New Strategies Of Copper-catalyzed Ullmann Reaction

The copper catalyzed Ullmann coupling reaction is one of the most importantmethods to synthesize arylamines, diaryl ethers or sulfur ethers. Our work is to developmild procedures to synthesize these compounds by using new strategies. In this thesis,we described following four parts of work.1. Ligand-free Cu（OAc）₂·H₂O-catalyzed N-arylation of nitrogen-containingheterocycles. We researched the Ullmann C-N coupling reactions catalyzed by Cu（I）pyrazolate polymeric complexes got by the hydrothermal reaction of pyrazoles withCu（II） salts. In the absence of any additional ligands, the Cu（OAc）₂·H₂O-catalyzedUllmann C-N coupling reactions of nitrogen-containing heterocycles with aryl iodidescould be performed at110oC to give the corresponding products in high yields. Thecatalyst loading is the least compared with those of the previous reports.2. Schiff-base promoted copper-catalyzed Ullmann C-N, C-S, C-O couplingreations. Using the ligand isobutylidene-pyridin-2-yl-amine as the promoter, theCuI-catalyzed coupling reactions of aryl halides with N-containing heterocycles,thiophenol,2-pyridinethiol or phenol could be carried out at100oC to afford productsin high yields.3. CuCN-catalyzed Ullmann C-N coupling reaction of nitrogen-containingheterocycles with aryl boronic acids. Under O2, the CuCN-catalyzed Ullmann C-Ncoupling reactions of pyrazole or imidazole with aryl boronic acids could be performedto give the corresponding products. This protocol using water as solvent without addingany base is environmentally friendly.4. Synthesis and characterization of Cu（I） pyrazolate polymeric complexes. Threecomplexes [Cu（pz）]_n（1）,[Cu₃（μ-pz）₄K（18-Crown-6）]_n（2） and[{（（Phen）Cu）₂（μ-CN）₂}{Cu₂（pz）2}]_n（3） were got by the hydrothermal reactions. Complexes1-3were characterized by elemental analysis, infrared spectrum. Structuresof1-3were characterized by X-ray diffraction crystallography. The luminescenceproperties of1-3were also investigated.