5817. Meldrum's Acid

Nomenclature

CAS number: 2033-24-1
2,2-Dimethyl-1,3-dioxane-4,6-dione; malonic acid cyclic isopropylidene ester; isopropylidene malonate; 2,2-dimethyl-4,6-diketo-1,3-dioxane.
C6H8O4; mol wt 144.13.
C 50.00%, H 5.59%, O 44.40%.

Description and references

Prepd from malonic acid and acetone in the presence of acetic anhydride: Meldrum, J. Chem. Soc. 93, 598 (1908). Prepn and structure: Davidson, Bernhard, J. Am. Chem. Soc. 70, 3426 (1948); P. Schuster et al., Monatsh. Chem. 95, 53 (1964); G. H. Bihlmayer et al., ibid. 98, 564 (1967). Review: H. McNab, Chem. Soc. Rev. 7, 345-358 (1978).

Chemical structure

Properties

Crystals from acetone + water, dec 94-95°. pKa 5.1.

Use

In organic synthesis as a substitute for acyclic malonic esters and generally as a C3O2 synthon.