Base initiated halogen-exchange reactions between perhaloalkanes

Halophilir attacks on C-X bonds (X= Br, Cl) by a base can easily initiate intermolecular brominechlorine exchange reactions either among bromine- or chlorine-conraining perhaloalkane molecules of different compounds or among molecules of the same compound. It provides a new and convenient method to synthesize perhaloalkanes. Apparently, it pertains to an anionic mechanism, i.e. the reaction is initiated by halophilic attack on C-X bonds by the base, and an intermediate carbanion is formed. Distributions of the products depend on the equilibria involving all carbanion intermediates and perhaloalkane product molecules.