Novel acyclic Pd（II）-N-heterocyclic carbene （NHC） metallacrown ethers 5a, 5b have been synthesized. Reaction of the imidazolium salts hearing a long polyether chain with Ag2O afforded Ag-NHC complexes, which then ...Novel acyclic Pd（II）-N-heterocyclic carbene （NHC） metallacrown ethers 5a, 5b have been synthesized. Reaction of the imidazolium salts hearing a long polyether chain with Ag2O afforded Ag-NHC complexes, which then reacted as carbene transfer agent with PdCl2（MeCN）2 to give the desired acyelic Pd（Ⅱ）-NHC metallacrown ether complexes 5a and 5b. The 1H NMR and 13C NMR spectra show fia and fib exist as mixtures ofcis and trans isomers in solution. The trans isomer of 5a was characterized by X-ray diffraction, which clearly demonstrated two pseudo-crown ether cavities in trans-5a. Pd（Ⅱ）-NHC complexes 5a and 5b have been shown to be highly effective in the Suzuki-Miyaura reactions of a variety of aryl bromides in neat water without the need of inert gas protection.展开更多
Reactions of copper（Ⅱ） sulfate or copper（Ⅱ） perchlorate,samarium（Ⅲ）,erbium（Ⅲ） or neodymium（Ⅲ）nitrate（5/1 equiv.） with pyrazinohydroxamic acid（H2Pyzha） in H2O/Me0 H led to three new heterobimetallic ...Reactions of copper（Ⅱ） sulfate or copper（Ⅱ） perchlorate,samarium（Ⅲ）,erbium（Ⅲ） or neodymium（Ⅲ）nitrate（5/1 equiv.） with pyrazinohydroxamic acid（H2Pyzha） in H2O/Me0 H led to three new heterobimetallic 15-metallacrown-5 complexes.In a MeOH/H2O solution,when adding inorganic salts,the ligands exist as protonated metallacrowns.In the solid state,their structures are more complicated as confirmed by X-ray analysis：metallacrown[Sm（H2O）3 {Cu（pyzha）}5（H2O）2（MeOH）（HSO4）2]·（H2O）2（HSO4）（1）;[Nd（H2O）2（MeOH） {Cu（pyzha）}5（ClO4）2（H2O）5（NO3）]（2）;[Eu（H2O）2（MeOH） {Cu（pyzha）}5（ClO4）2（H2O）5（NO3）]（3）.The differentiation of atomic and ionic radii between the encapsulated lanthanide（Ⅲ） could be used to control the bowl-shape distortion of the metallacrowns from the planar geometry.The complex 1 clearly exhibits fluorescence behavior of samarium（Ⅲ）,while 2and 3 show that of copper（Ⅱ） and ligand.展开更多
Same new phosphorus donors containing trans-Fe(0) metallacrown ethers were obtained by template synthesis. The co-catalytic properties of these complexes and the X-ray diffraction structure of complex 1 were discussed.
基金Supporting information for this article is available on the WWW under http：//dx.doi.org/10.1002/cjoc.201100596 or from the author.Acknowledgement This work was supported by the Natural Science Foundation of China （Nos. 21021001, 21072134） and Program for Changjiang Scholars and Innovative Research Team in University （No. IRT0846）.
文摘Novel acyclic Pd（II）-N-heterocyclic carbene （NHC） metallacrown ethers 5a, 5b have been synthesized. Reaction of the imidazolium salts hearing a long polyether chain with Ag2O afforded Ag-NHC complexes, which then reacted as carbene transfer agent with PdCl2（MeCN）2 to give the desired acyelic Pd（Ⅱ）-NHC metallacrown ether complexes 5a and 5b. The 1H NMR and 13C NMR spectra show fia and fib exist as mixtures ofcis and trans isomers in solution. The trans isomer of 5a was characterized by X-ray diffraction, which clearly demonstrated two pseudo-crown ether cavities in trans-5a. Pd（Ⅱ）-NHC complexes 5a and 5b have been shown to be highly effective in the Suzuki-Miyaura reactions of a variety of aryl bromides in neat water without the need of inert gas protection.
文摘Reactions of copper（Ⅱ） sulfate or copper（Ⅱ） perchlorate,samarium（Ⅲ）,erbium（Ⅲ） or neodymium（Ⅲ）nitrate（5/1 equiv.） with pyrazinohydroxamic acid（H2Pyzha） in H2O/Me0 H led to three new heterobimetallic 15-metallacrown-5 complexes.In a MeOH/H2O solution,when adding inorganic salts,the ligands exist as protonated metallacrowns.In the solid state,their structures are more complicated as confirmed by X-ray analysis：metallacrown[Sm（H2O）3 {Cu（pyzha）}5（H2O）2（MeOH）（HSO4）2]·（H2O）2（HSO4）（1）;[Nd（H2O）2（MeOH） {Cu（pyzha）}5（ClO4）2（H2O）5（NO3）]（2）;[Eu（H2O）2（MeOH） {Cu（pyzha）}5（ClO4）2（H2O）5（NO3）]（3）.The differentiation of atomic and ionic radii between the encapsulated lanthanide（Ⅲ） could be used to control the bowl-shape distortion of the metallacrowns from the planar geometry.The complex 1 clearly exhibits fluorescence behavior of samarium（Ⅲ）,while 2and 3 show that of copper（Ⅱ） and ligand.
基金Project supported by the National Natural Science Foundation of China (No. 29672078)
文摘Same new phosphorus donors containing trans-Fe(0) metallacrown ethers were obtained by template synthesis. The co-catalytic properties of these complexes and the X-ray diffraction structure of complex 1 were discussed.
