A novel hybrid terpyridine-pyrimidine ligand and the supramolecular structures of two of its complexes with Zn(II) and acetylacetonato: The underlying role of non-covalent pi ... pi contacts and C-H...X(O, N, pi ) hydrogen bonds

The novel 4'-[4-(pyrimidin-5-yl)phenyl]-4,4':6',2 double prime -terpyridine (L1) ligand reacts with Zn(acac) sub(2) (acac = acetylacetonato) to give the monomeric complex [Zn(acac) sub(2)(L1) sub(2)] (1) and the coordination polymer [Zn(acac) sub(2)( mu -L1)] sub(n) (2). The structure of 1 consists of a Zn(II) cation sitting on an inversion centre, surrounded by a slightly elongated octahedral environment, defined by two trans N(4-pyridyl) atoms from a pair of mondentate L1 ligands, and four O atoms from two chelating acac anions. The polymeric structure of 2 presents a similar though non-symmetric Zn(acac) sub(2) unit, since the two coordinated N atoms come from two different donor moieties of L1: the 4-pyridyl and the pyrimidinyl. Both compounds present weak C-H...N contacts generating 2D aromatic structures, complemented by pi ... pi contacts plane-stacking giving raise to 3D structures and further stabilized by C-H...O and C-H... pi interactions.