On the basis of our observations and the known palladium
chemistry, a possible mechanism for the palladium-catalyzed
acylative Suzuki coupling reaction is proposed (Scheme 2):
Oxidative addition of the triazine ester to the Pd(0)-species to
generate an acylpalladium(II) complex II; transmetalation
between acylpalladium(II) and the arylboronic acid to create
the complex III; and, finally, reductive elimination to form the
new C−C bond and regeneration of Pd(0)-species.
In conclusion, a one-pot reaction was developed for the
synthesis of asymmetric aryl ketones using aromatic triazine
esters as electrophiles. The procedure employs low catalyst
loadings and has demonstrated tolerance to a variety of
functional groups. Compared with the previous transitionmetal-
catalyzed protocols, this facile palladium-catalyzed Suzuki
cross-coupling reaction has greater efficiency due to the two
reactions sequence being carried out in a one-pot procedure.
This is particularly important in large-scale synthesis of
asymmetric aryl ketones.