Ferrocene-vanadium complexes

Elements of the first transition series from vanadium to nickel form stable bis(7j-cyclopentadienyl) complexes having the normal ir-sandwich structure typical of ferrocene. In contrast, bis(Tj-cyclopentadienyl)ti-tanium, (i7-CsH5)2Ti (1), is not even known as a discrete compound. 

To our knowledge, the onyl vanadium-ferrocene complexes structurally characterized are Fe[ j5-C5H4-V(> 5-C5H4Me)2]2 [24] and [Fe( j -C5H4Se)2]V(0)(> -C5Me5) [25]. Their redox behavior is not known. 

The sandwich-type di-7i-cyclopentadienyl metal complexes of vanadium, chromium, cobalt, and nickel are isomorphous with monoclinic ferrocene. 

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