反应详情

A solution of 15.9 g of 2,8-bis-(trifluoromethyl)-4-hydroxy-3-quinoline-carboxylic acid chloride in 210 ml of ethyl acetate was added with stirring at 5°-8° C. under nitrogen to a solution of 3.57 g of 2-amino-oxazole and 4.3 g of triethylamine in 50 ml of ethyl acetate and after the temperature returned to room temperature, it stood overnight at that temperature. The mixture was vacuum filtered and the filtrate was washed and evaporated to dryness under reduced pressure. The 14.23 g of residue was triturated with 100 ml of N sodium hydroxide solution for 3 hours and was then diluted with 200 ml of water. The mixture was vacuum filtered and the filtrate was treated with activated carbon. The pH was adjusted to 1 by addition of N hydrochloric acid and the mixture was vacuum filtered. The recovered product was washed with water and dissolved in ethyl acetate. The solution was evaporated to dryness and the 8.77 g of product were crystallized twice from acetic acid to obtain 5.73 g (30.8% yield) of 2,8-bis-(trifluoromethyl)-4-hydroxy-N-(oxazol-2-yl)-3-quinoline-carboxamide melting at 258° C.

1. customreturned to room temperature
2. filtrationfiltered
3. washthe filtrate was washed
4. customevaporated to dryness under reduced pressure
5. customThe 14.23 g of residue was triturated with 100 ml of N sodium hydroxide solution for 3 hours
6. additionwas then diluted with 200 ml of water
7. filtrationfiltered
8. additionthe filtrate was treated with activated carbon
9. additionThe pH was adjusted to 1 by addition of N hydrochloric acid
10. filtrationfiltered
11. washThe recovered product was washed with water
12. dissolutiondissolved in ethyl acetate
13. customThe solution was evaporated to dryness
14. customthe 8.77 g of product were crystallized twice from acetic acid