Question

What impurity(ies) do you think you get rid of in the recrystallization of the product obtained from the synthesis of dimedone?

Answer 1

Synthesis of dimedone can be done by reaction of diethyl malonate and mesityl oxide. In the first step, diethyl malonate in presence of sodium methoxide in MeOH is refluxed, followed by addition of mesityl oxide. In the second and third step, to the product obtained, NaOH is added and again refluxed followed by addition of HCl to obtain the product as a precipitate.

Recrystallization of the product obtained from synthesis, by acetone can remove the unreacted diethyl malonate and final washing by water will remove the traces of acid.