Related Experiment Video
Updated: May 19, 2026

Thermochemical Studies of Ni(II) and Zn(II) Ternary Complexes Using Ion Mobility-Mass Spectrometry
Published on: June 8, 2022
Differential sensing of Zn(II) and Cu(II) via two independent mechanisms
1Department of Chemistry, University of South Dakota, Vermillion, South Dakota 57069, United States.
Abstract:
Selective reduction of an anthracenone-quinoline imine derivative, 2, using 1.0 equiv of NaBH(4) in 95% ethanol affords the corresponding anthracen-9-ol derivative, 3, as confirmed by (1)H NMR, (13)C NMR, ESI-MS, FTIR, and elemental analysis results. UV-vis and fluorescence data reveal dramatic spectroscopic changes in the presence of Zn(II) and Cu(II). Zinc(II) coordination induces a 1,5-prototropic shift resulting in anthracene fluorophore formation via an imine-enamine tautomerization pathway. Copper(II) induces a colorimetric change from pale yellow to orange-red and results in imine hydrolysis in the presence of water. Spectroscopic investigations of metal ion response, selectivity, stoichiometry, and competition studies all suggest the proposed mechanisms. ESI-MS analysis, FTIR, and single-crystal XRD further support the hydrolysis phenomenon. This is a rare case of a single sensor that can be used either as a chemosensor (reversibly in the case of Zn(II)) or as a chemodosimeter (irreversibly in the case of Cu(II)); however, the imine must contain a coordinating Lewis base, such as quinoline, to be active for Cu(II).
More Related Videos
11:04Ion Mobility-Mass Spectrometry Techniques for Determining the Structure and Mechanisms of Metal Ion Recognition and Redox Activity of Metal Binding Oligopeptides
Published on: September 7, 2019
09:22Synthesis and Performance Evaluations of ZnCoS/ZnCdS with Twin Crystal Structure for Multifunctional Redox Photocatalysis in Energy Applications
Published on: July 25, 2025
Related Concept Videos
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.
Electrochemical Systems
Ladder Diagrams: Complexation Equilibria
The formation constant, K1, for the formation of Cd(NH3)2+ complex from cadmium and ammonia is 3.55 × 102. Log K1 (i.e. pNH3) is 2.55, and...
Extraction: Advanced Methods
Precipitation and Co-precipitation
Valence Bond Theory