Carbonyl complexes, reaction with organomagnesium compound

The complexities of their constitution in solution make studies of the mechanism of reactions of organomagnesium compounds extraordinarily difficult. Few reactions have stimulated such a wealth of elegantly planned and meticulously executed experiments as those of Grignard reagents with carbonyl compounds (see Section 6.1). Fortunately an admittedly grossly oversimplified rationale for the reactivity of organomagnesium compounds, and in particular for the influence of solvation, is adequate for most applications in organic synthesis. In a monomeric, unsolvated species (2),... 

Similarly, reactions of organomagnesium compounds with metal carbonyls have not been found useful for synthesizing carbene complexes. On the other hand, reactions of organomagnesium compounds with iron... 

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