Metal complexes with four macrocyclic ligands derived from 2,6-bis(2-formylphenoxymethyl)pyridine and 1,7-bis(2′-formylphenyl)-1,4,7-trioxaheptane

Abstract

New series of [1+1] Schiff-base macrocyclic complexes have been prepared by reaction between 1,5-bis(2-aminophenoxy)-3-oxapentane and 2,6-bis(2-formylphenoxymethyl)pyridine (L 1) or 1,7-bis(2′-formylphenyl)-1,4,7-trioxaheptane (L 3), using the metal salts of Co(II), Ni(II), Ag(I), Zn(II) or Pb(II) as template agents. Treatment of both diiminic ligands with NaBH 4 gives the corresponding reduced macrocycles L 2 and L 4; the complexation capacity of both reduced ligands towards Co(II), Ni(II), Ag(I), Zn(II) and Pb(II) ions has been also investigated. The complexes have been characterised by elemental analyses, molar conductivity, mass spectrometry, IR, UV–Vis and 1H NMR spectroscopy, diffuse reflectance and magnetic measurements.