反応 #5468

反応方程式

4-amino-5-chloro-2-(2-methoxyethoxy)benzoic acid methyl ester

sodium hydroxide

water

→

fine pale tan needles

収率 78.0%

4-Amino-5-chloro-2-(2-methoxyethoxy)benzoic acid

収率 78.0%

溶媒

ethanol

反応条件

後処理

1. 1
   温度refluxed for one hour
2. 2
   その他The ethanol was removed in vacuo
3. 3
   抽出The aqueous solution was extracted with ether (20 mL)
4. 4
   その他A solid soon precipitated
5. 5
   ろ過this was filtered
6. 6
   洗浄washed with water, air
7. 7
   その他dried
8. 8
   その他recrystallized from ethyl acetate (2 crops)

実験手順

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.

出典