Complexation par transfert de charge de la chlorpromazine en présence d'iode; action thyroïdienne sécondaire de cette molécule

Molecular interaction between iodine and chlorpromazine is investigated by electron spectroscopy. Iodine forms a charge transfer complex with chlorpromazine, with 1:1 stoichiometry and of the n–σ type. The values of the formation constant (Kc at20 °C = 3166 ± 19 L mol−1) and thermodynamic parameters (ΔH0 = −11.22 ± 0.11 kcal mol−1, ΔS0 = −22.29 ± 0.38 cal mol−1 K−1) show a strong donor–acceptor interaction, comparable to that obtained with tertiary amines. The formation constant is compared to those obtained with antithyroid molecules. Chlorpromazine appears to have no effect on the intrathyroid cycle of iodine.