Propane-1,2-diammonium bis(pyridine-2,6-dicarboxylato-κ³O,N,O′)nickelate(II) tetrahydrate

Abstract

The reaction of nickel(II) nitrate hexa­hydrate, propane-1,2-diamine and pyridine-2,6-dicarboxylic acid in a 1:2:2 molar ratio in aqueous solution resulted in the formation of the title compound, (C3H12N2)[Ni(C7H3NO4)2]·4H2O or (p-1,2-daH2)[Ni(pydc)2]·4H2O (where p-1,2-da is propane-1,2-diamine and pydcH2 is pyridine-2,6-dicarboxylic acid). The geometry of the resulting NiN2O4 coordination can be described as distorted octa­hedral. Considerable C=O⋯π stacking inter­actions are observed between the carboxyl­ate C=O groups and the pyridine rings of the (pydc)2− fragments, with O⋯π distances of 3.1563 (12) and 3.2523 (12) Å and C=O⋯π angles of 95.14 (8) and 94.64 (8)°. In the crystal structure, a wide range of non-covalent inter­actions, consisting of hydrogen bonding [O—H⋯O, N—H⋯O and C—H⋯O, with D⋯A distances ranging from 2.712 (2) to 3.484 (2) Å], ion pairing, π–π [centroid-to-centroid distance = 3.4825 (8) Å] and C=O⋯π stacking, connect the various components to form a supra­molecular structure.

A brief review on formation of (H2O)n clusters in supramolecular proton transfer compounds and their complexes

“…28). The (H 2 O) 3 cluster created by crystalline networks reported in references [36][37][38][39][40][41][42][43][44][45] coordination compounds except the one in reference [38]. All contain (H 2 O) 3 cluster with a V-shaped structure (Fig.…”