Homochiral Zn(Ⅱ) coordination polymers with helixes constructed from semirigid lactate deriatives for circular polarization luminescence and fluorescent prober

In the presence of nitrogen heterocyclic compound 2,5-di(1 H -imidazole-1 -yl)pyridine (2,5-DIP), luminescent chiral synthons ( R )-H 3 CTA and ( S )–H 3 CTA assembled with Zn 2+ ions to obtain enantiomers [Zn(( R )-HCTA) (2,5-DIP)] n ( HU14 -R ) and [Zn(( S )-HCTA) (2,5-DIP)] n ( HU14– S )) under hydrothermal condition, respectively. Partially deprotonated ( R )-HCTA 2- anions were bridged by Zn 2+ ions to form small left-handed ( R )-HCTA-Zn chain in HU14- R , while ( S )-HCTA 2- anions and Zn 2+ ions were connected together resulting in enantiomeric right-handed chain in HU14– S . Moreover, larger left-handed ( R )-HCTA-Zn-2,5-DIP chain and right-handed ( S )-HCTA-Zn-2,5-DIP chain were found in HU14 -R and HU14– S , respectively. These helical building blocks were joined together to create a pair of 3D frameworks with dia net, which show strong fluorescent characteristic and circular dichroism response. Further tests proved that HU14 -R and HU14– S have circularly polarized light (CPL) activity and their luminescence anisotropy factors (g 1um ) at 358 nm are +0.00346 and −0.00157, respectively. Moreover, as fluorescent probes, they have high stability, reliability and interference detection rate, and detection limits are up to 2.80 × 10 −6  M for Cr 2 O 7 2− and 6.19 × 10 −6  M for MnO 4 − .