Syntheses, characterization, crystal structures and fluorescence property of Zinc(II) complexes with Schiff bases

Resumo

Two new mononuclear Schiff base zinc(II) complexes, [ZnCl₂(L¹)] ∙ MeOH (I) and [Zn(L²)₂] (II) (L¹ = 2-bromo-4-chloro-6-[(2-ethylammonioethylimino)methyl]phenolate; L² = 2-bromo-4-chloro-6-(isopropyliminomethyl)phenolate), have been prepared and characterized by elemental analyses, infrared and UV-Vis spectroscopy, and single-cyrstal X-ray diffraction (CIF files CCDC nos. 1408962 (I), 1408961 (II)). Complex I crystallizes in the triclinic space group \(P\overline 1\) with unit cell dimensions a = 9.859(1), b = 13.015(2), c = 19.817(3) Å, α = 73.591(2)°, β = 76.032(2)°, γ = 82.966(2)°, V = 2363.0(5) ų, Z = 4, R₁ = 0.0925, and wR₂ = 0.2257. Complex II crystallizes in the monoclinic space group P2₁/c with unit cell dimensions a = 7.6387(7), b = 22.307(2), c = 21.443(2) Å, β = 96.216(3)°, V = 3632.4(6) ų, Z = 8, R₁ = 0.0651, and wR₂ = 0.1100. The both Zn atoms in I is four-coordinated in a tetrahedral geometry by the NO donor set of the Schiff base ligand, and two Cl ligands. The Zn atom in II is in a tetrahedral geometry by two N and two O atoms from two Schiff base ligands. Crystals of the complexes are stabilized by hydrogen bonds and weak π…π interactions. Fluorescence property of the complexes have been determined.