反应详情

To a mixture of 3.0 g (8.76 mmole) of 2-azido-4-(3-trifluoromethyl-phenyl)-thiazole-5-carboxylic acid ethyl ester, 54 mL of tetrahydrofuran was added 3.71 g (88.3 mmole) of lithium hydroxide monohydrate in 36 mL of water. The mixture was stirred at room temperature for 3 hours, and then diluted with 350 mL of diethyl ether. The mixture was extracted three times with 100 mL of water. The combined aqueous layers were acidified by addition of 1M hydrochloric acid, and extracted three times with 100 mL of ethyl acetate. The combined ethyl acetate layers were washed with 50 mL of brine, dried over anhydrous sodium sulfate, filtered and concentrated under reduced pressure to give 2.20 g of 2-azido-4-(3-trifluoromethyl-phenyl)-thiazole-5-carboxylic acid as a yellow-orange solid.

1. extractionThe mixture was extracted three times with 100 mL of water
2. additionThe combined aqueous layers were acidified by addition of 1M hydrochloric acid
3. extractionextracted three times with 100 mL of ethyl acetate
4. washThe combined ethyl acetate layers were washed with 50 mL of brine
5. dry with materialdried over anhydrous sodium sulfate
6. filtrationfiltered
7. concentrationconcentrated under reduced pressure