Synthesis and crystal structure of a new nickel(II) coordination polymer based on Schiff base

A new Schiff base coordination polymer, [Ni(C18H16N3O2)2 · 2CH3OH]n (C18H16N3O2, 2-acetylpyridine-L-tryptophan), was synthesized and characterized by IR, UV, and X-ray diffraction singlecrystal analysis. The crystal crystallizes in the tetragonal crystal system, space group P43212 with cell parameters a = 11.8912(11), c = 28.822(3) Å, V = 4075.5(6) Å3, Z = 4, F(000) = 1544, S = 1.187, ρcalcd = 1.199 g cm−3, μ = 0.525 mm−1, the final R1 = 0.0515 and wR2 = 0.1513 for 3602 observed reflections (I > 2σ(I)). The Ni(II) atom is six-coordinated by two nitrogen atoms from C=N, two nitrogen atoms from pyridine rings and two carboxylic oxygen atoms in different ligands, forming a distorted octahedron geometry. Each ligand serves as a bridging ligand to link Ni2+ ions through carboxylic oxygen atoms, leading to a two-dimensional coordination polymer.