反应详情

温度

25 °C

To a solution of 1′-benzyl-3H-spiro[isobenzofuran-1,4′-piperidin]-3-one 1b (6 g, 20.4 mmol) in dichloromethane (30 mL) was added dropwise 1-chloroethyl chloroformate (2.9 g, 20.4 mmol). The mixture was stirred at 25° C. for 5 hr and then was concentrated to dryness under reduced pressure. The residue was dissolved in methanol and the mixture was heated to reflux for 30 min. The mixture was concentrated to dryness and ether was added. The precipitated solid was collected by filtration and washed with ether, dried in air to obtain 3H-spiro[isobenzofuran-1,4′-piperidin]-3-one 1c as its HCl salt (3.6 g). 1H-NMR (400 MHz, DMSO-d6) δ 9.16 (br, 2H), 7.86-7.81 (m, 2H), 7.63 (t, J=7.6 Hz, 1H), 7.56 (d, J=7.2 Hz, 1H), 3.39-3.42 (m, 2H), 3.11-3.14 (m, 2H), 2.47-2.48 (m, 2H), 1.85 (d, J=14.4 Hz, 2H). MS (ESI) m/z (M+H+): 203.24.

1. concentrationwas concentrated to dryness under reduced pressure
2. dissolutionThe residue was dissolved in methanol
3. temperaturethe mixture was heated
4. temperatureto reflux for 30 min
5. concentrationThe mixture was concentrated to dryness and ether
6. additionwas added
7. filtrationThe precipitated solid was collected by filtration
8. washwashed with ether
9. customdried in air