Crown Ethers And COF Of Synthesis And Catalysis Based N-Heterocyclic Carbene

Transition metals catalyzed various coupling reactions play a very important role in organic synthesis and are one of the most effective means of forming C-C bonds and C-N bonds.They have been widely used in kinds of fields in organic synthesis chemistry.In recent years,studies about coupling reactions have emerged common.In this paper,we mainly constructing a new catalytic system to introduct the coupling reaction of aryl iodide and organobismuth reagents at room temperature.Meanwhile,a novel N-Heterocyclic carbene based on COF material was synthesized by high-pressure reactor and it as a new catalyst has been applied in the Suzuki-Miyaura coupling reaction.We have developed the N-Heterocyclic carbene ligand/PdCl₂ catalyst for C-C coupling reaction of aryl iodides and organobismuths at room temperature.The established catalytic system exhibited high cross-coupling reactivity between a variety of orgnobismuths and aryl iodides in the presence of K₂CO₃ as base in NMP or DMSO at room temperature.The simple and efficient transformation can tolerate either electron-withdrawing or electron-donating functional groups.It was notably found that both aryl bromide and aryl chloride generated moderate to good yields of the corresponding biphenyl products using 5 mol%of PPh₃/ligand5?1:1?as catalyst.In this thesis,the N-Heterocyclic carbene-COF material was characterized by FT-IR,NMR,XRD,UV,TGA,SEM and TEM.It provides a high potential for catalytic reactions due to its regularity in structure.The results show that it has an excently activity in the Suzuki-Miyaura coupling reaction of aryl halide and phenylboronic acid at room temperature.