反应详情

温度

-10 °C

To a solution of 3-(3-chloro-phenyl)-5-methyl-isoxazole-4-carboxylic acid (4.8 g, 20 mmol in THF (50 mL) at −10° C. was added triethylamine (2.9 mL, 21 mmol) and then a solution of ethylchloroformate (1.96 mL, 20 mmol) in THF (10 mL) added keeping the temperature below −5° C. After 1 h the mixture was filtered and the filtrate cooled to −10° C. and a suspension of sodiumborohydride (2.0 g, 50 mmol) in water (10 mL) added over 15 minutes keeping the temperature below −5° C. The mixture was then allowed to warm up to room temperature over 2 h and diluted with sodium hydroxide (2 N, 30 mL) and extracted with ethyl acetate. The combined organic layers were then washed with water and brine, dried over sodium sulfate and evaporated to afford the title compound (3.5 g, 78%) which was obtained as a clear oil which solidified with time as a white solid. Mp: 66-68° C.

1. customthe temperature below −5° C
2. filtrationAfter 1 h the mixture was filtered
3. additionadded over 15 minutes
4. customthe temperature below −5° C
5. temperatureto warm up to room temperature over 2 h
6. extractionextracted with ethyl acetate
7. washThe combined organic layers were then washed with water and brine
8. dry with materialdried over sodium sulfate
9. customevaporated