HOMOLEPTIC SILVER(I) COMPLEXES WITH DITHIO-ETHERS, DISELENO-ETHERS AND DITELLURO-ETHERS - SYNTHESIS, STRUCTURES AND MULTINUCLEAR NUCLEAR-MAGNETIC-RESONANCE STUDIES

Homoleptic silver (I) complexes [Ag(L-L)(2)]BF4 {L-L = RE(CH2)(n)ER [R = Ph or Me, n = 2 or 3 (E = S or Se), n = 3 (E = Te)]} have been prepared and characterised by analysis, FAB mass spectrometry, and multinuclear NMR spectroscopy (H-1, Se-77, Te-125 and Ag-109). Variable-temperature NMR studies have been used to probe various exchange processes occurring in solution. The crystal structure of the tetrafluoroborate salt of [Ag(MeSeCH(2)CH(2)SeMe)(2)](+) shows the diselenoether ligands coordinated in a bidentate manner to the Ag-1 ion forming distorted tetrahedral 1+ cations. In contrast, in the crystal structure of the tetrafluoroborate salt of [Ag-n(PhSeCH(2)CH(2)CH(2)SePh)(2n)](n+) the cation is an infinite network comprising Ag atoms linked tetrahedrally via one of the Se atoms of four different diselenoether ligands, which are in turn linked to adjacent Ag atoms.