What is Suzuki Coupling?

03/21/2018

Suzuki coupling is a widely used cross coupling reaction between an organohalide and typically an orgaonoborinic acid. The reaction is typically catalysed by a Pd-based catalyst and runs under mild conditions. A wide variety of solvents can be used, including water, aromatic solvents such as toluene and ethers such as THF. This reaction has found use in both the agrochem and pharmaceutical areas due to its broad capability.

Suzuki coupling is named for Akira Suzuki, a co-recipient (along with Heck and Negishi) of the 2010 Nobel Prize in chemistry for his contributions to the science of Palladium-catalysed cross coupling reactions in organic synthesis.

Reaction Mechanism

The reaction mechanism has been well studied and can be described as follows:

  1. The oxidative addition of the organohalide to the catalytically active Pd0 species, which forms an organopalladium (II) complex.
  2. A transmetalation reaction between the previously formed organopalladium (II) complex and the organoborinic acid forms a diorganopalladiun (II) complex.
  3. The diorganopalladium (II) undergoes a reductive elimination reaction, forming the desired product and regenerating the catalytically active Pd0‑complex.

The one ambiguous aspect of the reaction mechanism is the original formation of the catalytically active Pd0 complex. The Pd is added to the reaction mixture as a Pd2+salt and yet the reaction starts as soon as the reagents are co-titrated into the reactor suggesting that the Pd0 species is present. There have been several theories proposed to explain this chemistry but conclusive proof has not been presented.

Benefits

The Suzuki coupling reaction has been well-accepted because the more common organoboronic and borinic acids are commercially available or are relatively inexpensive to produce. In general the toxicity of the organoboron compounds are lower than other organometallics that might be considered for this chemistry.

Applications

Suzuki coupling can be the reaction of choice for the production of intermediates and finished products for agrochems, pharmaceuticals and other fine and specialty chemicals. JAYHAWK uses Suzuki coupling in the production of our chemical building blocks. Our team is eager to help you with our manufacturing solutions. If you would like any more information about our capabilities and the chemistries we use, including Suzuki coupling, please contact us.