Reactivity of Methylene-Bridged Transition Metal Complexes

REACTIVITY OF METHYLENE-BRIDGED TRANSITION METAL COMPLEXES 

Despite their thermodynamic stability, dimetallacyclopropanes proved to be quite reactive when treated with appropriate reagents, specifically, unsaturated hydrocarbons and protic acids. Again, the nature of the metals and coligands distinctly influence the reactivity. 

Intermolecular Carbene Exchange and Intramolecular Carbonyl Exchange 

Fischer et al. (212) and Stone et al. (93) encountered a very similar CO migration when they attempted the synthesis of a -phenylmethylidyne 

Treatment of 35 with ethylene (20 atm, benzene, 55°C) produces propylene ( 90%) and (C2H4)Fe(CO)4 in a reaction which, once again, is inhibited by CO. The same primary step as above, namely, addition of ethylene (instead of H2), is conceivable for this process, followed by 

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