反应详情

A solution of 4-amino-5-chloro-2-(2-methoxyethoxy)benzoic acid methyl ester (2.75 g, 10.6 mmol) in 95% ethanol (20 mL) was treated with 50% sodium hydroxide (10 mL) and water (10 mL), and refluxed for one hour. The ethanol was removed in vacuo and replaced with water. The aqueous solution was extracted with ether (20 mL) and acidified to pH 4 with concentrated hydrochloric acid (16 mL). A solid soon precipitated, and this was filtered, washed with water, air dried, and recrystallized from ethyl acetate (2 crops) to afford 2.03 g (75%) of fine pale tan needles; mp 119°-120° C.

1. temperaturerefluxed for one hour
2. customThe ethanol was removed in vacuo
3. extractionThe aqueous solution was extracted with ether (20 mL)
4. customA solid soon precipitated
5. filtrationthis was filtered
6. washwashed with water, air
7. customdried
8. customrecrystallized from ethyl acetate (2 crops)