反应详情

3,6-Difluoro-2-(4-ethoxycarbonyl-1-piperazinyl)-5-nitrobenzyl alcohol (7.14 g) is dissolved in methanol (770 ml), and thereto is added dropwise conc. sulfuric acid (145 ml) while cooling on an ice bath. The mixture is refluxed for 4 hours. The reaction mixture is cooled to room temperature and is poured into ice water (1.5 liter), and then extracted with dichloromethane. The extract is dried over magnesium sulfate and sodium sulfate, and then the solvent is distilled off under reduced pressure to give 3-methoxymethyl-2,5-difluoro-4-(4-ethoxycarbonyl-1-piperazinyl)nitrobenzene (7.39 g) as yellow powder, m.p. 85°-86° C.

1. temperaturewhile cooling on an ice bath
2. temperatureThe mixture is refluxed for 4 hours
3. extractionextracted with dichloromethane
4. dry with materialThe extract is dried over magnesium sulfate and sodium sulfate
5. distillationthe solvent is distilled off under reduced pressure