To a mixture of sodium hydride (50%, 241 mg, 5.0 mmol) and tetrahydrofuran (20 ml) was added 2-[cyclohexyl(methyl)amino]ethanol (791 mg, 5.0 mmol) at 0° C. (external temperature). Then, the reaction mixture was stirred at 60° C. for 30 minutes. After the reaction mixture was cooled at 0° C. (external temperature), to the reaction mixture was added dropwise a solution of tributyl-iodomethyl-tin (2.2 g, 5.0 mmol) in tetrahydrofuran (5 ml), and the reaction mixture was stirred at 60° C. for 1 hour. After the reaction mixture was cooled at room temperature (external temperature), water was added to stop the reaction. Ethyl acetate was added to the reaction mixture, and the organic layer was separated. After the organic layer was washed with water, an aqueous saturated sodium chloride solution, and then, the solvent was distilled off under reduced pressure. The residue was purified by silica gel chromatography (heptane:ethyl acetate=20:1, NH silica gel) to obtain the title compound (790.7 mg, 4.3 mmol, 85%).
