反应详情

A solution of 4-amino-5-chloro-2-(2-methoxyethoxy)benzoic acid methyl ester (2.75 g, 10.6 mmoles) 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, and the aqueous solution was extracted with ether (20 ml) and adjusted to pH 4 with concentrated hydrochloric acid (16 ml). A resultant precipitate was filtered, washed with water, air dried, and recrystallized from ethyl acetate to yield 2.03 g (78%) 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. filtrationA resultant precipitate was filtered
5. washwashed with water, air
6. customdried
7. customrecrystallized from ethyl acetate