反应详情

A mixture of 20.6 parts of 1-[(2,3-dihydro-1,4-benzodioxin-2-yl)methyl]-4-(2-methyl-1,3-dioxolan-2-yl)piperidine and 200 parts of a hydrochloric acid solution 2N was stirred and refluxed for 15 hours. After cooling, crushed ice was added. The whole was treated with a sodium hydroxide solution. The product was extracted with dichloromethane. The extract was dried, filtered and evaporated. The residue was purified by column chromatography over silica gel using a mixture of trichloromethane and methanol (99:1 by volume) as eluent. The pure fractions were collected and the eluent was evaporated, yielding 10 parts (55.8%) of 1-[1-[(2,3-dihydro-1,4-benzodioxin-2-yl)methyl]-4-piperidinyl]ethanone as an oily residue (intermediate 87).

1. temperaturerefluxed for 15 hours
2. temperatureAfter cooling
3. customcrushed ice
4. additionwas added
5. extractionThe product was extracted with dichloromethane
6. customThe extract was dried
7. filtrationfiltered
8. customevaporated
9. customThe residue was purified by column chromatography over silica gel using
10. additiona mixture of trichloromethane and methanol (99:1 by volume) as eluent
11. customThe pure fractions were collected
12. customthe eluent was evaporated