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
目的:建立HPLC法测定甲苯磺酸索拉非尼中的有关物质。方法:色谱柱为C18柱(250 mm×4.6mm,5μm),流动相A为pH2.4磷酸盐缓冲液(取磷酸二氢钾0.790 8 g,置1 000 m L水中,摇匀,用磷酸调节p H 2.4)-乙腈-乙醇(90∶6∶4),流动相B为p H 2....目的:建立HPLC法测定甲苯磺酸索拉非尼中的有关物质。方法:色谱柱为C18柱(250 mm×4.6mm,5μm),流动相A为pH2.4磷酸盐缓冲液(取磷酸二氢钾0.790 8 g,置1 000 m L水中,摇匀,用磷酸调节p H 2.4)-乙腈-乙醇(90∶6∶4),流动相B为p H 2.4磷酸盐缓冲液-乙腈-乙醇(20∶48∶32),进行梯度洗脱,流速为1.0 m L·min^(-1),柱温为35℃,检测波长为235 nm。结果:索拉非尼与各已知杂质及强制破坏产生的降解产物均分离度良好,PAPE-氨基甲酸乙酯、CTF-苯胺、CTF-氨基甲酸乙酯、4-(4-氨基苯氧基)-N-甲基吡啶-2-甲酰胺质量浓度分别在0.567 0~5.670 2μg·、0.569 1~5.691 0μg·m L^(-1)、0.573 5~5.734 8μg·、0.556 4~5.564 4μg·范围内与峰面积呈良好的线性关系,校正因子分别为3.2、1.1、1.6、2.1;定量下限分别为0.06、0.17、0.14、0.06μg·m L^(-1);回收率分别为99.5%、96.7%、99.3%、93.3%,RSD依次为0.69%、0.98%、0.65%、1.9%(n=9)。3批样品有关物质测定结果显示,已知杂质和未知杂质含量均低于0.10%。结论:该方法可用于甲苯磺酸索拉非尼有关物质的测定。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.
