NCN palladium pincer via transmercuration. Synthesis of [2-(2-oxazoliny)-6-(2-pyridyl)] phenylpalladium(II) chloride and its catalytic activity in Suzuki coupling

•An unsymmetrical NCN palladium pincer via organomercurial was synthesized.•Their UV–vis, single crystal structures were studied.•This pincer is highly active to Suzuki coupling.

The unsymmetrical NCN ligand 1-(2-oxazolinyl)-3-(2-pyridyl)benzene 6 was synthesized starting from m-bromotoluene after a series of transformations. The reaction of 6 and mercury (II) acetate resulted in mercurial derivative 7 which was transformed into the corresponding NCN palladium pincer 8via transmercuration. The ultraviolet spectra of 6–8 in acetonitrile were also studied. The structures of 6 and 8 were further confirmed by X-ray single crystal diffraction. The carbon–carbon cross coupling reactions between aryl halides and phenylboronic acid catalyzed by 8 were investigated. The results indicate that this palladium pincer is more highly active to the coupling of aryl bromides than aryl chlorides.

Graphical abstractNCN ligand 6 is synthesized by a series of transformations starting from 1. Mercuration of 6 and followed by transmetalation affords the palladium pincer 8. This pincer is more highly active to Suzuki coupling.Figure optionsDownload full-size imageDownload as PowerPoint slide