Keggin type heteropolyacids was found to be an efficient and reusable catalyst for the synthesis of biologically active quinoxaline derivatives from the condensation of 1,2-diamine with 1,2-dicarbonyl compounds in exc...Keggin type heteropolyacids was found to be an efficient and reusable catalyst for the synthesis of biologically active quinoxaline derivatives from the condensation of 1,2-diamine with 1,2-dicarbonyl compounds in excellent yields in water. This method provides a new and efficient protocol in terms of small quantity of catalyst, a wide scope of substrates, and simple work-up procedure.展开更多
Four polyoxometalate complexes, (CPFX·HCl)_3H_4SiW_~12 O_~40 , (CPFX·HCl)_3H_3PW_~12 O_~40 , (CPFX·HCl)_3H_3PMo_~12 O_~40 and (CPFX·HCl)_4H_4SiMo_~12 O_~40 , were prepared from ciprofloxacin hydroc...Four polyoxometalate complexes, (CPFX·HCl)_3H_4SiW_~12 O_~40 , (CPFX·HCl)_3H_3PW_~12 O_~40 , (CPFX·HCl)_3H_3PMo_~12 O_~40 and (CPFX·HCl)_4H_4SiMo_~12 O_~40 , were prepared from ciprofloxacin hydrochloride(CPFX·HCl) reacting with H_nXM_~12 O_~40 ·nH_2O(X=P,Si; M=W,Mo) in an aqueous solution, and characterized by elemental analysis, IR spectrometry and TG-DTA. The IR spectrum confirms the presence of Keggin-type anions of heteropoly acids and the characteristic functional groups of ciprofloxacin. The TG/DTA curves show that their thermal decomposition is a multi-step process including simultaneous collapse of the Keggin-type structure. At first, these compounds had a mass loss of water molecules, then several other mass losses occured due to the decomposition of ciprofloxacin hydrochloride and its fragments with the degradation of Keggin anions. The end product of decomposition is the mixture of WO_3(or MoO_3) and SiO_2(or P_2O_5), identified by X-ray diffraction and IR spectroscopy. The possible thermal decomposition mechanisms of these complexes are proposed. This study exemplified that the thermal stability of the complexes containing tungsten is much better than that of the complexes containing molybdenum.展开更多
The title compounds 2ac were synthesized and characterized for the first time. Their proton numbers are around 3.2±0.15 and are not in proportion with the valid acidity-basicity of the central phosphonic acids. ...The title compounds 2ac were synthesized and characterized for the first time. Their proton numbers are around 3.2±0.15 and are not in proportion with the valid acidity-basicity of the central phosphonic acids. The entirety of phosphonic acids 1a-c is as the coordinate center of heteropoly anions of 2ac.展开更多
In this paper,One novel Keggin type polyoxomolybdate compounds have been hydrothermal synthesized:{[(CH3)2NH2]4(SiMo12O40)}[(CH3)2NH]·(DMF)0.5(1).The compound 1have been characterized by infrared spectrum,and the...In this paper,One novel Keggin type polyoxomolybdate compounds have been hydrothermal synthesized:{[(CH3)2NH2]4(SiMo12O40)}[(CH3)2NH]·(DMF)0.5(1).The compound 1have been characterized by infrared spectrum,and the two-dimensional infrared correlation spectroscopy.展开更多
Two charge-transfer complexes of 2a and 2b of Keggin type were synthesized and characterized by elemental analysis, IR spectra, UV spectra, XRD, TG-DSC; and were compared with Hquin-PW12. The primary structure of the...Two charge-transfer complexes of 2a and 2b of Keggin type were synthesized and characterized by elemental analysis, IR spectra, UV spectra, XRD, TG-DSC; and were compared with Hquin-PW12. The primary structure of the heteropolyanions had not been changed after the formation of the charge transfer complexes.展开更多
Two unusual complexes [Cda（Do）4（H2O）2CI]（PW12O4O）＇2H2O （1） and [Aga（Do）6（PW12O40）][Ag（Do）2]2（PW12O4O）＇2H2O （2） were hydrothermally synthesized by the combination of two different metallic salts, Ke...Two unusual complexes [Cda（Do）4（H2O）2CI]（PW12O4O）＇2H2O （1） and [Aga（Do）6（PW12O40）][Ag（Do）2]2（PW12O4O）＇2H2O （2） were hydrothermally synthesized by the combination of two different metallic salts, Keggin-type polyoxometalate and 1,10-phen-5,6-dione （Do）, and characterized by elemental analyses, inductively coupled plasma analyses, infrared spectra, X-ray photoelectron spectroscopy, thermal gravimetry, photoluminescent spectra and single-crystal X-ray diffraction analyses. Crystal 1 is of monoclinic, space group P21/n with a = 12.383（3）, b = 18.326（4）, c = 16.437（3） A, β = 90.29（3）°, V = 3730.1（13） A3, Z = 2, CdzCasH32NsC1052PW12, Mr. = 4050.24, Dc = 3.604 g＇cm-3,μ（MoKa） = 19.145 mm1, F（000） = 3608, GOOF = 1.168, the final R = 0.0569 and wR = 0.0745 for 5715 observed reflections （1 〉 2σ（I））. Crystal 2 is of triclinic, space group Pi with a = 13.959（5）, b = 16.972（5）, c = 17.647（5）A, α = 85.970（5）, β = 81.353（5）, γ = 86.316（5）°, V = 4117（2） A3 Z = 1, Ag6C120H64N200102P2W24, Mr. = 8539.47, Dc = 3.444 g-cm-3,μ（MoKa） = 17.511 mm-1, F（000） = 3828, GOOF = 1.033, the final R = 0.0981 and wR = 0.1658 for 9906 observed reflections （I 〉 2σ（I））. Structural analyses show that complex 1 has a zero dimensional structure, which is further assembled into a one-dimensional ladder-like structure through hydrogen bonds. Complex 2 possesses a one-dimensional chain structure. Furthermore, solid-state luminescent spectra of complexes 1 and 2 indicate red and green fluorescent emission, respectively.展开更多
The novel class of inorganic nanoclusters, \{\[AlO\-4Al\-\{12\}(OH)\-\{24\}(H\-2O)\-\{12\}\]\}\{\[SiW\-\{11\}O\-\{39\}CoCl\]\}\511H\-2O, \{\[AlO\-4Al\-\{12\}(OH)\-\{24\}(H\-2O)\-\{12\}\]\}\{\[P\-2W\-\{18\}O\-\{62\}\]\...The novel class of inorganic nanoclusters, \{\[AlO\-4Al\-\{12\}(OH)\-\{24\}(H\-2O)\-\{12\}\]\}\{\[SiW\-\{11\}O\-\{39\}CoCl\]\}\511H\-2O, \{\[AlO\-4Al\-\{12\}(OH)\-\{24\}(H\-2O)\-\{12\}\]\}\{\[P\-2W\-\{18\}O\-\{62\}\]\}Cl\533H\-2O and \{\[AlO\-4Al\-\{12\}(OH)\-\{24\}(H\-2O)\-\{12\}\]\}\-2\[NaP\-5W\-\{30\}O\-\{110\}\]\524H\-2O, consisting of Keggin cations and heteropolyoxometalates, has been synthesized and characterized by ICP, IR and NMR. It is proved that the intrinsic identities of Keggin cation and heteropolyanions of the clusters are preserved within the gels.展开更多
文摘Keggin type heteropolyacids was found to be an efficient and reusable catalyst for the synthesis of biologically active quinoxaline derivatives from the condensation of 1,2-diamine with 1,2-dicarbonyl compounds in excellent yields in water. This method provides a new and efficient protocol in terms of small quantity of catalyst, a wide scope of substrates, and simple work-up procedure.
文摘Four polyoxometalate complexes, (CPFX·HCl)_3H_4SiW_~12 O_~40 , (CPFX·HCl)_3H_3PW_~12 O_~40 , (CPFX·HCl)_3H_3PMo_~12 O_~40 and (CPFX·HCl)_4H_4SiMo_~12 O_~40 , were prepared from ciprofloxacin hydrochloride(CPFX·HCl) reacting with H_nXM_~12 O_~40 ·nH_2O(X=P,Si; M=W,Mo) in an aqueous solution, and characterized by elemental analysis, IR spectrometry and TG-DTA. The IR spectrum confirms the presence of Keggin-type anions of heteropoly acids and the characteristic functional groups of ciprofloxacin. The TG/DTA curves show that their thermal decomposition is a multi-step process including simultaneous collapse of the Keggin-type structure. At first, these compounds had a mass loss of water molecules, then several other mass losses occured due to the decomposition of ciprofloxacin hydrochloride and its fragments with the degradation of Keggin anions. The end product of decomposition is the mixture of WO_3(or MoO_3) and SiO_2(or P_2O_5), identified by X-ray diffraction and IR spectroscopy. The possible thermal decomposition mechanisms of these complexes are proposed. This study exemplified that the thermal stability of the complexes containing tungsten is much better than that of the complexes containing molybdenum.
文摘The title compounds 2ac were synthesized and characterized for the first time. Their proton numbers are around 3.2±0.15 and are not in proportion with the valid acidity-basicity of the central phosphonic acids. The entirety of phosphonic acids 1a-c is as the coordinate center of heteropoly anions of 2ac.
基金the NNSFC(21473030,1371033)Fujian Provincial Natural ScienceFoundation(2013J01042)the Open Fund of State Key Laboratory of Structural Chemistry(20130015)
文摘In this paper,One novel Keggin type polyoxomolybdate compounds have been hydrothermal synthesized:{[(CH3)2NH2]4(SiMo12O40)}[(CH3)2NH]·(DMF)0.5(1).The compound 1have been characterized by infrared spectrum,and the two-dimensional infrared correlation spectroscopy.
文摘Two charge-transfer complexes of 2a and 2b of Keggin type were synthesized and characterized by elemental analysis, IR spectra, UV spectra, XRD, TG-DSC; and were compared with Hquin-PW12. The primary structure of the heteropolyanions had not been changed after the formation of the charge transfer complexes.
基金Program for New Century Excellent Talents in University(NCET-10-0176)of ChinaNatural Science Foundation Project of Jiangsu University(No.09JDG001,No.11jdg104 and BK2011528)
文摘Two unusual complexes [Cda（Do）4（H2O）2CI]（PW12O4O）＇2H2O （1） and [Aga（Do）6（PW12O40）][Ag（Do）2]2（PW12O4O）＇2H2O （2） were hydrothermally synthesized by the combination of two different metallic salts, Keggin-type polyoxometalate and 1,10-phen-5,6-dione （Do）, and characterized by elemental analyses, inductively coupled plasma analyses, infrared spectra, X-ray photoelectron spectroscopy, thermal gravimetry, photoluminescent spectra and single-crystal X-ray diffraction analyses. Crystal 1 is of monoclinic, space group P21/n with a = 12.383（3）, b = 18.326（4）, c = 16.437（3） A, β = 90.29（3）°, V = 3730.1（13） A3, Z = 2, CdzCasH32NsC1052PW12, Mr. = 4050.24, Dc = 3.604 g＇cm-3,μ（MoKa） = 19.145 mm1, F（000） = 3608, GOOF = 1.168, the final R = 0.0569 and wR = 0.0745 for 5715 observed reflections （1 〉 2σ（I））. Crystal 2 is of triclinic, space group Pi with a = 13.959（5）, b = 16.972（5）, c = 17.647（5）A, α = 85.970（5）, β = 81.353（5）, γ = 86.316（5）°, V = 4117（2） A3 Z = 1, Ag6C120H64N200102P2W24, Mr. = 8539.47, Dc = 3.444 g-cm-3,μ（MoKa） = 17.511 mm-1, F（000） = 3828, GOOF = 1.033, the final R = 0.0981 and wR = 0.1658 for 9906 observed reflections （I 〉 2σ（I））. Structural analyses show that complex 1 has a zero dimensional structure, which is further assembled into a one-dimensional ladder-like structure through hydrogen bonds. Complex 2 possesses a one-dimensional chain structure. Furthermore, solid-state luminescent spectra of complexes 1 and 2 indicate red and green fluorescent emission, respectively.
文摘The novel class of inorganic nanoclusters, \{\[AlO\-4Al\-\{12\}(OH)\-\{24\}(H\-2O)\-\{12\}\]\}\{\[SiW\-\{11\}O\-\{39\}CoCl\]\}\511H\-2O, \{\[AlO\-4Al\-\{12\}(OH)\-\{24\}(H\-2O)\-\{12\}\]\}\{\[P\-2W\-\{18\}O\-\{62\}\]\}Cl\533H\-2O and \{\[AlO\-4Al\-\{12\}(OH)\-\{24\}(H\-2O)\-\{12\}\]\}\-2\[NaP\-5W\-\{30\}O\-\{110\}\]\524H\-2O, consisting of Keggin cations and heteropolyoxometalates, has been synthesized and characterized by ICP, IR and NMR. It is proved that the intrinsic identities of Keggin cation and heteropolyanions of the clusters are preserved within the gels.
