Configuration Transformation And Properties Of Coordination Polymers Based On Amino DBd Ligand

Aminocarboxylic acid ligands have the advantages of diverse coordination modes and easy functionalization,and are often used to construct metal-organic complexes.Due to the existence of amino groups,the complexes constructed can be post-synthetically modified to impart new functions.In this paper,six coordination polymers（CPs）were constructed using the amino carboxylic acid ligand4,4-diaminobiphenyl-2,2-dicarboxylic acid（DBd）,[Zn₂（DBd）₂（H2O）₂]H₂O（1）,Pb（DBd）（2）,[Cd（DBd）（H₂O）]3H₂O（3）,[Cu（DBd）H₂O]2H₂O（4）,[Co₄（DBd）₄（H₂O）₄]·2H₂O（5）,[Co（DBd）₂（H₂O）₂]·2H₂O（6）,and 9 post-modification products were obtained by post-synthesis modification.The main contents of this paper are as follows:1.Post-modification of the complex:1 was post-modified with an aldehyde-based TPE molecule（TPE-CHO）with AIE properties to obtain a complex（TPE-1）with AIE properties.1 was post-modified with 3-formylbenzoic acid（Q1）,3-formyl-2-hydroxybenzoic acid（Q2）,2,3,4-trihydroxybenzaldehyde（Q3）containing carboxyl and hydroxyl groups,Three post-modification products Q1-1,Q1-2 and Q3-1 were obtained.3 was modified by halogen-containing5-bromo-2-hydroxybenzaldehyde（Q4）,3,5-dibromo-2-hydroxybenzaldehyde（Q5）,5-chloro-2-hydroxybenzaldehyde（Q6）,5-fluoro-2-hydroxybenzaldehyde（Q7）,four post-modified products Q4-3,Q5-3,Q6-3 and Q7-3 were obtained.Complex 6 was modifiedwithtri-linked5’-（4-formylphenyl）-[1,1’:3’,1’’-terphenyl]-4,4’’-dicarbaldehyde（Q8）to give a post-modification product Q8-6 was developed to explore the possibility of CPs forming metal covalent organic frameworks through post-modification.2.Single crystal structure transformation and difference in properties:The study found that there is a single crystal to single crystal transformation phenomenon（SCSC）between complexes 1-3.The SCSC conversion process between 1 and 3 was studied using kinetics and thermodynamics.The water vapor adsorption and proton conductivity properties of 1-3 and the proton conductivity properties of the post-modified products Q1-1,Q2-1 and Q3-1 were further measured,and the relationship between the structural transition and the properties of the complexes was explored.3.Study on the luminescence properties:Based on the characteristics of the complexes,we explored the potential properties of 1 and its modified product TPE-1in terms of fluorescence.The fluorescence properties of 3 and its post-modified products Q4-3,Q5-3,Q6-3 and Q7-3 were measured,and the effect of modifiers on the fluorescence properties of post-modified products was studied.