Related Experiment Video
Updated: Aug 11, 2026

Amide Coupling Reaction for the Synthesis of Bispyridine-based Ligands and Their Complexation to Platinum as Dinuclear Anticancer Agents
Published on: May 28, 2014
Binuclear Copper Complexes Based on the 6,6'-Bis[[bis(2-pyridylmethyl)amino]methyl]-2,2'-bipyridine Ligand
Dong-Heon Lee1, Narasimha N. Murthy, Kenneth D. Karlin
1Department of Chemistry, The Johns Hopkins University, Charles and 34th Streets, Baltimore, Maryland 21218.
Abstract:
The tripodal tetradentate ligand TMPA (tris(2-pyridylmethyl)amine) has provided a wealth of valuable new Cu(I) and Cu(II) chemistry, in particular associated with copper(I)/dioxygen reactivity studies (Karlin, K. D.; Kaderli, S.; Zuberbühler, A. D. Acc. Chem. Res. 1997, 30, 139-147). Dinucleating analogues have also been recently investigated, and here we describe new copper complexes of the 6,6'-bis[[bis(2-pyridylmethyl)amino]methyl]-2,2'-bipyridine ligand (bTMPA). The synthesis and X-ray crystallographic characterization of [(bTMPA)Cu(II)(2)(CH(3)CN)(2)(ClO(4))(2)](2+) (1, as ClO(4)(-) salt) and [(bTMPA)Cu(II)(2)(N(3))(2)(ClO(4))(2)] (2) are provided. [1: space group C2/c; a = 15.907(4) Å, b = 29.268(7) Å, c = 13.941(2) Å; beta = 97.79(2) degrees; Z = 4; volume = 6431(2) Å(3). 2: space group P2(1)/c; a = 8.118(5) Å, b = 29.743(8) Å, c = 9.120(6) Å; beta = 114.00(5) degrees; Z = 2; volume = 2012(2) Å(3).] Both solid state structures possess six-coordinate copper(II) ions, and in neither case does the 2,2'-bipyridine (bipy) moiety within bTMPA chelate to a single metal ion. Dissociation of bound perchlorate and the presence of pentacoordinate solution structures are suggested by spectroscopic (UV-vis with two d-d absorptions; axial EPR spectra) along with conductivity data (1, 1:4 electrolyte; 2, 1:2 electrolyte). Electrochemical measurements by cyclic volammetry have been carried out, and for a dicopper(I) analogue, [(bTMPA)Cu(I)(2)](ClO(4))(2) (3(ClO(4))(2)), a single quasireversible redox wave is observed; E(1/2) = +199 mV (versus Ag/AgCl in dimethylformamide), which is approximately 280 mV more positive than that observed for the simple "parent" compound [Cu(I)(TMPA)(CH(3)CN)](ClO(4)). Unlike [Cu(I)(TMPA)(CH(3)CN)](ClO(4)), 3 does not readily form dioxygen adducts.
Related Concept Videos
Metal-Ligand Bonds
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
Coordination Number and Geometry
Structural Isomerism
Isomers are different chemical species that have the same chemical formula. Structural isomerism of coordination compounds can be divided into two subcategories, the linkage isomers and coordination-sphere isomers.
Linkage isomers occur when the coordination compound contains a ligand that can bind to the transition metal center through two different atoms. For example, the CN− ligand can bind through the carbon atom or through the nitrogen atom. Similarly, SCN− can be...
Colors and Magnetism
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human eye.
Complexation Equilibria: The Chelate Effect
Complexometric Titration: Ligands
![[(DPEPhos)(bcp)Cu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F59739.jpg&w=3840&q=50)
