A beta-ketoiminato palladium(II) complex for palladium deposition

摘要

The beta-ketoiminato complex [Pd(OAc)L] (3) can be synthesized by the reaction of bis(benzoylacetone)diethylenetriamine (1, =LH) with [Pd(OAc)(2)] (2). The structure of 3 in the solid state has been determined by single X-ray diffraction analysis. Complex 3 crystallizes as a dimer (3(2)), which is formed by hydrogen bonds between NH and O-OAC functionalities of two adjacent ligands. Each of the Pd atoms is complexed by one ON2 donor unit of the polydentate ligand L- and an acetate group. Pd-Pd interactions and hydrogen bond formation between a NH and the C=O acetate moiety lead to a [4 +2] coordination at Pd. The non-coordinated part of L exists in its beta-keto-enamine form. The thermal decomposition behavior of 3(2) was studied by TG (thermogravimetry) and TG-MS showing that 3(2) decomposes between 200 and 500 degrees C independent of the applied atmosphere. Under oxygen PdO is produced, while under argon Pd is formed as confirmed by PXRD measurements. Complex 3(2) was applied as a spin-coating precursor (conc. 0.1 mol L-1, volume 15 mL, 3000 rpm, deposition time 6 min, heating rate 50 K min(-1), holding time 60 min (Ar) and 120 min (air) at T= 800 degrees C). The as-obtained samples are characterized by granulated particles of Pd/PdO on the substrate surface. EDX (energy-dispersive X-ray spectroscopy) and XPS (X-ray photoelectron spectroscopy) measurements confirmed the formation of Pd (Ar) or PdO (O-2) with up to 12 mol% C impurity.