Meldrum's acid

2,2-dimethyl- 1 ,3-dioxane -4 ,6- dione

Fixed

92-96 ° C

4.97

Template: Infobox chemical / molecular formula search available

Meldrum's acid is an organic compound, which is named after its discoverer Andrew Norman Meldrum. It was first produced in 1908 in the presence of sulfuric acid by condensation of malonic acid with acetone in acetic anhydride. As Meldrum initially originated by a β - lactone with a free carboxyl group, the compound is erroneously referred to as an acid. The structure was then corrected in 1948.

Meldrum's acid has a comparatively high CH - acidity with a pKa of 4.97. The analog malonate however has only a pKa of about 13. It was only in 2004, this phenomenon could be explained by theoretical calculations.

Because of their high CH- acidity of Meldrum's acid reacts, like malonic acid, with carbonyl compounds in a Knoevenagel condensation. With carboxylic acid chlorides it reacts in the presence of pyridine to the acyl Meldrum's acid. If this heated in alcohols, produced a β -keto ester. Meldrum's acid is thus a starting compound for the synthesis of this class of substances. The β -keto esters are used in the Knorr pyrrole used.