反应详情

温度

45 °C

Sodium hydroxide (0.58 g, 0.0145 mol) in water is added to a solution of methyl 2,3-dimethyl-2-[(1-oxo-2,3-benzoxazin-4-yl)amino]butyrate (2.0 g, 0.00689 mol) and tetrahydrofuran under a nitrogen atmosphere. The reaction mixture is stirred at 45° C. for 36 hours then at room temperature for 6 days. The reaction mixture is concentrated in vacuo to give an oil. The oil is dissolved into water. The aqueous solution is cooled with an ice-bath and concentrated sulfuric acid is added until a pH of about 1 is obtained then the solution is extracted with ethyl acetate. The combined ethyl acetate extracts are dried with anhydrous magnesium sulfate and concentrated in vacuo to give a pale yellow solid. The solid is added to boiling methylene chloride and after 2/3 of the methylene chloride has evaporated, the mixture is filtered to give the title compound as a white solid (1.44 g, 76%), mp 186°-188° C., identified by IR and NMR spectral analyses.

1. waitat room temperature for 6 days
2. concentrationThe reaction mixture is concentrated in vacuo
3. customto give an oil
4. temperatureThe aqueous solution is cooled with an ice-bath
5. customis obtained
6. extractionthe solution is extracted with ethyl acetate
7. dry with materialThe combined ethyl acetate extracts are dried with anhydrous magnesium sulfate
8. concentrationconcentrated in vacuo
9. customto give a pale yellow solid
10. additionThe solid is added
11. customafter 2/3 of the methylene chloride has evaporated
12. filtrationthe mixture is filtered