反应详情

16 g of 4-chloro-3-methoxy-2-methylpyridine, 63 g of phenol and 40 g of O-benzylhydroxylamine are stirred at 120° C. under nitrogen for 4 hours. After cooling, the mixture is shaken with 500 ml of 2N NaOH and CH2Cl2. The aqueous phase is extracted a second time with CH2Cl2. After concentrating the combined CH2Cl2 phases, excess O-benzylhydroxylamine is distilled off in vacuo at 0.6 mm. The residue crystallizes on stirring with hexane. After filtering off with suction and washing with hexane 21.6 g=88.4% of product remain. The product is recrystallized from ethyl acetate. M.p.: 130° C.

1. temperatureAfter cooling
2. extractionThe aqueous phase is extracted a second time with CH2Cl2
3. concentrationAfter concentrating the combined CH2Cl2 phases, excess O-benzylhydroxylamine
4. distillationis distilled off in vacuo at 0.6 mm
5. customThe residue crystallizes
6. filtrationAfter filtering off with suction
7. washwashing with hexane 21.6 g=88.4% of product
8. customThe product is recrystallized from ethyl acetate