(E)-3,5-Dichloro-3,5-bis(chloromethyl)-1,2,4-trioxolane

The major crystalline product derived from the ozonolysis of 1,2,3,4-tetrachlorobut-2-ene has been shown to be the monocyclic ozonide title compound, C₄H₄Cl₄O₃, (1), rather than the Z stereoisomer originally reported. The ozonide ring of (1) adopts a half-chair conformation. The molecules pack together to form sheets linked together by a series of ClCl interactions.