反应详情

To a mixture of 2.44 g (7.14 mmole) of 2-azido-4-(4-trifluoromethyl-phenyl)-thiazole-5-carboxylic acid ethyl ester and 45 mL of tetrahydrofuran was added, 3.01 g (71.5 mmole) of lithium hydroxide monohydrate in 33 mL of water. The mixture was stirred at room temperature for 17 hours and then diluted with 300 mL of diethyl ether. The ether layer was extracted three times with 100 mL of water. The combined aqueous phases were acidified by the 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 1.76 g of 2-azido-4-(4-trifluoromethyl-phenyl)-thiazole-5-carboxylic acid as a light yellow solid.

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