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Updated: Oct 29, 2025
06:44
Hydrolysis of a Ni-Schiff-Base Complex Using Conditions Suitable for Retention of Acid-labile Protecting Groups
Published on: April 6, 2017
9.9K
Schiff-base [4]helicene Zn(II) complexes as chiral emitters.
Mariia Savchuk1, Steven Vertueux1, Thomas Cauchy1
1Univ Angers, CNRS, MOLTECH-Anjou, SFR MATRIX, F-49000 Angers, France. nicolas.zigon@univ-angers.fr narcis.avarvari@univ-angers.fr.
Dalton Transactions (Cambridge, England : 2003)
|July 14, 2021
Summary
Researchers synthesized chiral zinc(II) complexes with [4]helicene moieties for circularly polarized luminescence (CPL) applications. These novel materials exhibit luminescence and optical activity, paving the way for advanced CPL molecular materials.
Area of Science:
- Coordination Chemistry
- Materials Science
- Photophysics
Background:
- Chiral emissive transition metal complexes are crucial for circularly polarized luminescence (CPL) active molecular materials.
- The controlled synthesis of enantiopure complexes is essential for developing advanced CPL applications.
Purpose of the Study:
- To synthesize enantiopure and racemic Zn(II) complexes incorporating [4]helicene moieties for CPL studies.
- To investigate the structural, luminescent, and optical properties of these novel complexes.
Main Methods:
- Synthesis of chiral Zn(II) complexes (1, 2, 3) and an achiral analogue (4) using tetradentate salen ligands and [4]helicene units.
- Single crystal X-ray diffraction for structural analysis of intermediates and complexes.
- Photoluminescence spectroscopy (emission spectra, quantum yield, lifetime) and optical activity measurements (CD, CPL).
- Density Functional Theory (DFT) calculations for property comparison.
Main Results:
- Successful synthesis of enantiopure Zn(II) complexes (1, 2) and their racemic counterpart (3), along with achiral complex (4).
- Structural characterization confirmed the tetradentate O,N,N,O coordination of salen ligands and the presence of [4]helicene moieties.
- Complexes 1 and 4 exhibit visible luminescence (around 560 nm) with a quantum yield up to 15% and a luminescence lifetime of 5.5 ns.
- Optical activity was assessed and correlated with DFT calculations.
Conclusions:
- The synthesized chiral Zn(II) complexes are promising candidates for CPL active molecular materials.
- The study demonstrates a viable synthetic route to chiral metal complexes with [4]helicene substituents for CPL applications.
- Further investigation into structure-property relationships can optimize CPL performance.
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