反应详情

A mixture of 4-(6-fluoro-1,2-benzisoxazol-3-yl)piperidine (7.45 g, 33.4 mmol), K2CO3 (5.5 g) and bromo-2,2-dimethoxypropane (6.84 g, 37.6 mmol) in acetonitrile (200 ml) was heated and stirred at reflux for 4 hours. An additional charge of bromo-2,2-dimethoxypropane (5.1 g, 28 mmol) was added and the mixture was refluxed overnight. After being cooled to room temperature, the mixture was filtered, and the solvent was removed on a rotary evaporator. The residue was purified by flash chromatography over a silica gel column (SiO2, 100 g; eluted with dichloromethane, DCM, and 1% CH3OH in DCM). The oil product thus obtained weighed 2.2 g (24%). The oil product was dissolved into ethanol (10 ml) then was treated with HCl in ether solution (1M, 9 ml) at room temperature. The crystals were collected, 2.08 g, m.p.=220°-223° C. dec.

1. temperaturewas heated
2. temperatureat reflux for 4 hours
3. additionwas added
4. temperaturethe mixture was refluxed overnight
5. filtrationthe mixture was filtered
6. customthe solvent was removed on a rotary evaporator
7. customThe residue was purified by flash chromatography over a silica gel column (SiO2, 100 g; eluted with dichloromethane, DCM, and 1% CH3OH in DCM)
8. customThe oil product thus obtained
9. customThe crystals were collected