Synthesis,Characterization And Theoretical Analysis Of Nitroaromatic Hydrazide And Their Derivatives

Aromatic heterocyclic compounds are an significant part of modern organic chemicals,which are widespread applied to dyes,photosensitive materials,antioxidants,rubber vulcanizing agents and other fields.The introduction of hydrazide and oxadiazole in aromatic rings can expand the conjugated system,which is conducive to intramolecular charge transfer,so such compounds often have excellent optical properties and electron transport performance.At the same time,these compounds contain multiple oxygen and nitrogen heteroatoms,which can be used as organic ligands and metal ions to form organometallic complexes with diverse structures and excellent properties.In this paper,starting from the synthetic route,using8-aminoquinoline,2-chlorouracil and nitrobenzene as organic raw materials,through hydrazination,acylation,cyclization reaction to prepare a series of aromatic heterocyclic hydrazine and oxadiazol one,and using it as an organic ligand and Cu（Ⅰ）reaction to prepare metal organic complex,the structure and properties of the synthesized substance were studied.The main research contents are as follows:1.Using 8-aminoquinoline,2-chlorouracil and nitrobenzene as initial raw materials,four new organic compounds were designed and synthesized through hydrazination,acylation and ring formation reactions:4-nitro-N’-（8-quinolin-yl）benzohydrazide（1）,5-（4-nitrophenyl）-3-（quinolin-8-yl）-1,3,4-oxadiazol-2（3H）-one（2）,4-nitro-N’-（pyrimidin-2-yl）benzohydrazide（3）,5-（4-nitrophenyl）-3-（pyrimidin-2-yl）-1,3,4-oxadiazol-2（3H）-one（4）.The structure and purity of the prepared compounds were characterized by MS,HPLC,IR,¹H NMR and ¹³C NMR.2.Explore the thermal and optical properties of compounds 1-4.By studying the UV spectra of the four compounds,it was found that the R band of compounds 2-4 had UV recognition performance on Fe³⁺.Therefore,the UV enhancement effect and anti-ion interference ability of compounds 2-4 on Fe³⁺concentration were further studied,and the linear fitting equation and detection limit（LOD）were obtained as follows:1.99×10^-6mol/L,7.68×10^-6mol/L,6.92×10^-6mol/L。The solid fluorescence test of the four compounds showed that all of them could emit purple fluorescence,and the quinoline derivatives had higher luminous intensity than the pyrimidine derivatives.Meanwhile,the thermogravimetric analysis results also showed that the four compounds had no mass loss before 170℃,and the structure was stable.Therefore,the four organic compounds could be used as organic fluorescence materials.Taking compound 2 as an example,the influence of solvent effect on fluorescence emission wavelength was further studied,and the ability of compound 2-4 as a fluorescent probe to detect metal ions was also investigated.It was found that Fe³⁺had fluorescence enhancement effect on compound 2,but its resistance to other ions was weak.Fe³⁺has fluorescence quenching effect on compounds 3 and 4 and strong anti-interference ability.Therefore,compounds 3 and 4 can be used as fluorescent probes to detect low concentrations of Fe³⁺and obtain linear fitting equation and corresponding LOD,6.11×10^-6mol/L,6.06×10^-6mol/L。3.A new metal-organic complex was synthesized with Cu（Ⅰ）using compound 2 as organic ligand（1）:Cu（NO₂PQOO）（Cl）（1）,（NO₂PQOO=compound 2）,the structure of the complex was characterized,and its thermal and electrical properties were tested and analyzed.The results showed that complex 1 had excellent thermal stability and showed relatively good catalytic capacity for NO₃^-electrochemical reduction.4.The second order nonlinear optical（NLO）properties of compounds 1-4 were studied theoretically,and their molecular configurations,molecular frontier orbitals,state densities,the first hyperpolarizability.