تفاعل #4268

معادلة التفاعل

diethyl 2-methyl-2-propargyl-malonate

potassium hydroxide

→

2-Methyl-2-propargyl-malonic acid

المذيبات

water ethanol

ظروف التفاعل

المعالجة

1. 1
   درجة الحرارةthe mixture is refluxed
2. 2
   أخرىis evaporated to dryness in vacuo
3. 3
   استخلاصextracted several times with methylene chloride
4. 4
   أخرىThe combined extracts are dried
5. 5
   أخرىevaporated to dryness in vacuo
6. 6
   أخرىa colourless product is obtained

الإجراء التجريبي

187 g (0.88 mol) of diethyl 2-methyl-2-propargyl-malonate are added to a solution of 101 g (1.8 mol) of potassium hydroxide in a mixture of 560 ml of water/ethanol (1:1) and the mixture is refluxed with stirring for 2 hours. After the reaction has ended (monitored by TLC) the mixture is evaporated to dryness in vacuo and the residue is then taken up with in water. The aqueous solution is acidified with 50% sulphuric acid and extracted several times with methylene chloride. The combined extracts are dried, evaporated to dryness in vacuo and a colourless product is obtained, m.p. 135° C.

المصدر