Alkyl and Alkylidyne Complexes of Rhenium

The multiplicity of its oxidation states enables the element rhenium to fix numerous ligand types in stable complexes. The synthesis of “Cp*ReClMe3” now completes the series of Rev complexes “Cp*ReClnMe4–n”. The neopentyl complex 1 reacts with C5H5TiCl3 to give the paramagnetic carbyne complex 2, which can be smoothly oxidized to the diamagnetic complex 3. Complexes 2 and 3 are the first π-cyclopentadienylcarbyne complexes with rhenium in high oxidation states (ReVI and ReVII, resp.). Cp* = η5-C5(CH3)5.