Tuning structure and properties of Pd and Pt camphor derived complexes

Seven new camphor palladium or platinum compounds with novel metal coordination environments were obtained by convenient choice of the experimental conditions in particular the solvent. cis-[PtCl2(PhNC10H14O)2]) and [Pd(MeNNC10H14O)2] were structurally characterized by X-ray diffraction analysis while [{PtCl2(Me2NC10H13NSO2)}2], [{PdCl2(YNC10H14O)}2] (Y = NMe2, NPh2) and [Pd(PhNNC10H14O)2] were formulated by elemental analysis and spectroscopic techniques. Relevant aspects of the IR and NMR spectra of complexes [Pd(YNC10H14O)2] (Y = MeN, PhN) are discussed with the help of DFT calculations.Evaluation of the properties of the new complexes as catalysts for activation of 4-pentyn-1-ol towards formation of cyclization products showed that [{PdCl2(Ph2NNC10H14O)}2] is more efficient than [PdCl2(Me2NNC10H14O)2] which is one of the more efficient camphor derived catalysts reported before. In contrast the chelate complexes [Pd(YNC10H14O)2] (Y = MeN, PhN) display no catalytic activity.

Seven new camphor derived Pd(II) and Pt(II) complexes with different geometries (cis or trans), ligand to metal ratios (2:1 or 1:1) and coordination modes (monodentate, chelate) are obtained by tuning the experimental conditions and/or substituents in the camphorimine ligand.Figure optionsDownload as PowerPoint slideHighlights
► Palladium and platinum complexes with camphorimine ligands.
► New types of geometry and metal to ligand ratios.
► Structural characterization of the new complexes by X-ray analysis.
► Rationalization of spectroscopic properties by DFT calculations.
► Effects of the characteristics of the complexes in their catalytic activity on cyclization of 4-pentyn-1-ol.