Suzuki reaction

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The Suzuki reaction is the organic reaction of an aryl- or vinyl-boronic acid with an aryl- or vinyl-halide catalyzed by a palladium(0) complex.^[1][2] It is widely used to synthesize poly-olefins, styrenes, and substituted biphenyls. Several reviews have been published.^[3][4][5]

The reaction also works with pseudohalides, such as triflates (OTf), instead of halides, and also with boron-esters instead of boronic acids.

Relative reactivity: R₂-I > R₂-OTf > R₂-Br >> R₂-Cl

First published in 1979 by Akira Suzuki, the Suzuki reaction couples boronic acids (containing an organic part) to halides. The reaction relies on a palladium catalyst such as tetrakis(triphenylphosphine)palladium(0) to effect part of the transformation. The palladium catalyst (more strictly a pre-catalyst) is 4-coordinate, and usually involves phosphine supporting groups.

In many publications this reaction also goes by the name Miyaura-Suzuki reaction.

Contents 1 Reaction mechanism 1.1 Oxidative addition 1.2 Reductive elimination 2 References 3 External links 4 See also

[edit] Reaction mechanism

The mechanism of the Suzuki reaction is best viewed from the perspective of the palladium catalyst. The first step is the oxidative addition of palladium to the halide 2 to form the organo-palladium species 3. Reaction with base gives intermediate 4, which via transmetallation^[6] with the boron-ate complex 6 forms the organopalladium species 8. Reductive elimination of the desired product 9 restores the original palladium catalyst 1.

[edit] Oxidative addition

Oxidative addition proceeds with retention of stereochemistry with vinyl halides, while giving inversion of stereochemistry with allylic and benzylic halides.^[7] The oxidative addition initially forms the cis-palladium complex, which rapidly isomerizes to the trans-complex.^[8]

[edit] Reductive elimination

Using deuterium-labelling, Ridgeway et al. have shown the reductive elimination proceeds with retention of stereochemistry.^[9]

[edit] References

1. ^  Miyaura, N. et al. Tetrahedron Lett. 1979, 3437.
2. ^  Miyaura, N.; Suzuki, A. Chem. Commun. 1979, 866.
3. ^  Suzuki, A. Pure Appl. Chem. 1991, 63, 419-422. (Review)
4. ^  Miyaura, N.; Suzuki, A. Chem. Rev. 1995, 95, 2457-2483. (Review, DOI:10.1021/cr00039a007)
5. ^  Suzuki, A. J. Organometallic Chem. 1999, 576, 147–168. (Review)
6. ^  Matos, K.; Soderquist, J. A. J. Org. Chem. 1998, 63, 461–470. (DOI:10.1021/jo971681s)
7. ^  Stille, J. K.; Lau, K. S. Y. Acc. Chem. Res. 1977, 10, 434–442. (DOI:10.1021/ar50120a002)
8. ^  Casado, A. L.; Espinet, P. Organometallics 1998, 17, 954–959.
9. ^  Ridgway, B. H.; Woerpel, K. A. J. Org. Chem. 1998, 63, 458–460. (DOI:10.1021/jo970803d)

[edit] External links

• Suzuki coupling

[edit] See also

• Heck reaction
• Hiyama coupling
• Kumada coupling
• Negishi coupling
• Petasis reaction
• Stille reaction