Syntheses of the 47 Electron Clusters [(CpFe)3(μ3-X)2] (X = S, Se) and the First Fe/Sn/Se Heterocubane Cluster [(CpFe)3(SnCl3)(μ3-Se)4]·DME by the Use of Chalcogenostannate Salts

By reacting 1-aminoethylammonium (H2NCH2CH2NH3 + = enH+) salts of [Sn2E6]4- anions (E = S, Se), [enH]4[Sn2S6] (1) and [enH]4[Sn2Se6]·en (2), with FeCl2/LiCp*, three novel (partly) oxidized, Cp* ligated iron chalcogenide clusters were synthesized. Two of them, [(Cp*Fe)3(μ3-S)2] (3) and [(Cp*Fe)3(μ3-Se)2] (4), contain formally 47 valence electrons. [(Cp*Fe)3(SnCl3)(μ3-Se)4]·DME (5) represents the first known mixed metal Fe/Sn/Se heterocubane type cluster. Compounds 3−5 were structurally characterized by single-crystal X-ray diffraction, and the odd valence electron number of the [Fe3E2] clusters (E = S, Se) was confirmed by density functional (DFT) investigations, mass spectrometry, cyclic voltammetry and a susceptibility measurement of 3.