The Binuclear Peroxo Complex Compounds of Tri- and Tetrapositive Cobalt

Abstract

BINUCLEAR PEROXO COMPLEX COMPOUNDS OF COBALT 5 trichlorothorium ions. However, with additional data it has become apparent that while the monoand trichloro ions are the predominant chlorothorium species at all concentrations up to 4 M chloride the di-and tetrachlorothorium species are present in measurable concentration. Table I1 illustrates the relative importance, percentagewise, of the thorium species in 1, 2 and 4 M chloride solution at an ionic strength of four. = 0.00-1.96 M ; [H+] = 0.04 M ; [CIO-] = 0.04;-2.00A repetition of the preparative work of A. Werner and others confirmed the existence of a series of green binuclear peroso compounds containing a cobalt atom in the tetrapositive oxidation state. A second series of red com ounds which Werner, using the conce t of secondary valence forces formulated as isomers proved to be the one electron refuction products of the green series a n f contained only tripositive cobalt. Analytically, the red compounds a peared to be isomeric because, while they are only weakly basic in solution, they normally precipitate as acid salts and tgus differ from the green series by a single proton. The reported ''isomeric conversions" are in reality all oxidation-reduction reactions and include the bromidecatalyzed disproportionation of the red series and reduction of the green series by hydroxide ion.

Stereochemistry and Reaction Mechanisms of Hexacovalent Inorganic Complexes.

“…Except for the fact that three equivalents of oxygen are liberated per mole of C, all of the present available data can just as well be explained on the basis of a superoxide ion type of structure (118). The exact structure of these compounds is therefore not known, but some attempt is being made to clarify this problem (207).…”

“…Several reactions were carried out on the dark green Z-D and in every case a red to brown dextrorotatory product was obtained. For example, if ammonia is allowed to react with Z-D, the product has a specific rotation of Thompson and Wilmarth (207) have recently made an excellent beginning toward a definite elucidation of the structure of these compounds. They were able to show that the change of the dark green complex D into the red compounds reported by Werner involved a one-electron reduction.…”