反应详情

To 1 l of concentrated sulfuric acid, 40 g (0.22 mol) of orthonitrophenylacetic acid were added, followed by stirring at 105°-110° C. for 90 minutes. After cooling, 2.5 l of ice water in limited amounts was added to the reaction mixture. The resultant mixture was extracted with if of ethyl ether. The extract was dried over anhydrous sodium sulfate and the solvent was distilled off, so that 18.1 g (yield: 50.2%) of 2,1-benzisoxazole-3-carboxylic acid was obtained as crystals.

1. temperatureAfter cooling
2. extractionThe resultant mixture was extracted with if of ethyl ether
3. dry with materialThe extract was dried over anhydrous sodium sulfate