The Research On The Self-assembly Behaviors Of Several Synthetic Porphyrin Derivatives

Self-assembly,one of the most important research topics in supramolecular chemistry,provides efficient avenues for constructing functional supramolecular systems.As well known,the abilities of supramolecular materials are seriously depended on the building blocks and their assembly modes.Benefitting from the strongπ-πstacking,rich modification sites,various coordination properties and sensitive photoelectric property,porphyrins,a famous building block,have been widely utilized to construct functional supramolecular assemblies.In this paper,a series of porphyrins derived from phenylalanine and pyridine were designed and synthesized,thereafter their self-assembly behaviors were investigated.The main contents of this paper are as follows:1.The development and research status of supramolecular chemistry are briefly introduced,and the research results of porphyrin derivatives in chiral molecular assembly and metal coordination assembly are reviewed.2.The meso-position trans-substituted porphyrins（D/L-PP）derived from D/L-phenylalanine and phenylcarboxyl were designed and synthesized,which were fully characterized by ¹H NMR,¹³C NMR and HRMS.Subsequently,the self-assembly properties of D/L-PP were investigated by UV and circular dichroism spectra in various p H conditions.The results indicated that D/L-PP cannot form regulated assemblies in neutral and alkaline solution conditions,mainly due to theπ-πstacking and hydrogen bond were destroyed by electrostatic interactions.In weak acidic solution,strong chiral signals are induced,and J-aggregation is dominant.This work provides theoretical basis and experimental model for the design and development of intelligent chiral materials.3.Based on the electrostatic interaction between pyridine cation and carboxylic acid,two kinds of azo-modified pyridinium salts were designed and synthesized,and the assembly performance and photostimulation response of the two pyridinium salts to D/L-PP at different p H conditions were investigated by UV and circular dichroism spectra.The data show that the supramolecular chiral amplification and inversion can be successfully achieved by tuning the p H of solution and controlling the photoisomerization of azobenzene moiety.This work has successfully achieved chiral amplification and chiral inversion,providing a theoretical basis for the design and development of intelligent chiral materials.4.Three pyridine group modified porphyrin derivatives were designed and synthesized,and six coordination polymers were obtained by coordination with Pd（Ⅱ）and Fe（Ⅱ）metal ions.The basic characterization was carried out by SEM,FT-IR,TGA and BET tests.The results showed that these coordination polymers were structurally stable multi-pore organic materials.Subsequently,through the electrochemical oxygen reduction test,it was found that the metal polymer with Pd coordination had well ORR electrocatalytic activity.This work provides ideas for the preparation of highly efficient oxidant catalysts in the future.