To a solution of 4-hydroxymethylcyclohexanol (2 mmol) in 10 mL of tetrahydrofuran (THF) was added CDI (2.2 mmol) and the resulting mixture was stirred for 2 hours at room temperature. Then, pyrrolidine (3 mmol) was added and stirred for 2 hours at 60° C. The reaction mixture was diluted with water, followed by few times of extraction with methylene chloride. The combined organic layer was dried over anhydrous magnesium sulfate, filtered and concentrated under reduced pressure. The residue was purified by column chromatography (silica gel, hexane:ethyl acetate=1:1) to provide a intermediate compound. The intermediate compound was dissolved in acetonitrile (10 mL), and CDI (2.2 mmol) was added. After 1 hour stirring at 80° C., methyl iodide (10 mmol) was added and stirred for additional 1 hour at 80° C. The resulting reaction mixture was concentrated under reduced pressure. The residue was dissolved in acetonitrile (10 mL), and phenethylamine (3 mmol) was added and stirred for 4 hours at 80° C. The reaction mixture was diluted with water, followed by few times of extraction with methylene chloride. The combined organic layer was dried over anhydrous magnesium sulfate, filtered and concentrated under reduced pressure. The residue was purified by column chromatography (silica gel, hexane:ethyl acetate=1:3), thereby completing the preparation of a target compound (411 mg, 55% yield).
