反应详情

To a stirred solution of 3-isobutoxy-5-methyl-isoxazole-4-carboxylic acid (146 mg, 0.73 mmol) and triethylamine (74 mg, 0.73 mmol) in tetrahydrofuran (5 mL) at −10° C. and under argon was added ethyl chloroformate (80 mg, 1.46 mmol). After 30 min, the mixture was filtered and the filter cake washed with tetrahydrofuran (4 mL). The combined filtrates were added to a solution of sodium borohydride (69 mg, 1.83 mmol) in water (2 mL) at 5° C. After 2 h the mixture was concentrated in vacuo, diluted with NaOH (2 N, 4 mL) then dried, filtered and concentrated in vacuo to give the title compound (111 mg, 82%) as a pale yellow oil. MS: m/e=186.3 [M+H]+.

1. filtrationthe mixture was filtered
2. washthe filter cake washed with tetrahydrofuran (4 mL)
3. concentrationAfter 2 h the mixture was concentrated in vacuo
4. additiondiluted with NaOH (2 N, 4 mL)
5. customthen dried
6. filtrationfiltered
7. concentrationconcentrated in vacuo