Azeotropic transesterification of beta-keto esters

Transesterifications of methyl P-keto carboxylates catalyzed by DMAP with v arious high boiling alcohols can be accomplished in refluxing cyclohexane i n a Dean-Stark trap. The MeOH formed is removed completely from the reactio n mixture as an azeotrope leading to quantitative conversions. The starting materials are converted in stoichiometric ratio, which makes the purificat ion of the product very simple and results in high yields.