Nomenclature
CAS number: 504-64-3
1,2-Propadiene-1,3-dione; tricarbon dioxide.
C
3O
2; mol wt 68.03.
C 52.97%, O 47.04%.
O=C=C=C=O.
Description and references
Prepn by thermal decompn of malonic acid:
Glemser in Handbook of Preparative Inorganic
Chemistry vol. 1, G. Brauer, Ed. (Academic
Press, New York, 2nd ed., 1963) p 648. Reactions in organic synthesis:
Dashkevich, Beilin, Russ. Chem. Rev. 36, 391 (1967). Comprehensive reviews: Reyerson, Kobe, Chem. Rev. 7, 479 (1930); Vol'kenshtein, Usp. Khim. 4, 610 (1935); Grauer, Chimia 14, 11 (1960); T. Kappe,
E. Ziegler, Angew. Chem. Int. Ed. 13, 491-504 (1974), reprinted in New Synthetic Methods vol. 1 (Verlag Chemie,
Weinheim, 1975) pp 29-69.
Properties
Colorless, highly refractive liquid or colorless
gas which burns with a blue, sooty flame. Odor like acrolein and
mustard oil. mp -111.3°. bp760 6.8°. d40 1.114. n0D 1.45384; nD-12 1.46757. Vapor pressure at 0°: 587-589 mm. Explosive limits, 6
to 30 vol % in air. Dipole moment: 0.7D. Thermodynamic constants:
Thompson, Trans. Faraday Soc. 37, 249 (1941). The gas can be stored at pressures of
up to 100 mm, but even at these pressures polymerization may occur,
giving a red, water-sol product. This invariably occurs at higher
pressure or in the liquid state. Polymerization facilitated by presence
of P2O5. Dec when passed through heated glass
tubes, forming a mirror surface. Difficultly sol in carbon disulfide,
xylene. With water forms malonic acid quantitatively. Forms malonamide
with ammonia.Caution
In small amounts acts as a lacrimator;
in high concns attacks eyes, nose, respiratory organs, producing a
feeling of suffocation.Use
Prepn of malonates; improving dye affinity of fibers.