Реакция #4267

Уравнение реакции

diethyl methylmalonate

propargyl bromide

sodium bromide

→

Diethyl 2-methyl-2-propargyl-malonate

Растворители

Условия реакции

Обработка

1. 1
   ДругоеAt 35° to 40°
2. 2
   workup.STIRRINGthe mixture is stirred for a further hour
3. 3
   Другоеat 45° C
4. 4
   ТемператураThe mixture is refluxed for a further 2 hours
5. 5
   Другоеis separated by suction
6. 6
   Фильтрацияfiltering
7. 7
   Другоеthe filtrate is substantially evaporated in vacuo
8. 8
   workup.STIRRINGThe residue is stirred into ice water
9. 9
   Экстракцияthe aqueous solution is extracted several times with ether
10. 10
    ДругоеThe combined organic phases are dried
11. 11
    Другоеevaporated to dryness in vacuo
12. 12
    ДругоеThe resulting oil is used in the next stage without any further purification

Методика

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.

Источник