(Diethylamino)sulfur trifluoride → 2-(Trifluoromethoxy)fluorobenzene

Dimethoxyethane (15 ml) was added to the above 3-(4-(2-(3-fluoro-4-trifluoromethoxyphenyl)ethyl)cyclohexyl)propanol (1.52 g, 4.4 mmol), followed by-dropwise adding DAST (1.40 g, 8.7 mmol), refluxing the mixture for 5 hours, extracting the resulting product with toluene, washing the organic layer successively with a saturated aqueous solution of sodium bicarbonate and water, drying over MgSO4, distilling off the solvent, purifying the residue according to column chromatography treatment using heptane as a developing solvent, on silica gel, distilling off the solvent, and recrystallizing the residue from ethanol, to isolate 1-(3-fluoropropyl)cyclohexyl)-3-fluoro-4-trifluoromethoxybenzene (0.12 g, 0.34 mmol). Yield: 7.7%. Its clearing point measured by PERKIN-ELMER 7 series Thermal Analysis System was -5.89° C.