Reactions of organometallic compounds with metal halides

Reactions of organometallic compounds with metal halides 

By far the most versatile reagents in such syntheses are the organic derivatives of the most electropositive elements, especially, on account of their easy preparation, those of Li and Mg. These react rapidly and exothermically with halides of more electronegative elements. Examples are 

Cadmium alkyls are useful reagents in organic chemistry for the conversion of acyl halides to ketones. They are prepared in situ by the direct addition of anhydrous CdCl2 to an ether solution of the Grignard reagent. 

Organolithium compounds are more reactive than Grignard reagents, and in certain cases allow more complete substitution. For example, Grignard reagents substitute only two of the chlorine atoms in thallium (III) chloride when diethyl ether is the solvent, whereas lithium alkyls substitute all three  

Insertion of olefins and acetylenes into metal-hydrogen bonds 

These provide another general method for the preparation of organo-element 

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