CPL Study Of Photo-controlled Diarylenyl β-diketone Rare Earth Spirochetes

Stimulus responsive circularly polarized luminescence（CPL）materials have become a topic of concern due to their wide application in 3D displays,sensor devices,optical switches,and information storage.The synthetic stimulus-responsive CPL material should have functions such as chirality,luminescence,and stimulus controllability.However,there are currently difficulties in constructing such materials,such as complicated,high costs,and weak stimulus response effects.Therefore,we use supramolecular co-assembly to design two series of lanthanide helicates in order to solve the above problems and carry out the following research:We designed and synthesized achiral bis-β-diketone ligands L₁ and L₂ with diarylethylene as the backbone,and combined with Eu³⁺ions and R-and S-bis（diphenylphosphoryl）-1,10-binaphthyl（abbreviation,R/S-BINAPO）as a chiral co-ligand through the supramolecular co-assembly platform to synthesize the triple-stranded helical product[Eu₂（L₁）₃（R/S-BINAPO）₂]（??/ΛΛ-1）and[Eu₂（L₂）₃（R/S-BINAPO）₂]（??/ΛΛ-3）.Spectral characterization combined with a semi-empirical optimization model confirmed that R/S-BINAPO successfully induced the formation of enantiomerically pure dinuclear rare earth spirochetes.Under the alternating ultraviolet-visible light irradiation,the photoisomerization phenomenon of the complexes??/ΛΛ-1and??/ΛΛ-3 effectively regulated the chirality of the ground state and excited state in the solution,and|glum|was determined by 0.099 increased to 0.133.Under light stimulation,the spirochetes realized the changes of the quadruple optical signals of CD,PL,CPL and glum and successfully fabricated molecular logic gates（MLG）.This research provided a new idea for constructing complex light modulated optical and chiral optical switch molecular logic gates.Based on the above design ofβ-diketone ligands L₁ and L₂,the chiral guanidine salt（1,3-bis（（R/S）-1-phenethyl）guanidine hydrobromide Salt）（abbreviated as R/S-pyg）as a counter ion to replace HEt₃N⁺,through ¹H NMR,HRMS and DOSY NMR,it was confirmed that the diastereomerically pureΔΔ/ΛΛ-（R/S-pyg）₂⁺[Eu₂（L₁）₄]^2-（??/ΛΛ-2）andΔΔ/ΛΛ-（R/S-pyg）₂⁺[Eu₂（L₂）₄]^2-（??/ΛΛ-4）.Semi-empirical theoretical calculations and ¹H-¹H ROESY NMR spectra proved the intermolecular interactions between chiral guanidine salts and achiral ligands.The mirror image CD and CPL spectra further proved that chiral counterions have successfully induced supramolecular helix chirality.In addition,spirochetes exhibit light-regulated CPL properties under alternating ultraviolet and visible light irradiation.Under light steady state,|glum|increased from 0.067 to 0.086.This research provided a new way to synthesize excellent stimulus-responsive circularly polarized luminescent materials.