Binuclear and trinuclear complexes of exoO(2)-cyclam

Dalton Trans. 2007 Jul 21:(27):2942-8. doi: 10.1039/b701166k. Epub 2007 May 10.

Abstract

Complexes of the ligand 2,3-dioxo-1,4,8,11-tetraaza-cyclotetradecane (exoO(2)-cyclam) have been prepared of formula [M(1){M(2)(exoO(2)-cyclam)}(2)][BPh(4)](2) where M(1)M(2) = CoCo (3), ZnZn (4), MnCu (5), FeCu (6), CoCu (7), NiCu (8), ZnCu (9), and [(bipy)(2)Ru{Cu(exoO(2)-cyclam)}][NO(3)](2) (10). Complex 10 crystallised in the space group C2/c and shows Jahn-Teller distorted Cu(II) with axial nitrate ligands. The {Cu(exoO(2)-cyclam)} moiety chelates to the Ru with Ru-O distances of 2.082(5) A. Complexes 5-10 show a Cu(II)/Cu(III) redox process and additional metal-centred (6, 8, 10) processes and ligand-centred (10) processes. The electrochemical and UV-Vis spectroelectrochemical study of suggested two closely-spaced oxidations based on the Cu and Ru centres which suggests that substituted derivatives of will be of interest for enhanced charge separation in dye-sensitised solar cells. Magnetic susceptibility measurements revealed dominant antiferromagnetic coupling within the trinuclear species 3, 5-8. Complex 10 showed Curie-Weiss behaviour with weak intermolecular interactions.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Copper / chemistry
  • Crystallography, X-Ray
  • Electrochemistry
  • Heterocyclic Compounds / chemical synthesis
  • Heterocyclic Compounds / chemistry*
  • Heterocyclic Compounds / metabolism
  • Ligands
  • Magnetics
  • Models, Molecular
  • Molecular Conformation
  • Molecular Structure
  • Organometallic Compounds / chemical synthesis
  • Organometallic Compounds / chemistry*
  • Organometallic Compounds / metabolism
  • Rhodium / chemistry

Substances

  • Heterocyclic Compounds
  • Ligands
  • Organometallic Compounds
  • cyclam
  • Copper
  • Rhodium