Reactions of (μ-η2-RCHCH)(μ-Cl)Fe2(CO)6 with [(μ-E)(μ-R1E1)Fe2(CO)6]− (E, E1=S or Se). Synthesis and characterization of (μ-η2-RCHCH)(μ-R1S)[Fe2(CO)6]2(μ4-E) and [(μ-η2-PhCHCH)Fe2(CO)6]2(μ4-Se)

A new synthetic route to μ4-S clusters (μ-η2-RCHCH)(μ-R1S)[Fe2(CO)6]2(μ4-S) has been discovered, which involves the reaction of (μ-η2-RCHCH)(μ-Cl)Fe2(CO)6 (1) with [(μ-S)(μ-R1S)Fe2(CO)6]−. A similar reaction between 1 and [(μ-Se)(μ-R1S)Fe2(CO)6]− gives μ4-Se complexes (μ-η2-RCHCH)(μ-R1S)[Fe2(CO)6]2(μ4-Se), while the reaction of 1 (R=Ph) with [(μ-Se)(μ-PhSe)Fe2(CO)6]− yields [(μ-η2-PhCHCH)Fe2(CO)6]2(μ4-Se). The crystal structure of complex (μ-η2-PhCHCH)(μ-EtS)[Fe2(CO)6]2(μ4-S) was determined by single-crystal X-ray diffraction.