Chemfm cyclopropanetrione.svg
IUPAC name
  • 76719-55-6
3D model (JSmol)
  • Interactive image
  • 35786973
  • 58556001
  • DTXSID50729390 Edit this at Wikidata
  • InChI=1S/C3O3/c4-1-2(5)3(1)6
  • InChI=1/C3O3/c4-1-2(5)3(1)6
  • O=C1C(=O)C1=O
Molar mass 84.03 g/mol
Related compounds
Related compounds
deltic acid oxopropandial
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

Cyclopropanetrione or trioxocyclopropane is a little-known oxide of carbon with formula C3O3. It consists of a ring of three carbon atoms each attached to an oxygen atom with a double bond. Alternately it can be thought as a trimer of carbon monoxide. This compound is thermodynamically unstable[why?][how?], and has not been produced in bulk.[1] However it has been detected using mass spectrometry.[2][3]

It is the neutral equivalent of the deltate anion C3O32−, known since 1975.[4] An equivalent hydrate hexahydroxycyclopropane or cyclopropane-1,1,2,2,3,3-hexol, (-C(OH)2-)3 also exists. This contains geminal hydroxy groups.[5]


  1. ^ Corkran, Greg; David W. Ball (2004). "The relative energies of cyclopropanone, cyclopropanedione, and cyclopropanetrione. Hartree–Fock, density-functional, G2, and CBS calculations". Journal of Molecular Structure: THEOCHEM. 668 (2–3): 171–178. doi:10.1016/j.theochem.2003.10.026. ISSN 0166-1280.
  2. ^ Schröder, Detlef; Helmut Schwarz; Suresh Dua; Stephen J. Blanksby; John H. Bowie (1999). "Mass spectrometric studies of the oxocarbons CnOn (n = 3–6)". International Journal of Mass Spectrometry. 188 (1–2): 17–25. Bibcode:1999IJMSp.188...17S. doi:10.1016/S1387-3806(98)14208-2. ISSN 1387-3806.
  3. ^ Eggerding, David; Robert West (1975). "Synthesis of dihydroxycyclopropenone (deltic acid)". Journal of the American Chemical Society. 97 (1): 207–208. doi:10.1021/ja00834a047. ISSN 0002-7863.
  4. ^ Eggerding, David; Robert West (1976). "Synthesis and properties of deltic acid (dihydroxycyclopropenone) and the deltate ion". Journal of the American Chemical Society. 98 (12): 3641–3644. doi:10.1021/ja00428a043. ISSN 0002-7863.
  5. ^ Skujins, S.; J. Delderfield, G.A. Webb (1968). "A mass spectrometric study of some monocyclic polycarbonyl compounds". Tetrahedron. 24 (13): 4805–4817. doi:10.1016/S0040-4020(01)98676-4. ISSN 0040-4020.