反应详情

温度

5 °C

To a solution of 6.51 g. (41 mmole) of potassium permanganate in 130 ml. of water and 4.95 ml. of glacial acetic acid, cooled to ca. 5° C., was added a cold (ca. 5° C.) solution of 4.58 g. (21 mmole) of the sodium salt of penicillanic acid in 50 ml. of water. The mixture was stirred at ca. 5° C. for 20 minutes and then the cooling bath was removed. Solid sodium bisulfite was added until the color of the potassium permanganate had been discharged, and then the mixture was filtered. To the aqueous filtrate was added half its volume of saturated sodium chloride solution, and then the pH was adjusted to 1.7. The acidic solution was extracted with ethyl acetate. The extracts were dried, and then evaporated in vacuo, to give 3.47 g. of the title product. The aqueous mother liquor was saturated with sodium chloride, and further extracted with ethyl acetate. The ethyl acetate solution was dried and evaporated in vacuo, to give a further 0.28 g. of product. The total yield was therefore 3.75 g. (78% yield). The NMR spectrum (DMSO-d6) of the product showed absorptions at 1.40 (s,3H), 1.50 (s,3H), 3.13 (d of d's, 1H, J1 =16 Hz, J2 =2 Hz), 3.63 (d of d's, 1H, J1 =16 Hz, J2 =4 Hz), 4.22 (s, 1H) and 5.03 (d of d's, 1H, J1 =4 Hz, J2 =2 Hz) ppm.

1. additionwas added a cold (ca. 5° C.) solution of 4.58 g
2. customthe cooling bath was removed
3. additionSolid sodium bisulfite was added until the color of the potassium permanganate
4. filtrationthe mixture was filtered
5. additionTo the aqueous filtrate was added half its volume of saturated sodium chloride solution
6. extractionThe acidic solution was extracted with ethyl acetate
7. customThe extracts were dried
8. customevaporated in vacuo
9. customto give 3.47 g