Methylene ditosylate (100 mg, 0.28 mmol) and caesium fluoride (213 mg, 1.4 mmol) were dissolved in tert-amyl alcohol (5 mL) and irradiated in a microwave for 15 minutes at 90 °C. The reaction was allowed to cool and the tert-amyl alcohol was removed under reduced pressure, ice-cold diethyl ether was added and the suspension filtered, and then washed with plenty of ice-cold diethyl ether. The filtrate was concentrated under reduced pressure to yield Fluoromethyl 4-Methylbenzenesulfonate as a colourless oil (49 mg, 88% yield).
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