Pentachlorocyclopropane

Pentachlorocyclopropane is a chlorinated cyclopropane with the chemical formula C₃HCl₅. It is a colourless liquid with a faint minty odour. It is thermally unstable above 100 °C; decomposition gives 1,1,3,3,3-pentachloropropene by isomerisation. Pentachlorocyclopropane can be obtained by the addition of dichlorocarbene into trichloroethylene in presence of a base. Pentachlorocyclopropane itself gives tetrachlorocyclopropene when reacted with a base such as potassium hydroxide by means of dehydrohalogenation.