反应详情

At 35° to 40° to C., with stirring, 174 g (1.0 ml) of diethyl methylmalonate are added dropwise to an alkoxide solution (prepared from 23 g of sodium and 800 ml of absolute ethanol), the mixture is stirred for a further hour and then at 45° C. 130.8 g (1.1 mol) of propargyl bromide are added dropwise. The mixture is refluxed for a further 2 hours. After cooling the precipitated sodium bromide is separated by suction filtering and the filtrate is substantially evaporated in vacuo. The residue is stirred into ice water and the aqueous solution is extracted several times with ether. The combined organic phases are dried and evaporated to dryness in vacuo. The resulting oil is used in the next stage without any further purification.

1. customAt 35° to 40°
2. stirringthe mixture is stirred for a further hour
3. customat 45° C
4. temperatureThe mixture is refluxed for a further 2 hours
5. customis separated by suction
6. filtrationfiltering
7. customthe filtrate is substantially evaporated in vacuo
8. stirringThe residue is stirred into ice water
9. extractionthe aqueous solution is extracted several times with ether
10. customThe combined organic phases are dried
11. customevaporated to dryness in vacuo
12. customThe resulting oil is used in the next stage without any further purification