Palladium [PdCl2(L)] complexes with N-alkylpyridylpyrazole derived ligands [2-(5-trifluoromethyl-1H-pyrazol-3-yl)pyridine (L1), 2-(1-ethyl-5-trifluoromethyl-1H-pyrazol-3-yl)pyridine (L2), 2-(1-octyl-5-trifluoromethyl-1H-pyrazol-3-yl)pyridine (L3), and 2-(3-pyridin-2-yl-5-trifluoromethyl-pyrazol-1-yl)ethanol (L4) were synthesised. The crystal and molecular structures of [PdCl2(L)] (L = L2, L3, L4) were resolved by X-ray diffraction, and consist of monomeric cis-[PdCl2(L)] molecules. The palladium centre has a typical square-planar geometry, with a slight tetrahedral distortion. The tetra-coordinate metal atom is bonded to one pyridinic nitrogen, one pyrazolic nitrogen and two chlorine ligands in cis disposition. Reaction of L (L2, L4) with [Pd(CH3CN)4](BF4)2, in the ratio 1M:2L, gave complexes [Pd(L)]2(BF4)2. Treatment of [PdCl2(L)] (L = L2, L4) with NaBF4 and pyridine (py) and treatment of the same complexes with AgBF4 and triphenylphosphine (PPh3) yielded [Pd(L)(py)2](BF4)2 and [Pd(L)(PPh3)2](BF4)2 complexes, respectively. Finally, reaction of [PdCl2(L4)] with 1 equiv of AgBF4 yields [PdCl(L4)](BF4). © 2006 Elsevier B.V. All rights reserved.
- 1,3,5-Pyrazole derived ligands
- Crystal structure
- Palladium complexes