反应详情

温度

-78 °C

N-(2-chloroprop-2-enyl)-N-(2-hydroxy-2-phenylethyl)-4-nitrobenzenesulfonamide (1-3, 6.6 g, 16.6 mmol) was dissolved in 40 mL CH2Cl2 and cooled to −78° C. The resulting solution was treated dropwise with conc. H2SO4 (20 mL) and H2O (2 mL). The reaction was placed in a 0° C. bath and stirred 1 h to completion. The reaction was diluted carefully with CH2Cl2 (200 mL) and H2O (400 mL) and the organic layer was separated, dried (MgSO4) and filtered. Concentration of the organic layer followed by flash column chromatography (SiO2, 0-100% EtOAc-hexanes graident over 40 min) provided 1-[(4-nitrophenyl)sulfonyl]-5-phenylpiperidin-3-one (1-4) as a pale yellow solid. 1H NMR (300 MHz, CDCl3) δ 8.39 (d, J=8.8 Hz, 2H), 7.94 (d, J=8.8 Hz, 2H), 7.34 (m, 3H), 7.16 (m, 2H), 4.13 (d, J=15.9 Hz, 1H), 3.98 (m, 1H), 3.42 (d, J=15.9 Hz, 1H), 3.36 (m, 1H), 3.00 (dd, J=12.2, 10.4 Hz, 1H), 2.80 (m, 1H), 2.61 (dd, J=16.2, 11.3 Hz, 1H); MS 361.1 found 361.4 (M+H+) required (ionizes poorly).

1. customwas placed in a 0° C.
2. customthe organic layer was separated
3. dry with materialdried (MgSO4)
4. filtrationfiltered
5. customfollowed by flash column chromatography (SiO2, 0-100% EtOAc-hexanes graident over 40 min)