Nickel catalysts have been known to be useful in cross-coupling these with aryl halides. Because of 
Nickel catalysts have been known to be useful in cross-coupling these with aryl halides. Because of their high reactivity, they do not store well and are normally synthesized fresh for each use; they can be used to make hydrocarbons, carboxcylic acids and other compounds in addition to their most common use. For ten points, name this chemistry staple which reacts with an aldehyde to form an alcohol and consists of an organic magnesium halide in a nonreactive solvent.
Nickel catalysts have been known to be useful in cross-coupling these with aryl halides.
{Grignard} reagent