New iron-sulphur clusters containing thiocarboxamide, amino-carbyne and amino-carbene ligands

Heating Fe3(CO)12 with 1,3,5-Me3C6(CH2S2CNEt2)3 (1) in boiling toluene affords [Fe3(CO)9(μ3-S)2] (2), together with small amounts of the new clusters [Fe4(CO)12(μ-η1,κ1-SCNEt2)(μ-η1-CNEt2)(μ4-S)] (3) and [Fe3(CO)8(η1-CHNEt2)(μ3-S)2] (4), all three resulting from C-S bond scission. Looking for a more rational route to amino-carbene clusters like 4 we have found that heating Fe3(CO)12 and thioacetamide in CH2Cl2 affords [Fe3(CO)8(η1-CMeNH2)(µ3-S)2] (5). Molecular structures of 3–5 have been determined by single-crystal X-ray diffraction analyses. Cluster 3 contains an edge-bridging amino-carbyne ligand, while 4–5 accommodate Fischer-type amino-carbene ligands.