Iminodiacetic acid resin-chelated copper(Ⅱ) complex is effective in cross-coupling reactions between azaheterocycles and aryl or heteroaryl halides,providing N-arylated products in good to excellent yields.The copper...Iminodiacetic acid resin-chelated copper(Ⅱ) complex is effective in cross-coupling reactions between azaheterocycles and aryl or heteroaryl halides,providing N-arylated products in good to excellent yields.The copper catalyst is air stable and can be readily recovered and reused with minimal loss of activity for three runs.展开更多
Four inexpensive and air-/moisture-stable pyrrolecarbaldiminato-Cu complexes 1-4 were synthesized and evaluated to be a novel class of catalysts for the N-arylation of imidazoles with aryl halides. A variety of aryl i...Four inexpensive and air-/moisture-stable pyrrolecarbaldiminato-Cu complexes 1-4 were synthesized and evaluated to be a novel class of catalysts for the N-arylation of imidazoles with aryl halides. A variety of aryl iodides, bromides and activated aryl chlorides underwent the coupling with imidazoles, promoted by the catalyst 4, in moderate to good yields without the protection by an inert gas.展开更多
Tetrazole-l-acetic acid was found to serve as a superior ligand for Cul-catalyzed N-arylation of imidazoles with aryl iodides under a low catalyst loading (5 mol% of Cul). A variety of aryl iodides could he aminated...Tetrazole-l-acetic acid was found to serve as a superior ligand for Cul-catalyzed N-arylation of imidazoles with aryl iodides under a low catalyst loading (5 mol% of Cul). A variety of aryl iodides could he aminated to provide the N-arylated products in good to excellent yields without the need of an inert atmosphere.展开更多
N-Arylation of a wide variety of amines with phenylboronic acid catalyzed by copper acetate under 20%aqueous solution of n-Bu_4NOH was accomplished in good to excellent yields(up to 92%) and substrate conversions(u...N-Arylation of a wide variety of amines with phenylboronic acid catalyzed by copper acetate under 20%aqueous solution of n-Bu_4NOH was accomplished in good to excellent yields(up to 92%) and substrate conversions(up to 96%).展开更多
Herein,we report rhodium catalyzed N-arylation via addition of arylboronic acids to electron-deficientα-iminoesters which can be prepared in high efficiency by using easily accessible B-carbonyl esters.The reaction i...Herein,we report rhodium catalyzed N-arylation via addition of arylboronic acids to electron-deficientα-iminoesters which can be prepared in high efficiency by using easily accessible B-carbonyl esters.The reaction is highly regiospecific to achieve the N-aryl addition efficiently with up to 99%yield under mild conditions.The corresponding product can be further efficiently converted into indoles andaseries of other important building blocks.展开更多
A general and efficient Cu(II)-catalyzed cross-coupling method is reported for the preparation of acyclic tertiary amides. Generally moderate to excellent yields and functional group tolerance were obtained with sec...A general and efficient Cu(II)-catalyzed cross-coupling method is reported for the preparation of acyclic tertiary amides. Generally moderate to excellent yields and functional group tolerance were obtained with secondary acyclic amides and aryl halides as substrates in toluene.展开更多
10 mol% Cul combined with the DMEDA ligand can efficiently catalyze the N-arylation of 2-arylindoles with aryl iodides and aryl bromides in good to excellent yields. The aryl halides bearing electron-rich or electron-...10 mol% Cul combined with the DMEDA ligand can efficiently catalyze the N-arylation of 2-arylindoles with aryl iodides and aryl bromides in good to excellent yields. The aryl halides bearing electron-rich or electron-deficient functional groups can be well tolerated under this mild reaction conditions.展开更多
Two new Cu(Ⅰ) complexes [CuCl(3-PyOH)(PPh_3)_2](1) and [Cu_2(μ-Cl)_2(4-Stpy)(Ph_3P)_3](2)(PyOH = hydroxypyridine; stpy = styrylpyridine) with triphenylphosphine and pyridine derivatives have been s...Two new Cu(Ⅰ) complexes [CuCl(3-PyOH)(PPh_3)_2](1) and [Cu_2(μ-Cl)_2(4-Stpy)(Ph_3P)_3](2)(PyOH = hydroxypyridine; stpy = styrylpyridine) with triphenylphosphine and pyridine derivatives have been synthesized and characterized by elemental analysis and X-ray single-crystal diffraction. Compound 1 crystallizes in monoclinic, space group P2_1/c with a = 9.8945(7), b = 37.266(2), c = 10.9461(7) A, β = 116.0750(10)°, V = 3625.3(4) A^3, Z = 4, D_c = 1.350 Mg/cm^(-3), μ = 0.801 mm^(-1), F(000) = 1528, the final R = 0.0320 and w R = 0.0729 for 18568 observed reflections(I 〉 2σ(I)), R(all data) = 0.0413, wR(all data) = 0.0769, completeness to theta of 25.01 is 99.9% and GOF = 1.037. Compound 2 crystallizes in monoclinic, space group P2_1/c with a = 11.290(3), b = 20.388(5), c = 24.092(6) A, β = 102.028(4)°, V = 5424(2) A^3, Z = 4, D_c = 1.428 Mg/cm^(-3), μ = 1.016 mm^(-1), F(000) = 2408, the final R = 0.0568 and w R = 0.1486 for 27644 observed reflections(I 〉 2σ(I)), R(all data) = 0.0716, wR(all data) = 0.1592, completeness to theta of 25.01 is 99.9% and GOF = 1.056. Two new Cu(I) complexes have been utilized as catalysts for N-arylation of imidazole and both showed good catalytic activity.展开更多
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
Ma's CuI/proline procedure for the catalytic cross coupling between nitrogen heterocycles and aryl halides was markedly improved. The key finding was that K3PO4 was a much better base than K2CO3 for the reaction. Wit...Ma's CuI/proline procedure for the catalytic cross coupling between nitrogen heterocycles and aryl halides was markedly improved. The key finding was that K3PO4 was a much better base than K2CO3 for the reaction. With this new reaction condition the cross coupling with aryl iodides could be accomplished in 1,4-dioxane instead of DMSO. This reactin also could be carried out in DMF. Furthermore, the coupling yields under the new conditions are usually higher than in Ma's original methods.展开更多
A novel strategy to synthesize copper-based nanoparticles supported on carbon nitride(C3 N4) was developed by popping of mixture containing C3 N4 and cupric nitrate. Characterizations such as X-ray photoelectron spect...A novel strategy to synthesize copper-based nanoparticles supported on carbon nitride(C3 N4) was developed by popping of mixture containing C3 N4 and cupric nitrate. Characterizations such as X-ray photoelectron spectroscopy(XPS) and X-ray diffraction(XRD) indicate that the structure of g-C3 N4 maintained although a popping process occurred. High resolution transmission electronic microscopy(HRTEM) characterization illustrated that copper-based nanoparticles with diameter of < 1 nm were well distributed on g-C3 N4. This kind of copper catalyst exhibits high catalytic activity and selectivity in arylation of pyrazole, a simple and effect strategy to construct C-N bond in organic chemistry.According to the results of control experiments and characterizations, cuprous oxide should be the catalytic active phase in the supported coperbased catalyst.展开更多
Bifunctional Salen-Cu(II) complex catalyzed cross-coupling reactions of aryl halids with imidazoles or phenylboronic acid reagents have been developed as practical methods for C--N and C--C bond formation. The proce...Bifunctional Salen-Cu(II) complex catalyzed cross-coupling reactions of aryl halids with imidazoles or phenylboronic acid reagents have been developed as practical methods for C--N and C--C bond formation. The procedure tolerates aryl halides with various functional groups(such as methoxy, acetyl, nitrile, fluoro and nitro groups) and gives the corresponding coupling products in moderate to high yields. The catalyst remained active after fiye successive catalytic runs without loss in performance.展开更多
Carbon-supported copper catalyst was prepared for the first time in one-step with copper nitrate and corn stalk through calcination under different temperatures. Uniformly dispersed nanoparticles were obtained and wer...Carbon-supported copper catalyst was prepared for the first time in one-step with copper nitrate and corn stalk through calcination under different temperatures. Uniformly dispersed nanoparticles were obtained and were identified to be Cu(0) and Cu(Ⅰ) in XRD patterns. Excellent catalytic activity and selectivity were achieved in the N-arylation of pyrazole under ligand and protection gas free conditions. About90.4% of product yield was achieved with only 0.5 mol% of copper catalyst(Cu-C-300), which was considerably more efficient than previous reports. XPS results suggested that the N-arylation of pyrazole activity was closely related to the surface Cu(Ⅰ) species.展开更多
基金supported by the Natural Science Foundation of Zhejiang Province(No.Y407240).
文摘Iminodiacetic acid resin-chelated copper(Ⅱ) complex is effective in cross-coupling reactions between azaheterocycles and aryl or heteroaryl halides,providing N-arylated products in good to excellent yields.The copper catalyst is air stable and can be readily recovered and reused with minimal loss of activity for three runs.
文摘Four inexpensive and air-/moisture-stable pyrrolecarbaldiminato-Cu complexes 1-4 were synthesized and evaluated to be a novel class of catalysts for the N-arylation of imidazoles with aryl halides. A variety of aryl iodides, bromides and activated aryl chlorides underwent the coupling with imidazoles, promoted by the catalyst 4, in moderate to good yields without the protection by an inert gas.
基金supported fnancially by the National Basic Research Program of China(973 Program,No.2012CB722603)the Start-Up Foundation for Young Scientists of Shihezi University(Nos.RCZX201012,RCZX201014,RCZX201015)
文摘Tetrazole-l-acetic acid was found to serve as a superior ligand for Cul-catalyzed N-arylation of imidazoles with aryl iodides under a low catalyst loading (5 mol% of Cul). A variety of aryl iodides could he aminated to provide the N-arylated products in good to excellent yields without the need of an inert atmosphere.
文摘N-Arylation of a wide variety of amines with phenylboronic acid catalyzed by copper acetate under 20%aqueous solution of n-Bu_4NOH was accomplished in good to excellent yields(up to 92%) and substrate conversions(up to 96%).
基金financial support from the Natural Science Foundation of Shanghai(20zR1405500).
文摘Herein,we report rhodium catalyzed N-arylation via addition of arylboronic acids to electron-deficientα-iminoesters which can be prepared in high efficiency by using easily accessible B-carbonyl esters.The reaction is highly regiospecific to achieve the N-aryl addition efficiently with up to 99%yield under mild conditions.The corresponding product can be further efficiently converted into indoles andaseries of other important building blocks.
基金We gratefully thank the National Natural Science Foundation of China (No. 31071720) for generous fi- nancial support.
文摘A general and efficient Cu(II)-catalyzed cross-coupling method is reported for the preparation of acyclic tertiary amides. Generally moderate to excellent yields and functional group tolerance were obtained with secondary acyclic amides and aryl halides as substrates in toluene.
基金supported by the National Natural Science Foundation of China (No.21102036)Plan for Scientific Innovation Talent of Henan University of Technology (No.11CXRC02)startup fund from HAUT (No.2010BS042)
文摘10 mol% Cul combined with the DMEDA ligand can efficiently catalyze the N-arylation of 2-arylindoles with aryl iodides and aryl bromides in good to excellent yields. The aryl halides bearing electron-rich or electron-deficient functional groups can be well tolerated under this mild reaction conditions.
基金Supported by the National Natural Science Foundation of China(NSFC 21102102)
文摘Two new Cu(Ⅰ) complexes [CuCl(3-PyOH)(PPh_3)_2](1) and [Cu_2(μ-Cl)_2(4-Stpy)(Ph_3P)_3](2)(PyOH = hydroxypyridine; stpy = styrylpyridine) with triphenylphosphine and pyridine derivatives have been synthesized and characterized by elemental analysis and X-ray single-crystal diffraction. Compound 1 crystallizes in monoclinic, space group P2_1/c with a = 9.8945(7), b = 37.266(2), c = 10.9461(7) A, β = 116.0750(10)°, V = 3625.3(4) A^3, Z = 4, D_c = 1.350 Mg/cm^(-3), μ = 0.801 mm^(-1), F(000) = 1528, the final R = 0.0320 and w R = 0.0729 for 18568 observed reflections(I 〉 2σ(I)), R(all data) = 0.0413, wR(all data) = 0.0769, completeness to theta of 25.01 is 99.9% and GOF = 1.037. Compound 2 crystallizes in monoclinic, space group P2_1/c with a = 11.290(3), b = 20.388(5), c = 24.092(6) A, β = 102.028(4)°, V = 5424(2) A^3, Z = 4, D_c = 1.428 Mg/cm^(-3), μ = 1.016 mm^(-1), F(000) = 2408, the final R = 0.0568 and w R = 0.1486 for 27644 observed reflections(I 〉 2σ(I)), R(all data) = 0.0716, wR(all data) = 0.1592, completeness to theta of 25.01 is 99.9% and GOF = 1.056. Two new Cu(I) complexes have been utilized as catalysts for N-arylation of imidazole and both showed good catalytic activity.
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.
文摘Ma's CuI/proline procedure for the catalytic cross coupling between nitrogen heterocycles and aryl halides was markedly improved. The key finding was that K3PO4 was a much better base than K2CO3 for the reaction. With this new reaction condition the cross coupling with aryl iodides could be accomplished in 1,4-dioxane instead of DMSO. This reactin also could be carried out in DMF. Furthermore, the coupling yields under the new conditions are usually higher than in Ma's original methods.
基金supported the following funders: One Hundred Talent Project of Hebei Province (Grant No. E2016100015)National Natural Science Foundation of China (No. 21773053)+2 种基金Hebei provincial Natural Science Foundation (No. B2017201084)Hebei Provincial Technology Foundation for High-level talents (No. CL201601)the science technology research and development guidance program project of Baoding City (No. 16ZF027)
文摘A novel strategy to synthesize copper-based nanoparticles supported on carbon nitride(C3 N4) was developed by popping of mixture containing C3 N4 and cupric nitrate. Characterizations such as X-ray photoelectron spectroscopy(XPS) and X-ray diffraction(XRD) indicate that the structure of g-C3 N4 maintained although a popping process occurred. High resolution transmission electronic microscopy(HRTEM) characterization illustrated that copper-based nanoparticles with diameter of < 1 nm were well distributed on g-C3 N4. This kind of copper catalyst exhibits high catalytic activity and selectivity in arylation of pyrazole, a simple and effect strategy to construct C-N bond in organic chemistry.According to the results of control experiments and characterizations, cuprous oxide should be the catalytic active phase in the supported coperbased catalyst.
基金Supported by the National Natural Science Foundation of China(No.20672054) and the Scientific Research Fund of Yunnan Provincial Department of Education, China(No.22012Z020).
文摘Bifunctional Salen-Cu(II) complex catalyzed cross-coupling reactions of aryl halids with imidazoles or phenylboronic acid reagents have been developed as practical methods for C--N and C--C bond formation. The procedure tolerates aryl halides with various functional groups(such as methoxy, acetyl, nitrile, fluoro and nitro groups) and gives the corresponding coupling products in moderate to high yields. The catalyst remained active after fiye successive catalytic runs without loss in performance.
基金supported by the Natural Science Foundation of China(91645115 and 21473003)High-level talents funding project of Hebei(CL201601,E2016100015)science technology research and development guidance program project of Baoding City(No.16ZF027)
文摘Carbon-supported copper catalyst was prepared for the first time in one-step with copper nitrate and corn stalk through calcination under different temperatures. Uniformly dispersed nanoparticles were obtained and were identified to be Cu(0) and Cu(Ⅰ) in XRD patterns. Excellent catalytic activity and selectivity were achieved in the N-arylation of pyrazole under ligand and protection gas free conditions. About90.4% of product yield was achieved with only 0.5 mol% of copper catalyst(Cu-C-300), which was considerably more efficient than previous reports. XPS results suggested that the N-arylation of pyrazole activity was closely related to the surface Cu(Ⅰ) species.