تفاعل #4267

معادلة التفاعل

diethyl methylmalonate

propargyl bromide

sodium bromide

→

Diethyl 2-methyl-2-propargyl-malonate

المذيبات

ظروف التفاعل

المعالجة

1. 1
   أخرىAt 35° to 40°
2. 2
   workup.STIRRINGthe mixture is stirred for a further hour
3. 3
   أخرىat 45° C
4. 4
   درجة الحرارةThe mixture is refluxed for a further 2 hours
5. 5
   أخرىis separated by suction
6. 6
   ترشيحfiltering
7. 7
   أخرىthe filtrate is substantially evaporated in vacuo
8. 8
   workup.STIRRINGThe residue is stirred into ice water
9. 9
   استخلاصthe aqueous solution is extracted several times with ether
10. 10
    أخرىThe combined organic phases are dried
11. 11
    أخرىevaporated to dryness in vacuo
12. 12
    أخرىThe resulting oil is used in the next stage without any further purification

الإجراء التجريبي

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.

المصدر