Question

How do you make grignard reagent mechanisms?

Answer 1

For the formation of Grignards, or for their action?

Explanation:

As far as anybody knows, Grignards form via radical mechanisms on a metallic surface to give `R-MgX`, or `R^(delta-)""^(delta+)MgX`, where the ipso carbon, the carbon directly bound to the metal, is a formal carbanion.

Usually, the Grignard is poured directly onto dry ice to give a carboxylate salt that is one carbon longer than the original hydrocarbyl residue.

`R^(delta-)""^(delta+)MgX+CO_2(s)rarrRCO_2^(-)""^(+)MgX`

And aqueous work up gives the carboxylic acid as required, i.e. `RCO_2H`.