The Synthesis, Structure and Thermal Rearrangement Reaction of Tetramethyldisilane-bridged Bis(1-phenylcyclohexylcyclopentadienyl)tetracarbonyl Diiron

The reaction of 1,2-bis(1-phenylcyclohexylcyclopentadineyl)tetramethyldisilane with Fe(CO)_(5) in refluxing xylene afforded the diiron complex(Me_(2)SiSiMe_(2))[(1-Ph-c-C_(6)H_(10)C_(5)H_(3))Fe·(CO)]_(2)(#mu#-CO)_(2)(2), existing as a mixture of cis and trans isomers(2c and 2t), which were separated by column chromatography. When the two isomers were heated in refluxing xylene, the cis substrate(2c) rearranged to the trans product[Me_(2)Si(1-Ph-c-C_(6)H_(10)C_(5)H_(3))Fe(CO)_(2)]_(2)(3t), while the trans substrate(2t) yielded the cis product(3c), respectively. This indicates that the rearrangement reaction is stereospecific. The molecular structures of compound 3c and 4t were determined by X-ray diffraction analysis.