反应详情

To a solution of Piperidin-4-yl nitrate hydrochloride (INTERMEDIATE 13, Step B) (0.40 g, 2.20 mmol) and Et3N (0.67 g, 6.60 mmol) in THF/CH3CN 2/1 (24 mL) was added 4-Nitrophenyl chloroformate (0.44 g, 2.20 mmol) as solid. After stirring at rt over night, the mixture was concentrated. The residue was diluted with EtOAc and washed with NaH2PO4 5%. The organic layer was dried over MgSO4 and concentrated. The residue was purified by flash chromatography (Biotage SP1; column SNAP 50; TLC method: n-hexane/ethyl acetate 7/3; Rf=0.37), affording the title product as a white solid. 1H-NMR (300 MHz, CDCl3); δ 8.36-8.25 (2H, m), 7.39-7.28 (2H, m), 5.30-5.18 (1H, m), 4.00-3.50 (4H, m), 2.20-2.06 (2H, m), 2.02-1.86 (2H, m).

1. concentrationthe mixture was concentrated
2. additionThe residue was diluted with EtOAc
3. washwashed with NaH2PO4 5%
4. dry with materialThe organic layer was dried over MgSO4
5. concentrationconcentrated
6. customThe residue was purified by flash chromatography (Biotage SP1; column SNAP 50; TLC method: n-hexane/ethyl acetate 7/3; Rf=0.37)