Two new Cu（II） coordination polymers, [Cu（FDA）（BPY）（H20）]n （1） and {[Cu（FDA）（BPY）（H2O）].2H2O}n （2） （H2FDA = 2,5-furandicarboxylic acid, BPY = 2,2＇-bipyridine）, have been synthesized and structural...Two new Cu（II） coordination polymers, [Cu（FDA）（BPY）（H20）]n （1） and {[Cu（FDA）（BPY）（H2O）].2H2O}n （2） （H2FDA = 2,5-furandicarboxylic acid, BPY = 2,2＇-bipyridine）, have been synthesized and structurally characterized by single-crystal X-ray diffraction as well as elemental analysis and IR. Compound 1 crystallizes in monoclinic, space group P21/c, with a = 7.5915（15）, b = 8.4050（17）, c = 24.204（6） A, β = 99.05（3）°, V= 1525.1（6） A3, Dc = 1.706 g/crn3, C16HI2CuN206, Mr = 391.82, F（000） = 796, μ（MoKa） = 1.470 mm-l, Z = 4, R = 0.0633 and wR = 0.1059 for 2389 observed reflections （1 〉 2a（I））, R = 0.0738, and wR = 0.1098 for all data. Complex 2 belongs to triclinic space group PI with a = 8.8660（18）, b = 8.9112（18）, c = 12.525（3） A, a = 88.41（3）, β = 69.38（3）, γ = 66.95（3）°, V = 845.2（3） A3, Dc = 1.681 g/cm3, CI6HI6CuN2Os, Mr. = 427.85, F（000） = 438, μ（MoKα） = 1.342 mm-1, Z = 2, R = 0.0290 and wR = 0.0690 for 2767 observed reflections （I 〉 2σ（I））, R = 0.0329 and wR = 0.0706 for all data. Complexes 1 and 2 are both coordination polymers with one-dimensional chain structures bridged by the protonated FDA ligands, which are assembled into three-dimensional supramolecular structures through hydrogen bonding interactions and π-π packing interactions between the chains.展开更多
采用水热-煅烧法制备了磁性镍铁尖晶石载体NiFe_(2)O_(4),再采用浸渍-还原法在载体上负载Ru纳米粒子制备Ru/NiFe_(2)O_(4)催化剂。采用X射线衍射(XRD)、N2吸附-脱附(BET)、NH3程序升温脱附(NH3-TPD)、H_(2)程序升温还原(H_(2)-TPR)、X...采用水热-煅烧法制备了磁性镍铁尖晶石载体NiFe_(2)O_(4),再采用浸渍-还原法在载体上负载Ru纳米粒子制备Ru/NiFe_(2)O_(4)催化剂。采用X射线衍射(XRD)、N2吸附-脱附(BET)、NH3程序升温脱附(NH3-TPD)、H_(2)程序升温还原(H_(2)-TPR)、X射线光电子能谱(XPS)和电感耦合等离子体发射光谱(ICP-OES)测试对催化剂进行表征分析。结果表明,Ru/NiFe_(2)O_(4)催化剂表面氧物种丰富,相较于载体,负载Ru后催化剂比表面积和表面酸量增加,Ru与载体存在相互作用,这可能是催化剂高活性和高稳定性的关键。将催化剂用于5-羟甲基糠醛(HMF)的选择性氧化,负载Ru后,催化剂催化活性显著提升。对反应条件进行优化,在添加0.08 g KHCO3,氧化剂O2压力为1 MPa,反应温度为80℃,使用0.1 g Ru/NiFe_(2)O_(4)催化剂,在水溶液中反应12 h HMF能完全转化,2,5-呋喃二甲酸(FDCA)产率为98.1%。Ru/NiFe_(2)O_(4)循环使用5次后仍能保持较高的活性,催化剂上活性组分Ru不易浸出,并且催化剂具有磁性能便于与反应溶液分离。为今后工业化催化HMF高效选择性氧化合成FDCA提供参考。展开更多
Biomass conversion to value-added chemicals has received tremendous attention for solving global warming issues and fossil fuel depletion.5-Hydroxymethylfurfural(HMF)is a key bio-based platform molecule to produce man...Biomass conversion to value-added chemicals has received tremendous attention for solving global warming issues and fossil fuel depletion.5-Hydroxymethylfurfural(HMF)is a key bio-based platform molecule to produce many useful organic chemicals by oxidation,hydrogenation,polymerization,and ring-opening reactions.Among all derivatives,the oxidation product 2,5-furandicarboxylic acid(FDCA)is a promising alternative to petroleum-based terephthalic acid for the synthesis of biodegradable plastics.This review analytically discusses the recent progress in the thermocatalytic,electrocatalytic,and photocatalytic oxidation of HMF into FDCA,including catalyst screening,synthesis processes,and reaction mechanism.Rapid fundamental advances may be possible in non-precious metal and metal-free catalysts that are highly efficient under the base-free conditions,and external field-assisted processes like electrochemical or photoelectrochemical cells.展开更多
Solvothermal reaction of 2,5-furandicarboxylic acid （H2FDA） ligand and Ca（NO3）24H2O affords a new coordination polymer, [Ca2（FDA）2（DMAC）（H2O）]n （1）. The structure has been determined by single-crystal X-ra...Solvothermal reaction of 2,5-furandicarboxylic acid （H2FDA） ligand and Ca（NO3）24H2O affords a new coordination polymer, [Ca2（FDA）2（DMAC）（H2O）]n （1）. The structure has been determined by single-crystal X-ray diffraction analyses and further characterized by elemental analyses, IR, powder X-ray diffraction and TGA. Compound I crystallizes in triclinic, space group Pi with a = 9.5387（19）, b = 10.425（2）, c = 11.590（2）A, a = 75.02（3）, fl = 84.80（3）, y = 80.99（3）~, V = 1098.1（4） A3, Dc = 1.492 g/cm^3, C16H15Ca2NO12, Mr = 493.45, F（O00） = 508, p（MoKa）= 0.580 mm-1, Z= 2, R = 0.0436 and wR = 0.0944 for 3865 observed reflections （I〉 2σ（/））, and R --- 0.0595 and wR = 0.1015 for all data. The structure of 1 exhibits a three-dimensional network with layer-pillar structure.展开更多
By using solvothermal method, two new main group metal coordination polymers based on 2,5-furandicarboxylic acid （H2FDA） ligand, [Sr2（FDA）E（H2O）5]n （1） and [Ba4（FDA）4（H2O）10]n （2）, were produced and char...By using solvothermal method, two new main group metal coordination polymers based on 2,5-furandicarboxylic acid （H2FDA） ligand, [Sr2（FDA）E（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） A, β = 107.06（3）°, V = 3482.4（13）A^3, Dc = 2.188 g/cm^3, CIEH14Sr2O15, 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 el with α = 6.8382（14）, b = 10.932（2）, c = 25.571（5） A,α = 94.64（3）, β= 95.41（3）, γ = 107.83（3）°, V= 1799.4（6） A3, Dc = 2.484 g/cm^3, C24H28Ba4O30, Mr = 1345.82, F（000） = 1272,μ（MoKa） = 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 FDA^2- 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.展开更多
Two new complexes [Mn(DHTA)(PLQ)]n(1) and{[Co2(DHTA)(phen)2(H2 O)6]· DHTA}n(2)(H2 DHTA = 2,5-dihydroxy-1,4-benzenedicarboxylic acid, PLQ = 1,10-phenanthroline-5,6-quinone, phen = 1,10-phenanthroline) have been hy...Two new complexes [Mn(DHTA)(PLQ)]n(1) and{[Co2(DHTA)(phen)2(H2 O)6]· DHTA}n(2)(H2 DHTA = 2,5-dihydroxy-1,4-benzenedicarboxylic acid, PLQ = 1,10-phenanthroline-5,6-quinone, phen = 1,10-phenanthroline) have been hydrothermally synthesized and structurally characterized by elemental analysis, IR spectrum, fluorescence spectrum, single-crystal and power X-ray diffraction. Complex 1 exhibits a two-dimensional(2 D) network, which was stabilized through O–H···O hydrogen bonding interactions. Complex 2 shows a zero-dimensional structure, which was further extended into a three-dimensional supramolecular structure through O–H···O hydrogen bonds and π-π interactions.展开更多
Selective oxidation of 5-hydroxymethylfurfual(HMF) to 2,5-furandicarboxylic acid(FDCA) as a bioplastics monomer is efficiently promoted by a simple system without noble-metal and base additives. In this work, graphene...Selective oxidation of 5-hydroxymethylfurfual(HMF) to 2,5-furandicarboxylic acid(FDCA) as a bioplastics monomer is efficiently promoted by a simple system without noble-metal and base additives. In this work, graphene oxide(GO) was first synthesised by an electrochemical method with flexible graphite paper(FGP) as start carbon material, then, nitrogen-doped graphene(NG) layers encapsulated Cu nanoparticles(NPs) was prepared by one-step thermal treatment of GO supported Cu2+ in flowing NH3 atmosphere. Compared with NG supported Cu NPs prepared by the traditional impregnation method, enhanced catalytic activity was achieved over Cu/NG and an FDCA yield of 95.2% was achieved under mild reaction conditions with tert-butylhydroperoxide(t-BuOOH) as the oxidant. Control experiments with different catalysts and different addition procedure of t-BuOOH showed the yield of HMF and various intermediates during reaction. From the changing of intermediates concentrations and reaction rates, a reaction pathway through HMF-DFF-FFCA-FDCA was proposed. This work gives a more convenient, more green,more economical and effective method in encapsulated metal NPs preparation and high selectivity in HMF oxidation to FDCA under mild conditions.展开更多
A cobalt coordination polymer, {[Co2（tdc）2（bimm）2]·（3 DMF）}n, was synthesized based on 2,5-thiophenedicarboxylic acid（H2 tdc） and bis（imidazol-1-yl）methane（bimm） mixed ligands. The asymmetric unit of ...A cobalt coordination polymer, {[Co2（tdc）2（bimm）2]·（3 DMF）}n, was synthesized based on 2,5-thiophenedicarboxylic acid（H2 tdc） and bis（imidazol-1-yl）methane（bimm） mixed ligands. The asymmetric unit of the complex contains two Co2＋） cations, two tdc2-dianions, two neutral bimm ligands, and three free DMF molecules. In the complex, deprotonated tdc2-dianions alternately bridge the adjacent Co2＋ cations to generate chains, which are further connected by the flexible bimm ligands to form a 3 D structure containing adamantanoid-like subunits. In topology, the structure of 1 represents a 4-connected uninodal two-fold interpenetrated dia（66） topology. Moreover, the solid UV-Vis absorption spectra of the complex have also been investigated.展开更多
Terephthalic acid,2,5-furandicarboxylic acid and 1,8-octanediol were adopted as monomers and antimony trioxide as catalyst,and poly(terephthalic acid-2,5-furandicarboxylic acid-1,8-octanediol) copolyesters identified ...Terephthalic acid,2,5-furandicarboxylic acid and 1,8-octanediol were adopted as monomers and antimony trioxide as catalyst,and poly(terephthalic acid-2,5-furandicarboxylic acid-1,8-octanediol) copolyesters identified as PEOT-x,where x is the mole fraction of furandicarboxylic acid in the samples,were synthesized by direct esterification.The molecular structure of the copolyesters was characterized by FTIR and 1H NMR spectroscopy.Gel permeation chromatography (GPC),differential scanning calorimetry (DSC),and thermogravimetric analysis (TGA) were used to characterize the molecular weight,molar mass dispersity,glass transition temperature,and thermal stability of the copolyesters,respectively.The mechanical properties of the samples were also investigated.The number-average molecular weight (M_(n)) of the samples varies from 9 700-18 800 g/mol,and molar mass dispersity (■=M_(w)/M_(n)) from 2.15-3.34.The initial decomposition temperature of the copolyesters is in the 332-356 ℃ range,with maximum decomposition rates at 390-410 ℃,while the glass transition temperature (Tg) varies from 0-33 ℃.Mechanical test shows that PEOT-10 has the highest tensile strength,while PEOT-90 has the largest tensile modulus and elongation at break.The experimental results show that these copolyesters can be synthesized with relatively high molecular weights,good thermal stability,and fair mechanical properties,which makes them excellent replacements for commercial polyesters,such as PET,and these properties can be tuned through the relative amounts of biomass monomer 2,5-furandicarboxylic acid used in the reactions.展开更多
The hydro(solvo)thermal reactions of cobalt powder or its chloride with 2,5- pyridine dicarboxylic acid (H2PYDC) yielded two new complexes: [Co(II)2(PYDC)2(H2O)2- (H2O)4]n 1 and {Co(II)[NH2(CH3)2]2(PYDC)2}n 2. It is o...The hydro(solvo)thermal reactions of cobalt powder or its chloride with 2,5- pyridine dicarboxylic acid (H2PYDC) yielded two new complexes: [Co(II)2(PYDC)2(H2O)2- (H2O)4]n 1 and {Co(II)[NH2(CH3)2]2(PYDC)2}n 2. It is observed that the reactive solvents result in different connectivity modes of ligand and diverse dimensional extension of crystal structures. The correlation between structure and magnetic property will be discussed in this paper. Crystal data for 1: space group P1, a = 7.0419(17), b = 8.937(2), c = 9.6182(19) ?, α = 91.532(4), β = 99.869(10), γ = 107.889(11)o, V = 565.5(2) ?3, Z = 1, Dc = 1.845 g/cm3, μ = 1.56 mm-1, F(000) = 322 , R = 0.0505 and wR = 0.1580; and those for 2: space group C2/c, a = 14.9075(6), b = 8.2523(3), c = 16.9643(2) ?, β = 100.982(2)o, V = 2048.75(11) ?3, Z = 4, Dc = 1.560 g/cm3, μ = 0.892 mm-1, F(000) = 996, R = 0.0443 and wR = 0.1134.展开更多
基金Supported by the National Natural Science Foundation of China(21031002 and 51073079)the Fundamental Research Funds for the Central Universitiesthe Application and Research in Cutting-edge Technologies in Tianjin Technology Projects in General(K11JCYBJC11100)
文摘Two new Cu（II） coordination polymers, [Cu（FDA）（BPY）（H20）]n （1） and {[Cu（FDA）（BPY）（H2O）].2H2O}n （2） （H2FDA = 2,5-furandicarboxylic acid, BPY = 2,2＇-bipyridine）, have been synthesized and structurally characterized by single-crystal X-ray diffraction as well as elemental analysis and IR. Compound 1 crystallizes in monoclinic, space group P21/c, with a = 7.5915（15）, b = 8.4050（17）, c = 24.204（6） A, β = 99.05（3）°, V= 1525.1（6） A3, Dc = 1.706 g/crn3, C16HI2CuN206, Mr = 391.82, F（000） = 796, μ（MoKa） = 1.470 mm-l, Z = 4, R = 0.0633 and wR = 0.1059 for 2389 observed reflections （1 〉 2a（I））, R = 0.0738, and wR = 0.1098 for all data. Complex 2 belongs to triclinic space group PI with a = 8.8660（18）, b = 8.9112（18）, c = 12.525（3） A, a = 88.41（3）, β = 69.38（3）, γ = 66.95（3）°, V = 845.2（3） A3, Dc = 1.681 g/cm3, CI6HI6CuN2Os, Mr. = 427.85, F（000） = 438, μ（MoKα） = 1.342 mm-1, Z = 2, R = 0.0290 and wR = 0.0690 for 2767 observed reflections （I 〉 2σ（I））, R = 0.0329 and wR = 0.0706 for all data. Complexes 1 and 2 are both coordination polymers with one-dimensional chain structures bridged by the protonated FDA ligands, which are assembled into three-dimensional supramolecular structures through hydrogen bonding interactions and π-π packing interactions between the chains.
文摘采用水热-煅烧法制备了磁性镍铁尖晶石载体NiFe_(2)O_(4),再采用浸渍-还原法在载体上负载Ru纳米粒子制备Ru/NiFe_(2)O_(4)催化剂。采用X射线衍射(XRD)、N2吸附-脱附(BET)、NH3程序升温脱附(NH3-TPD)、H_(2)程序升温还原(H_(2)-TPR)、X射线光电子能谱(XPS)和电感耦合等离子体发射光谱(ICP-OES)测试对催化剂进行表征分析。结果表明,Ru/NiFe_(2)O_(4)催化剂表面氧物种丰富,相较于载体,负载Ru后催化剂比表面积和表面酸量增加,Ru与载体存在相互作用,这可能是催化剂高活性和高稳定性的关键。将催化剂用于5-羟甲基糠醛(HMF)的选择性氧化,负载Ru后,催化剂催化活性显著提升。对反应条件进行优化,在添加0.08 g KHCO3,氧化剂O2压力为1 MPa,反应温度为80℃,使用0.1 g Ru/NiFe_(2)O_(4)催化剂,在水溶液中反应12 h HMF能完全转化,2,5-呋喃二甲酸(FDCA)产率为98.1%。Ru/NiFe_(2)O_(4)循环使用5次后仍能保持较高的活性,催化剂上活性组分Ru不易浸出,并且催化剂具有磁性能便于与反应溶液分离。为今后工业化催化HMF高效选择性氧化合成FDCA提供参考。
基金supported by Chinese Academy of Sciences(QYZDB-SSW-JSC037)Natural Science Foundation of Zhejiang Province(LY19B030003,LQ19B060002)+1 种基金Ningbo Science and Technology Bureau(2018B10056,2019B10096)Fujian Institute of Innovation(FJCXY18020202)。
文摘Biomass conversion to value-added chemicals has received tremendous attention for solving global warming issues and fossil fuel depletion.5-Hydroxymethylfurfural(HMF)is a key bio-based platform molecule to produce many useful organic chemicals by oxidation,hydrogenation,polymerization,and ring-opening reactions.Among all derivatives,the oxidation product 2,5-furandicarboxylic acid(FDCA)is a promising alternative to petroleum-based terephthalic acid for the synthesis of biodegradable plastics.This review analytically discusses the recent progress in the thermocatalytic,electrocatalytic,and photocatalytic oxidation of HMF into FDCA,including catalyst screening,synthesis processes,and reaction mechanism.Rapid fundamental advances may be possible in non-precious metal and metal-free catalysts that are highly efficient under the base-free conditions,and external field-assisted processes like electrochemical or photoelectrochemical cells.
基金supported by the science and technology research projects of Tianjin Health Bureau (W11KG127)
文摘Solvothermal reaction of 2,5-furandicarboxylic acid （H2FDA） ligand and Ca（NO3）24H2O affords a new coordination polymer, [Ca2（FDA）2（DMAC）（H2O）]n （1）. The structure has been determined by single-crystal X-ray diffraction analyses and further characterized by elemental analyses, IR, powder X-ray diffraction and TGA. Compound I crystallizes in triclinic, space group Pi with a = 9.5387（19）, b = 10.425（2）, c = 11.590（2）A, a = 75.02（3）, fl = 84.80（3）, y = 80.99（3）~, V = 1098.1（4） A3, Dc = 1.492 g/cm^3, C16H15Ca2NO12, Mr = 493.45, F（O00） = 508, p（MoKa）= 0.580 mm-1, Z= 2, R = 0.0436 and wR = 0.0944 for 3865 observed reflections （I〉 2σ（/））, and R --- 0.0595 and wR = 0.1015 for all data. The structure of 1 exhibits a three-dimensional network with layer-pillar structure.
基金supported by URT program of Beijing Institute of Petrochemical Technology(2015J00058 and 2015J00056)
文摘By using solvothermal method, two new main group metal coordination polymers based on 2,5-furandicarboxylic acid （H2FDA） ligand, [Sr2（FDA）E（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） A, β = 107.06（3）°, V = 3482.4（13）A^3, Dc = 2.188 g/cm^3, CIEH14Sr2O15, 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 el with α = 6.8382（14）, b = 10.932（2）, c = 25.571（5） A,α = 94.64（3）, β= 95.41（3）, γ = 107.83（3）°, V= 1799.4（6） A3, Dc = 2.484 g/cm^3, C24H28Ba4O30, Mr = 1345.82, F（000） = 1272,μ（MoKa） = 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 FDA^2- 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.
基金supported by the Science and Technology development plan of Jilin Province(2015052006JH)
文摘Two new complexes [Mn(DHTA)(PLQ)]n(1) and{[Co2(DHTA)(phen)2(H2 O)6]· DHTA}n(2)(H2 DHTA = 2,5-dihydroxy-1,4-benzenedicarboxylic acid, PLQ = 1,10-phenanthroline-5,6-quinone, phen = 1,10-phenanthroline) have been hydrothermally synthesized and structurally characterized by elemental analysis, IR spectrum, fluorescence spectrum, single-crystal and power X-ray diffraction. Complex 1 exhibits a two-dimensional(2 D) network, which was stabilized through O–H···O hydrogen bonding interactions. Complex 2 shows a zero-dimensional structure, which was further extended into a three-dimensional supramolecular structure through O–H···O hydrogen bonds and π-π interactions.
基金the National Natural Science Foundation of China(NNSFC)(21805145&U1610108)the Department of Science and Technology of Shandong Province(ZR2019BB068)+2 种基金the Department of Science and Technology of Shanxi Province(201705D211001)Scientific and Technological Innovation Programs of High Education Institutions in Shanxi(201802001-1)the Department of Human Resource and Social Security of Shanxi Province(Y6SW9613B1)。
文摘Selective oxidation of 5-hydroxymethylfurfual(HMF) to 2,5-furandicarboxylic acid(FDCA) as a bioplastics monomer is efficiently promoted by a simple system without noble-metal and base additives. In this work, graphene oxide(GO) was first synthesised by an electrochemical method with flexible graphite paper(FGP) as start carbon material, then, nitrogen-doped graphene(NG) layers encapsulated Cu nanoparticles(NPs) was prepared by one-step thermal treatment of GO supported Cu2+ in flowing NH3 atmosphere. Compared with NG supported Cu NPs prepared by the traditional impregnation method, enhanced catalytic activity was achieved over Cu/NG and an FDCA yield of 95.2% was achieved under mild reaction conditions with tert-butylhydroperoxide(t-BuOOH) as the oxidant. Control experiments with different catalysts and different addition procedure of t-BuOOH showed the yield of HMF and various intermediates during reaction. From the changing of intermediates concentrations and reaction rates, a reaction pathway through HMF-DFF-FFCA-FDCA was proposed. This work gives a more convenient, more green,more economical and effective method in encapsulated metal NPs preparation and high selectivity in HMF oxidation to FDCA under mild conditions.
基金supported by the Natural Science Foundation of Henan Province(172102310333)
文摘A cobalt coordination polymer, {[Co2（tdc）2（bimm）2]·（3 DMF）}n, was synthesized based on 2,5-thiophenedicarboxylic acid（H2 tdc） and bis（imidazol-1-yl）methane（bimm） mixed ligands. The asymmetric unit of the complex contains two Co2＋） cations, two tdc2-dianions, two neutral bimm ligands, and three free DMF molecules. In the complex, deprotonated tdc2-dianions alternately bridge the adjacent Co2＋ cations to generate chains, which are further connected by the flexible bimm ligands to form a 3 D structure containing adamantanoid-like subunits. In topology, the structure of 1 represents a 4-connected uninodal two-fold interpenetrated dia（66） topology. Moreover, the solid UV-Vis absorption spectra of the complex have also been investigated.
基金Funded by the Program (BG20190227001) of High-end Foreign Experts of the State Administration of Foreign Experts Affairs (SAFEA)the 2021 Innovative Training Program for College Students in Hubei Province。
文摘Terephthalic acid,2,5-furandicarboxylic acid and 1,8-octanediol were adopted as monomers and antimony trioxide as catalyst,and poly(terephthalic acid-2,5-furandicarboxylic acid-1,8-octanediol) copolyesters identified as PEOT-x,where x is the mole fraction of furandicarboxylic acid in the samples,were synthesized by direct esterification.The molecular structure of the copolyesters was characterized by FTIR and 1H NMR spectroscopy.Gel permeation chromatography (GPC),differential scanning calorimetry (DSC),and thermogravimetric analysis (TGA) were used to characterize the molecular weight,molar mass dispersity,glass transition temperature,and thermal stability of the copolyesters,respectively.The mechanical properties of the samples were also investigated.The number-average molecular weight (M_(n)) of the samples varies from 9 700-18 800 g/mol,and molar mass dispersity (■=M_(w)/M_(n)) from 2.15-3.34.The initial decomposition temperature of the copolyesters is in the 332-356 ℃ range,with maximum decomposition rates at 390-410 ℃,while the glass transition temperature (Tg) varies from 0-33 ℃.Mechanical test shows that PEOT-10 has the highest tensile strength,while PEOT-90 has the largest tensile modulus and elongation at break.The experimental results show that these copolyesters can be synthesized with relatively high molecular weights,good thermal stability,and fair mechanical properties,which makes them excellent replacements for commercial polyesters,such as PET,and these properties can be tuned through the relative amounts of biomass monomer 2,5-furandicarboxylic acid used in the reactions.
基金Financially support by NNSFC (No. 20031020) NSF of Fujian Province and the Key Project from CAS
文摘The hydro(solvo)thermal reactions of cobalt powder or its chloride with 2,5- pyridine dicarboxylic acid (H2PYDC) yielded two new complexes: [Co(II)2(PYDC)2(H2O)2- (H2O)4]n 1 and {Co(II)[NH2(CH3)2]2(PYDC)2}n 2. It is observed that the reactive solvents result in different connectivity modes of ligand and diverse dimensional extension of crystal structures. The correlation between structure and magnetic property will be discussed in this paper. Crystal data for 1: space group P1, a = 7.0419(17), b = 8.937(2), c = 9.6182(19) ?, α = 91.532(4), β = 99.869(10), γ = 107.889(11)o, V = 565.5(2) ?3, Z = 1, Dc = 1.845 g/cm3, μ = 1.56 mm-1, F(000) = 322 , R = 0.0505 and wR = 0.1580; and those for 2: space group C2/c, a = 14.9075(6), b = 8.2523(3), c = 16.9643(2) ?, β = 100.982(2)o, V = 2048.75(11) ?3, Z = 4, Dc = 1.560 g/cm3, μ = 0.892 mm-1, F(000) = 996, R = 0.0443 and wR = 0.1134.
