C-13 NUCLEAR-MAGNETIC-RESONANCE STUDIES OF THE REDOX REACTIONS OF AUROTHIOMALATES WITH SELENOCYANATE IN AQUEOUS-SOLUTION

The interactions of SCN- and SeCN- with aurothiomalate [Au(tm)](n) in aqueous solution were studied by C-13 NMR spectroscopy. The [Au(tm)](n ) is further polymerized in the presence of SCN-, however, SeCN- binds to [Au(tm)](n) forming monomeric [Au(SeCN)(tm)](-). This complex Init ially disproportionates to give [Au(SeCN)(2)](-) and [Au(tm)(2)](-). T he [Au(SeCN)(2)](-) eventually decomposed to give [Au(CN)(2)](-) and m etallic selenium. The free tm(-) released from [Au(tm)](n) is oxidized to the thiomalic disulfide (tm)(2). When the bis complex [Au(tm)(2)]( -) reacted with SeCN- it did not form [Au(SeCN)(tm)](-), but instead g ave(tm)(2), [AU(CN)(2)](-) and Se-2(2-).