BINUCLEAR IRON(I), RUTHENIUM(I), AND OSMIUM(I) HEXACARBONYL COMPLEXESCONTAINING A BRIDGING BENZENE-1,2-DITHIOLATE LIGAND - SYNTHESIS, X-RAY STRUCTURES, PROTONATION REACTIONS, AND EHMO CALCULATIONS

The dithiolate-bridged complexes [M-2(mu-bdt)(CO)(6)] (M = Fe (1), Ru (2), Os (3); bdt = benzene-1,2-dithiolate) have been prepared. X-ray d iffraction studies have revealed that although the three compounds hav e analogous molecular structures their crystal structures are differen t as a result of different molecular packings. Complex 1 does not reac t with tetrafluoroboric acid in 1,2-dichloroethane, while compounds 2 and 3, under the same conditions, undergo protonation at the metal ato ms to give the cationic hydride derivatives [M-2(mu-H)(mu-bdt)(CO)(6)] [BF4] (M = Ru, Os). EHMO calculations have been used to rationalize th e results of the protonation reactions.