反应详情

A mixture of 25 parts of 5-chloro-2-nitrobenzenemethanol, 13.3 parts of dihydro-2H-pyran, 300 parts of dichloromethane and 0.28 parts of 4-methylbenzenesulfonic acid was stirred for 2 hours at reflux temperature. After cooling, the reaction mixture was neutralized with sodium carbonate and stirred for 10 min. The whole was filtered and the filtrate was evaporated. The residue was co-evaporated with methylbenzene and then purified by columns chromatography (silica gel; CHCl3). The eluent of the desired fraction was evaporated and the residue was co-evaporated with methylbenzene, yielding 36 parts (99.6%) of 2-[(5-chloro-2-nitrophenyl)methoxy]tetrahydro-2H-pyran (interm. 1).

1. temperatureat reflux temperature
2. temperatureAfter cooling
3. stirringstirred for 10 min
4. filtrationThe whole was filtered
5. customthe filtrate was evaporated
6. custompurified by columns chromatography (silica gel; CHCl3)
7. customThe eluent of the desired fraction was evaporated