摘要:
Herein we report the syntheses and structural analyses of coordination compounds derived from 2-(2-benzothiazolylamino)benzothiazole, bis-btz (1), 2-(2-aminobenzothiazolylamino)benzoxazole, btz-boz (2) and 2-(2-benzothiazolylamino) benzimidazole, btz-bz (3). Ligands 1-3 are aromatic heterocycles prepared from 2-aminobenzothiazole that differ by the heteroatom (S, O, N) at position 12. These heterocycles were reacted with cobalt(II), nickel(II), and zinc(II) acetates; in addition, ligand I with mercury(II) acetate. The coordination compounds were characterized in the solid state by UV-Vis-NIR reflectance spectra, IR, X-ray diffraction and mass spectrometry. Unusual electronic spectra of Co2+ and Ni2+ compounds, indicated the participation of the metal ion in the ligand electronic delocalization. The N-H group was, in all cases, deprotonated and coordination to the metal ion occurs through the nitrogen atoms N(3) and N(13), forming a six-membered ring in a planar pentacyclic aromatic system. A distorted tetrahedral geometry is stabilized for ML2 complexes (M2+ = Co, Ni, Zn; L = 1-3) and for the (bis-btz)(2)Hg2+ compound, while nickel in [Ni(btz-bOZ)(2)(MeOH)] is square pyramidal and octahedral in [Ni(L)(OAc)(MeOH)(2)] (L = 1-3). Solid state structures showed 1D and 2D supramolecular arrangements. (c) 2006 Elsevier Ltd. All rights reserved.