Mechanistic insights into the transmetalation step of a Suzuki-Miyaura reaction of 2(4)-bromopyridines: Characterization of an intermediate
C. Sicre, A. A. C. Braga, F. Maseras, M. M. Cid
Tetrahedron 2008, 64, 7437-7443
Abstract: The mechanistic study of the palladium-catalyzed Suzuki–Miyaura cross-coupling between bromophenylpyridine compounds and phenylboronic acid led to the NMR identification of a transient intermediate in the transmetalation step. This species was identified by DFT calculations as a [Pd{Ph-B(OH)3-}{C5H2RN}(PR3)2] complex, containing a boronate ligand coordinated through an oxygen group to the metal center. The fitting of this intermediate within recent mechanistic proposals on the mechanism of transmetalation is discussed.