Addition to carbon monoxide and metal carbonyls

Grignard, Compt. Rend. C. R. Hebd, Seances Acad. Sci. 138,152 (1904). 

Fujisawa, T. Mori, K. Higuchi and T. Sato, Chem. Lett., 1791 (1983). 

Organomagnesium compounds are less reactive than organolithium compounds [E] towards carbon monoxide and metal carbonyls. The initial reaction with carbon monoxide is similar — addition to give an acylmagnesium compound  

However, many subsequent reactions can occur, and the outcome is not generally useful for synthesis [1, 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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