Syntheses and structures of selenido dimanganese and iron–manganese carbonyl cluster complexes

The bis-selenido tetramanganese complex, Mn4(CO)15(PPh3)2(μ3-Se)2 (1), was obtained from the reaction of Mn2(CO)9(NCMe) with SePPh3. Three new bis-selenido bimetallic iron–manganese complexes, CpFeMn3(CO)13(PPh3)(μ3-Se)2 (2), Cp2Fe2Mn2(CO)10(PPh3)(μ3-Se)2 (3) and Cp2Fe2Mn2(CO)11(μ3-Se)2 (4) were obtained from the reaction of CpFeMn(CO)7 with SePPh3 in the presence of trimethylamine N-oxide. Compounds 1, 2 and 3 were characterized by single crystal X-ray diffraction analyses. All three complexes contain an M4(μ3-Se)2 cluster core with a carbonyl bridged MnMn single bond.