反应详情

To a solution of 4-((1R,2S)-2-{2-{4-(ethylsulfonyl)-3-fluorophenoxy]ethyl}cyclopropyl)piperidine-1-carbonitrile (Step D; 100 mg, 0.27 mmol) and N-hydroxy-2-methoxyacetimidamide (38 mg, 0.37 mmol) in tetrahydrofuran (5 mL) was added zinc chloride (0.8 mL, 0.5 M in tetrahydrofuran, 0.4 mmol). The mixture was refluxed for 2 h, cooled to RT, and concentrated to dryness under reduced pressure. The residue was dissolved in 2 mL of 4N HCl ethanol and water (1:1). The solution was refluxed for 30 min, cooled to RT, and concentrated to dryness under reduced pressure. The residue was dissolved in methanol (5 mL), neutralized by the addition of excess potassium carbonate, mixed silica gel (2 g), and concentrated to dryness under reduced pressure. The residue was loaded on a silica gel column (10 g of silica gel) and eluted with a gradient of dichloromethane/CMA, 19:1, 500 mL; 4:1, 500 mL to provide the title compound. MS (ESI) m/z 468 [M+H]+.

1. temperatureThe mixture was refluxed for 2 h
2. concentrationconcentrated to dryness under reduced pressure
3. dissolutionThe residue was dissolved in 2 mL of 4N HCl ethanol
4. temperatureThe solution was refluxed for 30 min
5. temperaturecooled to RT
6. concentrationconcentrated to dryness under reduced pressure
7. dissolutionThe residue was dissolved in methanol (5 mL)
8. additionneutralized by the addition of excess potassium carbonate
9. additionmixed silica gel (2 g)
10. concentrationconcentrated to dryness under reduced pressure
11. washeluted with a gradient of dichloromethane/CMA, 19:1, 500 mL