Etude electrochimique de l'iode et du brome en presence de cryptands

In presence of cryptands ([2.2.2], [2.2.1] and [2.1.1]) halogens X₂(bromide and iodine) give rise to the formation of an halonium ion complex in chloroformic solution. Preliminary voltammetric studies of halide and halogen alone allow to measure the stability constant of the trimeric X₃^? species in this solvent. By calculation it is then possible to determine the constant ratio: [cryptand —I⁺] [I₂]^?1 [cryptand]^?1 for iodine only, which is supposed to be a ratio fo the kinetic constants of formation and decomplexation of the halonium complexe.