反应详情

6.38 g of acetyl chloride (0.081 mol) are added dropwise to a mixture of 65 ml of methanol and 65 ml of acetone. 5.2 g (0.032 mol) of benzofuran-2,3-dione 2-oxime are dissolved in this mixture, and the mixture is subsequently heated under reflux for 1 hour. The solvent is distilled off under reduced pressure, the residue is poured into water, the product is extracted with diethyl ether, the organic phase is dried over sodium sulphate and the solvent is distilled off under reduced pressure. This gives 5.2 g of crude product which is chromatographed over silica gel using a mixture of 7 parts n-hexane and 3 parts acetone. This gives 3.8 g of a product which, according to HPLC, contains 88% of methyl 2-hydroxyphenylglyoxylate of log p=1.87.

1. temperaturethe mixture is subsequently heated
2. temperatureunder reflux for 1 hour
3. distillationThe solvent is distilled off under reduced pressure
4. additionthe residue is poured into water
5. extractionthe product is extracted with diethyl ether
6. dry with materialthe organic phase is dried over sodium sulphate
7. distillationthe solvent is distilled off under reduced pressure
8. customThis gives 5.2 g of crude product which is chromatographed over silica gel using
9. additiona mixture of 7 parts n-hexane and 3 parts acetone