Hydrogen bond networks in five- and eight-membered palladium and platinum complexes derived from bis(2-aminophenyl)ether and bis(2-aminophenyl)thioether ligands

Abstract

The reaction of [MII(MeCN)2Cl2] (M=Pd, Pt) with the diamino ligands either bis(2-aminophenyl)ether or bis(2-aminophenyl)thioether {(NH2-C6H4)2D} [D=O (L1); D=S (L2)] yielded neutral coordination complexes of general formulae [M(Ln)Cl2] [M=Pd, n=1 (1); Pt, n=1 (2); Pd, n=2 (3); Pd, n=2 (4); Pt, n=2 (5). The reaction of L2 with K2[PtCl6] promoted the mono-deprotonation of the diamino ligand to yield the neutral complex [PtIV{(NH2-C6H4)S(NH-C6H4)}Cl3] (6); when the H2[PtCl6] acid was used an ionic complex [PtIV(L2)Cl3]Cl (7) was obtained. All complexes were characterized by NMR in solution, vibrational spectroscopy, and by X-ray diffraction studies. The molecular structures of the complexes revealed different coordination patterns of the diamino ligands; L1 just displayed a κ2N mode meanwhile L2 exhibited a wide variety of patterns (κ2N, κNκS, and κ2NκS) forming chelate rings of five- or eight-members. The presence of N–H functions in the ligand moieties enhanced the formation of extended hydrogen-bond networks; these supramolecular arrangements were mainly discussed at unitary and binary levels and sorted according to the molecular coordination patterns observed.