反应详情

Ex-8d) 12.1 g 1-t-Butyloxycarbonylamino-4-chloro-2-butyne is refluxed for 16 h with a mixture of 8 g diethyl acetamidomalonate and sodiumethoxide prepared from 900 mg of sodium in 100 mL of absolute ethanol. Ethanol is then removed under vacuum and the residual mass is partitioned between water and ethylacetate/ether (1:1). The organic layer is treated with 0.5N NaOH and 0.5N HCl and washed with water. It is then dried over Na2SO4, filtered and concentrated. The product is crystallized from ethylacetate/petroleum ether to give ˜7 g of Ethyl-2-acetylamino-6-t-butyloxycarbonylamino-2-ethoxycarbonyl-4-hexynoate.

1. customEthanol is then removed under vacuum
2. customthe residual mass is partitioned between water and ethylacetate/ether (1:1)
3. additionThe organic layer is treated with 0.5N NaOH and 0.5N HCl
4. washwashed with water
5. dry with materialIt is then dried over Na2SO4
6. filtrationfiltered
7. concentrationconcentrated
8. customThe product is crystallized from ethylacetate/petroleum ether