Synthesis And Properties Of Dithiophene Pyridine Complexes And Triazine Materials

By using different organic linkers,including cyanide,azide,nitrogen-containing aromatic ligands,etc.,combining different metals to obtain specific physical characteristics and chemical functions,thereby building an extended architecture.In this paper,we mainly synthesize a nitrogen-containing ligand and coordinate it with a transition metal to prepare the corresponding metal complex,and study the structure and properties of the metal complex.Among them,the complex with photoluminescence after coordination with Mn(II)and the complex with Pd(II)have good catalytic performance in Heck coupling reaction.At the same time,we also synthesized biimidazole-type functional triazine materials and successfully applied them in the catalytic reaction of epoxides and CO₂ to produce cyclic carbonates?First,we use a one-pot method to obtain bisthienopyridine ligands containing amino groups,which are bithpy-1 and bithpy-2,respectively.Using these as high-efficiency ligand precursors,the bisthienopyridine ligand(bithpy)The corresponding metal complexes are prepared by refluxing condensation with different metal ions in ethanol.Bithpy and Mn(II)synthesize Mn(bithpy-2)Cl₂·2DMF complex in DMF solution.It is worth noting that this complex has obvious photoluminescence properties and a high intensity emission peak(?max=350nm).And the complex shows a bright orange-red emission when it is solid.After further research,we found that the reversible emission intensity change of Mn(bithpy-2)Cl₂·2DMF can be applied to the qualitative heterogeneous solid-vapor switch of DMF solvents.Compared with ligands,manganese complexes have higher thermal stability(up to 500?).Analysis and spectroscopic studies have shown that the composition of the complex conforms to the general formula,[MLX2]·n H2O,(M=Mn,Co,Ni,Cu;X=Cl;n are(4,6,6,2)respectively.By single crystal x-ray diffraction,ultraviolet absorption,fluorescence emission,thermogravimetric analysis(TGA),X-ray powder diffraction(XRD)and others have characterized the manganese complex.The Heck coupling reaction was used as a representative to investigate the catalytic activity of Pd-Bithpy.In exploring the catalytic reaction,the optimal conditions were 2 mol%catalyst,KOH was the base,DMF was the solvent,and the reaction was performed at 120?for 5 hours.The catalyst can catalyze various substituents on aryl halides and styrene derivatives,and the yield from aryl iodo compound to aryl chloro compound is from high to moderate.At the same time,we compared its catalytic activity with a series of pyridine-containing ligands such as 1,10-phenanthroline and 2,2-bipyridine and palladium complexes.The activity is attributed to the electron-rich structure.Adding CO₂ to epoxy compounds is the"green"way to produce cyclic carbonates.We synthesized a series of new triazine materials(CTFs)by trimerization and characterized them by Fourier transform infrared spectroscopy,X-ray powder diffraction,thermogravimetric analysis,and transmission electron microscopy.The material has a porous structure,high nitrogen content,and good thermal stability.Under the conditions of no metal,no solvent and no cocatalyst,our group systematically investigated the optimal reaction time,reaction temperature,CO₂ pressure and catalyst dosage of ICB-CTF-400 for catalyzing the conversion of CO2 to cyclic carbonate.Under the optimal conditions,the scope of substrates of the catalytic system is extended.In addition,the catalyst can be reused at least 5 times without significant reduction in catalytic activity.This new CTFs material can be used as a more environmentally friendly catalyst to prepare cyclic carbonates by chemically fixing CO₂.