temperature for 3 hours. Then 18 g of 5% dilute hydrochloric acid was added to the reaction solution whereupon acetonitrile was distilled off under vacuum. The residue was combined with 40 g of dichloromethane whereupon the organic layer was separated. The organic layer was washed with 30 g of water, from which dichloromethane was distilled off under vacuum. To the residue was added 40 g of methyl isobutyl ketone. This was washed with 30 g of water, with 30 g of dilute aqueous ammonia, and three times with 30 g of water whereupon methyl isobutyl ketone was distilled off under vacuum. Ether was added to the residue, followed by decantation and vacuum drying. The target compound was obtained as brown oil (7.94 g, yield 87%).
