A new family of N^sub x^O^sub y^ pyridine-containing macrocycles: Synthesis and characterization of their Y(III), Ln(III), Zn(II), and Cd(II) coordination compounds

• Published in: Canadian journal of chemistry Vol. 82; no. 3; p. 437
• Main Authors: Lodeiro, Carlos, Bastida, Rufina, Bertolo, Emilia, Rodriguez, Adolfo
• Format: Journal Article
• Language: English
• Published: Ottawa Canadian Science Publishing NRC Research Press 01-03-2004
• Subjects: Cations; Chemical compounds; Chemical reactions; Chemical synthesis; Ions; Mass spectrometry; Metal complexes; Molecules; Spectrum analysis
• ISSN: 0008-4042; 1480-3291

Reaction between 2,6-bis(2-formylphenoxymethyl) pyridine and N,N-bis(3-aminopropyl) methylamine or tris(2-aminoethyl)amine has been used as the starting point for the synthesis of seven oxa-aza macrocyclic ligands, five of them never reported previously. They all feature different pendant arms, which provide a wide range of coordination possibilities. The Schiff base macrocycles L^sup 1^ and L^sup 4^ and their reduced ligands L^sup 2^ and L^sup 5^ are derived from 2,6-bis(2-formylphenoxymethyl)pyridine and tris(2-aminoethyl)amine or N,N-bis(3-aminopropyl)methylamine, respectively. The reaction of L^sup 1^ with salicylaldehyde forms L^sup 3^, which features an imine bond in the pendant arm. The ligand L^sup 5^ has been the precursor for the pendant-armed L^sup 6^ and L^sup 7^, by alkylation of the free NH groups with methyl-imidazole or methyl-indole. By a template or a nontemplate approach, we have synthesized different momo- and dinuclear complexes with Y(III), Ln(III), Zn(II), and Cd(II) cations. Both the free macrocyclic ligands and their corresponding metal complexes have been characterized by microanalysis, IR, UV-vis, ^sup 1^H and ^sup 13^C NMR spectroscopy, FAB mass spectrometry, MS electrospray, and conductivity measurements. [PUBLICATION ABSTRACT] Key words: Schiff-base macrocycle, template synthesis, macrocyclic ligand complexes, lanthanide(III) complexes.