Photolytically induced reactions of CpCo(CO)2 (Cp = C 5H5, C5H4Me, C5Me 5 and C5Ph5) with thiirane yielding dinuclear 1,2-ethanedithiolato-S,S complexes

The complexes CpCo(CO)2 (Cp = C5H5, C 5H4Me, C5Me5 and C 5Ph5) (1a-d) react with thiirane C2H 4S under UV-irridiation in THF to form the dinuclear μ2-1,2-ethanedithiolate-S,S complexes [(CpCo)2(μ 2-S2C2H4)] (2a-d) as main products. Using column chromatography, in case of Cp = C5H5Me also the dimeric complex [C5H4MeCo(μ2-S 2C2H4)]2 (3b), in case of Cp = C5Ph5 the mixed disulfido-sulfido complex [(C 5Ph5Co)2(μ2-S2) (μ2-S)] (4d) were isolated in small yields. Only 2a reversibly adds SO2 gas to form the μ2-SO2 complex [(C5H5CoSCH2)2(μ2- SO2)] (5a). A bromo ligand bridging the Co atoms can be introduced by the reaction of [(C5Me5Co5Br 2)]2 (6c) with 1,2-ethanedithiol which gives the cationic complex [(C5Me5CoSCH2) 2(μ2-Br)]2CoBr4 (7c). All compounds have been characterized by their IR, 1H and 13C NMR and MS spectra and compounds 2b-d, 3b and 7c by X-ray structure analyses, which prove the pseudo tetrahedral skeleton (CpCoS)2 and the ethane bridge between both sulfur atoms. 3b shows, however, a new unsymmetrical bonding mode of both dithiolato bridges with η1-S und μ2-S ligand functions. © 2006 Verlag der Zeitschrift für Naturforschung.