Crystal and molecular structure of a five-coordinate palladium(II) complex containing the bidentate azaheterocyclic ligand: Tris(dimethylphenylphosphine)-2,9- dimethyl-1,10-phenanthroline palladium(II) tetrafluoroborate

Abstract

The determination of the crystal and the molecular structure of a five-coordinate palladium(II) complex and its 1H and 31P NMR studies are described. The crystals of [Pd(PMe 2Ph) 3(2,9-Me 2-phen)][BF 4] 2 (C 38H 45,N 2P 3PdB 2F 8) are monoclinic, space group P2 1/ n, with Z = 4 and unit cell dimensions: a = 23.346(6), b = 13.429(2), c = 12.929(2) Å, β = 91.96(2)°. The structure was determined by a heavy-atom method from diffractometer data and refined to an R value of 0.048 for 4601 unique observed reflections. Three phosphorus atoms from the three dimethylphenylphosphines, and a nitrogen atom from the 2,9-dimethyl-1,10-phenanthroline (2,9-Me 2-phen), form an approximately square-planar configuration about the palladium atom; PdP(1) 2.283(1), PdP(2) 2.395(2), PdP(3) 2.407(2) and PdN(1) 2.164(5) Å. The remaining nitrogen atom is at the apex of a distorted square pyramid, PdN(10) 2.588(5) Å. The 1H NMR spectrum shows fluxional motion which averages the two halves of the 2,9-Me 2-phen.