Synthesis, spectroscopic characterization and catalytic activity of platinum(II) carbene complexes

• Synthesis of an NHC-platinum(II) complex.
• Characterization of the complex using XRD and XAS techniques.
• Determination of the local binding environment around platinum using XANES data.
• Catalytically active in hydrosilylation.

A novel platinum complex with 1,3-bis(2,6-diisopropylphenyl)-1,3-dihydro-2H-imidazol-2-ylidenyl ligand has been synthesized and characterized on the basis of elemental analysis, MS, 1H and 13C NMR spectroscopy, X-ray Absorption Spectroscopy and single crystal X-ray diffraction studies. The XRD determination of the complex (monoclinic, C2/c) revealed a structure in which the platinum (II) centre coordinates two chlorides, a carbon atom of the N-heterocyclic carbene (NHC) and is stabilized by coordinating the nitrogen atom of a 3-chloropyridine molecule, forming an over-all square planar geometry. By prolonging the time of the reaction, it was possible to obtain the trans-dichloridobis(3-chloropyridine) platinum(II) complex under the same reaction conditions. The electronic and molecular properties of both complexes were investigated and compared by means of Near Edge X-ray Absorption Fine Structure spectroscopy (NEXAFS), supported by numerical simulations. The platinum carbene complex obtained was tested in a series of C–H activation and hydrosilylation reactions.

An NHC platinum complex is characterized by inter alia XANES and is catalytically active in hydrosilylation.Figure optionsDownload as PowerPoint slide