反应详情

To a solution of 2,5,6-trichlorobenzimidazole (2.07 g, 9.33 mmol) in tetrahydrofuran (20 mL) were added 3,4-dihydro-2H-pyran (2.55 mL, 28.0 mmol) and camphor sulfonic acid (216 mg, 0.93 mmol). The mixture was stirred at room temperature for 3 hours, and the reaction mixture was neutralized by addition of 0.1M aqueous sodium hydroxide, then extracted with ethyl acetate. The organic layer was washed with saturated brine, dried over anhydrous sodium sulfate, and concentrated in vacuo. The residue was purified by silica gel column chromatography (C-300, hexane:ethyl acetate=4:1) to give the title compound (487 mg, 9%).

1. extractionextracted with ethyl acetate
2. washThe organic layer was washed with saturated brine
3. dry with materialdried over anhydrous sodium sulfate
4. concentrationconcentrated in vacuo
5. customThe residue was purified by silica gel column chromatography (C-300, hexane:ethyl acetate=4:1)