organozink

Organozinc refers to a class of organometallic compounds containing a carbon-zinc covalent bond. These compounds are characterized by the general formula RZnX, where R is an organic group and X is a halogen, or R2Zn, where both R groups are organic. Organozinc compounds are versatile reagents in organic synthesis, primarily used for the formation of carbon-carbon bonds.

One of the most well-known reactions involving organozinc reagents is the Reformatsky reaction. In this reaction, an alpha-halo ester is treated with zinc metal to form an organozinc enolate, which then reacts with a carbonyl compound (aldehyde or ketone) to produce a beta-hydroxy ester. Another important application is in Negishi coupling, a palladium-catalyzed cross-coupling reaction between an organozinc halide and an organohalide. This reaction is highly effective for forming carbon-carbon bonds between sp2 or sp3 hybridized carbons.

Organozinc compounds are generally less reactive and more tolerant of functional groups compared to Grignard reagents or organolithium compounds. This makes them suitable for reactions where other organometallic reagents might interfere with sensitive functional groups. They are typically prepared by the reaction of an organic halide with zinc metal, often activated or in the presence of additives. Their stability and reactivity profile make them valuable tools in complex molecule synthesis, including pharmaceuticals and natural products.