反应详情

3.3 g (0.016 mol) of methyl 2-hydroxyphenylglyoxylate (HPLC: 88%, log p=1.87) (Example VI-1a) and 1.3 g (0.019 mol) of hydroxylamine hydrochloride in 50 ml of methanol are heated under reflux for one hour. The reaction mixture is poured into water, acidified with 2N hydrochloric acid and extracted with diethyl ether, the organic phase is dried over sodium sulphate and the solvent is distilled off under reduced pressure. This gives 2.4 g of crude product which, according to HPLC, contains 17.1% of methyl E-2-(2-hydroxyphenyl)-2-hydroxyimino-acetate of log p=0.95 and 68.9% of methyl Z-2-(2-hydroxyphenyl)-2-hydroxyimino-acetate of log p=1.68.

1. temperatureunder reflux for one hour
2. extractionextracted with diethyl ether
3. dry with materialthe organic phase is dried over sodium sulphate
4. distillationthe solvent is distilled off under reduced pressure