Cyclopropanetrione

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 predicted to be thermodynamically unstable, dissociating to carbon monoxide,^[1] and has not been produced in bulk. However, C₃O₃ molecules, provisionally assigned to either cyclopropanetrione or its open-chain analog •(CO)₃•, have been detected using mass spectrometry.^[2]

Cyclopropanetrione

Names
IUPAC name cyclopropane-1,2,3-trione
Identifiers
CAS Number	76719-55-6
3D model (JSmol)	Interactive image
ChemSpider	35786973
PubChem CID	58556001
CompTox Dashboard (EPA)	DTXSID50729390
InChI InChI=1S/C3O3/c4-1-2(5)3(1)6 Key: RONYDRNIQQTADL-UHFFFAOYSA-N InChI=1/C3O3/c4-1-2(5)3(1)6 Key: RONYDRNIQQTADL-UHFFFAOYAP
SMILES O=C1C(=O)C1=O
Properties
Chemical formula	C3O3
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

It is the neutral equivalent of the deltate anion C₃O₃²⁻, known since 1975.^[3][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]