反应详情

4.27 ml (0.08 mol; 1.20 V) of sulfuric acid diluted in 4.3 ml of water were added dropwise to 3.56 g of 2-tert-butyl-6-chloro-7-(4-methylpiperazine-1-sulfonyl)benzooxazole (0.01 mol; 1.0 eq) in solution in 15 ml of 1,4-dioxane. The reaction medium was refluxed for six and a half hours. The reaction medium was concentrated and 1 N sodium hydroxide was added (to pH 7). The solution was extracted with dichloromethane. The organic phases were combined, dried over magnesium sulfate, filtered and evaporated. The residue obtained was chromatographed on silica gel, eluent 95/5 ethyl acetate/dichloromethane. 2.0 g of 6-amino-3-chloro-2-(4-methylpiperazine- 1-sulfonyl)phenol were obtained in the form of a thick brown oil. Yield=68%.

1. temperatureThe reaction medium was refluxed for six and a half hours
2. concentrationThe reaction medium was concentrated
3. addition1 N sodium hydroxide was added (to pH 7)
4. extractionThe solution was extracted with dichloromethane
5. dry with materialdried over magnesium sulfate
6. filtrationfiltered
7. customevaporated
8. customThe residue obtained
9. customwas chromatographed on silica gel, eluent 95/5 ethyl acetate/dichloromethane