Reformatsky Reaction

The reaction of α-halo ester with aldehydes or ketones in the presence of zinc metal to produce a β-hydroxy ester. This reaction is known as Reformatsky Reaction.

Mechanism of Reformatsky Reaction

Reformatsky reaction usually commences with the oxidative addition or insertion of the zinc into the carbon-halogen bond of α-haloester. After the insertion, the compounds coordinate with each other leading to the formation of a dimer. This compound further experiences a rearrangement which results in the emergence of two zinc enolates. Then, the oxygen of the ketone or aldehyde coordinates to the zinc and a new rearrangement is formed where the two reagents now have a carbon-carbon bond between them. Following that, an acid workup splits the zinc and oxygen bond to generate zinc(II) salt and β-hydroxy ester as the final products.