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2014 Volume 33 Issue 4
2014, 33(4): 505-512
Abstract:
8-Oxoguanine (8-oxoG), a critical mutagenic DNA lesion induced by reactive oxy-gen species, gives rise to a G·C→T·A transversion during replication and thereby must be repaired. The effects of explicit and implicit solvent molecules on the hydrolysis cleavage of N-Glycosidic bond in 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxo-dG) have been systematically clarified in the present work based upon two types of computational models. Detailed potential energy surface (PES) scans and full unconstraint optimizations for all the representative points on PESs were carried out at the B3LYP/6-31+G(d) level of theory. The effect of implicit solvent was tested by single-point calculation at the SCRF/IEF-PCM model. The results illustrate that the direct hydrolysis model involving one explicit water molecule can't provide a complete depiction of the hydrolysis process of 8-oxo-dG, attributed to the insufficiency of nucleophile activation and leaving group stabilization. The expansion hydrolysis model involving four explicit water molecules, however, facilitates discrete proton transfer and therefore produces smooth reaction surfaces for both the dissociative (SN1) and concerted (SN2) pathways. The presence of the implicit solvent substantially lowers all activation energies and the SN1 process is more favorable than the SN2 process. The data and insights present here agree well with the experimental results and have given out a baseline for the enzymatic deglycosylation reaction of 8-oxo-dG.
8-Oxoguanine (8-oxoG), a critical mutagenic DNA lesion induced by reactive oxy-gen species, gives rise to a G·C→T·A transversion during replication and thereby must be repaired. The effects of explicit and implicit solvent molecules on the hydrolysis cleavage of N-Glycosidic bond in 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxo-dG) have been systematically clarified in the present work based upon two types of computational models. Detailed potential energy surface (PES) scans and full unconstraint optimizations for all the representative points on PESs were carried out at the B3LYP/6-31+G(d) level of theory. The effect of implicit solvent was tested by single-point calculation at the SCRF/IEF-PCM model. The results illustrate that the direct hydrolysis model involving one explicit water molecule can't provide a complete depiction of the hydrolysis process of 8-oxo-dG, attributed to the insufficiency of nucleophile activation and leaving group stabilization. The expansion hydrolysis model involving four explicit water molecules, however, facilitates discrete proton transfer and therefore produces smooth reaction surfaces for both the dissociative (SN1) and concerted (SN2) pathways. The presence of the implicit solvent substantially lowers all activation energies and the SN1 process is more favorable than the SN2 process. The data and insights present here agree well with the experimental results and have given out a baseline for the enzymatic deglycosylation reaction of 8-oxo-dG.
2014, 33(4): 513-518
Abstract:
Single atom chemically doped graphene has been theoretically studied by density functional theory. The largest band gap, 0.62 eV, appears in arsenic atom doped graphene, then 0.60 eV comes by the tin atom, whose deformations can neither be ignored. It is also found that oxygen and iron single atom embedded graphene can open band gap by 0.52 and 0.54 eV, respectively. Moreover, doping O atom shows little distortion and high stability by charge redistribution. The band gap of Fe doped graphene is opened by orbital hybridization. The other heteroatom doped results are a little inferior to them.
Single atom chemically doped graphene has been theoretically studied by density functional theory. The largest band gap, 0.62 eV, appears in arsenic atom doped graphene, then 0.60 eV comes by the tin atom, whose deformations can neither be ignored. It is also found that oxygen and iron single atom embedded graphene can open band gap by 0.52 and 0.54 eV, respectively. Moreover, doping O atom shows little distortion and high stability by charge redistribution. The band gap of Fe doped graphene is opened by orbital hybridization. The other heteroatom doped results are a little inferior to them.
2014, 33(4): 519-527
Abstract:
The electronic structures and optical properties of Ⅱ-Ⅲ2-VI4 (Ⅱ=Zn, Cd; Ⅲ=In; VI=Se, Te) compounds are studied by the density functional theory (DFT) using the Vienna ab initio simulation package (VASP). Geometrical optimization of the unit cell is in good agreement with the experimental data. Our calculations show that the valence band maximum (VBM) and conduction band minimum (CBM) are located at G resulting in a direct energy gap. The optical properties are analyzed, and the independent second harmonic generation (SHG) coefficients are determined. By an analysis of the band structure, we can get that SHG response of the system can be attributed to the transitions from the bands near the top of valence band that are derived from the Se/Te p states to the unoccupied bands contributed by the p states of In atoms.
The electronic structures and optical properties of Ⅱ-Ⅲ2-VI4 (Ⅱ=Zn, Cd; Ⅲ=In; VI=Se, Te) compounds are studied by the density functional theory (DFT) using the Vienna ab initio simulation package (VASP). Geometrical optimization of the unit cell is in good agreement with the experimental data. Our calculations show that the valence band maximum (VBM) and conduction band minimum (CBM) are located at G resulting in a direct energy gap. The optical properties are analyzed, and the independent second harmonic generation (SHG) coefficients are determined. By an analysis of the band structure, we can get that SHG response of the system can be attributed to the transitions from the bands near the top of valence band that are derived from the Se/Te p states to the unoccupied bands contributed by the p states of In atoms.
Syntheses, Crystal Structures and Antibacterial Activities of Two Heterocyclic Schiff Base Compounds
2014, 33(4): 528-534
Abstract:
Two heterocyclic Schiff bases were synthesized via the condensation reactions of primary amines with carbonyl compounds. 2-[(4-pyridylmethylene)-amino] phenol (compound 1) was synthesized by the interaction of 4-pyridinecarboxaldehyde with o-aminophenol in ethanol solvent; N,N'-bis(3-(furan-2-yl)allylidene)benzene-1,4-diamin (compound 2) was synthesized by the interaction of 3-(2-furyl)acrolein with p-phenylenediamine in ethanol medium. The compounds were characterized by elemental analysis, IR, MS and single-crystal X-ray diffraction. Compound 1 (C12H10N2O) crystallizes in the monoclinic system, space group P21/c with a=7.0771(7), b=7.2820(7), c=19.849(2), β=96.3390(10)°, V=1016.66(17) Å3, Z=4, Mr=198.22, Dc=1.295 g/cm3, F(000)=416, GOOF=1.060, μ=0.085 mm-1, the final R=0.0371 and wR=0.0929 for 1497 observed reflections with I>2σ(I). Compound 2 (C20H16N2O2) crystallizes in the orthorhombic system, space group Fdd2 with a=26.344(15), b=48.50(3), c=5.293(3), V=6764(7) Å3, Z=16, Mr=316.35, Dc=1.243 g/cm3, F(000)=2656, GOOF=1.043, μ=0.081 mm-1, the final R=0.0526 and wR=0.1267 for 2059 observed reflections with I>2σ(I). 1 and 2 molecules are connected through hydrogen bonds to generate a 2D network and a 1D chain structure, respectively. The preliminary antibacterial activity results showed that the title compounds display excellent antibacterial activities to Escherichia coli, Staphylococcus aureus and Bacillus subtilis.
Two heterocyclic Schiff bases were synthesized via the condensation reactions of primary amines with carbonyl compounds. 2-[(4-pyridylmethylene)-amino] phenol (compound 1) was synthesized by the interaction of 4-pyridinecarboxaldehyde with o-aminophenol in ethanol solvent; N,N'-bis(3-(furan-2-yl)allylidene)benzene-1,4-diamin (compound 2) was synthesized by the interaction of 3-(2-furyl)acrolein with p-phenylenediamine in ethanol medium. The compounds were characterized by elemental analysis, IR, MS and single-crystal X-ray diffraction. Compound 1 (C12H10N2O) crystallizes in the monoclinic system, space group P21/c with a=7.0771(7), b=7.2820(7), c=19.849(2), β=96.3390(10)°, V=1016.66(17) Å3, Z=4, Mr=198.22, Dc=1.295 g/cm3, F(000)=416, GOOF=1.060, μ=0.085 mm-1, the final R=0.0371 and wR=0.0929 for 1497 observed reflections with I>2σ(I). Compound 2 (C20H16N2O2) crystallizes in the orthorhombic system, space group Fdd2 with a=26.344(15), b=48.50(3), c=5.293(3), V=6764(7) Å3, Z=16, Mr=316.35, Dc=1.243 g/cm3, F(000)=2656, GOOF=1.043, μ=0.081 mm-1, the final R=0.0526 and wR=0.1267 for 2059 observed reflections with I>2σ(I). 1 and 2 molecules are connected through hydrogen bonds to generate a 2D network and a 1D chain structure, respectively. The preliminary antibacterial activity results showed that the title compounds display excellent antibacterial activities to Escherichia coli, Staphylococcus aureus and Bacillus subtilis.
2014, 33(4): 535-543
Abstract:
The title compound diethyl 1,4-dihydro-2,6-dimethyl-4-(4-methyl-1,2,3-thiadiazol-5-yl) pyridine-3,5-dicarboxylate (C16H21N3O4S, Mr=351.42) was prepared by the Hantszch reaction with 4-methyl-1,2,3-thiadiazole-5-formaldehyde, ethyl acetoacetate and ammonium acetate in the presence of aluminum chloride in alcohol, and its structure was characterized by IR spectra, 1H-NMR, EA, and single-crystal X-ray diffraction. The crystal of the title compound belongs to monoclinic system, space group P21/n with a=11.300(2), b=12.771(3), c=12.826(3) Å, β=96.55(3)°, V=1839.0(6) Å3, Z=4, Dc=1.296 g/cm3, μ(MoKa)=0.71073 mm-1, F(000)=744, R=0.0981 and wR=0.1994. X-ray diffraction result shows that the torsion angles of N(1)-C(2)-C(3)-C(4) and C(2)-C(3)-C(4)-C(8) are 178.9(3)° and -130.3(3)°, respectively. All rings in the title compound are non-planar. The bioassay results indicate that the title compound has good fungicidal activity, good antivirus activity against tobacco mosaic virus and certain extent of insecticidal activity against Mythimna separata.
The title compound diethyl 1,4-dihydro-2,6-dimethyl-4-(4-methyl-1,2,3-thiadiazol-5-yl) pyridine-3,5-dicarboxylate (C16H21N3O4S, Mr=351.42) was prepared by the Hantszch reaction with 4-methyl-1,2,3-thiadiazole-5-formaldehyde, ethyl acetoacetate and ammonium acetate in the presence of aluminum chloride in alcohol, and its structure was characterized by IR spectra, 1H-NMR, EA, and single-crystal X-ray diffraction. The crystal of the title compound belongs to monoclinic system, space group P21/n with a=11.300(2), b=12.771(3), c=12.826(3) Å, β=96.55(3)°, V=1839.0(6) Å3, Z=4, Dc=1.296 g/cm3, μ(MoKa)=0.71073 mm-1, F(000)=744, R=0.0981 and wR=0.1994. X-ray diffraction result shows that the torsion angles of N(1)-C(2)-C(3)-C(4) and C(2)-C(3)-C(4)-C(8) are 178.9(3)° and -130.3(3)°, respectively. All rings in the title compound are non-planar. The bioassay results indicate that the title compound has good fungicidal activity, good antivirus activity against tobacco mosaic virus and certain extent of insecticidal activity against Mythimna separata.
2014, 33(4): 544-548
Abstract:
A new glycoluril derivative 2 has been synthesized and characterized by single- crystal X-ray diffraction. It crystallizes in triclinic, space group P1 with a=13.128(7), b=13.245(7), c=14.016(8) Å, α=98.805(10), β=102.036(9), γ=101.470(10)°, V=2287(2) Å3, Z=2, C54H38N8O6·H2O, Mr=912.94, F(000)=952, T=298(2) K, Dc=1.326 g/cm3 and μ=0.090 mm-1. Due to the intermolecular C-H…O interactions, two monomeric molecular clips dimerize as a dimeric building block in the crystalline state. Those building blocks form tape-like supramolecular polymers driven by intermolecular C-H…N interactions and water molecules which stabilized in the packing structure served as hydrogen-bonding donors.
A new glycoluril derivative 2 has been synthesized and characterized by single- crystal X-ray diffraction. It crystallizes in triclinic, space group P1 with a=13.128(7), b=13.245(7), c=14.016(8) Å, α=98.805(10), β=102.036(9), γ=101.470(10)°, V=2287(2) Å3, Z=2, C54H38N8O6·H2O, Mr=912.94, F(000)=952, T=298(2) K, Dc=1.326 g/cm3 and μ=0.090 mm-1. Due to the intermolecular C-H…O interactions, two monomeric molecular clips dimerize as a dimeric building block in the crystalline state. Those building blocks form tape-like supramolecular polymers driven by intermolecular C-H…N interactions and water molecules which stabilized in the packing structure served as hydrogen-bonding donors.
2014, 33(4): 549-556
Abstract:
A new bismuth(Ⅲ) iodide inorganic/organic hybrid containing larger heterocyclic conjugated organic ligand, [(dppz)2Bi2I6]·2DMF (1) (dppz=dipyrido[3,2-a:2',3'-c]phenazine), has been synthesized by solution process and structurally determined by X-ray diffraction method. 1 crystallizes in triclinic, space group P1 with Mr=1844.08, a=9.215(5), b=11.488(6), c=12.424(9) Å, α=106.66(2), β=90.84(2), γ=92.34(2)°, V=1258.5(13) Å3, Z=1, Dc=2.433 g/cm3, F(000)=830, μ(MoKα)=10.702 mm-1, the final R=0.0834 and wR=0.1947 for 2749 observed reflections with I>2σ(I). 1 consists of a dimeric structure [(dppz)2Bi2I6], in which two [(dppz)BiI3] fragments are bridged by a pair of iodine atoms. Hydrogen bonds and π…π stacking interactions contribute to the structural extension and stabilization. Experimental band gap of about 2.13 eV indicates its semiconductor nature. The optical absorption spectrum and electronic structure were also discussed.
A new bismuth(Ⅲ) iodide inorganic/organic hybrid containing larger heterocyclic conjugated organic ligand, [(dppz)2Bi2I6]·2DMF (1) (dppz=dipyrido[3,2-a:2',3'-c]phenazine), has been synthesized by solution process and structurally determined by X-ray diffraction method. 1 crystallizes in triclinic, space group P1 with Mr=1844.08, a=9.215(5), b=11.488(6), c=12.424(9) Å, α=106.66(2), β=90.84(2), γ=92.34(2)°, V=1258.5(13) Å3, Z=1, Dc=2.433 g/cm3, F(000)=830, μ(MoKα)=10.702 mm-1, the final R=0.0834 and wR=0.1947 for 2749 observed reflections with I>2σ(I). 1 consists of a dimeric structure [(dppz)2Bi2I6], in which two [(dppz)BiI3] fragments are bridged by a pair of iodine atoms. Hydrogen bonds and π…π stacking interactions contribute to the structural extension and stabilization. Experimental band gap of about 2.13 eV indicates its semiconductor nature. The optical absorption spectrum and electronic structure were also discussed.
2014, 33(4): 557-562
Abstract:
A new complex, [Ni2(L)4(H2O)8](1, L1=4-(1H-imidazol-4-yl)benzoic acid), has been hydrothermally prepared and characterized by single-crystal X-ray diffraction, IR spectroscopy, elemental analysis and PXRD. Complex 1 crystallizes in monoclinic, space group P21/c with a=22.281(2), b=7.3959(7), c=24.978(3) Å, β=90.876(10), V=4115.6(7) Å3, Z=8, C20H22N4O8Ni, Mr=505.13, Dc=1.630 g/cm3, μ=1.001 mm-1, S=1.080, F(000)=2096, the final R=0.452 and wR=0.1152 for 9380 observed reflections (I>2σ(I)). The result of X-ray diffraction analysis revealed three different kinds of Ni(Ⅱ) centre mononuclear molecules in the asymmetric unit. The independent mononuclear units are bridged to form a three-dimensional supramolecular polymer by extensive hydrogen bonds and C-H…π non-covalent bonding interactions.
A new complex, [Ni2(L)4(H2O)8](1, L1=4-(1H-imidazol-4-yl)benzoic acid), has been hydrothermally prepared and characterized by single-crystal X-ray diffraction, IR spectroscopy, elemental analysis and PXRD. Complex 1 crystallizes in monoclinic, space group P21/c with a=22.281(2), b=7.3959(7), c=24.978(3) Å, β=90.876(10), V=4115.6(7) Å3, Z=8, C20H22N4O8Ni, Mr=505.13, Dc=1.630 g/cm3, μ=1.001 mm-1, S=1.080, F(000)=2096, the final R=0.452 and wR=0.1152 for 9380 observed reflections (I>2σ(I)). The result of X-ray diffraction analysis revealed three different kinds of Ni(Ⅱ) centre mononuclear molecules in the asymmetric unit. The independent mononuclear units are bridged to form a three-dimensional supramolecular polymer by extensive hydrogen bonds and C-H…π non-covalent bonding interactions.
2014, 33(4): 563-568
Abstract:
A new coordination polymer [Ni(L)(m-bix)(H2O)]n (1, H2L=5-iodo-isophthalic acid, m-bix=1,3-bis(imidazol-1-ylmethyl)-benzene) has been synthesized by the hydrothermal method and characterized by IR, elemental analysis, powder XRD and single-crystal X-ray analysis. The crystal is of triclinic, space group P1 with a=9.1638(3), b=10.2319(3), c=13.2463(4) Å, α=80.1710(10), β=83.671(2), γ=70.3790(10)°, C22H19NiIN4O5, Mr=605.02, V=1150.85(6) Å3, Dc=1.746 g/cm3, F(000)=600, μ=2.225 mm-1, S=1.045 and Z=2. The final R=0.0388 and wR=0.1257 for 5089 observed reflections with I>2σ(I). In the title complex, the M and P layers are arranged alternately to give a double-layer structure by the symmetry related hydrogen bonds, and these double-layers are further joined together to achieve a 2D supramolecular architecture through I…π interaction involving iodine atoms and imidazole rings. The thermal stability of the title complex was studied by thermal gravimetric (TG) and differential thermal analysis (DTA).
A new coordination polymer [Ni(L)(m-bix)(H2O)]n (1, H2L=5-iodo-isophthalic acid, m-bix=1,3-bis(imidazol-1-ylmethyl)-benzene) has been synthesized by the hydrothermal method and characterized by IR, elemental analysis, powder XRD and single-crystal X-ray analysis. The crystal is of triclinic, space group P1 with a=9.1638(3), b=10.2319(3), c=13.2463(4) Å, α=80.1710(10), β=83.671(2), γ=70.3790(10)°, C22H19NiIN4O5, Mr=605.02, V=1150.85(6) Å3, Dc=1.746 g/cm3, F(000)=600, μ=2.225 mm-1, S=1.045 and Z=2. The final R=0.0388 and wR=0.1257 for 5089 observed reflections with I>2σ(I). In the title complex, the M and P layers are arranged alternately to give a double-layer structure by the symmetry related hydrogen bonds, and these double-layers are further joined together to achieve a 2D supramolecular architecture through I…π interaction involving iodine atoms and imidazole rings. The thermal stability of the title complex was studied by thermal gravimetric (TG) and differential thermal analysis (DTA).
2014, 33(4): 569-578
Abstract:
Hydrothermal reactions of three aromatic polycarboxylic acids and the transitional metal cations in the presence of phen and 1,4-bib afford three new coordination polymers: [Cd2(bpp)1.5(Hbpp)(phen)2]n (1), [Mn3(Htptc)2(phen)2(H2O)2]n (2), and {[Cu(btc)0.5(1,4-bib)]·2H2O}n (3) (H2bpp=2,6-bis(4'-carboxyphenyl)-4-phenylpyridine, H4tptc=terphenyl-2,5,2',5'-tetracar-boxylic acid, H4btc=biphenyl-2,2',4,4'-tetracarboxylic acid, phen=1,10-phenanthroline, and 1,4-bib=1,4-bis(1H-imidazol-1-yl)benzene). Their structures have been determined by single-crystal X-ray diffraction analyses, elemental analyses, IR spectra, and powder X-ray diffraction (PXRD) analyses. In compound 1, the CdⅡ cations are linked by bpp2- to form one ladder structure, based on which a 3D network is constructed with the help of non-covalent interactions. The topology of 2 is a 3D (3,4,5)-connected framework with the Point Schläfli symbol of (42.6)2(43.62.8)(45.64.8)2. Compound 3 shows an unprecedented 3D (4,4)-connected framework with the Point Schläfli symbol of (64.82)2(65.8). Moreover, the luminescent property of 1 has been investigated.
Hydrothermal reactions of three aromatic polycarboxylic acids and the transitional metal cations in the presence of phen and 1,4-bib afford three new coordination polymers: [Cd2(bpp)1.5(Hbpp)(phen)2]n (1), [Mn3(Htptc)2(phen)2(H2O)2]n (2), and {[Cu(btc)0.5(1,4-bib)]·2H2O}n (3) (H2bpp=2,6-bis(4'-carboxyphenyl)-4-phenylpyridine, H4tptc=terphenyl-2,5,2',5'-tetracar-boxylic acid, H4btc=biphenyl-2,2',4,4'-tetracarboxylic acid, phen=1,10-phenanthroline, and 1,4-bib=1,4-bis(1H-imidazol-1-yl)benzene). Their structures have been determined by single-crystal X-ray diffraction analyses, elemental analyses, IR spectra, and powder X-ray diffraction (PXRD) analyses. In compound 1, the CdⅡ cations are linked by bpp2- to form one ladder structure, based on which a 3D network is constructed with the help of non-covalent interactions. The topology of 2 is a 3D (3,4,5)-connected framework with the Point Schläfli symbol of (42.6)2(43.62.8)(45.64.8)2. Compound 3 shows an unprecedented 3D (4,4)-connected framework with the Point Schläfli symbol of (64.82)2(65.8). Moreover, the luminescent property of 1 has been investigated.
2014, 33(4): 579-584
Abstract:
A three-dimensional (3D) coordination polymer {[Co(bdc)(dpb)]·H2O}n (1) was prepared by solvothermal reaction of 1,3-dipyridyl benzene (dpb) with deprotonated 1,3-benzene-dicarboxylate (H2bdc), and was characterized by elemental analysis, IR spectroscopy, and X-ray single-crystal diffraction. It crystallizes in the monoclinic system, space group C2/c with a=15.478(6), b=12.865(5), c=24.091(10) Å, β=95.599(5)°, V=4774(3) Å3, C24H18CoN2O5, Mr=473.34, Dc=1.267 g/cm3, F(000)=1864.0, μ=0.748 mm-1 and Z=8. Each Co(Ⅱ) ion links three bdc2- anions to form an infinitely 1D ladder-shaped chain containing binuclear [(COO)Co]2 cluster, and dpb links adjacent 1D chains to form a 3D pcu framework. In addition, the UV-vis of 1 was also studied.
A three-dimensional (3D) coordination polymer {[Co(bdc)(dpb)]·H2O}n (1) was prepared by solvothermal reaction of 1,3-dipyridyl benzene (dpb) with deprotonated 1,3-benzene-dicarboxylate (H2bdc), and was characterized by elemental analysis, IR spectroscopy, and X-ray single-crystal diffraction. It crystallizes in the monoclinic system, space group C2/c with a=15.478(6), b=12.865(5), c=24.091(10) Å, β=95.599(5)°, V=4774(3) Å3, C24H18CoN2O5, Mr=473.34, Dc=1.267 g/cm3, F(000)=1864.0, μ=0.748 mm-1 and Z=8. Each Co(Ⅱ) ion links three bdc2- anions to form an infinitely 1D ladder-shaped chain containing binuclear [(COO)Co]2 cluster, and dpb links adjacent 1D chains to form a 3D pcu framework. In addition, the UV-vis of 1 was also studied.
2014, 33(4): 585-590
Abstract:
The novel alkaline metal complex Ca(BPDCH)2 (1, BPDCH2=2,2'-bipyri-dine-5,5'-dicarboxylic acid) has been synthesized by the hydrothermal reaction of Ca(NO3)2·4H2O with 2,2'-bipyridine-5,5'-dicarboxylic acid. The molecular and crystal structures of complex 1 have firstly been characterized by FTIR, elemental analysis, and X-ray single-crystal diffraction. The 3D MOF structure of complex 1 was interpreted by the versatile binding modes-the intermolecular hydrogen bonds and π-π stacking interactions of 2,2'-bipyridine-5,5'-dicarboxylic acid ligand. The analysis results show complex 1 belongs to a coordination polymer with 3D MOF structure. The results of thermogravimetric analysis and solubility demonstrate complex 1 is a thermostable compound and does not dissolve in water and traditional organic solvents.
The novel alkaline metal complex Ca(BPDCH)2 (1, BPDCH2=2,2'-bipyri-dine-5,5'-dicarboxylic acid) has been synthesized by the hydrothermal reaction of Ca(NO3)2·4H2O with 2,2'-bipyridine-5,5'-dicarboxylic acid. The molecular and crystal structures of complex 1 have firstly been characterized by FTIR, elemental analysis, and X-ray single-crystal diffraction. The 3D MOF structure of complex 1 was interpreted by the versatile binding modes-the intermolecular hydrogen bonds and π-π stacking interactions of 2,2'-bipyridine-5,5'-dicarboxylic acid ligand. The analysis results show complex 1 belongs to a coordination polymer with 3D MOF structure. The results of thermogravimetric analysis and solubility demonstrate complex 1 is a thermostable compound and does not dissolve in water and traditional organic solvents.
2014, 33(4): 591-596
Abstract:
A new Zn-citrate coordination complex {K[Zn(C6H5O7)(H2O)]}n (1) was synthesi-zed via hydrothermal reaction. In the crystal structure of complex 1, each citrate serves as the quadricdentate ligand coordinating to three Zn(Ⅱ) ions, forming a zigzag chain, and such chains are further connected into a 3D network by the K+ linkers. Crystal data for complex 1: triclinic, space group P1, a=7.3487(9), b=7.5397(6), c=9.6772(8) Å, α=76.894(8), β=68.260(10), γ=65.155(10)°, V=450.34(7) Å3 and Z=2. Other characterizations by elemental analysis, IR, TG and fluorescence were also described.
A new Zn-citrate coordination complex {K[Zn(C6H5O7)(H2O)]}n (1) was synthesi-zed via hydrothermal reaction. In the crystal structure of complex 1, each citrate serves as the quadricdentate ligand coordinating to three Zn(Ⅱ) ions, forming a zigzag chain, and such chains are further connected into a 3D network by the K+ linkers. Crystal data for complex 1: triclinic, space group P1, a=7.3487(9), b=7.5397(6), c=9.6772(8) Å, α=76.894(8), β=68.260(10), γ=65.155(10)°, V=450.34(7) Å3 and Z=2. Other characterizations by elemental analysis, IR, TG and fluorescence were also described.
2014, 33(4): 597-601
Abstract:
A new luminescent Zn(Ⅱ) compound, [Zn(pbdc)0.5(mtz)(DMPU)]n (1, H2pbdc=terephthalic acid, Hmtz=5-methyl-1H-tetrazole, DMPU=N,N'-dimethylpropyleneurea), has been urothermally synthesized and characterized by elemental analysis, IR, X-ray powder diffraction (PXRD) and single-crystal X-ray diffraction. The title compound crystallizes in orthorhombic Pbca space group with a=17.2649(5), b=10.4680(3), c=17.4457(7) Å, V=3152.94(18) Å3, C12H17N6O3Zn, Mr=358.71, Z=8, Dc=1.511 g/cm3, F(000)=1480, μ=1.579 mm-1, the final R=0.0379 and wR=0.0971 for 2785 observed reflections (I>2σ(I)). Single-crystal X-ray structural analysis reveals that compound 1 features a 2D undulated layer with a 3-connected hcb topology. Moreover, the luminescent properties of 1 have also been investigated in the solid-state at room temperature.
A new luminescent Zn(Ⅱ) compound, [Zn(pbdc)0.5(mtz)(DMPU)]n (1, H2pbdc=terephthalic acid, Hmtz=5-methyl-1H-tetrazole, DMPU=N,N'-dimethylpropyleneurea), has been urothermally synthesized and characterized by elemental analysis, IR, X-ray powder diffraction (PXRD) and single-crystal X-ray diffraction. The title compound crystallizes in orthorhombic Pbca space group with a=17.2649(5), b=10.4680(3), c=17.4457(7) Å, V=3152.94(18) Å3, C12H17N6O3Zn, Mr=358.71, Z=8, Dc=1.511 g/cm3, F(000)=1480, μ=1.579 mm-1, the final R=0.0379 and wR=0.0971 for 2785 observed reflections (I>2σ(I)). Single-crystal X-ray structural analysis reveals that compound 1 features a 2D undulated layer with a 3-connected hcb topology. Moreover, the luminescent properties of 1 have also been investigated in the solid-state at room temperature.
2014, 33(4): 602-606
Abstract:
One new complex has been produced under solvothermal reactions of tetrakis(4-pyridyloxymethylene)methane (TPOM) with glutaric acid (GA) in the presence of nitrates of cuprum in DMF/H2O (1:5, v/v), namely, {Cu2(TPOM)·GA)2}n. The complex crystallizes in the monoclinic system, space group P2/c with a=11.556(4), b=8.713(3), c=23.602(9) Å, V=2376.5(15) Å3, C35H36Cu2N4O12, Mr=831.76, Z=2, Dc=1.162 g·cm-3, F(000)=856, μ=0.947mm-1, R=0.0547 and wR=0.1718 (I>2σ(I)). This complex was characterized by elemental analysis, IR spectroscopy, and X-ray single-crystal diffraction. It is the first complex synthesized by coordinating with TPOM and catenulate aliphatic polycarboxylate acid ligands. The structural analyses show that the complex is a 2-fold interpenetrating 3D architecture.
One new complex has been produced under solvothermal reactions of tetrakis(4-pyridyloxymethylene)methane (TPOM) with glutaric acid (GA) in the presence of nitrates of cuprum in DMF/H2O (1:5, v/v), namely, {Cu2(TPOM)·GA)2}n. The complex crystallizes in the monoclinic system, space group P2/c with a=11.556(4), b=8.713(3), c=23.602(9) Å, V=2376.5(15) Å3, C35H36Cu2N4O12, Mr=831.76, Z=2, Dc=1.162 g·cm-3, F(000)=856, μ=0.947mm-1, R=0.0547 and wR=0.1718 (I>2σ(I)). This complex was characterized by elemental analysis, IR spectroscopy, and X-ray single-crystal diffraction. It is the first complex synthesized by coordinating with TPOM and catenulate aliphatic polycarboxylate acid ligands. The structural analyses show that the complex is a 2-fold interpenetrating 3D architecture.
2014, 33(4): 607-611
Abstract:
The title complex, C20H17N4Pd2Cl3·0.5CH3OH, crystallizes in the triclinic system, space group P1 with a=9.927(6), b=11.079(6), c=11.233(6) Å, α=73.970(12), β=85.738(16), γ=83.300(12)°, V=1178.1(11) Å3, Mr=648.55, Z=2, Dc=1.520 g/cm3, μ=1.884 mm-1, F(000)=634, the final R=0.0460 and wR=0.1280. This title compound was investigated for the catalytic behavior towards norbornene (NB) vinyl addition polymerization. And the complex exhibits good catalytic activity to catalyze norbornene polymerization using MAO as a cocatalyst.
The title complex, C20H17N4Pd2Cl3·0.5CH3OH, crystallizes in the triclinic system, space group P1 with a=9.927(6), b=11.079(6), c=11.233(6) Å, α=73.970(12), β=85.738(16), γ=83.300(12)°, V=1178.1(11) Å3, Mr=648.55, Z=2, Dc=1.520 g/cm3, μ=1.884 mm-1, F(000)=634, the final R=0.0460 and wR=0.1280. This title compound was investigated for the catalytic behavior towards norbornene (NB) vinyl addition polymerization. And the complex exhibits good catalytic activity to catalyze norbornene polymerization using MAO as a cocatalyst.
2014, 33(4): 612-618
Abstract:
Two new dicopper(Ⅱ) complexes [Cu2L(OAc)2](ClO4)·H2O (1) and [Cu2L(BPP)2]-(ClO4) (2) using an asymmetric dinucleating ligand HL and auxiliary ligands such as acetate (OAc) and bisphenyl phosphate (BPP) have been synthesized and characterized by elemental analysis, IR and single-crystal X-ray diffraction. Complex 1 crystallizes as blue single crystals that belong to the triclinic crystal system and P1 space group, while complex 2 crystallizes in a monoclinic P21/c space group. Single-crystal X-ray diffraction analysis reveals that the two copper ions in complexes 1 and 2 reside within the adjacent ligand compartments and are bridged by the endogenous phenoxo-O from ligand L and the introduction of two desired exogenous carboxylates or phosphates in the bidentate μ-1,3-bridged mode. The coordination geometries of Cu(1) and Cu(2) are both distorted square pyramids.
Two new dicopper(Ⅱ) complexes [Cu2L(OAc)2](ClO4)·H2O (1) and [Cu2L(BPP)2]-(ClO4) (2) using an asymmetric dinucleating ligand HL and auxiliary ligands such as acetate (OAc) and bisphenyl phosphate (BPP) have been synthesized and characterized by elemental analysis, IR and single-crystal X-ray diffraction. Complex 1 crystallizes as blue single crystals that belong to the triclinic crystal system and P1 space group, while complex 2 crystallizes in a monoclinic P21/c space group. Single-crystal X-ray diffraction analysis reveals that the two copper ions in complexes 1 and 2 reside within the adjacent ligand compartments and are bridged by the endogenous phenoxo-O from ligand L and the introduction of two desired exogenous carboxylates or phosphates in the bidentate μ-1,3-bridged mode. The coordination geometries of Cu(1) and Cu(2) are both distorted square pyramids.
2014, 33(4): 619-625
Abstract:
Sodium holmium polyphosphate crystal, NaHo(PO3)4, has been synthesized by the high temperature solution reaction and characterized by X-ray diffraction analysis, EDX, IR, UV-vis-NIR, and PL spectra. The structure belongs to the monoclinic system, space group P21/n with Z=4, a=7.181(3), b=13.059(5) and c=9.730 (4) Å. It is described as a three-dimensional (3D) architecture made up of [P4O12]4- anionic spiral chains and HoO8 polyhedra by corner-sharing. The 8-coordinated sodium atoms are located in infinite tunnels. The results of EDX and IR spectrum are in good agreement with the crystallographic analysis. In addition, NaHo(PO3)4 exhibits visible light emission in the solid state at room temperature.
Sodium holmium polyphosphate crystal, NaHo(PO3)4, has been synthesized by the high temperature solution reaction and characterized by X-ray diffraction analysis, EDX, IR, UV-vis-NIR, and PL spectra. The structure belongs to the monoclinic system, space group P21/n with Z=4, a=7.181(3), b=13.059(5) and c=9.730 (4) Å. It is described as a three-dimensional (3D) architecture made up of [P4O12]4- anionic spiral chains and HoO8 polyhedra by corner-sharing. The 8-coordinated sodium atoms are located in infinite tunnels. The results of EDX and IR spectrum are in good agreement with the crystallographic analysis. In addition, NaHo(PO3)4 exhibits visible light emission in the solid state at room temperature.
2014, 33(4): 626-634
Abstract:
Two coordination polymers, namely {[Co(L)(H2O)]·H2O}n (1) and [Mn(L)(phen)]n (2, H2L=5-(pyridin-4-yl)isophthalic acid, phen=1,10-phenanthroline), have been hydrothermally synthesized and characterized by elemental analysis, IR, TG, magnetic properties, and single-crystal X-ray diffraction. 1 belongs to the triclinic system, space group P1 with a=7.2188(7), b=10.0835(8), c=10.2069(7) Å, α=113.713(7), β=99.490(7), γ=104.516(8)°, V=628.24(9) Å3, C13H11NCoO6, Mr=336.16, Z=2, Dc=1.777 Mg/m3, μ(MoKα)=1.395 mm-1, F(000)=342, S=1.041, the final R=0.0381 and wR=0.0819 for 3744 observed reflections (I>2σ(I)) and R=0.0448 and wR=0.0874 for all data. 2 belongs to the monoclinic system, space group P2/c with a=12.9185(3), b=10.4343(2), c=31.7650(6) Å, β=101.282(2)°, V=4199.08(13) Å3, C50H30N6Mn2O8, Mr=952.68, Z=4, Dc=1.507 Mg/m3, μ(MoKα)=5.447 mm-1, F(000)=1944, S=1.128, the final R=0.1003 and wR=0.1052 for 8247 observed reflections (I>2σ(I)) and R=0.2595 and wR=0.2625 for all data. Single-crystal X-ray diffraction studies show that compound 1 features a 2D sheet structure based on a dicobalt(Ⅱ) subunit, which is further extended into a 3D metal-organic supramolecular framework by O-H…O hydrogen bond. Compound 2 also possesses a 2D sheet, which is held together into a 3D supramolecular architecture via C-H…O hydrogen bond and π-π stacking interactions. Magnetic studies for compound 2 show antiferromagnetic coupling between the adjacent metal centers, with J=-11.8 cm-1 and g=2.12 for 2.
Two coordination polymers, namely {[Co(L)(H2O)]·H2O}n (1) and [Mn(L)(phen)]n (2, H2L=5-(pyridin-4-yl)isophthalic acid, phen=1,10-phenanthroline), have been hydrothermally synthesized and characterized by elemental analysis, IR, TG, magnetic properties, and single-crystal X-ray diffraction. 1 belongs to the triclinic system, space group P1 with a=7.2188(7), b=10.0835(8), c=10.2069(7) Å, α=113.713(7), β=99.490(7), γ=104.516(8)°, V=628.24(9) Å3, C13H11NCoO6, Mr=336.16, Z=2, Dc=1.777 Mg/m3, μ(MoKα)=1.395 mm-1, F(000)=342, S=1.041, the final R=0.0381 and wR=0.0819 for 3744 observed reflections (I>2σ(I)) and R=0.0448 and wR=0.0874 for all data. 2 belongs to the monoclinic system, space group P2/c with a=12.9185(3), b=10.4343(2), c=31.7650(6) Å, β=101.282(2)°, V=4199.08(13) Å3, C50H30N6Mn2O8, Mr=952.68, Z=4, Dc=1.507 Mg/m3, μ(MoKα)=5.447 mm-1, F(000)=1944, S=1.128, the final R=0.1003 and wR=0.1052 for 8247 observed reflections (I>2σ(I)) and R=0.2595 and wR=0.2625 for all data. Single-crystal X-ray diffraction studies show that compound 1 features a 2D sheet structure based on a dicobalt(Ⅱ) subunit, which is further extended into a 3D metal-organic supramolecular framework by O-H…O hydrogen bond. Compound 2 also possesses a 2D sheet, which is held together into a 3D supramolecular architecture via C-H…O hydrogen bond and π-π stacking interactions. Magnetic studies for compound 2 show antiferromagnetic coupling between the adjacent metal centers, with J=-11.8 cm-1 and g=2.12 for 2.
2014, 33(4): 635-641
Abstract:
One new AgI complex, [Ag(apca)(H2O)]n (Hapca=3-aminopyrazine-2-carboxylic acid), has been prepared and structurally and spectroscopically characterized. The title complex (1) crystallizes in the monoclinic system P21/c (No. 14) with a=14.3307(9), b=14.9296(9), c=6.5824(4) Å, β=92.7430(10)°, V=1406.70(15) Å3, Z=8. Mr=264.00, Dc=2.493 g/cm3, μ=2.831 mm-1, F(000)=1024, the final R=0.0266 and wR=0.0788 for 3107 observed reflections with I>2σ(I). Its structure features a three-dimensional (3D) network composed of one-dimensional (1D) [Ag(apca)(H2O)]n ribbons interconnected via weak hydrogen bonds and π-π interactions. Emission spectra of the title complex in the solid state at room temperature give strong green luminescence.
One new AgI complex, [Ag(apca)(H2O)]n (Hapca=3-aminopyrazine-2-carboxylic acid), has been prepared and structurally and spectroscopically characterized. The title complex (1) crystallizes in the monoclinic system P21/c (No. 14) with a=14.3307(9), b=14.9296(9), c=6.5824(4) Å, β=92.7430(10)°, V=1406.70(15) Å3, Z=8. Mr=264.00, Dc=2.493 g/cm3, μ=2.831 mm-1, F(000)=1024, the final R=0.0266 and wR=0.0788 for 3107 observed reflections with I>2σ(I). Its structure features a three-dimensional (3D) network composed of one-dimensional (1D) [Ag(apca)(H2O)]n ribbons interconnected via weak hydrogen bonds and π-π interactions. Emission spectra of the title complex in the solid state at room temperature give strong green luminescence.
2014, 33(4): 642-646
Abstract:
A new cobalt complex Co(C10H8N2)(H2O)3[C9H11O2(COO)] with methy-5-norbor-nene-2,3-dicarboxylic anhydride acid (MNA) and 2,2'-bipyridine as ligands has been synthesized in the mixed solvents of ethanol and water. It crystallizes in monoclinic, space group P21/c with a=13.0430(13), b=21.014(2), c=7.5151(7) Å, β=102.319(2)°, V=2012.4(3) Å3, Dc=1.529 g/cm3, Z=4, F(000)=964, GOOF=1.051, the final R=0.0457 and wR=0.0974. The crystal structure shows that the cobalt ion is coordinated with four oxygen atoms from one MNA molecule and three water molecules together with two nitrogen atoms from the 2,2'-bipyridine molecule, forming a distorted octahedral coordination geometry. The thermal stability and electrochemical properties have studied in this paper.
A new cobalt complex Co(C10H8N2)(H2O)3[C9H11O2(COO)] with methy-5-norbor-nene-2,3-dicarboxylic anhydride acid (MNA) and 2,2'-bipyridine as ligands has been synthesized in the mixed solvents of ethanol and water. It crystallizes in monoclinic, space group P21/c with a=13.0430(13), b=21.014(2), c=7.5151(7) Å, β=102.319(2)°, V=2012.4(3) Å3, Dc=1.529 g/cm3, Z=4, F(000)=964, GOOF=1.051, the final R=0.0457 and wR=0.0974. The crystal structure shows that the cobalt ion is coordinated with four oxygen atoms from one MNA molecule and three water molecules together with two nitrogen atoms from the 2,2'-bipyridine molecule, forming a distorted octahedral coordination geometry. The thermal stability and electrochemical properties have studied in this paper.
2014, 33(4): 647-648
Abstract:
Lotus seed starch (15%, w/w) was subjected to ultra-high pressure (UHP) at 500 MPa for 10~60 min. The effects of UHP on the structural, pasting, and thermal properties of starch were investigated using solid-state 13C CP/MAS NMR, differential scanning calorimetry (DSC), HPSEC-MALLS-RI, and a rapid visco analyzer. The 13C CP/MAS NMR results revealed a reduction in the relative crystallinity and peak intensity of the crystalline state with increasing the UHP time. The molecular weight of native starch was 1.433×107 Da, which was higher than that of the UHP-treated starch. Viscograms of UHP-treated starch revealed an increase in paste viscosity, peak time, and pasting temperature and a reduction in breakdown and setback viscosity compared to the native starch. Furthermore, the DSC results showed a reduction in gelatinization temperature and gelatinization enthalpy with increasing the UHP time.
Lotus seed starch (15%, w/w) was subjected to ultra-high pressure (UHP) at 500 MPa for 10~60 min. The effects of UHP on the structural, pasting, and thermal properties of starch were investigated using solid-state 13C CP/MAS NMR, differential scanning calorimetry (DSC), HPSEC-MALLS-RI, and a rapid visco analyzer. The 13C CP/MAS NMR results revealed a reduction in the relative crystallinity and peak intensity of the crystalline state with increasing the UHP time. The molecular weight of native starch was 1.433×107 Da, which was higher than that of the UHP-treated starch. Viscograms of UHP-treated starch revealed an increase in paste viscosity, peak time, and pasting temperature and a reduction in breakdown and setback viscosity compared to the native starch. Furthermore, the DSC results showed a reduction in gelatinization temperature and gelatinization enthalpy with increasing the UHP time.
