Ligand Influence over the Formation of Dinuclear [2+2] versus Trinuclear [3+3] Cu-I Schiff Base Macrocyclic Complexes

Arbuse A, Mandal S, Maji S, Martinez MA, Fontrodona X, Utz D, Heinemann FW, Kisslinger S, Schindler S, Sala X, Llobet A (2011)

Publication Status: Published

Publication Type: Journal article

Publication year: 2011

Journal

Inorganic Chemistry American Chemical Society

Publisher: AMER CHEMICAL SOC

Book Volume: 50

Pages Range: 6878-6889

Journal Issue: 15

DOI: 10.1021/ic102185y

Abstract

The preparation and characterization of three new macrocyclic ligands with pendant arms based on the [2+2] condensation of isophthalaldehyde and the corresponding triamine substituted at the central N-atom is reported. None of these new macrocyclic ligands undergo any equilibrium reaction, based on imine hydrolysis to generate [1+1] macrocyclic formation or higher oligomeric compounds, such as [3+3], [4+4], etc., at least within the time scale of days. This indicates the stability of the newly generated imine bond. In sharp contrast, the reaction of the [2+2] macrocyclic Schiff bases with Cu-I generates the corresponding dinuclear Cu-I complexes [Cu-2(L-1)](2+); 1(2+); [Cu-2(L-2)(CH3CN)(2)](2+), 2(2+); and [Cu-2(L-3)(CH3CN)(2)](2+), 3(2+), together with their trinuclear Cu-I homologues [Cu-3(L-4)](3+), 4(3+); [Cu-3(L-5)(CH3CN)(3)](3+), 5(3+); and [Cu-3(L-6)(CH3CN)(3)](3+), 6(3+), where the [2+2] ligand has undergone an expansion to the corresponding [3+3] Schiff base that is denoted as L-4, L-5, or L-6. The conditions under which the dinuclear and trinuclear complexes are formed were analyzed in terms of solvent dependence and synthetic pathways. The new complexes are characterized in solution by NMR, UV-vis, and MS spectroscopy and in the solid state by X-ray diffraction analysis and IR spectroscopy. For the particular case of the L-2 ligand, MS spectroscopy is also used to monitor the metal assisted transformation where the dinuclear complex 2(2+) is transformed into the trinuclear complex 5(3+). The Cu-I complexes described here, in general, react slowly (within the time scale of days) with molecular oxygen, except for the ones containing the phenolic ligands 2(2+) and 5(3+) that react a bit faster.

Authors with CRIS profile

Frank Wilhelm Heinemann Lehrstuhl für Anorganische und Allgemeine Chemie

Involved external institutions

University of Girona / Universitat de Girona (UdG) ES Spain (ES) Institute of Chemical Research of Catalonia / Institut Català d'Investigació Química (ICIQ) ES Spain (ES) Justus-Liebig-Universität Gießen DE Germany (DE) Autonomous University of Barcelona (UAB) / Universitat Autònoma de Barcelona ES Spain (ES)

How to cite

APA:

Arbuse, A., Mandal, S., Maji, S., Martinez, M.A., Fontrodona, X., Utz, D.,... Llobet, A. (2011). Ligand Influence over the Formation of Dinuclear [2+2] versus Trinuclear [3+3] Cu-I Schiff Base Macrocyclic Complexes. Inorganic Chemistry, 50(15), 6878-6889. https://doi.org/10.1021/ic102185y

MLA:

Arbuse, Arnau, et al. "Ligand Influence over the Formation of Dinuclear [2+2] versus Trinuclear [3+3] Cu-I Schiff Base Macrocyclic Complexes." Inorganic Chemistry 50.15 (2011): 6878-6889.

BibTeX: Download