Hydrogen-bond mediation of supramolecular aggregation in neutral bis-(C₆F₅)Pt complexes with aromatic H-bond donating ligands. A synthetic and structural study

Abstract

Six pentafluorophenylplatinum(II) complexes containing proton acceptor atoms (F) and pyridine-like aromatic ligands able to act as proton donors have been synthesized and characterized, with emphasis on the factors that mediate their supramolecular aggregation in the solid state--hydrogen bonds and pi-pi interactions. The crystal structure analyses of the mononuclear complexes cis-[Pt(C6F5)2(napy)](1), cis-[Pt(C6F5)2(CH2napy)](3), cis-[Pt(C6F5)2(2-ammpy)](5), and cis-[Pt(C6F5)2(2-bipym)](6) reveal the influence of D-HPt and D-HF (D=C, N) hydrogen bonding on the organization of molecules into stacks, which can be further interconnected to generate channels. The prevalence of hydrogen bonding over pi-pi interactions between aromatic rings in establishing the nature of the observed supramolecular aggregation is demonstrated.

A Dinuclear Phosphidoplatinum(II) Fragment as a Building Block for Tri‐, Tetra‐, Hexa‐, and Octanuclear Complexes

“…[29][30][31][32] (5), [33] which were identified by IR spectroscopy. The two complexes can be easily separated from this solid by dissolving 5 in acetone.…”

Third‐Generation Scorpionates [RBpz3]– – How Influential Is the Nondonor Substituent R?

“…In this context, the substituent R = C 6 F 5 was chosen for the following reasons: (1) The group electronegativity of the pentafluorophenyl fragment is among the highest of all comparable organic moieties and, thus, should have some impact on the ligand properties of the tris(pyrazol‐1‐yl)borate anion. (2) Fluoroaromatics have a propensity to engage in C–F ··· H–C hydrogen bridges as well as aryl ··· perfluoroaryl bonding interactions . Therefore, we expect the C 6 F 5 substituent to provide a useful influence on the supramolecular organisation of [(C 6 F 5 Bpz 3 )ML n ] complexes in the crystal lattice.…”

Bis{μ-2-[(2-carbamoylhydrazin-1-ylidene)methyl]phenolato}bis[chloridozinc(II)] methanol disolvate, with non-aromatic–aromatic π–π stacking and N—H...Cl—Zn hydrogen bonding

“…Dance & Scudder (1995) suggested the concept of 'molecular embrace', based on phenyl-phenyl intermolecular interactions, and developed the embrace paradigm as an important and widespread intermolecular motif and crystal engineering tool by analysing the packing of molecules in crystals (Dance & Scudder, 2009). Varied hydrogen-bond patterns, including traditional and nonclassical versions, have been observed in crystal packing, giving diverse supramolecular motifs (Casas et al, 2004). Aulló n et al (1998) conducted a study based on the Cambridge Structural Database (Allen, 2002) involving hydrogen bonds containing M-Cl (M = transition metal), C-Cl or Cl À and either HO or HN.…”