Suzuki Coupling

The scheme above shows the first published Suzuki Coupling, which is the palladium-catalysed cross coupling between organoboronic acid and halides. Recent catalyst and methods developments have broadened the possible applications enormously, so that the scope of the reaction partners is not restricted to aryls, but includes alkyls, alkenyls and alkynyls. Potassium trifluoroborates and organoboranes or boronate esters may be used in place of boronic acids. Some pseudohalides (for example triflates) may also be used as coupling partners.

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Mechanism

One difference between the Suzuki mechanism and that of the Stille Coupling is that the boronic acid must be activated, for example with base. This activation of the boron atom enhances the polarisation of the organic ligand, and facilitates transmetallation. If starting materials are substituted with base labile groups (for example esters), powdered KF effects this activation while leaving base labile groups unaffected.

In part due to the stability, ease of preparation and low toxicity of the boronic acid compounds, there is currently widespread interest in applications of the Suzuki Coupling, with new developments and refinements being reported constantly.

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Recent Literature

Boronic Acids: New Coupling Partners in Room-Temperature Suzuki Reactions of Alkyl Bromides. Crystallographic Characterization of an Oxidative-Addition Adduct Generated under Remarkably Mild Conditions
J. H. Kirchhoff, M. R. Netherton, I. D. Hill, G. C. Fu, J. Am. Chem. Soc., 2002, 124, 13662-13663.

Pd(N,N-Dimethyl β-alaninate)₂ as a High-Turnover-Number, Phosphine-Free Catalyst for the Suzuki Reaction
X. Cui, T. Qin, J.-R. Wang, L. Liu, Q.-X. Guo, Synthesis, 2007, 393-399.

Guanidine/Pd(OAc)2-Catalyzed Room Temperature Suzuki Cross-Coupling Reaction in Aqueous Media under Aerobic Conditions
S. Li, Y. Lin, J. Cao, S. Zhang, J. Org. Chem., 2007, 72, 4067-4072.

An N-Heterocyclic Carbene Ligand with Flexible Steric Bulk Allows Suzuki Cross-Coupling of Sterically Hindered Aryl Chlorides at Room Temperature
G. Altenhoff, R. Goddard, C. W. Lehmann, F. Glorius, Angew. Chem. Int. Ed., 2003, 42, 3690-3693.

Reusable and Efficient Pd(OAc)₂/TBAB/PEG-400 System for Suzuki-Miyaura Cross-Coupling Reaction under Ligand-Free Conditions
W.-J. Liu, Y.-X. Xie, Y. Liang, J.-H. Li, Synthesis, 2006, 860-864.

Synthesis and Characterization of R2PN=P(ⁱBuNCH₂CH₂)₃N: A New Bulky Electron-Rich Phosphine for Efficient Pd-Assisted Suzuki-Miyaura Cross-Coupling Reactions
J. V. Kingston, J. G. Verkade, J. Org. Chem., 2007, 72, 2816-2822.

Modified (NHC)Pd(allyl)Cl (NHC = N-Heterocyclic Carbene) Complexes for Room-Temperature Suzuki-Miyaura and Buchwald-Hartwig Reactions
N. Marion, O. Navarro, J. Mei, E. D. Stevens, N. M. Scott, S. P. Nolan, J. Am. Chem. Soc., 2006, 128, 4101-4111.

A Highly Active Catalyst for Suzuki-Miyaura Cross-Coupling Reactions of Heteroaryl Compounds
K. L. Billingsley, K. W. Anderson, S. L. Buchwald, Angew. Chem. Int. Ed., 2006, 45, 3484-3488.

Palladium catalyzed Suzuki-Miyaura coupling with aryl chlorides using a bulky phenanthryl N-heterocyclic carbene ligand
C. Song, Y. Ma, Q. Chai, C. Ma, W. Jiang, M. B. Andrus, Tetrahedron, 2005, 61, 7438-7446.

New Catalysts for Suzuki-Miyaura Coupling Reactions of Heteroatom-Substituted Heteroaryl Chlorides
A. S. Guram, X. Wang, E. E. Bunel, M. M. Faul, R. D. Larsen, M. J. Martinelli, J. Org. Chem., 2007, 72, 5104-5112.

Stereoselective Enol Tosylation: Preparation of Trisubstituted α,β-Unsaturated Esters
J. Baxter, D. Steinhuebel, M. Palucki, I. W. Davies, Org. Lett., 2005, 7, 215-218.

N-Vinylpyridinium and -ammonium Tetrafluoroborate Salts: New Electrophilic Coupling Partners for Pd(0)-Catalyzed Suzuki Cross-Coupling Reactions
K. R. Buszek, N. Brown, Org. Lett., 2007, 9, 707-710.

The First General Palladium Catalyst for the Suzuki-Miyaura and Carbonyl Enolate Coupling of Aryl Arenesulfonates
H. N. Nguyen, X. Huang, S. L. Buchwald, J. Am. Chem. Soc., 2003, 125, 11818-11819.

The use of bisphosphine ligands with a large P-Pd-P bite angle allowed to synthesize Z-chlorinated internal alkenes in good yields by a selective Suzuki-Miyaura monocoupling process of 9-alkyl-9-BBN with 1,1-dichloro-1-alkenes. These monochlorinated olefins could be further transformed providing stereospecifically trisubstituted olefins.
F. Liron, C. Fosse, A. Pernolet, E. Roulland, J. Org. Chem., 2007, 72, 2220-2223.

Stereoselective Cross-Coupling Reaction of 1,1-Diboryl-1-alkenes with Electrophiles: A Highly Stereocontrolled Approach to 1,1,2-Triaryl-1-alkenes
M. Shimizu, C. Nakamaki, K. Shimono, M. Schelper, T. Kurahashi, T. Hiyama, J. Am. Chem. Soc., 2005, 127, 12506-12507.

Suzuki-Miyaura Cross-Coupling Reactions of Potassium Alkenyltrifluoroborates
G. A. Molander, C. R. Bernardi, J. Org. Chem., 2002, 67, 8424-8429.