chapter 2 palladium catalysts in suzuki cross- coupling reaction

2.2. The Suzuki Reactions
The coupling reactions of organoboron compounds with aryl, alkenyl, and
alkynyl halides, which is referred to as Suzuki or Suzuki-Miyaura reaction, was first
applied by Suzuki and Miyaura. In their study, cross-coupling reactions of 1-
alkenylboronic esters and 1-bromo or 1-iodo-1-alkenes were performed. Later on, the
methodology has found wide acceptance for the synthesis of biaryl reagents.
Ar-X + Ar'-B(OH) 2
X = Halogen, OTf
Pd, Base
Ar-Ar'
Figure 2.3. General representation of Suzuki reaction
The Suzuki coupling reactions have many advantages (Suzuki 2005, Suzuki 1999,
Kotha et al. 2002). These are;
• The reactants are readily available, nontoxic, and air-stable.
• Reactions are largely unaffected by the presence of water.
• Reactions can be performed under mild conditions and are amenable to a variety
of reaction conditions, including the use of aqueous solvents and substrate
supports.
• The boron-containing byproduct is environmentally safe and can be easily
removed after the reaction when compared to byproducts of other
organometallic reagents.
• Most important of all, the coupling reaction proceeds with high regio- and stereo
selectivity, and is little affected by steric hindrance. It does not affect other
functional groups in the molecule.
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