Iodine trichloride - heterocyclic base coordination compounds

Abstract

Complexes formed by iodine monochloride and other unipositive iodine compounds with nitrogenous donor molecules have been frequently reported in the literature. There is usually little doubt as to their constitution, the only recorded departures from the stoichiometry I-X: Donor being 2ICl.Py (12) 2I2.Py (I Py2 + I7-), (13, 14) and INO3.Py2 [IPy2 + NO3-] (9) (Py = pyridine). On the other hand those formed by trivalent iodine compounds appear to have been seldom investigated (1, 10, 11). Only IC13: Base complexes have been isolated and these only poorly characterised. In view of the uncertain results so far recorded it seemed desirable to repeat some of their syntheses. The two simplest complexes, i.e. those formed by pyridine and quinoline with iodine trichloride were selected to test the widely differing methods of preparation employed (1, 10, 11) and also if possible to determine the true composition of the products. In addition it was thought wise to use known compounds to gain experience in the techniques of handling these unstable, moisture and heat labile complexes.