Réaction #4268

Équation de réaction

diethyl 2-methyl-2-propargyl-malonate

potassium hydroxide

→

2-Methyl-2-propargyl-malonic acid

Solvants

water ethanol

Conditions de réaction

Traitement

1. 1
   Températurethe mixture is refluxed
2. 2
   Autreis evaporated to dryness in vacuo
3. 3
   Extractionextracted several times with methylene chloride
4. 4
   AutreThe combined extracts are dried
5. 5
   Autreevaporated to dryness in vacuo
6. 6
   Autrea colourless product is obtained

Mode opératoire

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.

Source