Microwave-assisted synthesis and characterization and theoretical calculations of the first example of free and metallophthalocyanines from salen type Schiff base derivative bearing thiophen and triazole heterocyclic rings

Abstract

Novel metal-free and metallophthalocyanine complexes of Co, Ni, Cu, and Zn have been synthesized by exposure to microwave irradiation and reflux conditions and the products purified by several techniques. The newly prepared compounds have been characterized by elemental analyses, IR, 1H NMR, MS and UV-Vis spectroscopy. Furthermore, theoretical calculations of metallophthalocyanines CuPc, NiPc, ZnPc and CoPc were carried out to comparatively describe the molecular structures, molecular orbital and UV-Vis spectra of metallophthalocyanine complexes by the HF theory. A comparison between the different molecules for the geometry, molecular orbitals was made. The simulated order of the sizes of the central hole was CoPc > NiPc < CuPc < ZnPc, which is in complete accord with the experiment. Moreover, the HOMO-LUMO gaps were varied in order of CoPc > NiPc > ZnPc > CuPc. The calculated structures, electronic absorption spectra of metallophthalocyanine complexes are in good consistency with the experimental results. © 2007 Elsevier B.V. All rights reserved.