Tetrachlorocyclopropene is a chemical compound with the formula C3Cl4. A colorless liquid, the compound is a reagent used to prepare acetylene derivatives and in organic synthesis.[1] It is prepared by addition of dichlorocarbene to trichloroethylene.[2] It can react with water and alcohols rapidly.[3]
The compound is used to prepare arylpropiolic acids:
C3Cl4 + ArH + 2 H2O → ArC2CO2H + 4 HCl
Under some circumstances, diarylation occurs, giving diarylcyclopropenones, which decarbonylate to give diarylacetylenes. These reactions are thought to proceed via the intermediacy of trichlorocyclopropenium electrophile (C3Cl3+).