Tri-Nuclear Phthalocyanine Complexes Carrying N/O Donor Ligands as Hydrogen Peroxide Catalysts, and Their Bleaching Activity Measurements by an Online Spectrophotometric Method

Abstract

A phthalocyanine (4) with four salicylhydrazone ligating groups that are directly linked through oxygen bridges to the macrocyclic core has been synthesized by condensation of tetrakis(4-formylphenoxy)phthalocyaninato zinc(II) (3) with salicylhydrazine. Salicylhydrazine was crystallized in methanol during the synthetic procedure. The crystal structure has triclinic space group P-1 with a=5.8292(6) angstrom, b=7.3039(7) angstrom, c=17.9798(18) angstrom, =84.272(8)degrees, =89.184(8)degrees, =81.469(8)degrees, and Z=4. Intramolecular O-HO and intermolecular O-HO, N-HN, N-HO hydrogen bonds were determined in the crystal structure. In addition, there is a weak C-H interaction. Complexation on the periphery to yield tri-nuclear Zn(II)Pcs (5-7) was performed through the reaction of a Schiff base-substituted phthalocyanine (4) with MnCl(2)4H(2)O, CoCl(2)6H(2)O, or Ni(OAc)(2) salts. Fourier transform infrared, H-1 NMR, C-13 NMR, UV-Vis, ICP-OES (inductively coupled plasma optical emission spectroscopy), mass spectroscopies, and elemental analyses were applied to characterize the prepared compounds. Bleach catalyst activity of the prepared phthalocyanine complexes (5-7) was examined by the degradation of morin and curcumin, respectively. The catalysts had better activity for color removing in solutions at ambient temperature than to that of tetraacetylethylenediamine (TAED). [GRAPHICS]