反应详情

8.2 g (0.05 mol) of benzofuran-2,3-dione 2-oxime and 9 g (0.108 mol) of O-methylhydroxylamine hydrochloride in 50 ml of methanol are heated under reflux for 3 hours. The methanol is distilled off under reduced pressure and the residue is mixed with 50 ml of water and extracted with ethyl acetate. The organic phase is dried over sodium sulphate and the solvent is distilled off under reduced pressure, giving 9.88 g of crystal-containing crude product. According to HPLC, the crude product contains 43.7% of methyl E-2-(2-hydroxyphenyl)-2-methoxyimino-acetate of log p=1.48 and 29.4% of methyl Z-2-(2-hydroxyphenyl)-2-methoxyimino-acetate of log p=2.37.

1. temperatureunder reflux for 3 hours
2. distillationThe methanol is distilled off under reduced pressure
3. additionthe residue is mixed with 50 ml of water
4. extractionextracted with ethyl acetate
5. dry with materialThe organic phase is dried over sodium sulphate
6. distillationthe solvent is distilled off under reduced pressure
7. customgiving 9.88 g
8. additionof crystal-containing crude product