Etude de la protolyse du cryptate d'iode positif

The diprotonated cryptand ∣2.2.2 H₂∣²⁺ is formed by the addition in nitromethane 1 of two equivalent of trifluoroacetic acid (or hydroiodic acid) to the cryptate ∣2.2.2 I∣⁺, I^?; the reaction is accompanied by the release of molecular iodine. Upon adding only one equivalent of trifluoroacetic acid, no release of iodine is observed and the formation of complex ∣H - 2.2.2- I∣²⁺ is deduced from NMR, UV and conductance measurements.