Construction And Property Modulation Of Fluorescent Gel Based On Terpridine Derivatives

Metallogels are currently a hugely important class of materials with unique multiple functions,such as photoelectrical properties and magnetism,etc.As an NNN-type Pincer ligand,the 2,2':6',2''-terpyridine plays an important role in coordination chemistry.Terpyridine-based gelators have been designed and synthesized.The microscopic molecular assembly and macroscopic properties of the gel are tunable by specific ion.In this article,we mainly introduce the following content:1)A polydentate ligand TC containing terpyridine and carboxylic acid units was designed which showed different macroscopic properties through multiple aggregation modes.In the presence of different kind of Zn²⁺ions or NaOH,TC could form hydrogels and crystals via?-?stacking and metal-ligand interaction.Moreover,these TC/Zn²⁺hydrogels could transform to soluble and fluorescent aggregates in the presence of NaOH due to the formation of binuclear metallo-coordination polymers.The metal-ligand interactions tuned by different metal salts in gels,crystals,and sols were also studied and illustrated in detail,it was also proved that water was an essential linker for constructing Na+-based metallo-complexes from the TC/NaOH crystal data.2)A ligand that can form a hydrogel with ions has been synthesized start from terpyridine group,lysine and ethylenediamine units.The gel has special fluorescent properties in the presence of Al³⁺and Zn²⁺,and can be used as an Al³⁺ion sensor.The phase,fluorescence,mechanical properties and assembly process of metal complexes are tunable by ion concentration.