A three-dimensional (3D) Keggin-type heteropolytungstate{Zn(phen)3}3[ZnW12O40]·9H2O 1 (phen = 1,10-phenanthroline) has been synthesized through a conventional hydrothermal synthesis and was characterized by...A three-dimensional (3D) Keggin-type heteropolytungstate{Zn(phen)3}3[ZnW12O40]·9H2O 1 (phen = 1,10-phenanthroline) has been synthesized through a conventional hydrothermal synthesis and was characterized by X-ray single-crystal diffraction analysis, X-ray powder diffraction (XRD), IR, UV-DRS, thermogravimetric analysis (TGA), thermal-dependent 2D-IR correlation spectroscopy (2D-COS IR) and Raman spectrum. Crystal data for compound 1: trigonal system, space group R3 with a = b = 25.268(4), c = 17.462(5) A, ), = 120°, V= 9655(4) A3 and Z = 3. Compound 1 is allomorphic to {Co(phen)3}3[CoW12O40]·9H2O 2, which has been reported by Feng Chai et al. In compound 2, its prominent feature is that the decisive role of water molecules (O-H…O) builds a 3D supramolecular structure. However, in the structure of compound 1, the interlayer space is filled by Zn(phen)3]2+ cations which linked the layers via C-H…O hydrogen bonding interactions to construct a three-dimensional framework. Two compounds are different in weak interactions, so we identify them by Thermal-dependent 2D-COS IR. Moreover, the fluorescence of compound 1 was also described.展开更多
Equilibrium photoproduct of 7r-cyclopentadienyliron dicarbonyl dimer [CpFe(CO)2]2 in non- polar solvent carbon tetrachloride (CC14) is investigated using time-resolved 2D IR spec- troscopy. One of the several poss...Equilibrium photoproduct of 7r-cyclopentadienyliron dicarbonyl dimer [CpFe(CO)2]2 in non- polar solvent carbon tetrachloride (CC14) is investigated using time-resolved 2D IR spec- troscopy. One of the several possible visible-light-driven photoreaction pathways is confirmed and the product is found to contain a di-carbonyl group that exhibits quantum beating be- tween two equivalent transitions in time-resolved 2D IR spectra, which turns out to be the anti-symmetric and symmetric stretching of the terminal carbonyl stretching modes of CpFe(CO)2C1. This is the main product and its reaction pathway involves radical formation, followed by chloride addition. Quantum-chemistry computations support these experimental results. Our results indicate that 2D IR method can be used to identify in situ structures and dynamics of chemical species involved in condensed-phase chemical reactions.展开更多
A new compound {[Bi(trans-DAM)(cis-DAM)(H2O)]NO3·H2O}n 1 derived from bismuth and the flexible ligand N,N'-diacetic acid imidazolium chloride (H2DAMCl) was obtained by hydrothermal synthesis and characte...A new compound {[Bi(trans-DAM)(cis-DAM)(H2O)]NO3·H2O}n 1 derived from bismuth and the flexible ligand N,N'-diacetic acid imidazolium chloride (H2DAMCl) was obtained by hydrothermal synthesis and characterized by single-crystal X-ray diffraction. Compound 1 crystallizes in the monoclinic P21/c space group with a = 9.2298(18), b = 13.339(3), c = 17.090(3) , β = 105.38(2)°, V = 2028.7(7)A^3, Z = 4, C14H18N5O13Bi, Mr = 673.31, Dc = 2.204 g/cm^3, F(000) = 1296, μ = 8.772 mm-1, the final R = 0.0472 and wR = 0.1441 for 4129 observed reflections (I 〉 2σ(I)). In 1, the carboxylic groups from DAM- ligands adopt a cheating mode to link bismuth ions to form a 2D sheet network. These sheets are further connected by hydrogen bonding interactions to give an interesting 3D supramolecular framework. 2D correlation analysis of IR of 1 with thermal and magnetic perturbation was introduced to ascertain the characteristic adsorption of the groups overlapped in the 1D IR spectrum. Additionally, compound 1 exhibits fluorescent emission at room temperature.展开更多
采用红外光谱并结合二维相关红外光谱法对生三七和熟三七进行了研究,分析比较三七炮制前后化学成分的变化。在一维红外谱图上,生三七和熟三七在1200~400 cm -1波段内的相似度较高,不同的是熟三七在2925,2855,1746,1460,1376,11...采用红外光谱并结合二维相关红外光谱法对生三七和熟三七进行了研究,分析比较三七炮制前后化学成分的变化。在一维红外谱图上,生三七和熟三七在1200~400 cm -1波段内的相似度较高,不同的是熟三七在2925,2855,1746,1460,1376,1158 cm -1出现了花生油的特征峰,这是由于采用煎炸法炮制三七所残留的花生油所引起的。两者药效组分的特征差异在二维相关红外谱图上显示得更为明显和直观,在1400~1700 cm-1区域,生三七仅在1650 cm-1附近有一个强自动峰,而熟三七在1469和1640 cm -1附近均有自动峰。在1120~1250 cm-1区域,生三七和熟三七共有1139(1137),1194(1196),1219(1221) cm -1三个自动峰,不同的是各自动峰的相对强度发生了变化,生三七经炮制后1139 cm -1峰的增强,而1194 cm -1峰减弱。二维相关红外光谱的变化规律说明了三七药材在炮制的过程中发生的主要变化是黄酮、糖类、皂苷等成分的分解。该方法揭示了三七在炮制过程中所发生的物理化学变化过程,从红外光谱的角度解释了三七“生消熟补”的药理。展开更多
基金supported by the NNSFC(No.21473030,1371033)Fujian Provincial Natural Science Foundation(2013J01042)the Open Fund of State Key Laboratory of Structural Chemistry(20130015)
文摘A three-dimensional (3D) Keggin-type heteropolytungstate{Zn(phen)3}3[ZnW12O40]·9H2O 1 (phen = 1,10-phenanthroline) has been synthesized through a conventional hydrothermal synthesis and was characterized by X-ray single-crystal diffraction analysis, X-ray powder diffraction (XRD), IR, UV-DRS, thermogravimetric analysis (TGA), thermal-dependent 2D-IR correlation spectroscopy (2D-COS IR) and Raman spectrum. Crystal data for compound 1: trigonal system, space group R3 with a = b = 25.268(4), c = 17.462(5) A, ), = 120°, V= 9655(4) A3 and Z = 3. Compound 1 is allomorphic to {Co(phen)3}3[CoW12O40]·9H2O 2, which has been reported by Feng Chai et al. In compound 2, its prominent feature is that the decisive role of water molecules (O-H…O) builds a 3D supramolecular structure. However, in the structure of compound 1, the interlayer space is filled by Zn(phen)3]2+ cations which linked the layers via C-H…O hydrogen bonding interactions to construct a three-dimensional framework. Two compounds are different in weak interactions, so we identify them by Thermal-dependent 2D-COS IR. Moreover, the fluorescence of compound 1 was also described.
基金This work is by the National Natural Science Foundation of China(No.22203006,No.21927901,No.92261206,No.21627805,No.12174012,No.21673004,No.21821004,No.21674001,and No.21790363)Ministry of Science and Technology of China(a special talent program)and the Beijing City.
文摘Equilibrium photoproduct of 7r-cyclopentadienyliron dicarbonyl dimer [CpFe(CO)2]2 in non- polar solvent carbon tetrachloride (CC14) is investigated using time-resolved 2D IR spec- troscopy. One of the several possible visible-light-driven photoreaction pathways is confirmed and the product is found to contain a di-carbonyl group that exhibits quantum beating be- tween two equivalent transitions in time-resolved 2D IR spectra, which turns out to be the anti-symmetric and symmetric stretching of the terminal carbonyl stretching modes of CpFe(CO)2C1. This is the main product and its reaction pathway involves radical formation, followed by chloride addition. Quantum-chemistry computations support these experimental results. Our results indicate that 2D IR method can be used to identify in situ structures and dynamics of chemical species involved in condensed-phase chemical reactions.
基金supported by the National Natural Science Foundation of China (No. 20873021)the State Key Laboratory of Structure Chemistry and the Young Talent Programmed of Fujian Province (No. 2006F3072)
文摘A new compound {[Bi(trans-DAM)(cis-DAM)(H2O)]NO3·H2O}n 1 derived from bismuth and the flexible ligand N,N'-diacetic acid imidazolium chloride (H2DAMCl) was obtained by hydrothermal synthesis and characterized by single-crystal X-ray diffraction. Compound 1 crystallizes in the monoclinic P21/c space group with a = 9.2298(18), b = 13.339(3), c = 17.090(3) , β = 105.38(2)°, V = 2028.7(7)A^3, Z = 4, C14H18N5O13Bi, Mr = 673.31, Dc = 2.204 g/cm^3, F(000) = 1296, μ = 8.772 mm-1, the final R = 0.0472 and wR = 0.1441 for 4129 observed reflections (I 〉 2σ(I)). In 1, the carboxylic groups from DAM- ligands adopt a cheating mode to link bismuth ions to form a 2D sheet network. These sheets are further connected by hydrogen bonding interactions to give an interesting 3D supramolecular framework. 2D correlation analysis of IR of 1 with thermal and magnetic perturbation was introduced to ascertain the characteristic adsorption of the groups overlapped in the 1D IR spectrum. Additionally, compound 1 exhibits fluorescent emission at room temperature.
文摘采用红外光谱并结合二维相关红外光谱法对生三七和熟三七进行了研究,分析比较三七炮制前后化学成分的变化。在一维红外谱图上,生三七和熟三七在1200~400 cm -1波段内的相似度较高,不同的是熟三七在2925,2855,1746,1460,1376,1158 cm -1出现了花生油的特征峰,这是由于采用煎炸法炮制三七所残留的花生油所引起的。两者药效组分的特征差异在二维相关红外谱图上显示得更为明显和直观,在1400~1700 cm-1区域,生三七仅在1650 cm-1附近有一个强自动峰,而熟三七在1469和1640 cm -1附近均有自动峰。在1120~1250 cm-1区域,生三七和熟三七共有1139(1137),1194(1196),1219(1221) cm -1三个自动峰,不同的是各自动峰的相对强度发生了变化,生三七经炮制后1139 cm -1峰的增强,而1194 cm -1峰减弱。二维相关红外光谱的变化规律说明了三七药材在炮制的过程中发生的主要变化是黄酮、糖类、皂苷等成分的分解。该方法揭示了三七在炮制过程中所发生的物理化学变化过程,从红外光谱的角度解释了三七“生消熟补”的药理。