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[(DPEPhos)(bcp)Cu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst
Published on: May 21, 2019
Reversible copper(II)/(I) electrochemical potential switching driven by visible light-induced coordinated ring
Michihiro Nishikawa1, Kuniharu Nomoto, Shoko Kume
1Department of Chemistry, School of Science, The University of Tokyo, 7-3-1 Hongo, Tokyo 113-0033, Japan.
Journal of the American Chemical Society
|May 29, 2012
Summary
This study introduces a novel copper complex that converts light energy into electronic signals through light-fueled molecular rotation. This system demonstrates repeatable signal extraction by harnessing bistable states and electrochemical potential shifts.
Area of Science:
- Coordination Chemistry
- Photochemistry
- Molecular Electronics
Background:
- Intramolecular ligand rotation can be coupled to electronic states in metal complexes.
- Harnessing light energy for molecular switching requires efficient energy conversion mechanisms.
Purpose of the Study:
- To develop a metal complex system for extracting electronic signals via light-fueled intramolecular rotation.
- To investigate the relationship between electron transfer and molecular motion in a copper complex.
Main Methods:
- Synthesis of a copper(I) complex with a pyrimidine derivative and a diimine ligand.
- Electrochemical analysis using cyclic voltammetry at variable temperatures.
- Investigation of redox and rotational reaction kinetics and thermodynamics.
Main Results:
- The copper complex exhibits bistable states linked to ligand rotation, controlled by the copper oxidation state.
- Ligand rotation is frozen in the copper(I) state but active in the copper(II) state at low temperatures.
- Light and heat can drive rotation, causing a significant electrochemical potential shift (0.14 V).
- A bypass route to a metastable copper(I) state via a copper(II) intermediate was identified.
Conclusions:
- The developed copper complex represents the first system for repeatedly extracting electronic signals from light-fueled molecular rotation.
- This work provides a new molecular signaling system based on light energy conversion and electrochemical potential shifts.
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