NMR investigations of the solution structures of Ru-Zn complexes tethered by oligo(aminoethylglycine) chains

作者：Myers Carl P; Sun Sha; Showalter Scott A; Miller James R; Williams Mary Elizabeth^*

来源：Polyhedron, 2012, 40(1): 118-124.

DOI：10.1016/j.poly.2012.02.030

• NMR
• Ru
• Heterometallic

[Ru(bpy)(3)](2+) complexes derivatized with two aminoethylglycine (aeg) chains bearing pendant bipyridine ligands coordinate Zn2+ to form a coordinative interchain crosslink. Although [Zn(bpy)(2)](2+) is both redox and spectroscopically silent, when bound to [Ru(bpy)(3)](2+) by the aeg strands it causes quenching of the emissive Ru complex excited state. H-1 NMR spectroscopy is used to monitor changes in the structure and environment of the Ru complex during a titration as Zn2+ is added. Using spectral assignments from 1 and 2D NMR spectra, the spectrophotometric titrations reveal that Zn2+ binding causes significant shifts of the peaks assigned to the protons on the [Ru(bpy)(3)](2+) core that are closest to the Zn2+. These shifts reveal changes in the local environment that are likely a combination of electrostatic interactions between the two dication metal complexes and strain induced by the metal ion crosslinking the strands.

• 出版日期2012-6-19