Cyclopentadienyl complexes of uranium, thorium and actinide metals

Like the ionic alkali metal cyclopentadienides, manganocene hydrolyses easily, giving cyclopentadiene and the metal hydroxide and reacts with CO2 giving carboxylic acid salts. 

Although the remaining sandwich complexes of the first row of the transition metals are considered to be covalent there is always some charge 

The bonding in mono-n-cyclopentadienyl transition metal complexes 

Such considerations indicate that the conventional ideas of transition metal stereochemistry and co-ordination number should be applied with great caution to organometallic complexes. 

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