反応 #42497

反応方程式

methyl 4-butyl-3,4-dihydro-2H-1,4-benzoxazine-6-carboxylate

potassium hydroxide

→

title compound

収率 98.8%

4-Butyl-3,4-dihydro-2H-1,4-benzoxazine-6-carboxylic acid

収率 98.8%

溶媒

methanol

反応条件

後処理

1. 1
   濃縮concentrated under reduced pressure
2. 2
   workup.ADDITIONThe residue was diluted with water
3. 3
   洗浄washed with ethyl acetate
4. 4
   抽出extracted with chloroform (4×50 mL)
5. 5
   乾燥The combined organic extracts were dried (sodium sulfate)
6. 6
   ろ過filtered
7. 7
   濃縮concentrated under reduced pressure

実験手順

To a stirred solution of methyl 4-butyl-3,4-dihydro-2H-1,4-benzoxazine-6-carboxylate (412 mg) in methanol (5 mL) was added 1 M potassium hydroxide (17 mL). The mixture was stirred at room temperature for 5 h and concentrated under reduced pressure. The residue was diluted with water and washed with ethyl acetate. The aqueous layer was acidified to pH 4 with 1 N hydrochloric acid and extracted with chloroform (4×50 mL). The combined organic extracts were dried (sodium sulfate), filtered, and concentrated under reduced pressure to provide 384 mg of the title compound: ESI MS m/z 236 [M+H]+.

出典