Reacción #4268

Ecuación de reacción

diethyl 2-methyl-2-propargyl-malonate

potassium hydroxide

→

2-Methyl-2-propargyl-malonic acid

Disolventes

water ethanol

Condiciones de reacción

Tratamiento posterior

1. 1
   Temperaturathe mixture is refluxed
2. 2
   Otrois evaporated to dryness in vacuo
3. 3
   Extracciónextracted several times with methylene chloride
4. 4
   OtroThe combined extracts are dried
5. 5
   Otroevaporated to dryness in vacuo
6. 6
   Otroa colourless product is obtained

Procedimiento

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.

Fuente