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Updated: Oct 29, 2025
Hydrolysis of a Ni-Schiff-Base Complex Using Conditions Suitable for Retention of Acid-labile Protecting Groups
Published on: April 6, 2017
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.
Abstract:
The controlled preparation of chiral emissive transition metal complexes is fundamental in the field of circularly polarized luminescence (CPL) active molecular materials. For this purpose, enantiopure Zn(ii) complexes 1 and 2 based on a tetradentate salen ligand surrounded by [4]helicene moieties, together with their racemic counterpart 3, have been herein synthesized. Chirality is primarily brought about by chiral 1,2-cyclohexane-diamines. Alternatively, achiral complex 4 based on ortho-phenylene-diamine has been prepared as well. Single crystal X-ray diffraction analyses have been performed on helicenic intermediates 8 and 9 and complexes 1 and 4. Complexes 1 and 4 display the typical tetradentate O,N,N,O coordination around Zn(ii) characteristic of salen ligands, and bear two [4]helicene moieties. The zinc complexes are luminescent in the visible range around 560 nm at room temperature in aerated solutions with the QY reaching ca. 15% for a luminescence lifetime of 5.5 ns. The optical activities of these complexes have been assessed by CD and CPL, and compared to DFT calculations.
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