Synthesis, Characterization And Properties Of Macrocyclic Compounds Containing Pyridine Diimide

In recent years, the anion recognition has been playing an important role in biological, environment, medicinal and chemical areas. The design of new receptors for selective detection of anions has received considerable attention. Based on the structural similarity between the organic ligand which contains the imide skeleton and biomacromolecule, a series of organic ligand containing imide skeleton were synthesized for simulating the inter-molecular interaction in life system. Nowadays,the research on the coordination between the organic ligand and anion is becoming a challenging topic.In this paper, we have designed and synthesized Schiff-base macrocycles, the Schiff base ligand and its complexes. Furthermore, a preliminary research on the target product has been conducted.This paper mainly focus on the following aspects:1. Synthesis of the Schiff base macrocycles and Schiff-base ligand(1) Synthesis of the flexible macrocycle L1 containing pyridine-2,6-dicarboxamide unitThe [1+1] Schiff base macrocyclic compound L1 has been synthesized via the condensation of dialdehyde Q1 with alkoxy chain bridged and diamine A1 in the presence of sulfuric acid. Then, it was reduced to the corresponding saturated macrocycle L2.(2) Synthesis of the rigid macrocycle L3 containing pyridine-2,6-dicarboxamide unitThe rigid dialdehyde Q2 was designed and synthesized. Then, the [1+1] rigid macrocycle L3 was obtained via the condensation of dialdehyde Q1 and diamine Q2 under highly dilute conditions. What’s more, we have obtained its asymmetric adduct L4 and its copper complex.(3) Synthesis of the N’-(2,4-dihydroxy benzylidene) isonicotiohydrazide L and its complexesThe Schiff base ligand L containing imide structure was synthesized form2,4-hydroxybenzaldehyde and isoniazid. when it coordinated with Zn(II), we obtained its complexes 1 and 2.2. Characterization of the Schiff base macrocycles and complexes(1)The composition of the Schiff-base target products(L1, L2, L3 and so on) were characterized by 1H NMR, IR, MS spectra and elemental analysis respectively. Their crystal structures were determined by the X-ray diffraction analysis.(2) The composition of complexes 1 and 2 were characterized by XRD, and their thermal stability were also determined.3. The study of the reaction between the macrocyclic compound L1,L2、L3 with a series of anionsThe recognition ability for a series of anions was surveyed by UV-vis absorption spectra technique, the results showed that L2 displayed a obvious recognition for Fion, L3 displayed selective recognition for both F- and pyrophosphate.4. The research on methanol adsorption of schiff base and complexes(1)The methanol adsorption properties of macrocycle L1, L2, L3 was determined by the experiment of gas adsorption, the results showed that the methanol capacity of macrocycle L3 was the highest, followed by the macrocycle L1 、L2.(2)The methanol adsorption properties of complexes 1 、 2 was determined by the experiment of gas adsorption,the results showed that the complex 1 has an advantage over the complex 2 on the capacity for methanol.