The Negishi Coupling is the nickel or palladiumcatalyzed stereoselective reaction of organozincs and organic halides.

Reaction mechanism:
1. Initially, the electronrich Pd(0) catalyst inserts into the R–X bond of the organic halide. This oxidative addition forms an organoPd(II)complex.
2. Subsequent transmetalation with the organozinc reagent forms a heteroorganometallic complex.
3. Before the next step, isomerization is necessary to bring the organic ligands next to each other into cis positions.
4. Finally, reductive elimination leads to the formation of a C–C bond and releases the crosscoupled product while regenerating the Pd(0) catalyst.

Pinterest:
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References:
NROChemistry: https://nrochemistry.com/negishicoup...
Example #1. Yifan Deng, ChiaPing H. Yang, and Amos B. Smith III, J. Am. Chem. Soc. 2021, 143, 4, 1740–1744. https://pubs.acs.org/doi/pdf/10.1021/...
Example #2. D. Ma, Y. Liu, Z. Wang, Angew. Chem. Int. Ed. 2017, 56, 7886. https://onlinelibrary.wiley.com/doi/1...