The formation of ester-stabilized organozinc reagents and their addition to carbonyl compounds
Mechanism of the Reformatsky Reaction
Organozinc compounds are prepared from α-halogenesters in the same manner as Grignard Reagents. This reaction is possible due to the stability of esters against organozincs. Due to the very low basicity of zinc enolates, there is hardly any competition from proton transfer, and the scope of carbonyl addition partners is quite broad. In presence of ketones or aldehydes, the organozinc compounds react as the nucleophilic partner in an addition to give β-hydroxy esters.
An ester-stabilized organozinc reagent
Compared to organolithiums and organomagnesium halides (Grignard reagents), the organozinc halide reagents used in the Reformatsky Reaction are relatively stable, and many are available commercially.
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