Supramolecular Assembly Based On Schiff Base:Circular Polarization Luminescence Materials And Chiral Molecular Detection

Chirality,as one of the most common basic properties in nature,plays an important role in the normal operation of various life activities.Schiff bases are easy to prepare and they have good coordination ability,therefore,they have become one of the most concerned organic molecules in recent years.A variety of chiral supramolecular assemblies can be constructed using Schiff bases with chiral centers.As chiral supramolecular assemblies have very important application prospects in many fields,the study of the assembly process and function of chiral supramolecular assemblies has become one of the hot spots in the field of supramolecular chemistry.In this thesis,supramolecular assemblies of chiral Schiff bases,chiral Schiff bases selectively coordinated with aluminum ions to construct circularly polarized luminescence materials and the chiral molecules detection using supramolecular assemblies were systematically studied.1)Chiral Schiff base molecules formed supramolecular assemblies by noncovalent bonding.Three novel amphiphilic chiral Schiff bases were designed and synthesized,and self-assembly in different organic solvents were studied.It was found that only two of them could form supramolecular gels in acetonitrile.We also studied the microstructure of the assemblies,accumulation mode and chiral transfer of assemblies through various instruments.Studies have shown that chiral transfer can be achieved in organic gels.2)Chiral Schiff base molecules were selectively coordinated with aluminum ions to produce circularly polarized luminescence materials.Based on the previous chapter,metal ions were introduced into the system.It was found that the fluorescence intensity significantly increased in the system with coordination.However,CPL signals could be detected only in systems that coordinate with aluminum ions,and circularly polarized luminescence materials could be successfully prepared.3)Chiral molecular detection was realized by using supramolecular assembly of Schiff bases.The pairs of enantiomers were mixed with achiral 1-hydroxy-2-naphthalene formaldehyde,respectively,and then simply heated.The heated mixture was cooled to room temperature to form supramolecular assemblies.We detected a pair of mirror-symmetric CD signals.By introducing aluminum ions into the system,a pair of mirror-symmetric CPL signals could be detected in the system.Thus,the double channel detection of chiral molecules was successfully achieved.In addition,the enantiomer excess could be quantitatively detected by CD signal.