Cu2O and Cul were supported on multiwalled carbon nanotubes （MWCNTs） using a wet impregna- tion method, and the resulting materials were fully characterized by powder X-ray diffraction, Fourier transform infrared sp...Cu2O and Cul were supported on multiwalled carbon nanotubes （MWCNTs） using a wet impregna- tion method, and the resulting materials were fully characterized by powder X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy with energy dispersive X-ray spectroscopy, transmission electron microscopy, and temperature-programmed desorption with ammonia analysis. The results of these experiments revealed that Cu2O and CuI were deposited on the MWCNTs in the cubic and γ phases, respectively. These results also showed that the Cu-containing MWCNTs exhibited weak to strong electron-accepting （Lewis acidic） properties. The catalytic activities of these materials were studied for the synthesis of biologically significant N-（pyridin-2-yl）benzamides via the oxidative amidation of aryl aldehydes with 2-aminopyridines. The yields of the products were in the range 50%-95% with 100% selectivity. Notably, the CuI/MWCNT catalyst was much more effective than the Cu2O/MWCNT catalyst with respect to the isolated yield of the product, although the latter of these two catalysts exhibited much better recyclability. A preferential interaction was observed between the polar nature of the acid-activated MWCNTs and the ionic Cu2O compared with covalent CuL The differences in these interactions had a significant impact on the rate of the nucleophilic attack of the amino group of 2-aminopyridine substrate on the carbonyl group of the aryl aldehyde.展开更多
The complex Mn(apo)6Cl2 (apo=2-aminopyridine N-oxide) was obtained by the reaction of MnCl2(4H2O with apo(HCl and NaOH in ethanol. A single-crystal X-ray study shows that the complex is mononuclear with octahedral coo...The complex Mn(apo)6Cl2 (apo=2-aminopyridine N-oxide) was obtained by the reaction of MnCl2(4H2O with apo(HCl and NaOH in ethanol. A single-crystal X-ray study shows that the complex is mononuclear with octahedral coordination environment (MnC30H36N12O6Cl2). The oxygen atoms from apo ligands coordinate to the manganese atom forming Mn(apo)6Cl2. The compound Mn(apo)6Cl2 is hexagonally symmetric with space group R3, lattice constants: a = 12.010(2), b = 12.010(2), c = 20.232(4) ?, ( = 120(, V= 2527.4(7) ?3, Z=3, Mr =786.55, Dc=1.550 g/cm3, (= 0.614mm-1, F(000) = 1221, R = 0.0541, Rw = 0.0580 for 1229 reflections with I>2((I). The distances between Mn(II) and O atoms are in the range from 2.171(5) to 2.184(5) ?, and the distance between the chlorine anion and N atom of amido group is 3.3 ?. The dihedral angle between two adjacent pyridine ring planes is 59.19 (0.17)°.展开更多
A mixed complex [Zn（C5H6N2）（HL）2] （C5H6N2 = 2-aminopyridine, H2L = acetylacetone） has been synthesized and characterized by IR, elemental analysis and X-ray single-crystal diffraction analysis. The crystal belon...A mixed complex [Zn（C5H6N2）（HL）2] （C5H6N2 = 2-aminopyridine, H2L = acetylacetone） has been synthesized and characterized by IR, elemental analysis and X-ray single-crystal diffraction analysis. The crystal belongs to monoclinic, space group P21/c with a = 7.4490（15）, b = 8.2650（17）, c = 27.615（6） A°, β= 101.69（3）°, V = 1664.9（6）A°^3, Z = 4, Mr = 357.70, Dc = 1.427 g/cm^3, F（000） = 744, μ = 1.493 mm^-1, R = 0.0309 and wR = 0.0771. The Zn（Ⅱ） is coordinated by one nitrogen atom from 2-aminopyridine and four oxygen atoms from two acetylacetone anions to furnish a distorted square pyramid geometry. The complex forms a three-dimensional network through intermolecular hydrogen bonds.展开更多
The complex [Cu2（apo）4Cl4]·2H2O （apo=2-aminopyridine N-oxide） was obtained. A single- crystal X-ray study shows that the complex is a binuclear compound （Cu2C20H28Cl4N8O6）. The coordination geometry about e...The complex [Cu2（apo）4Cl4]·2H2O （apo=2-aminopyridine N-oxide） was obtained. A single- crystal X-ray study shows that the complex is a binuclear compound （Cu2C20H28Cl4N8O6）. The coordination geometry about each copper atom is best described as a distorted square pyramid. The compound [Cu2（apo）4Cl4]·2H2O belongs to the triclinic system with space group P, lattice constants: a = 7.8550（7）, b = 8.5378（7）, c = 12.082（1） ?, α = 72.807（1）, β = 77.641（1）, γ = 70.800（1）(, V =724.85（11） ?3, Z=1, Mr =745.38, Dc=1.708 g/cm3, μ =1.886mm-1, F（000） =378, R=0.0359, wR2=0.0884 for 2220 reflections with I >2σ（I）. The distances between Cu（II） and O atoms are in the range from 1.934（2） to 2.042（2）?. The distance between two copper atoms Cu-Cu（A） is 3.2978（8） ?. The distances of Cu-Cl（1） and Cu-Cl（2） are 2.2322（9）, 2.5095（10） ?, respectively. There is no evident hydrogen bond between N and Cl.展开更多
A palladium catalyst supported on 2-amino- pyridine functionalized cellulose was synthesized and fully characterized by inductively coupled plasma atomic emission spectroscopy, transmission electron microscope, Fourie...A palladium catalyst supported on 2-amino- pyridine functionalized cellulose was synthesized and fully characterized by inductively coupled plasma atomic emission spectroscopy, transmission electron microscope, Fourier transform infrared spectroscopy, thermogravi- metric analysis and X-ray photoelectron spectrometry. This catalyst can be applied in the Suzuki cross-coupling reaction of aryl halides with arylboronic acids in 50% ethanol to afford biaryls in good yields, and easily recycled by simple filtration after reaction without the loss of metal Pd.展开更多
基金DST-SERB for the financial support for this research work(Project number:SERB/F/3690/2013-14)
文摘Cu2O and Cul were supported on multiwalled carbon nanotubes （MWCNTs） using a wet impregna- tion method, and the resulting materials were fully characterized by powder X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy with energy dispersive X-ray spectroscopy, transmission electron microscopy, and temperature-programmed desorption with ammonia analysis. The results of these experiments revealed that Cu2O and CuI were deposited on the MWCNTs in the cubic and γ phases, respectively. These results also showed that the Cu-containing MWCNTs exhibited weak to strong electron-accepting （Lewis acidic） properties. The catalytic activities of these materials were studied for the synthesis of biologically significant N-（pyridin-2-yl）benzamides via the oxidative amidation of aryl aldehydes with 2-aminopyridines. The yields of the products were in the range 50%-95% with 100% selectivity. Notably, the CuI/MWCNT catalyst was much more effective than the Cu2O/MWCNT catalyst with respect to the isolated yield of the product, although the latter of these two catalysts exhibited much better recyclability. A preferential interaction was observed between the polar nature of the acid-activated MWCNTs and the ionic Cu2O compared with covalent CuL The differences in these interactions had a significant impact on the rate of the nucleophilic attack of the amino group of 2-aminopyridine substrate on the carbonyl group of the aryl aldehyde.
文摘The complex Mn(apo)6Cl2 (apo=2-aminopyridine N-oxide) was obtained by the reaction of MnCl2(4H2O with apo(HCl and NaOH in ethanol. A single-crystal X-ray study shows that the complex is mononuclear with octahedral coordination environment (MnC30H36N12O6Cl2). The oxygen atoms from apo ligands coordinate to the manganese atom forming Mn(apo)6Cl2. The compound Mn(apo)6Cl2 is hexagonally symmetric with space group R3, lattice constants: a = 12.010(2), b = 12.010(2), c = 20.232(4) ?, ( = 120(, V= 2527.4(7) ?3, Z=3, Mr =786.55, Dc=1.550 g/cm3, (= 0.614mm-1, F(000) = 1221, R = 0.0541, Rw = 0.0580 for 1229 reflections with I>2((I). The distances between Mn(II) and O atoms are in the range from 2.171(5) to 2.184(5) ?, and the distance between the chlorine anion and N atom of amido group is 3.3 ?. The dihedral angle between two adjacent pyridine ring planes is 59.19 (0.17)°.
基金This work was supported by Qingdao Science and Technology Plan Items (03-3-nsh-28)
文摘A mixed complex [Zn（C5H6N2）（HL）2] （C5H6N2 = 2-aminopyridine, H2L = acetylacetone） has been synthesized and characterized by IR, elemental analysis and X-ray single-crystal diffraction analysis. The crystal belongs to monoclinic, space group P21/c with a = 7.4490（15）, b = 8.2650（17）, c = 27.615（6） A°, β= 101.69（3）°, V = 1664.9（6）A°^3, Z = 4, Mr = 357.70, Dc = 1.427 g/cm^3, F（000） = 744, μ = 1.493 mm^-1, R = 0.0309 and wR = 0.0771. The Zn（Ⅱ） is coordinated by one nitrogen atom from 2-aminopyridine and four oxygen atoms from two acetylacetone anions to furnish a distorted square pyramid geometry. The complex forms a three-dimensional network through intermolecular hydrogen bonds.
文摘The complex [Cu2（apo）4Cl4]·2H2O （apo=2-aminopyridine N-oxide） was obtained. A single- crystal X-ray study shows that the complex is a binuclear compound （Cu2C20H28Cl4N8O6）. The coordination geometry about each copper atom is best described as a distorted square pyramid. The compound [Cu2（apo）4Cl4]·2H2O belongs to the triclinic system with space group P, lattice constants: a = 7.8550（7）, b = 8.5378（7）, c = 12.082（1） ?, α = 72.807（1）, β = 77.641（1）, γ = 70.800（1）(, V =724.85（11） ?3, Z=1, Mr =745.38, Dc=1.708 g/cm3, μ =1.886mm-1, F（000） =378, R=0.0359, wR2=0.0884 for 2220 reflections with I >2σ（I）. The distances between Cu（II） and O atoms are in the range from 1.934（2） to 2.042（2）?. The distance between two copper atoms Cu-Cu（A） is 3.2978（8） ?. The distances of Cu-Cl（1） and Cu-Cl（2） are 2.2322（9）, 2.5095（10） ?, respectively. There is no evident hydrogen bond between N and Cl.
基金Acknowledgements This work was supported by National Natural Science Foundation of China （Grant No. 20972109） and National Youth Science Foundation of China （No. 51403151）.
文摘A palladium catalyst supported on 2-amino- pyridine functionalized cellulose was synthesized and fully characterized by inductively coupled plasma atomic emission spectroscopy, transmission electron microscope, Fourier transform infrared spectroscopy, thermogravi- metric analysis and X-ray photoelectron spectrometry. This catalyst can be applied in the Suzuki cross-coupling reaction of aryl halides with arylboronic acids in 50% ethanol to afford biaryls in good yields, and easily recycled by simple filtration after reaction without the loss of metal Pd.
