Octaakis(4-aminopyridine)-1κ⁴N¹,2κ⁴N¹-aqua-2κO-μ-carbonato-1:2κ³O,O′:O′′-dinickel(II) dichloride pentahydrate

Abstract

In the title compound, [Ni2(CO3)(C5H6N2)8(H2O)]Cl2·5H2O, one of the the NiII ions is six-coordinated in a distorted octa­hedral geometry, with the equatorial plane defined by four pyridine N atoms from four amino­pyridine ligands, the axial positions being occupied by one water O and a carbonate O atom. The other NiII ion is also six-coordinated, by four other pyridine N atoms from four other amino­pyridine ligands and two carbonate O atoms to complete a distorted octa­hedral geometry. In the crystal structure, mol­ecules are linked into an infinite three-dimensional network by O—H⋯O, N—H⋯Cl, N—H⋯O, O—H⋯N, C—H⋯O, C—H⋯N and C/N—H⋯π inter­actions involving the pyridine rings.

Novel Coordination Polymers of Metal(II) Succinates with 4‐Aminopyridine: Synthesis, Spectroscopic, Thermal, and Fluorescent Properties

“…The intrachain Ni–Ni distance separated by the suc ligands is 8.944 Å shorter than {[Ni(H 2 O) 2 (nia) 2 (μ‐suc)] · 2H 2 O} n , which is 9.401 Å, and [Ni(H 2 O) 4 (suc)] n , which amounts 9.733 Å. The Ni–O suc and Ni–O w distances [2.057(2) and 2.094(2) Å] are similar to those of the corresponding nickel(II) complexes, [15–18] and the Ni–N distance of 2.113(2) Å is similar to those reported for the Ni II carbonato complexes of apy 19. The C–O bond lengths of the coordinated and non‐coordinated oxygen atoms of suc are almost the same (1.259–1.256 Å), respectively, due to delocalization of the negative charge between them.…”

“…On the other hand, upon excitation at 350 nm, compound 4 emits intense violet luminescence at 418 nm. The emission maxima are 46019 and 530 nm for free apy and 462 and 562 nm for free H 2 suc after excitation at 350 nm. The emission spectra of complex 4 , free apy, and H 2 suc in the solid state at ambient temperature are shown in Figure 4 (λ ex = 350 nm).…”