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Meldrum's acid



Meldrum's Acid
IUPAC name 2,2-Dimethyl-1,3-dioxane-4,6-dione
Identifiers
CAS number 2033-24-1
SMILES O=C(C1)OC(C)(C)OC1=O
Properties
Molecular formula C6H8O4
Molar mass 144.1253 g/mol
Density  ? g/cm3
Melting point

94-96 °C

Boiling point

°C

Except where noted otherwise, data are given for
materials in their standard state
(at 25 °C, 100 kPa)

Infobox disclaimer and references

Meldrum's acid or 2,2-dimethyl-1,3-dioxane-4,6-dione is an organic compound. The main ring structure is a dioxane. The compound was discovered in 1908 by A.N. Meldrum[1] and it is prepared by a condensation reaction of malonic acid with acetone in acetic anhydride with sulfuric acid. Meldrum misidentified[2] the structure as a beta-lactone with a fully fledged carboxylic acid group. Yet Meldrum's acid has a high acidity with a pKa of 4.97, because like ascorbic acid, deprotonation at the methylene next to the carbonyls produces a stable enolate. Because of this property Meldrum's acid like malonic acid is a reactant in Knoevenagel condensations.

References

  1. ^ Meldrum, A. N. J. Chem. Soc. 1908, 93, 598.
  2. ^ The Structure of Meldrum's Supposed beta-Lactonic Acid David Davidson, Sidney A. Bernhard; J. Am. Chem. Soc.; 1948; 70(10); 3426-3428. doi:10.1021/ja01190a060
 
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Meldrum's_acid". A list of authors is available in Wikipedia.
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