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2016 Volume 35 Issue 6
2016, 35(6): 833-838
doi: 10.14102/j.cnki.0254-5861.2011-0968
Abstract:
The title complex is widely used as an efficient key component of Ziegler-Natta catalyst for stereospecific polymerization of dienes to produce synthetic rubbers. However, the quantitative structure-activity relationship (QSAR) of this kind of complexes is still not clear mainly due to the difficulties to obtain their geometric molecular structures through laboratory experiments. An alternative solution is the quantum chemistry calculation in which the comformational population shall be determined. In this study, ten conformers of the title complex were obtained with the function of molecular dynamics conformational search in Gabedit 2.4.8, and their geometry optimization and thermodynamics calculation were made with a Sparkle/PM7 approach in MOPAC 2012. Their Gibbs free energies at 1 atm. and 298.15 K were calculated. Population of the conformers was further calculated out according to the theory of Boltzmann distribution, indicating that one of the ten conformers has a dominant population of 77.13%.
The title complex is widely used as an efficient key component of Ziegler-Natta catalyst for stereospecific polymerization of dienes to produce synthetic rubbers. However, the quantitative structure-activity relationship (QSAR) of this kind of complexes is still not clear mainly due to the difficulties to obtain their geometric molecular structures through laboratory experiments. An alternative solution is the quantum chemistry calculation in which the comformational population shall be determined. In this study, ten conformers of the title complex were obtained with the function of molecular dynamics conformational search in Gabedit 2.4.8, and their geometry optimization and thermodynamics calculation were made with a Sparkle/PM7 approach in MOPAC 2012. Their Gibbs free energies at 1 atm. and 298.15 K were calculated. Population of the conformers was further calculated out according to the theory of Boltzmann distribution, indicating that one of the ten conformers has a dominant population of 77.13%.
2016, 35(6): 839-848
doi: 10.14102/j.cnki.0254-5861.2011-0733
Abstract:
To provide hints for the design of new acetylcholinesterase (AChE) inhibitors with higher potency and specificity, the binding modes of novel heterodimers comprised of donepezil and huperzine A fragments with AChE were explored by employing the docking simulations. The results show that the binding mode of S-17b (the most potent inhibitor in Ref. 2, i.e., Bioorg. Med. Chem. 2013, 21, 676-683) is clearly different from that of donepezil, while the binding modes of other heterodimers in Ref. 2 are the same as that of donepezil. In addition, based on the binding mode and structure modification of S-17b, two novel inhibitors (S-17b1 and S-17bb1) with much higher inhibitory potency than S-17b were obtained. Our design strategy was to replace the hupyridone moiety of S-17b with the bulky group, and to replace the dimethoxyindanone moiety of S-17b with more hydrophobic and bulky group with a highly positive charge, which would result in generating potent and selective AChE inhibitors.
To provide hints for the design of new acetylcholinesterase (AChE) inhibitors with higher potency and specificity, the binding modes of novel heterodimers comprised of donepezil and huperzine A fragments with AChE were explored by employing the docking simulations. The results show that the binding mode of S-17b (the most potent inhibitor in Ref. 2, i.e., Bioorg. Med. Chem. 2013, 21, 676-683) is clearly different from that of donepezil, while the binding modes of other heterodimers in Ref. 2 are the same as that of donepezil. In addition, based on the binding mode and structure modification of S-17b, two novel inhibitors (S-17b1 and S-17bb1) with much higher inhibitory potency than S-17b were obtained. Our design strategy was to replace the hupyridone moiety of S-17b with the bulky group, and to replace the dimethoxyindanone moiety of S-17b with more hydrophobic and bulky group with a highly positive charge, which would result in generating potent and selective AChE inhibitors.
2016, 35(6): 849-856
doi: 10.14102/j.cnki.0254-5861.2011-1058
Abstract:
Three cyclohexyltin complexes of N-(3,5-dibromosalicylidene)valine (H2L), Cy3Sn(HL) (1), Cy2SnL (2), and Cy2SnL·Cy3SnCl (3) (Cy = cyclohexyl), have been synthesized and characterized by elemental analysis, IR, and 1H and 13C NMR spectra. The crystal structures of 2 and 3 have been determined. Complex 2 belongs to the monoclinic system, space group P21/n with a = 21.250(8), b = 10.837(4), c = 23.050(8) Å, b = 93.193(9)°, V = 5300(3) Å3, Z = 8, Dc = 1.659 g/cm3, m ＝ 4.004 mm-1, F(000) = 2624, R = 0.0471 and wR = 0.1015. Complex 3 belongs to the monoclinic system, space group P21 with a = 10.3452(10), b = 18.7665(18), c = 12.1483(12) Å, b = 103.374(2)°, V = 2294.5(4) Å3, Z = 2, Dc = 1.542 g/cm3, m = 2.923 mm-1, F(000) = 1072, R = 0.0428 and wR = 0.0936. Complex 2 has a distorted trigonal bipyramidal geometry with the axial locations occupied by one carboxylate oxygen and a phenolic oxygen of the ligand, and 3 reveals that the two tin atoms are joined via the carbonyl atom of the ligand to form a mixed organotin binuclear complex. Bioassay results show that 1 and 2 have good in vitro antibacterial activity against Escherichia coli.
Three cyclohexyltin complexes of N-(3,5-dibromosalicylidene)valine (H2L), Cy3Sn(HL) (1), Cy2SnL (2), and Cy2SnL·Cy3SnCl (3) (Cy = cyclohexyl), have been synthesized and characterized by elemental analysis, IR, and 1H and 13C NMR spectra. The crystal structures of 2 and 3 have been determined. Complex 2 belongs to the monoclinic system, space group P21/n with a = 21.250(8), b = 10.837(4), c = 23.050(8) Å, b = 93.193(9)°, V = 5300(3) Å3, Z = 8, Dc = 1.659 g/cm3, m ＝ 4.004 mm-1, F(000) = 2624, R = 0.0471 and wR = 0.1015. Complex 3 belongs to the monoclinic system, space group P21 with a = 10.3452(10), b = 18.7665(18), c = 12.1483(12) Å, b = 103.374(2)°, V = 2294.5(4) Å3, Z = 2, Dc = 1.542 g/cm3, m = 2.923 mm-1, F(000) = 1072, R = 0.0428 and wR = 0.0936. Complex 2 has a distorted trigonal bipyramidal geometry with the axial locations occupied by one carboxylate oxygen and a phenolic oxygen of the ligand, and 3 reveals that the two tin atoms are joined via the carbonyl atom of the ligand to form a mixed organotin binuclear complex. Bioassay results show that 1 and 2 have good in vitro antibacterial activity against Escherichia coli.
2016, 35(6): 857-862
doi: 10.14102/j.cnki.0254-5861.2011-1051
Abstract:
A new crystal of (E)-2-(2,4-dichlorophenoxy)-1-(5,5-dimethyl-2-oxido-1,3,2-dioxa- phosphinan-2-yl)vinyl 2-(2,4-dichlorophenoxy)acetate has been determined by single-crystal X-ray diffraction. The compound crystallizes in triclinic, space group P with a = 7.9393(17), b = 11.974(3) Å, c = 13.532(3) Å, α = 90.937(4), β = 101.998(3), γ = 101.363(4)°, V = 1231.5(5) Å3, Dc = 1.500 Mg/m3, Z = 2, F(000) = 568 and μ = 0.585 mm-1. The molecular packing in the crystal is the result of C(10)–H(10)…O(5) hydrogen bond, as well as weak π-π stacking interactions. The herbicidal activity results indicated that the title compound 3 showed 80~100% inhibitory activities against all of the tested weeds at a dosage of 150 g·ai/ha.
A new crystal of (E)-2-(2,4-dichlorophenoxy)-1-(5,5-dimethyl-2-oxido-1,3,2-dioxa- phosphinan-2-yl)vinyl 2-(2,4-dichlorophenoxy)acetate has been determined by single-crystal X-ray diffraction. The compound crystallizes in triclinic, space group P with a = 7.9393(17), b = 11.974(3) Å, c = 13.532(3) Å, α = 90.937(4), β = 101.998(3), γ = 101.363(4)°, V = 1231.5(5) Å3, Dc = 1.500 Mg/m3, Z = 2, F(000) = 568 and μ = 0.585 mm-1. The molecular packing in the crystal is the result of C(10)–H(10)…O(5) hydrogen bond, as well as weak π-π stacking interactions. The herbicidal activity results indicated that the title compound 3 showed 80~100% inhibitory activities against all of the tested weeds at a dosage of 150 g·ai/ha.
2016, 35(6): 863-871
doi: 10.14102/j.cnki.0254-5861.2011-0981
Abstract:
The title complexes based on 4(3H)-quinazolinone ligand have been synthesized and characterized by elemental analysis, IR spectrum and single-crystal X-ray diffraction analysis. Complex 1 belongs to the triclinic system, space group P , with a = 6.5392(3), b = 7.4402(5), c = 10.3397(7) Å, α = 83.204(5), β = 75.465(5), γ = 86.075(5)° and V = 483.88(5) Å3. Complex 2 is of orthorhombic system, space group Pbca, with a = 10.1294(3), b = 7.6747(5), c = 23.8171(15) Å and V = 1849.1(4) Å3. Complex 3 belongs to the orthorhombic system, space group Pbca, with a = 12.7188(2), b = 6.66582 (9), c = 25.6987(6) Å and V = 2178.77(5) Å3. The complex structures are affected by the synthesis conditions.
The title complexes based on 4(3H)-quinazolinone ligand have been synthesized and characterized by elemental analysis, IR spectrum and single-crystal X-ray diffraction analysis. Complex 1 belongs to the triclinic system, space group P , with a = 6.5392(3), b = 7.4402(5), c = 10.3397(7) Å, α = 83.204(5), β = 75.465(5), γ = 86.075(5)° and V = 483.88(5) Å3. Complex 2 is of orthorhombic system, space group Pbca, with a = 10.1294(3), b = 7.6747(5), c = 23.8171(15) Å and V = 1849.1(4) Å3. Complex 3 belongs to the orthorhombic system, space group Pbca, with a = 12.7188(2), b = 6.66582 (9), c = 25.6987(6) Å and V = 2178.77(5) Å3. The complex structures are affected by the synthesis conditions.
2016, 35(6): 872-878
doi: 10.14102/j.cnki.0254-5861.2011-1158
Abstract:
The Ag/γ-Fe2O3 nanocomposite was synthesized by solvothermal reduction method via using ferric nitrate and silver nitrate as raw materials, and ethylene glycol as the reducing agent. The composite was characterized by X-ray powder diffraction, scanning electron microscope, transmission electron microscope, and energy dispersive X-ray. The prepared Ag/γ-Fe2O3 was used for the catalytic hydrogenation of nitrobenzene to aniline by hydrazine hydrate. The factors such as the silver content in the catalyst, reaction time, reaction temperature and the regeneration of catalyst were investigated. The results showed that the yield of aniline reached 100% by utilizing the 1%wt (nitrobenzene) Ag/γ-Fe2O3 for the catalytic hydrogenation of nitrobenzene for 3 h to obtain aniline at 78 ℃, hydrazine hydrate as the hydrogen source, while the silver content in the catalyst was 3%mol.
The Ag/γ-Fe2O3 nanocomposite was synthesized by solvothermal reduction method via using ferric nitrate and silver nitrate as raw materials, and ethylene glycol as the reducing agent. The composite was characterized by X-ray powder diffraction, scanning electron microscope, transmission electron microscope, and energy dispersive X-ray. The prepared Ag/γ-Fe2O3 was used for the catalytic hydrogenation of nitrobenzene to aniline by hydrazine hydrate. The factors such as the silver content in the catalyst, reaction time, reaction temperature and the regeneration of catalyst were investigated. The results showed that the yield of aniline reached 100% by utilizing the 1%wt (nitrobenzene) Ag/γ-Fe2O3 for the catalytic hydrogenation of nitrobenzene for 3 h to obtain aniline at 78 ℃, hydrazine hydrate as the hydrogen source, while the silver content in the catalyst was 3%mol.
2016, 35(6): 879-888
doi: 10.14102/j.cnki.0254-5861.2011-1002
Abstract:
Al(OH)3 modified nickel slag adsorbent was prepared by sintering technology. The structure of the sample was characterized by BET, XRD, IR, SEM and EDAX. The sample's adsorption performance of Pb2+ and Cu2+ from aqueous solution was studied. Results indicated that the adsorbent is a loose and porous mesoporous material. Its surface had mass aluminosilicate, high-activity γ-Al2O3 and its pH ranges from 4 to 12 that all have negative charges. The BET surface of the adsorbent is 23.90 m2/g. Furthermore, its surface contains rich oxygenic functional groups, which could not only provide abundant adsorption sites for Pb2+ and Cu2+, but also improve the adsorption performance of Pb2+ and Cu2+ from waste water through the complexation of heavy metal ions. The best pH values selected in the adsorption of Pb2+ and Cu2+ are 6 and 5, respectively. With the increase of the initial concentration of simulated solution, the adsorption capacities of Pb2+ and Cu2+ gradually increased but the removal rates showed a downward trend. The competitive adsorption results of Pb2+ and Cu2+ showed that Pb2+ has better preferential adsorption than Cu2+.
Al(OH)3 modified nickel slag adsorbent was prepared by sintering technology. The structure of the sample was characterized by BET, XRD, IR, SEM and EDAX. The sample's adsorption performance of Pb2+ and Cu2+ from aqueous solution was studied. Results indicated that the adsorbent is a loose and porous mesoporous material. Its surface had mass aluminosilicate, high-activity γ-Al2O3 and its pH ranges from 4 to 12 that all have negative charges. The BET surface of the adsorbent is 23.90 m2/g. Furthermore, its surface contains rich oxygenic functional groups, which could not only provide abundant adsorption sites for Pb2+ and Cu2+, but also improve the adsorption performance of Pb2+ and Cu2+ from waste water through the complexation of heavy metal ions. The best pH values selected in the adsorption of Pb2+ and Cu2+ are 6 and 5, respectively. With the increase of the initial concentration of simulated solution, the adsorption capacities of Pb2+ and Cu2+ gradually increased but the removal rates showed a downward trend. The competitive adsorption results of Pb2+ and Cu2+ showed that Pb2+ has better preferential adsorption than Cu2+.
2016, 35(6): 889-902
doi: 10.14102/j.cnki.0254-5861.2011-1052
Abstract:
Pt/FeSnO(OH)5 was synthesized as a novel catalyst for VOCs oxidation. Compared with Pt/γ-Al2O3 during catalytic oxidation of benzene, Pt/FeSnO(OH)5 showed better catalytic activity. After characterization of the catalysts by XRD, SEM, TEM, EDS, XPS, BET, TGA and DTA, we found most Pt could be reduced to metallic state when the hydroxyl catalyst was used as supporter, and the metallic Pt in Pt/FeSnO(OH)5 was more active than the oxidized Pt in Pt/γ-Al2O3 in catalytic oxidation of VOCs. Pt/FeSnO(OH)5 shows both good catalytic activity and high stability, which may be a promising catalyst. This study may also be helpful for the design and fabrication of new catalysts.
Pt/FeSnO(OH)5 was synthesized as a novel catalyst for VOCs oxidation. Compared with Pt/γ-Al2O3 during catalytic oxidation of benzene, Pt/FeSnO(OH)5 showed better catalytic activity. After characterization of the catalysts by XRD, SEM, TEM, EDS, XPS, BET, TGA and DTA, we found most Pt could be reduced to metallic state when the hydroxyl catalyst was used as supporter, and the metallic Pt in Pt/FeSnO(OH)5 was more active than the oxidized Pt in Pt/γ-Al2O3 in catalytic oxidation of VOCs. Pt/FeSnO(OH)5 shows both good catalytic activity and high stability, which may be a promising catalyst. This study may also be helpful for the design and fabrication of new catalysts.
2016, 35(6): 903-913
doi: 10.14102/j.cnki.0254-5861.2011-1008
Abstract:
Two new metal-organic frameworks (MOFs), namely, [Co2(L1)(bix)(µ3-OH)]·2H2O (1) and [Co2(L2)(bix)(µ3-OH)]·2.5H2O (2) (H3L1 = 5-oxyacetate isophthalic acid, H3L2 = 3,5-bis-oxyacetate-benzoic acid, bix = 1,4-bis(imidazol-1-ylmethyl)benzene), have been synthesized under hydrothermal conditions. Their structures were determined by single-crystal X-ray diffraction analysis and further characterized by elemental analysis, IR spectra, and powder X-ray diffraction (PXRD) analysis. Both complexes 1 and 2 demonstrate identical three-dimensional (3D) (3,8)-connected tfz-d nets with (43)2(46·618·84) topologies, where the tetranuclear [Co4(μ3-OH)2] clusters act as 8-connected nodes and aromatic multicarboxylic ligands as 3-connected nodes. The results show that the ligands with different geometrical conformations can form products with the same topological structures. Their thermal and magnetic properties were also investigated.
Two new metal-organic frameworks (MOFs), namely, [Co2(L1)(bix)(µ3-OH)]·2H2O (1) and [Co2(L2)(bix)(µ3-OH)]·2.5H2O (2) (H3L1 = 5-oxyacetate isophthalic acid, H3L2 = 3,5-bis-oxyacetate-benzoic acid, bix = 1,4-bis(imidazol-1-ylmethyl)benzene), have been synthesized under hydrothermal conditions. Their structures were determined by single-crystal X-ray diffraction analysis and further characterized by elemental analysis, IR spectra, and powder X-ray diffraction (PXRD) analysis. Both complexes 1 and 2 demonstrate identical three-dimensional (3D) (3,8)-connected tfz-d nets with (43)2(46·618·84) topologies, where the tetranuclear [Co4(μ3-OH)2] clusters act as 8-connected nodes and aromatic multicarboxylic ligands as 3-connected nodes. The results show that the ligands with different geometrical conformations can form products with the same topological structures. Their thermal and magnetic properties were also investigated.
2016, 35(6): 914-920
doi: 10.14102/j.cnki.0254-5861.2011-1001
Abstract:
A new Cd(II) coordination polymer, namely {Cd2(L)(biimpy)(H2O)}n (1, H4L = 3-(3',5'-dicarboxylphenoxy)phthalic acid, biimpy = 2,6-bis(1-imdazoly)pyridine), has been success- fully synthesized via the hydrothermal reactions of Cd(II) ions, H4L and biimpy. The crystal structure is of triclinic, space group P with a = 7.7874(5), b = 9.9716(5), c = 18.5278(6) Å, α = 91.327(4), β = 96.689(4), γ = 111.896(5)°, V = 1322.39(12) Å3, C27H17Cd2N5O10, Mr = 796.26, Z = 2, Dc = 2.000 g/cm3, F(000) = 780, μ = 1.679 mm-1, R = 0.0345 and wR = 0.0767 for 3890 observed reflections (I > 2s(I)). Single-crystal X-ray structural analysis reveals that compound 1 features a three-dimensional (3D) framework based on two different dinuclear [Cd2(COO)2] building subunits, and topological analysis shows that it can be simplified into a binodal (4,6)-connected topological network with the point symbol of {3.42.52.6}{32.42.52.64.74.8}. Moreover, the thermal stability and luminescent property of compound 1 were also studied.
A new Cd(II) coordination polymer, namely {Cd2(L)(biimpy)(H2O)}n (1, H4L = 3-(3',5'-dicarboxylphenoxy)phthalic acid, biimpy = 2,6-bis(1-imdazoly)pyridine), has been success- fully synthesized via the hydrothermal reactions of Cd(II) ions, H4L and biimpy. The crystal structure is of triclinic, space group P with a = 7.7874(5), b = 9.9716(5), c = 18.5278(6) Å, α = 91.327(4), β = 96.689(4), γ = 111.896(5)°, V = 1322.39(12) Å3, C27H17Cd2N5O10, Mr = 796.26, Z = 2, Dc = 2.000 g/cm3, F(000) = 780, μ = 1.679 mm-1, R = 0.0345 and wR = 0.0767 for 3890 observed reflections (I > 2s(I)). Single-crystal X-ray structural analysis reveals that compound 1 features a three-dimensional (3D) framework based on two different dinuclear [Cd2(COO)2] building subunits, and topological analysis shows that it can be simplified into a binodal (4,6)-connected topological network with the point symbol of {3.42.52.6}{32.42.52.64.74.8}. Moreover, the thermal stability and luminescent property of compound 1 were also studied.
2016, 35(6): 921-928
doi: 10.14102/j.cnki.0254-5861.2011-0974
Abstract:
The reaction of Cd(NO3)2·4H2O with 4,4'-dipyridylacetylene (4,4'-DPA) and 2-nitroterephthalic acid (2-NO2-H2BDC) in DMF/H2O mixed solvent has afforded a compound {[Cd(2-NO2-BDC)(4,4'-DPA)]·(DMF)}n (1). Compound 1 has been characterized by single-crystal X-ray diffraction, powder X-ray diffraction, thermogravimetry analysis, and IR spectrum. Com- pound 1 crystallizes in the monoclinic system, space group P21/n, with a = 12.1488(3), b = 14.6689(3), c = 13.1615(3) Å, β = 111.809(3)o, V = 2177.63(9) Å3, Z = 4, C23H18 N4O7Cd, Mr = 574.81, Dc = 1.753 g/cm3, μ = 8.523 mm-1, F(000) = 1152, the final R = 0.0411 and wR = 0.1064 for 3589 observed reflections with I > 2s(I). In compound 1, the Cd(II) ions are linked by the carboxylate groups of 2-NO2-BDC ligands to give a two-dimensional layered structure based on the centrosymmetric dinuclear Cd2(COO)2 units, which are further connected by the 4,4'-DPA ligands to produce a three-dimensional framework with pcu topology. Careful examination revealed that compound 1 is a 2-fold interpenetrating framework. Furthermore, the gas adsorption properties of 1 for N2 and CO2 have also been investigated.
The reaction of Cd(NO3)2·4H2O with 4,4'-dipyridylacetylene (4,4'-DPA) and 2-nitroterephthalic acid (2-NO2-H2BDC) in DMF/H2O mixed solvent has afforded a compound {[Cd(2-NO2-BDC)(4,4'-DPA)]·(DMF)}n (1). Compound 1 has been characterized by single-crystal X-ray diffraction, powder X-ray diffraction, thermogravimetry analysis, and IR spectrum. Com- pound 1 crystallizes in the monoclinic system, space group P21/n, with a = 12.1488(3), b = 14.6689(3), c = 13.1615(3) Å, β = 111.809(3)o, V = 2177.63(9) Å3, Z = 4, C23H18 N4O7Cd, Mr = 574.81, Dc = 1.753 g/cm3, μ = 8.523 mm-1, F(000) = 1152, the final R = 0.0411 and wR = 0.1064 for 3589 observed reflections with I > 2s(I). In compound 1, the Cd(II) ions are linked by the carboxylate groups of 2-NO2-BDC ligands to give a two-dimensional layered structure based on the centrosymmetric dinuclear Cd2(COO)2 units, which are further connected by the 4,4'-DPA ligands to produce a three-dimensional framework with pcu topology. Careful examination revealed that compound 1 is a 2-fold interpenetrating framework. Furthermore, the gas adsorption properties of 1 for N2 and CO2 have also been investigated.
2016, 35(6): 929-938
doi: 10.14102/j.cnki.0254-5861.2011-0984
Abstract:
In order to perform a study on the structural modulation in the Cd(II)-L architecture (HL = (E)-2-[2-(3-pyridyl)ethenyl]-8-hydroxyquinoline), two different dicarboxylic acids, namely, 2-aminoterephthalic acid (H2ATA) and 4,4'-biphenyldicarboxylic acid (H2BPDC), are employed as the secondary auxiliary ligands. Two new complexes [Cd2L2(ATA)] (1) and [Cd2L2(BPDC)·2MeOH· 4H2O] (2) with distinct 3D frameworks were obtained. In complex 1, ligands ATA bridge the 1D Cd(II)-L infinite chains into a 3D polymeric coordination network. Complex 2 is a 3D porous framework, in which adjacent 2D Cd(II)-L coordination layers were linked together by the coor- dinated BPDC ligands. The variant structures of two complexes indicate that the skeleton of dicarboxylate anions plays a great role in the assembly of such different frameworks. In addition, the photoluminescent properties (fluorescent emission, lifetime, and quantum yield) of polymers 1 and 2 were also investigated in the solid state.
In order to perform a study on the structural modulation in the Cd(II)-L architecture (HL = (E)-2-[2-(3-pyridyl)ethenyl]-8-hydroxyquinoline), two different dicarboxylic acids, namely, 2-aminoterephthalic acid (H2ATA) and 4,4'-biphenyldicarboxylic acid (H2BPDC), are employed as the secondary auxiliary ligands. Two new complexes [Cd2L2(ATA)] (1) and [Cd2L2(BPDC)·2MeOH· 4H2O] (2) with distinct 3D frameworks were obtained. In complex 1, ligands ATA bridge the 1D Cd(II)-L infinite chains into a 3D polymeric coordination network. Complex 2 is a 3D porous framework, in which adjacent 2D Cd(II)-L coordination layers were linked together by the coor- dinated BPDC ligands. The variant structures of two complexes indicate that the skeleton of dicarboxylate anions plays a great role in the assembly of such different frameworks. In addition, the photoluminescent properties (fluorescent emission, lifetime, and quantum yield) of polymers 1 and 2 were also investigated in the solid state.
2016, 35(6): 939-945
doi: 10.14102/j.cnki.0254-5861.2011-0988
Abstract:
Two high coordination crystals were obtained by the interaction of Ce3+ and Nd3+ with polypyridyl quinoxaline ligand 2,3,6,7,10,11-hexakis(2-pyridyl)dipyrazino[2,3-f:20,30-h]qui- noxaline (HPDQ), and they were characterized. Complex 1 exhibits a 0 dimensional three-nuclear structure, with the three Ce(III) atoms being ten-, eleven- and twelve-coordinated. Complex 2 is a 0 dimensional dual-core structure and the Nd(III) atom is ten-coordinated. Complex 1 is of mono- clinic system, space group P2/c with a = 16.850(3), b = 16.617(3), c = 24.017(5) Å, β = 100.94(3)o, V = 6602(2) Å3, Z = 4, S = 1.062, F(000) = 3372, R = 0.0504 and wR = 0.1463 (I> 2σ(I)). Complex 2 adopts a monoclinic system, space group C2/c with a = 25.795(5), b = 20.166(4), c = 13.059(3) Å, β = 112.29(3)o, V = 6286(2) Å3, Z = 4, S = 1.004, F(000) = 2664, R = 0.0663 and wR = 0.1821 (I > 2σ(I)). Furthermore, the behaviors of HPDQ with Ce3+ and Nd3+ in the solution are also investigated. After the Ce3+ is added, the ultraviolet absorption of the solution is enhanced with a red shift compared with that of the HPDQ ligand. While after adding Nd3+, the ultraviolet absorption of the solution is weakened, and it has a red shift which is the same as Ce3+. However, after the respective addition of metal ions, the emission of all solutions is quenched and has a red shift compared with that of the HPDQ ligand.
Two high coordination crystals were obtained by the interaction of Ce3+ and Nd3+ with polypyridyl quinoxaline ligand 2,3,6,7,10,11-hexakis(2-pyridyl)dipyrazino[2,3-f:20,30-h]qui- noxaline (HPDQ), and they were characterized. Complex 1 exhibits a 0 dimensional three-nuclear structure, with the three Ce(III) atoms being ten-, eleven- and twelve-coordinated. Complex 2 is a 0 dimensional dual-core structure and the Nd(III) atom is ten-coordinated. Complex 1 is of mono- clinic system, space group P2/c with a = 16.850(3), b = 16.617(3), c = 24.017(5) Å, β = 100.94(3)o, V = 6602(2) Å3, Z = 4, S = 1.062, F(000) = 3372, R = 0.0504 and wR = 0.1463 (I> 2σ(I)). Complex 2 adopts a monoclinic system, space group C2/c with a = 25.795(5), b = 20.166(4), c = 13.059(3) Å, β = 112.29(3)o, V = 6286(2) Å3, Z = 4, S = 1.004, F(000) = 2664, R = 0.0663 and wR = 0.1821 (I > 2σ(I)). Furthermore, the behaviors of HPDQ with Ce3+ and Nd3+ in the solution are also investigated. After the Ce3+ is added, the ultraviolet absorption of the solution is enhanced with a red shift compared with that of the HPDQ ligand. While after adding Nd3+, the ultraviolet absorption of the solution is weakened, and it has a red shift which is the same as Ce3+. However, after the respective addition of metal ions, the emission of all solutions is quenched and has a red shift compared with that of the HPDQ ligand.
2016, 35(6): 946-952
doi: 10.14102/j.cnki.0254-5861.2011-0963
Abstract:
Reactions of Sn powder, cadmium iodide, rubidium carbonate, and sodium sulfide yielded two new compounds: three-dimensional chalcogenide RbNa3Cd2Sn2S8 (1) and layered ternary compound Na2CdS2 (2). 1 and 2 have been determined by single-crystal X-ray diffraction: 1 belongs to the orthorhombic space group Pca21, with a = 13.486(3), b = 6.7310(14), c = 18.401(4) Å and Z = 4; 2 crystallizes in the R3m space group, with a = 3.718(3), c = 26.170(4) Å and Z = 3. Study of the yellow block shaped crystals of 1 reveals that the structure consists of tetrahedral CdS4 and SnS4. The {Cd2Sn2S8} cluster shows a 12-numbered ring structure assembled by corner-sharing of alternating SnS4 and CdS4, and the rubidium and sodium ions act as void-filling and charge compensating cations. The dark orange hexagonal crystal of compound 2 consists of a unique [CdS2]2- layer, which are separated by the Na+. UV/Vis absorption spectrum exhibits the materials 1 and 2 have semiconductor properties.
Reactions of Sn powder, cadmium iodide, rubidium carbonate, and sodium sulfide yielded two new compounds: three-dimensional chalcogenide RbNa3Cd2Sn2S8 (1) and layered ternary compound Na2CdS2 (2). 1 and 2 have been determined by single-crystal X-ray diffraction: 1 belongs to the orthorhombic space group Pca21, with a = 13.486(3), b = 6.7310(14), c = 18.401(4) Å and Z = 4; 2 crystallizes in the R3m space group, with a = 3.718(3), c = 26.170(4) Å and Z = 3. Study of the yellow block shaped crystals of 1 reveals that the structure consists of tetrahedral CdS4 and SnS4. The {Cd2Sn2S8} cluster shows a 12-numbered ring structure assembled by corner-sharing of alternating SnS4 and CdS4, and the rubidium and sodium ions act as void-filling and charge compensating cations. The dark orange hexagonal crystal of compound 2 consists of a unique [CdS2]2- layer, which are separated by the Na+. UV/Vis absorption spectrum exhibits the materials 1 and 2 have semiconductor properties.
2016, 35(6): 953-958
doi: 10.14102/j.cnki.0254-5861.2011-0973
Abstract:
A new 3D copper(II) coordination polymer, {[Cu2(tbip)2(1,3,5-tib)]·2H2O}n (1, H2tbip = 5-tert-butyl isophthalic acid, 1,3,5-tib = 1,3,5-tris(1-imidazolyl)benzene), has been synthe- sized by hydrothermal reaction of Cu(OAc)2·4H2O, H2tbip and 1,3,5-tib. It has been structurally characterized by element analysis, IR and magnetic measurement. X-ray single-crystal analysis was carried out for 1, which crystallizes in the triclinic system, space group P with a = 7.822(3), b = 15.854(6), c = 17.553(6) Å, a = 113.033(4), β = 90.694(4), g = 101.006(4)°, V = 1957.3(12) Å3, Z = 1, Dc = 1.493 g/cm3, Mr = 1759.70, F(000) = 908, R = 0.0721 and wR = 0.1978 with I > 2s(I). The single-crystal X-ray diffraction studies reveal that compound 1 exhibits 2D [Cu(tbip)] layers which are further pillared by 1,3,5-tib ancillary ligand with terminal tridentate coordination mode to generate the final 3D structure. Magnetic susceptibility data for 1 have been measured in the range of 2~300 K. There are antiferromagnetic interactions between copper ions of the compound.
A new 3D copper(II) coordination polymer, {[Cu2(tbip)2(1,3,5-tib)]·2H2O}n (1, H2tbip = 5-tert-butyl isophthalic acid, 1,3,5-tib = 1,3,5-tris(1-imidazolyl)benzene), has been synthe- sized by hydrothermal reaction of Cu(OAc)2·4H2O, H2tbip and 1,3,5-tib. It has been structurally characterized by element analysis, IR and magnetic measurement. X-ray single-crystal analysis was carried out for 1, which crystallizes in the triclinic system, space group P with a = 7.822(3), b = 15.854(6), c = 17.553(6) Å, a = 113.033(4), β = 90.694(4), g = 101.006(4)°, V = 1957.3(12) Å3, Z = 1, Dc = 1.493 g/cm3, Mr = 1759.70, F(000) = 908, R = 0.0721 and wR = 0.1978 with I > 2s(I). The single-crystal X-ray diffraction studies reveal that compound 1 exhibits 2D [Cu(tbip)] layers which are further pillared by 1,3,5-tib ancillary ligand with terminal tridentate coordination mode to generate the final 3D structure. Magnetic susceptibility data for 1 have been measured in the range of 2~300 K. There are antiferromagnetic interactions between copper ions of the compound.
2016, 35(6): 959-964
doi: 10.14102/j.cnki.0254-5861.2011-0970
Abstract:
A new complex with the formula [Co(acac)2(NITQ)2]·2CH2Cl2 1 (acac = acety- lacetone, NITQ = 2-(2´-quinoxalinyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide), was synthe- sized and elucidated structurally as well as magnetically in detail. The crystal belongs to the mono- clinic system, space group P21/c with a = 9.6896(1), b = 20.539(4), c = 12.147(2) Å, β = 93.84(3)°, Mr = 997.65, V = 2412.1(8) Å3, Z = 2, Dc = 1.374 g/cm3, F(000) = 1038, m = 0.635 mm-1, the final R = 0.0539 and wR = 0.1289 for 5998 observed reflections (I > 2σ(I)). The Co(II) ion is coordinated by two nitrogen atoms of quinoxaline rings from two NITQs and four oxygen atoms from two acac ions to complete a distorted octahedral coordination environment. Compound 1 is further linked into a three-dimensional (3D) supramolecular network by hydrogen-bonding, Cl…O weak contact and π…π stacking interactions. The magnetic measurements show compound 1 exhibits weak ferroma- gnetic interactions.
A new complex with the formula [Co(acac)2(NITQ)2]·2CH2Cl2 1 (acac = acety- lacetone, NITQ = 2-(2´-quinoxalinyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide), was synthe- sized and elucidated structurally as well as magnetically in detail. The crystal belongs to the mono- clinic system, space group P21/c with a = 9.6896(1), b = 20.539(4), c = 12.147(2) Å, β = 93.84(3)°, Mr = 997.65, V = 2412.1(8) Å3, Z = 2, Dc = 1.374 g/cm3, F(000) = 1038, m = 0.635 mm-1, the final R = 0.0539 and wR = 0.1289 for 5998 observed reflections (I > 2σ(I)). The Co(II) ion is coordinated by two nitrogen atoms of quinoxaline rings from two NITQs and four oxygen atoms from two acac ions to complete a distorted octahedral coordination environment. Compound 1 is further linked into a three-dimensional (3D) supramolecular network by hydrogen-bonding, Cl…O weak contact and π…π stacking interactions. The magnetic measurements show compound 1 exhibits weak ferroma- gnetic interactions.
2016, 35(6): 965-972
doi: 10.14102/j.cnki.0254-5861.2011-0992
Abstract:
Two new transition metal complexes based on chiral Schiff base ligand, namely Zn(L1)2 (1) and Cd(L2)2 (2) (L1 = (R,E)-3-(2-hydroxy-3-methoxybenzylideneamino)propane-1,2-diol, L2= (R,E)-2-((2-hydroxy-1-phenylethylimino)methyl)-6-methoxyphenol), have been synthesized and characterized. Single-crystal X-ray diffractions reveal that both 1 and 2 crystallize in the same monoclinic space group C2. 1 is four-coordinated, while 2 is six-coordinated. Complexes 1 and 2 show fluorescent emission at 479 and 580 nm, respectively. Moreover, 1 and 2 exhibit selective and sensitive recognition toward Zn2+/Cd2+ ions in the methanol solution.
Two new transition metal complexes based on chiral Schiff base ligand, namely Zn(L1)2 (1) and Cd(L2)2 (2) (L1 = (R,E)-3-(2-hydroxy-3-methoxybenzylideneamino)propane-1,2-diol, L2= (R,E)-2-((2-hydroxy-1-phenylethylimino)methyl)-6-methoxyphenol), have been synthesized and characterized. Single-crystal X-ray diffractions reveal that both 1 and 2 crystallize in the same monoclinic space group C2. 1 is four-coordinated, while 2 is six-coordinated. Complexes 1 and 2 show fluorescent emission at 479 and 580 nm, respectively. Moreover, 1 and 2 exhibit selective and sensitive recognition toward Zn2+/Cd2+ ions in the methanol solution.
2016, 35(6): 973-979
doi: 10.14102/j.cnki.0254-5861.2011-0966
Abstract:
Two novel clusters [MnIII3(m3-O)(phendox)3]X·13H2O (X = Cl (1), Br (2]) have been obtained from the solvothermal reactions of 1,10-phenanthroline-2,9-dicarbaldehyde dioxime (H2phendox) with MnCl2·4H2O or anhydrous MnBr2, and their structures were characterized by elemental analysis, FT-IR, XRD, TGA, MS and single-crystal X-ray diffraction. It crystallizes in trigonal, space group P31/c. X-ray analysis reveals that the neighbouring [Mn3(m3-O)(phendox)3]+ cores are linked by C–H…Cl hydrogen bonds and form an infinite supramolecular chain along the c-axis. Neighbouring chains are packed with each other by off-set p-p interactions of the aromatic rings on phenox2-. A 3D supramolecular architecture in a honeycomb topology is formed with 1D hexagonal channel in the dimensions of 13Å × 13Å along the c-axis. The gas adsorption studies show that compound 1·13H2O is stable upon the removal of guest molecules and the desolvated compound absorbed considerable amount of CO2.
Two novel clusters [MnIII3(m3-O)(phendox)3]X·13H2O (X = Cl (1), Br (2]) have been obtained from the solvothermal reactions of 1,10-phenanthroline-2,9-dicarbaldehyde dioxime (H2phendox) with MnCl2·4H2O or anhydrous MnBr2, and their structures were characterized by elemental analysis, FT-IR, XRD, TGA, MS and single-crystal X-ray diffraction. It crystallizes in trigonal, space group P31/c. X-ray analysis reveals that the neighbouring [Mn3(m3-O)(phendox)3]+ cores are linked by C–H…Cl hydrogen bonds and form an infinite supramolecular chain along the c-axis. Neighbouring chains are packed with each other by off-set p-p interactions of the aromatic rings on phenox2-. A 3D supramolecular architecture in a honeycomb topology is formed with 1D hexagonal channel in the dimensions of 13Å × 13Å along the c-axis. The gas adsorption studies show that compound 1·13H2O is stable upon the removal of guest molecules and the desolvated compound absorbed considerable amount of CO2.
2016, 35(6): 980-986
doi: 10.14102/j.cnki.0254-5861.2011-0976
Abstract:
A new 3D cobalt metal-organic framework [C7H13N2]2[(CH3COO)2Co7(oba)5- (Hoba)2(OH)2]·H2O has been synthesized under ionothermal conditions and characterized by elemental analysis, FT-IR, XRD, and TG. This complex crystallizes in monoclinic system, space group P21/c with a = 19.4499(4), b = 10.8839(2), c = 27.7796(5) Å, β = 104.467(2)°, V = 5694.22(19) Å3, Z = 2, C116H92Co7N4O42, Mr = 2626.45, Dc = 1.532 g/cm3, F(000) = 2682, μ = 1.085 mm-1, R = 0.0387 and wR = 0.1177. Its structure is characterized as a 3D open framework constructed by seven nuclear clusters [(CH3COO)2Co7(OH)2] and the 4,4'-oxybisbenzoic acid ligand. The used ILs cations are located in the middle of the pore and compensate for the negative charges of framework. Furthermore, its fluorescence property has also been studied.
A new 3D cobalt metal-organic framework [C7H13N2]2[(CH3COO)2Co7(oba)5- (Hoba)2(OH)2]·H2O has been synthesized under ionothermal conditions and characterized by elemental analysis, FT-IR, XRD, and TG. This complex crystallizes in monoclinic system, space group P21/c with a = 19.4499(4), b = 10.8839(2), c = 27.7796(5) Å, β = 104.467(2)°, V = 5694.22(19) Å3, Z = 2, C116H92Co7N4O42, Mr = 2626.45, Dc = 1.532 g/cm3, F(000) = 2682, μ = 1.085 mm-1, R = 0.0387 and wR = 0.1177. Its structure is characterized as a 3D open framework constructed by seven nuclear clusters [(CH3COO)2Co7(OH)2] and the 4,4'-oxybisbenzoic acid ligand. The used ILs cations are located in the middle of the pore and compensate for the negative charges of framework. Furthermore, its fluorescence property has also been studied.
