Substituent Effects on the Ring-Metal Bond

The first indication of an electronic effect in the ring migration studies was demonstrated when l,T-diethylferrocene was observed to undergo ligand exchange with mesitylene much more readily than did ferrocene 

Yield of Mesitylenecyclopentadienyliron Derivative from THE Reaction of Mesitylene and Substituted Ferrocene  

Results from these laboratories (79) likewise support the idea that the ring-metal bond of a ferrocene system is quite labile. Treatment of the optically active ketone (V) with refluxing nitromethane and AlClj brought recovery of the identical ketone 

Although l,T-diethylferrocene has been shown not to undergo synpro-portionation with ruthenocene, favorable results have now been obtained with RuClj (18). Ruthenocene and l,T-diethylruthenocene were isolated from the reaction of ferrocene and l,T-diethylferrocene, respectively, upon 

Ratio of Substituted Ring-Iron Cleavage to Unsubstituted Ring-Iron Cleavage for Para-Substituted Phenylferrocene  

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