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2015 Volume 34 Issue 4
2015, 34(4): 467-480
doi: 10.14102/j.cnki.0254-5861.2011-0548
Abstract:
The comparative study of charge effect on the size-dependence stabilities of gold clusters Aunz (n=2~12, z=0/±1) in gas phase is performed at the M06-L/Lanl2dz level. The lowest-energy structures charged by -1, 0 and +1 are optimized. The result shows that the geometries of the clusters with over 7 atoms tend to be cake-like. From the two-to three-dimensional geometries, the oscillatory behaviors are exhibited in the structural and electronic properties with the most pronounced in energy gap. The amplitude for the positive clusters is bigger than both the neutral and negative clusters. The neutral clusters with even number of even-coordinated atoms are more stable than the neighbors with odd number of even-coordinated atoms, as is completely reversed for the charged clusters. The oscillatory behaviors for the charged clusters are opposite to that for the neutral clusters, as is attributed to the electron-paired effect.
The comparative study of charge effect on the size-dependence stabilities of gold clusters Aunz (n=2~12, z=0/±1) in gas phase is performed at the M06-L/Lanl2dz level. The lowest-energy structures charged by -1, 0 and +1 are optimized. The result shows that the geometries of the clusters with over 7 atoms tend to be cake-like. From the two-to three-dimensional geometries, the oscillatory behaviors are exhibited in the structural and electronic properties with the most pronounced in energy gap. The amplitude for the positive clusters is bigger than both the neutral and negative clusters. The neutral clusters with even number of even-coordinated atoms are more stable than the neighbors with odd number of even-coordinated atoms, as is completely reversed for the charged clusters. The oscillatory behaviors for the charged clusters are opposite to that for the neutral clusters, as is attributed to the electron-paired effect.
2015, 34(4): 481-487
doi: 10.14102/j.cnki.0254-5861.2011-0551
Abstract:
X2Si=Ge: (X=H, Me, F, Cl, Br, Ph, Ar…) is a new species. Its cycloaddition reaction is a new area for the study of germylene chemistry. The mechanism of cycloaddition reaction between singlet state Me2Si=Ge: and formaldehyde has been investigated with the CCSD(T)//MP2/cc-pvtz method. From the potential energy profile, it could be predicted that the reaction has one dominant reaction pathway. The reaction rule presented is that the two reactants first form a four-membered Si-heterocyclic ring germylene through the [2+2] cycloaddition reaction. Because of the 4p unoccupied orbital of Ge: atom in the four-membered Si-heterocyclic ring germylene and the π orbital of formaldehyde form a π→p donor-acceptor bond, the four-membered Si-heterocyclic ring germylene further combines with formaldehyde to form an intermediate. Because the Ge atom in the intermediate undergoes sp3 hybridization after transition state, then the intermediate isomerizes to a spiro-Ge-heterocyclic ring compound involving Si via a transition state. The research result indicates the laws of cycloaddition reaction between H2Si=Ge: and formaldehyde. It has important reference value for the cycloaddition reaction between X2Si=Ge: (X=H, Me, F, Cl, Br, Ph, Ar…) and asymmetric π-bonded compounds, which is significant for the synthesis of small-ring and spiro-Ge-heterocyclic compounds involving Si. The study extends research area and enriches the research content of germylene chemistry.
X2Si=Ge: (X=H, Me, F, Cl, Br, Ph, Ar…) is a new species. Its cycloaddition reaction is a new area for the study of germylene chemistry. The mechanism of cycloaddition reaction between singlet state Me2Si=Ge: and formaldehyde has been investigated with the CCSD(T)//MP2/cc-pvtz method. From the potential energy profile, it could be predicted that the reaction has one dominant reaction pathway. The reaction rule presented is that the two reactants first form a four-membered Si-heterocyclic ring germylene through the [2+2] cycloaddition reaction. Because of the 4p unoccupied orbital of Ge: atom in the four-membered Si-heterocyclic ring germylene and the π orbital of formaldehyde form a π→p donor-acceptor bond, the four-membered Si-heterocyclic ring germylene further combines with formaldehyde to form an intermediate. Because the Ge atom in the intermediate undergoes sp3 hybridization after transition state, then the intermediate isomerizes to a spiro-Ge-heterocyclic ring compound involving Si via a transition state. The research result indicates the laws of cycloaddition reaction between H2Si=Ge: and formaldehyde. It has important reference value for the cycloaddition reaction between X2Si=Ge: (X=H, Me, F, Cl, Br, Ph, Ar…) and asymmetric π-bonded compounds, which is significant for the synthesis of small-ring and spiro-Ge-heterocyclic compounds involving Si. The study extends research area and enriches the research content of germylene chemistry.
2015, 34(4): 488-496
doi: 10.14102/j.cnki.0254-5861.2011-0603
Abstract:
In this work, atrazine functions as a template molecule, and trifluoromethacrylic acid (TFMAA), methacrylic acid (MAA), methyl methacrylate (MMA), and acrylamide (AM) serve as functional monomers, respectively. By using density functional theory (DFT), the computational approach was carried out to simulate the self-assembly system of template and functional monomer. The geometry optimization, action sites, binding energies, and molecular imprinting mechanism of complexes with different functional monomers in different proportions were predicted. The simulation results showed that atrazine and the functional monomers interacted through hydrogen bond. Among the 4 functional monomers, the imprinted complex formed by TFMAA and atrazine with a ratio of (1:6) has the lowest binding energy and the best imprinting effect. Then, the microspheres of molecularly imprinted polymer (MIPs) were prepared by precipitating polymerization using atrazine as the template molecule and TFMAA as the functional monomer. The microspheres were observed by scanning electron microscopy (SEM). The results showed that atrazine MIP microspheres had average particle size of 400 nm, which was greater than the non-imprinted polymeric microspheres (NIPs). Dynamic adsorption experiments of MIPs showed that the adsorption reaction reached balance after 200 min. Analysis of the Scatchard plot revealed that the binding sites of MIPs to atrazine were equal class under the studied concentration range. The dissociation constant (Kd) and apparent maximum adsorption quantity (Qmax) of MIPs were 3.6×10-5mol/L and 4.83 μmol/g, respectively. The study of selective adsorption between atrazine and metribuzin showed that imprinted microspheres had high selectivity for the template molecule atrazine.
In this work, atrazine functions as a template molecule, and trifluoromethacrylic acid (TFMAA), methacrylic acid (MAA), methyl methacrylate (MMA), and acrylamide (AM) serve as functional monomers, respectively. By using density functional theory (DFT), the computational approach was carried out to simulate the self-assembly system of template and functional monomer. The geometry optimization, action sites, binding energies, and molecular imprinting mechanism of complexes with different functional monomers in different proportions were predicted. The simulation results showed that atrazine and the functional monomers interacted through hydrogen bond. Among the 4 functional monomers, the imprinted complex formed by TFMAA and atrazine with a ratio of (1:6) has the lowest binding energy and the best imprinting effect. Then, the microspheres of molecularly imprinted polymer (MIPs) were prepared by precipitating polymerization using atrazine as the template molecule and TFMAA as the functional monomer. The microspheres were observed by scanning electron microscopy (SEM). The results showed that atrazine MIP microspheres had average particle size of 400 nm, which was greater than the non-imprinted polymeric microspheres (NIPs). Dynamic adsorption experiments of MIPs showed that the adsorption reaction reached balance after 200 min. Analysis of the Scatchard plot revealed that the binding sites of MIPs to atrazine were equal class under the studied concentration range. The dissociation constant (Kd) and apparent maximum adsorption quantity (Qmax) of MIPs were 3.6×10-5mol/L and 4.83 μmol/g, respectively. The study of selective adsorption between atrazine and metribuzin showed that imprinted microspheres had high selectivity for the template molecule atrazine.
2015, 34(4): 497-502
doi: 10.14102/j.cnki.0254-5861.2011-0558
Abstract:
The title compound N-(2-hydroxy-3-(4-(2-methoxyphenyl)piperazin-1-yl)propyl)-quinoxaline-2-methanamide (4, C23H27N5O3, Mr=421.50) was synthesized via a four-step reaction and characterized by 1H NMR, 13C NMR, ESIMS and single-crystal X-ray diffraction. The crystal is of monoclinic, space group P21/n with a=12.108(2), b=12.639(3), c=14.601(3)Å, β=104.87(3)°, V=2159.6(8)Å3, Z=4, Dc=1.296 g/cm3, S=1.023, μ=0.088 mm-1, F(000)=896, R=0.0392 and wR=0.0983 for 2836 observed reflections with I>2σ(I). The single-crystal X-ray structural analysis reveals that 4 is stabilized by intramolecular and intermolecular hydrogen bonds together with π-π interactions. The bioassay showed that 4 exhibited high selective activity for α1A/Dvs. α1B-adrenoceptors subtype.
The title compound N-(2-hydroxy-3-(4-(2-methoxyphenyl)piperazin-1-yl)propyl)-quinoxaline-2-methanamide (4, C23H27N5O3, Mr=421.50) was synthesized via a four-step reaction and characterized by 1H NMR, 13C NMR, ESIMS and single-crystal X-ray diffraction. The crystal is of monoclinic, space group P21/n with a=12.108(2), b=12.639(3), c=14.601(3)Å, β=104.87(3)°, V=2159.6(8)Å3, Z=4, Dc=1.296 g/cm3, S=1.023, μ=0.088 mm-1, F(000)=896, R=0.0392 and wR=0.0983 for 2836 observed reflections with I>2σ(I). The single-crystal X-ray structural analysis reveals that 4 is stabilized by intramolecular and intermolecular hydrogen bonds together with π-π interactions. The bioassay showed that 4 exhibited high selective activity for α1A/Dvs. α1B-adrenoceptors subtype.
2015, 34(4): 503-509
doi: 10.14102/j.cnki.0254-5861.2011-0563
Abstract:
The title compounds 2-phenylsulfonylhydrazono-3-(3-trifluoromethylphenyl)-2(3H)-thiazoline derivatives were designed and synthesized via the reaction of thiosemicarbazides with chloroacetaldehyde, and their chemical structures were characterized by 1H NMR, 13C NMR, elemental analysis and MS. Furthermore, 4a was characterized by single-crystal X-ray diffraction. The target compound 4a (C16H12F3N3O2S2, Mr=399.41) crystallized in monoclinic system, P21/c space group with a=7.7457(4), b=13.5850(7), c=16.5455(10)Å, β=99.698(2)°, V=1656.30(16)Å3, Dc=1.602 g/cm3, Z=4, F(000)=816, λ=0.71070Å, μ(MoKα)=0.370 mm-1, R=0.072 and wR=0.0867. The crystal structure of 4a revealed the cyclization of thiosemicarbazide moiety with chloroacetaldehyde at the N(1) position. The title compounds exhibited good insecticidal activity against spider mite (Tetranychus cinnabarinus Boisduval) and favorable fungicidal activity against Corynespora cassiicola.
The title compounds 2-phenylsulfonylhydrazono-3-(3-trifluoromethylphenyl)-2(3H)-thiazoline derivatives were designed and synthesized via the reaction of thiosemicarbazides with chloroacetaldehyde, and their chemical structures were characterized by 1H NMR, 13C NMR, elemental analysis and MS. Furthermore, 4a was characterized by single-crystal X-ray diffraction. The target compound 4a (C16H12F3N3O2S2, Mr=399.41) crystallized in monoclinic system, P21/c space group with a=7.7457(4), b=13.5850(7), c=16.5455(10)Å, β=99.698(2)°, V=1656.30(16)Å3, Dc=1.602 g/cm3, Z=4, F(000)=816, λ=0.71070Å, μ(MoKα)=0.370 mm-1, R=0.072 and wR=0.0867. The crystal structure of 4a revealed the cyclization of thiosemicarbazide moiety with chloroacetaldehyde at the N(1) position. The title compounds exhibited good insecticidal activity against spider mite (Tetranychus cinnabarinus Boisduval) and favorable fungicidal activity against Corynespora cassiicola.
2015, 34(4): 510-522
doi: 10.14102/j.cnki.0254-5861.2011-0521
Abstract:
In order to study the structure of lotus (Nelumbo nucifera Gaertn) seed oligosaccharides and their effect on the proliferation of Bifidobacterium adolescentis, we extracted the oligosaccharides from seeds collected from Jianning County, China. We preliminarily characterized the groups, molecular weights, molecular formulae, component monosaccharides and glycosidic bonds using mass spectrometry (MS) and nuclear magnetic resonance (NMR) after isolation and purification. The lotus seed oligosaccharides contained glycosidic bonds Manp-(1→), Galp-(1→), α(1→6)-Glup and α(1→6)-Manp; and mannose was the chief component monosaccharide. NMR analyses showed that α-glycosidic bonds and pyranoid rings were predominant in the oligosaccharides. The MS analyses showed that lotus seed oligosaccharides consisted of three oligosaccharides of different polymerization degree, with relative molecular weights of 342, 504 and 666 Da, and corresponding molecular formulae C12H22O11, C18H32O16 and C24H42O21. Research on the effect of lotus seed oligosaccharides on the proliferation of B. adolescentis showed that they effectively promoted the production of acetic, propionic and butyric acids by B. adolescentis through fermentation, and their effect was stronger than that of fructo-, xylo- and isomalto-oligosaccharides. Lotus seed oligosaccharides have potential as a new functional probiotic and lotus seeds should be further explored and utilized as a source of oligosaccharides.
In order to study the structure of lotus (Nelumbo nucifera Gaertn) seed oligosaccharides and their effect on the proliferation of Bifidobacterium adolescentis, we extracted the oligosaccharides from seeds collected from Jianning County, China. We preliminarily characterized the groups, molecular weights, molecular formulae, component monosaccharides and glycosidic bonds using mass spectrometry (MS) and nuclear magnetic resonance (NMR) after isolation and purification. The lotus seed oligosaccharides contained glycosidic bonds Manp-(1→), Galp-(1→), α(1→6)-Glup and α(1→6)-Manp; and mannose was the chief component monosaccharide. NMR analyses showed that α-glycosidic bonds and pyranoid rings were predominant in the oligosaccharides. The MS analyses showed that lotus seed oligosaccharides consisted of three oligosaccharides of different polymerization degree, with relative molecular weights of 342, 504 and 666 Da, and corresponding molecular formulae C12H22O11, C18H32O16 and C24H42O21. Research on the effect of lotus seed oligosaccharides on the proliferation of B. adolescentis showed that they effectively promoted the production of acetic, propionic and butyric acids by B. adolescentis through fermentation, and their effect was stronger than that of fructo-, xylo- and isomalto-oligosaccharides. Lotus seed oligosaccharides have potential as a new functional probiotic and lotus seeds should be further explored and utilized as a source of oligosaccharides.
2015, 34(4): 523-528
doi: 10.14102/j.cnki.0254-5861.2011-0582
Abstract:
The target compound (C58H74N6O10) has been structurally determined by singlecrystal X-ray diffraction. The crystal is in the monoclinic system, space group C2/c, with a=22.08(3), b=12.628(19), c=21.73(3)Å, β=106.78(3)°, C58H74N6O10, Mr=1015.23, Dc=1.16239 g/cm3, V=5801(14)Å3, Z=4, F(000)=2176, μ(MoKa)=0.080 mm-1, T=293(2) K, 5107 independent reflections with 3125 observed ones (I>2σ(I)), R=0.0768 and wR=0.2305 with GOF=1.025 (R=0.1129 and wR=0.2674 for all data). The calixarene moiety maintains the symmetric cone conformation through intramolecular O-H…O and N-H…O hydrogen bonds. The thermal analysis showed that the decomposition mechanism of compound 3 is complex. Fluorescence spectra of 3 exhibited an emission band at 423 nm when excited with 360 nm radiation at room temperature in DMF.
The target compound (C58H74N6O10) has been structurally determined by singlecrystal X-ray diffraction. The crystal is in the monoclinic system, space group C2/c, with a=22.08(3), b=12.628(19), c=21.73(3)Å, β=106.78(3)°, C58H74N6O10, Mr=1015.23, Dc=1.16239 g/cm3, V=5801(14)Å3, Z=4, F(000)=2176, μ(MoKa)=0.080 mm-1, T=293(2) K, 5107 independent reflections with 3125 observed ones (I>2σ(I)), R=0.0768 and wR=0.2305 with GOF=1.025 (R=0.1129 and wR=0.2674 for all data). The calixarene moiety maintains the symmetric cone conformation through intramolecular O-H…O and N-H…O hydrogen bonds. The thermal analysis showed that the decomposition mechanism of compound 3 is complex. Fluorescence spectra of 3 exhibited an emission band at 423 nm when excited with 360 nm radiation at room temperature in DMF.
2015, 34(4): 529-535
doi: 10.14102/j.cnki.0254-5861.2011-0588
Abstract:
Ce1-xBixO2-δ (x=0.00, 0.03, 0.05, 0.07, 0.10, 0.15, 0.30) solid solutions were synthesized via a hydrothermal method. The structure, spectra and electrochemical transport properties of the samples were characterized systematically. The powder X-ray diffraction analysis showed that all of the doped samples exhibited single phase fluorite structure. The particle sizes decreased from 18 to 9 nm and the lattice parameters increased gradually with the dopant content increasing from x=0.03 to x=0.30. The Bi3+ doping also induced the F2g Raman peak to shift from 463 to 455 cm-1, and caused a red shift of the band gap energies calculated from UV-Vis spectra. The impedance plots at different temperature demonstrated that the boundary resistance was much larger than the grain resistance, and two activation energy values were obtained in different temperature range.
Ce1-xBixO2-δ (x=0.00, 0.03, 0.05, 0.07, 0.10, 0.15, 0.30) solid solutions were synthesized via a hydrothermal method. The structure, spectra and electrochemical transport properties of the samples were characterized systematically. The powder X-ray diffraction analysis showed that all of the doped samples exhibited single phase fluorite structure. The particle sizes decreased from 18 to 9 nm and the lattice parameters increased gradually with the dopant content increasing from x=0.03 to x=0.30. The Bi3+ doping also induced the F2g Raman peak to shift from 463 to 455 cm-1, and caused a red shift of the band gap energies calculated from UV-Vis spectra. The impedance plots at different temperature demonstrated that the boundary resistance was much larger than the grain resistance, and two activation energy values were obtained in different temperature range.
2015, 34(4): 536-542
doi: 10.14102/j.cnki.0254-5861.2011-0591
Abstract:
A new cadmium(Ⅱ) coordination polymer with unique structure was synthesized under diffusion process by employing triangular N-containing ligand tris(4-(pyridyl) phenyl) amine (Tppa). Complex 1 crystallizes in the space group Pbcn, with a=28.906(3), b=13.5294(14), c=17.8727(18)Å, V=6989.7(12)Å3, C66H48CdCl2N8, Mr=1136.42, Dc=1.080 g/cm3, F(000)=2328, μ=0.428 mm-1 and Z=4. Complex 1 features a 2D→3D framework with the coexistence of inclined polycatenation and polythreading. In addition, the luminescent property of complex 1 was studied.
A new cadmium(Ⅱ) coordination polymer with unique structure was synthesized under diffusion process by employing triangular N-containing ligand tris(4-(pyridyl) phenyl) amine (Tppa). Complex 1 crystallizes in the space group Pbcn, with a=28.906(3), b=13.5294(14), c=17.8727(18)Å, V=6989.7(12)Å3, C66H48CdCl2N8, Mr=1136.42, Dc=1.080 g/cm3, F(000)=2328, μ=0.428 mm-1 and Z=4. Complex 1 features a 2D→3D framework with the coexistence of inclined polycatenation and polythreading. In addition, the luminescent property of complex 1 was studied.
2015, 34(4): 543-550
doi: 10.14102/j.cnki.0254-5861.2011-0537
Abstract:
Two new Cu(Ⅱ) coordination polymers, [Cu2(tbph)2(btb)2]n (1) and {[Cu2(tbph)2-(bth)2]·H2O}n (2), (H2tbph=4-tert-butyl-phthalic acid, btb=1,4-bis(1,2,4-triazol-1-yl)butane, bth=1,6-bis(1,2,4-triazol-1-yl)hexane), have been synthesized and characterized by elemental analysis, FT-IR and X-ray single-crystal diffraction. Complex 1 has a 2D sql layer. Complex 2 shows a (3,4)-connected 2D sheet with a (4.64.8)(4.82) topology. The thermal behavior of the two corresponding complexes has briefly been investigated.
Two new Cu(Ⅱ) coordination polymers, [Cu2(tbph)2(btb)2]n (1) and {[Cu2(tbph)2-(bth)2]·H2O}n (2), (H2tbph=4-tert-butyl-phthalic acid, btb=1,4-bis(1,2,4-triazol-1-yl)butane, bth=1,6-bis(1,2,4-triazol-1-yl)hexane), have been synthesized and characterized by elemental analysis, FT-IR and X-ray single-crystal diffraction. Complex 1 has a 2D sql layer. Complex 2 shows a (3,4)-connected 2D sheet with a (4.64.8)(4.82) topology. The thermal behavior of the two corresponding complexes has briefly been investigated.
2015, 34(4): 551-561
doi: 10.14102/j.cnki.0254-5861.2011-0574
Abstract:
Based on the building block of 2-phenyl-4,6-di(pyridin-2-yl)pyrimidine (L=C20H14N4), a Cu(Ⅰ) polymer [(CuC20H14N4)(CuCl2)]∞ and a salt with H2SO4 [(C20H16N4)(HSO4)2] have been synthesized by hydrothermal method and characterized by X-ray single-crystal diffraction. In the Cu(Ⅰ) polymer, although the central metal ions of Cu(Ⅰ) directly coordinate with the building block L, they still do not assembly expected grid-type complexes and there exists a one-dimensional chain constructed through coordinate bonds. In the salt, hydrogen bonds along with two kinds of π…π supramoleuclar interactions fabricate two-dimensional (2D) networks which further generate a 3D supramolecular architecture via interlayer π…π interactions. Fluorescent spectra show that the L emits blue fluorescence and its Cu(Ⅰ) polymer and salt decrease the fluorescent intensity.
Based on the building block of 2-phenyl-4,6-di(pyridin-2-yl)pyrimidine (L=C20H14N4), a Cu(Ⅰ) polymer [(CuC20H14N4)(CuCl2)]∞ and a salt with H2SO4 [(C20H16N4)(HSO4)2] have been synthesized by hydrothermal method and characterized by X-ray single-crystal diffraction. In the Cu(Ⅰ) polymer, although the central metal ions of Cu(Ⅰ) directly coordinate with the building block L, they still do not assembly expected grid-type complexes and there exists a one-dimensional chain constructed through coordinate bonds. In the salt, hydrogen bonds along with two kinds of π…π supramoleuclar interactions fabricate two-dimensional (2D) networks which further generate a 3D supramolecular architecture via interlayer π…π interactions. Fluorescent spectra show that the L emits blue fluorescence and its Cu(Ⅰ) polymer and salt decrease the fluorescent intensity.
2015, 34(4): 562-568
doi: 10.14102/j.cnki.0254-5861.2011-0571
Abstract:
The hydrothermal reaction of 5-benzylaminoisophthalic acid (H2BAIP) and Zn(CH3COO)2×2H2O in the presence of NaOH gave rise to a three-dimensional (3-D) metal-organic framework containing Zn(Ⅱ)-carboxylate chains, [Zn(BAIP)]n. Single-crystal X-ray diffraction analysis reveals that the complex crystallizes in trigonal space group R-3 with a=28.354(2), b=28.354(2), c=8.3821(8)Å, γ=120°, V=5836.0(10)Å3, Z=18, Mr=334.62, Dc=1.714 g×cm-3, μ=1.909 mm-1, S=1.162, F(000)=3060, the final R=0.0785 and wR=0.1121 for 2334 observed reflections (I>2σ(I)). Zn(Ⅱ) is in a distorted tetrahedral geometry, and BAIP serves as a μ4-bridge using two μ2,η2-bridging carboxylate groups. BAIP links Zn(Ⅱ) ions into a 3-D network containing hexagonal cavities. The coordination-inert benzyl occupies the void space of the large hexagonal cavities. The complex is thermally stable up to 410℃, and exhibits photoluminescent emission at 522 nm on 402 nm excitation.
The hydrothermal reaction of 5-benzylaminoisophthalic acid (H2BAIP) and Zn(CH3COO)2×2H2O in the presence of NaOH gave rise to a three-dimensional (3-D) metal-organic framework containing Zn(Ⅱ)-carboxylate chains, [Zn(BAIP)]n. Single-crystal X-ray diffraction analysis reveals that the complex crystallizes in trigonal space group R-3 with a=28.354(2), b=28.354(2), c=8.3821(8)Å, γ=120°, V=5836.0(10)Å3, Z=18, Mr=334.62, Dc=1.714 g×cm-3, μ=1.909 mm-1, S=1.162, F(000)=3060, the final R=0.0785 and wR=0.1121 for 2334 observed reflections (I>2σ(I)). Zn(Ⅱ) is in a distorted tetrahedral geometry, and BAIP serves as a μ4-bridge using two μ2,η2-bridging carboxylate groups. BAIP links Zn(Ⅱ) ions into a 3-D network containing hexagonal cavities. The coordination-inert benzyl occupies the void space of the large hexagonal cavities. The complex is thermally stable up to 410℃, and exhibits photoluminescent emission at 522 nm on 402 nm excitation.
2015, 34(4): 569-575
doi: 10.14102/j.cnki.0254-5861.2011-0567
Abstract:
Treatment of a heptadentate ligand 2,2'-(((pyridine-2,6-diyl-bis(methylene))-bis((pyridin-2-ylmethyl)azanediyl))bis(methylene))diphenol (H2L) possessing pyridinyl and phenolate groups, with three equivalents of Cu(ClO4)2·6H2O in methanol under base conditions, gave rise to a hexanuclear cluster complex [Cu6L2(OH)4](ClO4)4·4MeCN·0.5MeOH (1). Complex 1 crystallizes in triclinic, space group P1 with a=12.068(12), b=12.567(12), c=16.279(16)Å, α=105.694(12), β=93.631(13), γ=112.017(11)°, V=2166(4)Å3, Z=1, μ=1.651 mm-1, Dc=1.599 Mg/m3, T=296(2) K, C74.5H79.5N14O24.5Cl4Cu6, Mr=2086.12, F(000)=1062.5, S=1.061, R=0.0521 and wR=0.1270. In the cation of complex 1, the six copper cores are arranged into a two-parallel three-site strings configuration with each metal exhibits a slightly distorted square-pyramidal geometry, resulting from the connection of donor pyridinyl nitrogen and phenolate oxygen atoms in ligand H2L, and/or the oxygen donors in hydroxyl groups. In addition, magnetic susceptibility measurements revealed complex 1 displayed antiferromagnetic coupling.
Treatment of a heptadentate ligand 2,2'-(((pyridine-2,6-diyl-bis(methylene))-bis((pyridin-2-ylmethyl)azanediyl))bis(methylene))diphenol (H2L) possessing pyridinyl and phenolate groups, with three equivalents of Cu(ClO4)2·6H2O in methanol under base conditions, gave rise to a hexanuclear cluster complex [Cu6L2(OH)4](ClO4)4·4MeCN·0.5MeOH (1). Complex 1 crystallizes in triclinic, space group P1 with a=12.068(12), b=12.567(12), c=16.279(16)Å, α=105.694(12), β=93.631(13), γ=112.017(11)°, V=2166(4)Å3, Z=1, μ=1.651 mm-1, Dc=1.599 Mg/m3, T=296(2) K, C74.5H79.5N14O24.5Cl4Cu6, Mr=2086.12, F(000)=1062.5, S=1.061, R=0.0521 and wR=0.1270. In the cation of complex 1, the six copper cores are arranged into a two-parallel three-site strings configuration with each metal exhibits a slightly distorted square-pyramidal geometry, resulting from the connection of donor pyridinyl nitrogen and phenolate oxygen atoms in ligand H2L, and/or the oxygen donors in hydroxyl groups. In addition, magnetic susceptibility measurements revealed complex 1 displayed antiferromagnetic coupling.
2015, 34(4): 576-584
doi: 10.14102/j.cnki.0254-5861.2011-0566
Abstract:
Two new coordination polymers [Co(oba)(mbix)]2n·nH2O (1) and [Mn(Hoba)2(H2O)2]n (2) (H2oba=4,4'-oxydibenzoic acid, mbix=1,3-bis(imidazol-1-ylmethyl)benzene) have been successfully synthesized under hydrothermal conditions. Their structures have been determined by elemental analyses, IR spectroscopy, UV and single-crystal X-ray diffraction analysis. The intermolecular hydrogen bonding and π-π stacking interactions extend the complexes into a 3D supramolecular structure.
Two new coordination polymers [Co(oba)(mbix)]2n·nH2O (1) and [Mn(Hoba)2(H2O)2]n (2) (H2oba=4,4'-oxydibenzoic acid, mbix=1,3-bis(imidazol-1-ylmethyl)benzene) have been successfully synthesized under hydrothermal conditions. Their structures have been determined by elemental analyses, IR spectroscopy, UV and single-crystal X-ray diffraction analysis. The intermolecular hydrogen bonding and π-π stacking interactions extend the complexes into a 3D supramolecular structure.
2015, 34(4): 585-593
doi: 10.14102/j.cnki.0254-5861.2011-0555
Abstract:
By using solvothermal method, two new main group metal coordination polymers based on 2,5-furandicarboxylic acid (H2FDA) ligand, [Sr2(FDA)2(H2O)5]n (1) and [Ba4(FDA)4(H2O)10]n (2), were produced and characterized by single-crystal X-ray diffraction analyses, elemental analyses, IR, and powder X-ray diffraction. Compound 1 crystallizes in monoclinic, space group C2/c with a=13.454(3), b=13.426(3), c=20.166(4)Å, β=107.06(3)°, V=3482.4(13)Å3, Dc=2.188 g/cm3, C12H14Sr2O15, Mr=573.47, F(000)=2256, μ(MoKα)=6.21 mm-1, Z=8, R=0.0522 and wR=0.1229 for 2493 observed reflections (I>2σ(I)), and R=0.0689 and wR=0.1324 for all data. Compound 2 crystallizes in triclinic, space group P1 with a=6.8382(14), b=10.932(2), c=25.571(5)Å, α=94.64(3), β=95.41(3), γ=107.83(3)°, V=1799.4(6)Å3, Dc=2.484 g/cm3, C24H28Ba4O30, Mr=1345.82, F(000)=1272, μ(MoKα)=4.43 mm-1, Z=2, R=0.0485 and wR=0.0906 for 5020 observed reflections (I>2σ(I)), and R=0.0706 and wR=0.0991 for all data. In 1, the trinuclear clusters Sr3 are connected with adjacent four clusters by a carboxylate group to produce a two-dimensional (2D) sheet, which is extended by a FDA-based pillar into a 3D framework. In 2, neighbouring trinuclear clusters Ba3 are linked through two -O-C-O- of FDA2- ligands to form one-dimensional (1D) chains, which are connected by a FDA-based pillar to construct a 2D framework. The thermal stabilities of 1 and 2 are also investigated.
By using solvothermal method, two new main group metal coordination polymers based on 2,5-furandicarboxylic acid (H2FDA) ligand, [Sr2(FDA)2(H2O)5]n (1) and [Ba4(FDA)4(H2O)10]n (2), were produced and characterized by single-crystal X-ray diffraction analyses, elemental analyses, IR, and powder X-ray diffraction. Compound 1 crystallizes in monoclinic, space group C2/c with a=13.454(3), b=13.426(3), c=20.166(4)Å, β=107.06(3)°, V=3482.4(13)Å3, Dc=2.188 g/cm3, C12H14Sr2O15, Mr=573.47, F(000)=2256, μ(MoKα)=6.21 mm-1, Z=8, R=0.0522 and wR=0.1229 for 2493 observed reflections (I>2σ(I)), and R=0.0689 and wR=0.1324 for all data. Compound 2 crystallizes in triclinic, space group P1 with a=6.8382(14), b=10.932(2), c=25.571(5)Å, α=94.64(3), β=95.41(3), γ=107.83(3)°, V=1799.4(6)Å3, Dc=2.484 g/cm3, C24H28Ba4O30, Mr=1345.82, F(000)=1272, μ(MoKα)=4.43 mm-1, Z=2, R=0.0485 and wR=0.0906 for 5020 observed reflections (I>2σ(I)), and R=0.0706 and wR=0.0991 for all data. In 1, the trinuclear clusters Sr3 are connected with adjacent four clusters by a carboxylate group to produce a two-dimensional (2D) sheet, which is extended by a FDA-based pillar into a 3D framework. In 2, neighbouring trinuclear clusters Ba3 are linked through two -O-C-O- of FDA2- ligands to form one-dimensional (1D) chains, which are connected by a FDA-based pillar to construct a 2D framework. The thermal stabilities of 1 and 2 are also investigated.
2015, 34(4): 594-598
doi: 10.14102/j.cnki.0254-5861.2011-0552
Abstract:
A new copper(I)-lead(Ⅱ) oxyhalide, CuPb2(OH)2Cl3, has been prepared by hydrothermal reaction and structurally characterized by single-crystal X-ray analysis. The compound crystallizes in tetragonal, space group I4(1)/acd with a=b=13.77(1), c=15.38(1)Å, V=2916.2(2), Z=4, Mr=618.29, Dc=5.633 g/cm3, μ=49.97(2) mm-1, F(000)=4192, the final R=0.0204 and wR=0.0452 for 757 observed reflections with I>2σ(I). The structure of CuPb2(OH)2Cl3 contains one-dimensional helical chains built by CuCl4 tetrahedra with corner-sharing along the c-axis, in which the Pb2+ and OH-ions are located at the voids between chains. Optical reflectance spectrum measurements indicate that it is a semiconductor with a band-gap of 3.23 eV.
A new copper(I)-lead(Ⅱ) oxyhalide, CuPb2(OH)2Cl3, has been prepared by hydrothermal reaction and structurally characterized by single-crystal X-ray analysis. The compound crystallizes in tetragonal, space group I4(1)/acd with a=b=13.77(1), c=15.38(1)Å, V=2916.2(2), Z=4, Mr=618.29, Dc=5.633 g/cm3, μ=49.97(2) mm-1, F(000)=4192, the final R=0.0204 and wR=0.0452 for 757 observed reflections with I>2σ(I). The structure of CuPb2(OH)2Cl3 contains one-dimensional helical chains built by CuCl4 tetrahedra with corner-sharing along the c-axis, in which the Pb2+ and OH-ions are located at the voids between chains. Optical reflectance spectrum measurements indicate that it is a semiconductor with a band-gap of 3.23 eV.
2015, 34(4): 599-605
doi: 10.14102/j.cnki.0254-5861.2011-0542
Abstract:
A new Co(Ⅱ) metal-organic coordination polymer based on flexible bis(imidazole) and aromatic dicarboxylate co-ligands, namely [Co(bix)(nph)]n (H2nph=3-nitrophthalic acid, bix=1,4-bis(imidazole-1-ylmethyl)benzene), has been hydrothermally synthesized and characterized by elemental analyses, TG, IR spectroscopy and single-crystal X-ray diffraction. It crystallizes in the triclinic space group P1 with a=9.3767(14), b=10.1451(15), c=12.1488(17)Å, α=102.6450(10), β=108.856(2), γ=98.807(2)°, V=1035.3(3)Å3, Z=2, C22H17CoN5O6, Mr=506.34, Dc=1.624 g/cm3, μ=0.882 mm-1 and F(000)=518. In the complex, the nph2- ligands connect neighbouring cobalt atoms to form binuclear [Co(nph)]2 subunits, which are linked by pairs of bix ligands to form a 2D honeycomb-like (6,3) network. In addition, the compound is further extended into a 3D supramolecular architecture by π…π stacking interactions. Moreover, the luminescence and catalytic properties of the complex are investigated.
A new Co(Ⅱ) metal-organic coordination polymer based on flexible bis(imidazole) and aromatic dicarboxylate co-ligands, namely [Co(bix)(nph)]n (H2nph=3-nitrophthalic acid, bix=1,4-bis(imidazole-1-ylmethyl)benzene), has been hydrothermally synthesized and characterized by elemental analyses, TG, IR spectroscopy and single-crystal X-ray diffraction. It crystallizes in the triclinic space group P1 with a=9.3767(14), b=10.1451(15), c=12.1488(17)Å, α=102.6450(10), β=108.856(2), γ=98.807(2)°, V=1035.3(3)Å3, Z=2, C22H17CoN5O6, Mr=506.34, Dc=1.624 g/cm3, μ=0.882 mm-1 and F(000)=518. In the complex, the nph2- ligands connect neighbouring cobalt atoms to form binuclear [Co(nph)]2 subunits, which are linked by pairs of bix ligands to form a 2D honeycomb-like (6,3) network. In addition, the compound is further extended into a 3D supramolecular architecture by π…π stacking interactions. Moreover, the luminescence and catalytic properties of the complex are investigated.
2015, 34(4): 606-610
doi: 10.14102/j.cnki.0254-5861.2011-0470
Abstract:
In this work, a new Cd(Ⅱ) dimeric compound, [Cd(Cl)2(L)(H2O)]2 (1, L=2-(4-fluorophenyl)-1H-imidazo[4,5-f][1,10]phenanthroline), has been achieved under hydrothermal conditions. The structure of compound 1 was determined by single-crystal X-ray diffraction. Compound 1 crystallizes in monoclinic, space group P21/c with a=8.944(2), b=18.781(5), c=10.904(3)Å, β=91.392(4)°, V=1831.2(8)Å3, Z=2, CH26Cd2F2Cl4C14N8O2, Mr=1031.27, Dc=1.870 g/cm3, F(000)=1016, μ(MoKa)=1.513 mm-1, R=0.0532 and wR=0.1407. Each Cd(Ⅱ) atom is in an octahedral coordination sphere, completed by two nitrogen atoms from one L ligand, two chlorine anions, and one water oxygen atom. Two chlorine anions bridge two Cd(Ⅱ) atoms to give a dimer [Cd(Cl)2(L)(H2O)]2. Adjacent dimers are stacked by one type of π-π interactions among L ligands to generate a 1D supramolecular chain. Further, the 1D supramolecular chains are stacked by another type of π-π interactions among L ligands to give a 2D supramolecular layer. Finally, the luminescent property of 1 has been studied in solid state at room temperature.
In this work, a new Cd(Ⅱ) dimeric compound, [Cd(Cl)2(L)(H2O)]2 (1, L=2-(4-fluorophenyl)-1H-imidazo[4,5-f][1,10]phenanthroline), has been achieved under hydrothermal conditions. The structure of compound 1 was determined by single-crystal X-ray diffraction. Compound 1 crystallizes in monoclinic, space group P21/c with a=8.944(2), b=18.781(5), c=10.904(3)Å, β=91.392(4)°, V=1831.2(8)Å3, Z=2, C
2015, 34(4): 611-618
doi: 10.14102/j.cnki.0254-5861.2011-0541
Abstract:
A novel Cd(Ⅱ) coordination polymer, [CdCl(Hpc)H2O]n (1, H2pc=1H-pyrazole-3-carboxylic acid), was synthesized by the reaction of CdCl2·2.5H2O with H2pc, and structurally characterized by IR spectrum, UV-Vis spectrum, elemental analysis, single-crystal X-ray diffraction, as well as thermal analysis. Compound 1 crystallizes in monoclinic, P21/n space group with a=7.0304(3), b=10.3047(3), c=10.6446(4)Å, β=107.174(4)°, V=736.78(5)Å3, Z=4, C4H5CdClN2O3, Mr=276.95, Dc=2.497 g/cm3, F(000)=528.0, μ=3.281 mm-1, R=0.0169 and wR=0.0387. The central metals adopt distorted octahedral geometry. Carboxyl groups of the ligand connect Cd(Ⅱ) into a one-dimensional chain, which further constructs a two-dimensional network by halogen bridging. Such two-dimensional structures are finally connected into a three-dimensional supramolecular architecture due to the hydrogen bonds and intermolecular π-π interactions. In addition, complex 1 has high thermal stability.
A novel Cd(Ⅱ) coordination polymer, [CdCl(Hpc)H2O]n (1, H2pc=1H-pyrazole-3-carboxylic acid), was synthesized by the reaction of CdCl2·2.5H2O with H2pc, and structurally characterized by IR spectrum, UV-Vis spectrum, elemental analysis, single-crystal X-ray diffraction, as well as thermal analysis. Compound 1 crystallizes in monoclinic, P21/n space group with a=7.0304(3), b=10.3047(3), c=10.6446(4)Å, β=107.174(4)°, V=736.78(5)Å3, Z=4, C4H5CdClN2O3, Mr=276.95, Dc=2.497 g/cm3, F(000)=528.0, μ=3.281 mm-1, R=0.0169 and wR=0.0387. The central metals adopt distorted octahedral geometry. Carboxyl groups of the ligand connect Cd(Ⅱ) into a one-dimensional chain, which further constructs a two-dimensional network by halogen bridging. Such two-dimensional structures are finally connected into a three-dimensional supramolecular architecture due to the hydrogen bonds and intermolecular π-π interactions. In addition, complex 1 has high thermal stability.
2015, 34(4): 619-623
doi: 10.14102/j.cnki.0254-5861.2011-0533
Abstract:
ZnC6H8N2O5·H2O (NCGZn) has been synthesized, and its functional groups present in the title compound were confirmed by elemental analysis, TG and IR spectral studies. Meanwhile, the crystal of NCGZn was obtained by slow evaporation of a saturated aqueous solution at room temperature and confirmed by single-crystal X-ray diffraction analysis. It crystallizes in triclinic, space group P21 with a=5.03220(1), b=13.3747(4), c=12.9944(4)Å, β=92.987(2)°, V=873.39(4)Å3, Z=2, C12H20N4O12Zn2, Mr=543.10, Dc=2.065 g/cm3, F(000)=552, μ(MoKa)=2.826 mm-1, R=0.0422 and wR=0.1142. In NCGZn, Zn1 and the symmetry formed Zn1 ions are connected by five atoms from four NCG-2H anions and a water molecule. A NCG ligand has two carboxylate groups, one connecting a Zn ion, and the other bridgiong two Zn ions. The NCG ligand bridges four Zn ions through the amino group and two carboxylate groups with a water molecule to yield a 3D coordination polymer structure with hydrogen bonds.
ZnC6H8N2O5·H2O (NCGZn) has been synthesized, and its functional groups present in the title compound were confirmed by elemental analysis, TG and IR spectral studies. Meanwhile, the crystal of NCGZn was obtained by slow evaporation of a saturated aqueous solution at room temperature and confirmed by single-crystal X-ray diffraction analysis. It crystallizes in triclinic, space group P21 with a=5.03220(1), b=13.3747(4), c=12.9944(4)Å, β=92.987(2)°, V=873.39(4)Å3, Z=2, C12H20N4O12Zn2, Mr=543.10, Dc=2.065 g/cm3, F(000)=552, μ(MoKa)=2.826 mm-1, R=0.0422 and wR=0.1142. In NCGZn, Zn1 and the symmetry formed Zn1 ions are connected by five atoms from four NCG-2H anions and a water molecule. A NCG ligand has two carboxylate groups, one connecting a Zn ion, and the other bridgiong two Zn ions. The NCG ligand bridges four Zn ions through the amino group and two carboxylate groups with a water molecule to yield a 3D coordination polymer structure with hydrogen bonds.
2015, 34(4): 624-631
doi: 10.14102/j.cnki.0254-5861.2011-0546
Abstract:
Via the first principles calculations, we predict that Cu doped graphene oxide (GO) is a much better nanocatalyst in terms of activity and feasibility. The high activity of Cu doped graphene oxides may be attributed to the charge transfer between the GO and Cu atom, resulting in an activated Cu atom. In the ER mechanism, the CO molecules directly react with the activated O2, then forming a metastable carbonate-like intermediate state (OOCO). The reaction may proceed via two reaction paths of OOCO→CO2+O and CO+OOCO→2CO2, respectively. The calculated results show that the latter path is relatively more thermodynamically favorable with a modest energy barrier, so it should be more preferred. We expect our theoretical predictions to open a new avenue to fabricate carbon-based catalysts for CO oxidation with lower cost and higher activity.
Via the first principles calculations, we predict that Cu doped graphene oxide (GO) is a much better nanocatalyst in terms of activity and feasibility. The high activity of Cu doped graphene oxides may be attributed to the charge transfer between the GO and Cu atom, resulting in an activated Cu atom. In the ER mechanism, the CO molecules directly react with the activated O2, then forming a metastable carbonate-like intermediate state (OOCO). The reaction may proceed via two reaction paths of OOCO→CO2+O and CO+OOCO→2CO2, respectively. The calculated results show that the latter path is relatively more thermodynamically favorable with a modest energy barrier, so it should be more preferred. We expect our theoretical predictions to open a new avenue to fabricate carbon-based catalysts for CO oxidation with lower cost and higher activity.
