Three inexpensive and air-/moisture-stable Salen-Cu complexes 1-3 were evaluated to be a novel class of catalysts for the N-arylation of imidazoles with aryl halides. A variety of aryl iodides, bromides underwent the ...Three inexpensive and air-/moisture-stable Salen-Cu complexes 1-3 were evaluated to be a novel class of catalysts for the N-arylation of imidazoles with aryl halides. A variety of aryl iodides, bromides underwent the coupling with imida-zoles, promoted by the complex 3, in moderate to excellent yields without the protection by an inert gas.展开更多
A novel porphyrin-salen compound and corresponding zinc（Ⅱ） porphyrin-salen compound （ZnPSC10） covalently linked by a flexible alkoxy chain （-O（CH）10O--） have been synthesized and characterized. Molecular reco...A novel porphyrin-salen compound and corresponding zinc（Ⅱ） porphyrin-salen compound （ZnPSC10） covalently linked by a flexible alkoxy chain （-O（CH）10O--） have been synthesized and characterized. Molecular recognition of three N-heterocyclic guests, pyridine, 1,4-diazobycyclo[2,2,2]octane （DABCO） and pyrazine, with the host ZnPSC10 was investigated. Binding constants were determined by means of UV-vis titration method. The binding mode of ZnPSC10 with DABCO has been discussed in detail by using ^1H NMR. It was found that the conformations of the recognition system changed from closed to open with the adding of DABCO.展开更多
A variety of unique Al(salen) complexes functionalized by imidazolium-based ionic liquid(IL) moieties with the salen ligand at the two sides of 3,3′-position have been successfully prepared, rather than familiar 5,5...A variety of unique Al(salen) complexes functionalized by imidazolium-based ionic liquid(IL) moieties with the salen ligand at the two sides of 3,3′-position have been successfully prepared, rather than familiar 5,5′-position reported previously.The catalytic activity obtained by these bifunctional catalysts could be superior to those of the binary type catalysts in the formation of five-membered heterocyclic compounds from the cycloaddition reaction of CO_2 and three-membered heterocyclic compounds(including terminal epoxides and N-substituted aziridines), presumably due to the distinguished intramolecularly synergistic catalysis, which might lead to perform the cycloaddition reaction at ambient conditions and retain excellent yield and unprecedented chemo-or regioselectivity. Moreover, the polyether-based trifunctional Al(salen) catalysts with the best catalytic performance could be regenerated and reused at least eight times without any obvious decreases in catalytic activity. Finally,the kinetic investigation suggested the structure of catalysts had important influences on the catalytic activity, thereby proposing the possible reaction mechanism.展开更多
文摘Three inexpensive and air-/moisture-stable Salen-Cu complexes 1-3 were evaluated to be a novel class of catalysts for the N-arylation of imidazoles with aryl halides. A variety of aryl iodides, bromides underwent the coupling with imida-zoles, promoted by the complex 3, in moderate to excellent yields without the protection by an inert gas.
基金Project supported by the National Natural Science Foundation of China （Nos. 20271030, 20303009） and the Key Laboratory of 0pto-Electronics Information Science and Technology of Ministry of Education.
文摘A novel porphyrin-salen compound and corresponding zinc（Ⅱ） porphyrin-salen compound （ZnPSC10） covalently linked by a flexible alkoxy chain （-O（CH）10O--） have been synthesized and characterized. Molecular recognition of three N-heterocyclic guests, pyridine, 1,4-diazobycyclo[2,2,2]octane （DABCO） and pyrazine, with the host ZnPSC10 was investigated. Binding constants were determined by means of UV-vis titration method. The binding mode of ZnPSC10 with DABCO has been discussed in detail by using ^1H NMR. It was found that the conformations of the recognition system changed from closed to open with the adding of DABCO.
基金supported by the National Science for Distinguished Young Scholars of China(21425627)the National Natural Science Foundation of China(21676306)+1 种基金the Natural Science Foundation of Guangdong Province(2016A030310211,2015A030313104)the Fundamental Research Funds for the Central Universities of Sun Yat-sen University
文摘A variety of unique Al(salen) complexes functionalized by imidazolium-based ionic liquid(IL) moieties with the salen ligand at the two sides of 3,3′-position have been successfully prepared, rather than familiar 5,5′-position reported previously.The catalytic activity obtained by these bifunctional catalysts could be superior to those of the binary type catalysts in the formation of five-membered heterocyclic compounds from the cycloaddition reaction of CO_2 and three-membered heterocyclic compounds(including terminal epoxides and N-substituted aziridines), presumably due to the distinguished intramolecularly synergistic catalysis, which might lead to perform the cycloaddition reaction at ambient conditions and retain excellent yield and unprecedented chemo-or regioselectivity. Moreover, the polyether-based trifunctional Al(salen) catalysts with the best catalytic performance could be regenerated and reused at least eight times without any obvious decreases in catalytic activity. Finally,the kinetic investigation suggested the structure of catalysts had important influences on the catalytic activity, thereby proposing the possible reaction mechanism.
