• The reaction is the
catalyzed by a
is widely used to
, and substituted
, and has been extended to incorporate alkyl bromides.
Several reviews have been published .
Scheme 1. The Suzuki coupling of aryl chlorides
The cross-coupling reactions of organoboron compounds with organic halides or
related electrophiles provide one of the most straightforward methodologies for
various carbon–carbon bond formations. The characteristics of organoboron
reagents (i.e., high selectivity in cross-coupling reactions, stability, nontoxic nature,
and tolerance towards functional groups) often gives the Suzuki coupling a practical
advantage over other cross-coupling processes.
It has now confirmed that all kinds of carbon–boron bonds including (sp3)C–B,
(sp2)C–B, and (sp)C–B bonds are employed as cross-coupling partners in the
Among such organoboron compounds, alkynylborane derivatives were not used in
the Suzuki coupling, because they are stronger Lewis acids and easily hydrolyzed in
the presence of bases.
The reaction also works with
, such as
(OTf), instead of
, and also with boron-esters instead of boronic acids.
Relative reactivity: R-I > R-OTf > R-Br >> R-Cl
Aryl halides (bromides or iodides) and triflates substituted with electron-
withdrawing groups (EWGs) are suitable substrates for the cross-coupling reaction.
Only aryl bromides and iodides can be used, as the chlorides only react slowly.
Byproducts such as self-coupling products, coupling products of phosphine-bound
aryls, are often formed.
, more formally known as
, is a
with the formula CF3SO3-. The
triflate anion, CF3SO3- is an extremely stable
, being the
of the strongest
known. It is defined as a
, because it is more acidic than pure