Triazolate-containing macrocyclic transition-metal complexes derived from bis(3-aminopropyl)amine and 3,5-diacyl-1,2,4-triazoles

Abstract

Template 1:1 condensation of 3,5-diacetyl- or 3,5-diformyl-1,2,4-triazole with bis(3-aminopropyl)amine in the presence of 1 equivalent of LiOH and M(ClO₄)₂(M = Ni, Cu, Co or Pb) produces mononuclear tetraaza 14-membered macrocyclic Schiff-base metal(II) complexes [ML]ClO₄{L = 12-hydroxy-2,12-dimethyl- or 12-hydroxy-3,7,11,14,15,16-hexaazabicyclo[11.2.1]hexadeca-2,13,15-trienate}. These compounds are derived from the expected diimino macrocyclic complexes by formal addition of water across one of the azomethine bonds. Reduction of the Schiff-base complexes with sodium tetrahydroborate provides the corresponding saturated tetraaza macrocyclic complexes. Both sets of compounds were identified and studied by liquid secondary ion mass spectrometry.