The addition of pyridine-2-carboxaldoxime or α-furildioxime to dialkyl acety lenedicarboxy lates under neutral conditions in the presence of alkyl isocyanides leads to ketenimines and bis(ketenimines) in good yields.
A new complex Mn(Htpc)2(H2O)2(1, Htpc = 5-(trifluoromethyl)pyridine-2-carboxylic acid) has been synthesized and characterized by elemental analysis, IR, TG and single-crystal X-ray diffraction. 1 belongs to triclinic ...A new complex Mn(Htpc)2(H2O)2(1, Htpc = 5-(trifluoromethyl)pyridine-2-carboxylic acid) has been synthesized and characterized by elemental analysis, IR, TG and single-crystal X-ray diffraction. 1 belongs to triclinic system, space group P■ with a = 5.0885(10), b = 6.5574(13), c = 14.016(3) ?, β = 90.67(3)o, V = 436.34(17) ?3, Z = 1, Dc = 1.793 g·cm-3, μ = 0.855 mm-1, Mr = 471.18, F(000) = 235, the final R = 0.0454 and wR = 0.1134 for 1998 observed reflections with I > 2σ(I). The Mn(Ⅱ) ion is coordinated by two N and two O atoms from two Htpc as well as two O atoms from two coordinated water molecules, forming a 0D motif with distorted octahedral coordinate geometry. The adjacent 0D units are linked into 1D chains through hydrogen bond O(1W)–H(1 WB)···O(2), and via the O(1 W)–H(1 WA)···O(1) hydrogen bond the neighboring 1D chains are connected into a 2D supramolecular layer. Moreover, the interactions between the ligand and its complex with CT-DNA were studied by EtBr fluorescence probe, which suggested that these compounds bind to CT-DNA through an intercalation mode. The binding constants were 0.41 and 0.64 for Htpc and complex 1, respectively. It indicates that the interaction between complex 1 and CT-DNA is stronger than Htpc.展开更多
Two novel ligands named 4-styrylpyridine-2,6-dicarboxylic acid (4-SPDA) and 4-(4-(2-(2, 6-dicarboxypyridin-4-yl)- vinyl)styryl)pyridine-2,6-dicarboxylic acid(DSPDA) and their complexes with Tb(Ⅲ) were synthesized and...Two novel ligands named 4-styrylpyridine-2,6-dicarboxylic acid (4-SPDA) and 4-(4-(2-(2, 6-dicarboxypyridin-4-yl)- vinyl)styryl)pyridine-2,6-dicarboxylic acid(DSPDA) and their complexes with Tb(Ⅲ) were synthesized and characterized by infrared spectrometry, 1H nuclear magnetic resonance, elemental analysis and gas chromatograph-mass spectrometry. The ligand synthetic route was optimized. The fluorescence properties of the complex in solid state, in different kind of solvents and in solutions with different pH values were investigated in detail. The results show that the yields of DSPDA and 4-SPDA reach over 78% by Wittig-Horner reaction and other eight pyridine-2, 6-dicarboxylic acid derivatives with different substituents on pyridine ring, and their complexes with Tb(Ⅲ) are also obtained. The fluorescence intensities of the complexes with electron-donating groups are more intense than those of the complexes with electron-withdrawing groups on pyridine ring; fluorescence intensities of the complexes are the strongest in neutral solution (pH=7), and the less the dipole moment of solvent molecule is, the stronger the fluorescence intensity is. It is found that the two ligands (4-APDA and DSPDA) are the good sensitizers for Tb(Ⅲ) ion.展开更多
Protonating the pyridine rings of poly(pyridine-2,5-diyl) with dodecybenzenesulfonic acid and camphorsulphonic acid produces polymer materials which can be dissolved in chloroform (in contrast to the unprotonated poly...Protonating the pyridine rings of poly(pyridine-2,5-diyl) with dodecybenzenesulfonic acid and camphorsulphonic acid produces polymer materials which can be dissolved in chloroform (in contrast to the unprotonated polymer, which can only be dissolved in strong acids such as formic acid) and allows mixing the protonated polymers with other chloroform soluble conju- gated polymers for use in electronic devices. The protonating behavior of poly(pyridine-2,5-diyl) with two kinds of surfactants is different in some levels. Dodecybenzenesulfonic acid has higher protonating ability than camphorsulphonic acid.展开更多
The Schiff base pyridine-2-carboxaldehyde-4-aminoantipyrine (CI7H16N4O 1) and its perchlorate (C17H17N4O·ClO4 2) have been prepared and characterized by elemental analysis, IR spectra and single-crystal X-ray...The Schiff base pyridine-2-carboxaldehyde-4-aminoantipyrine (CI7H16N4O 1) and its perchlorate (C17H17N4O·ClO4 2) have been prepared and characterized by elemental analysis, IR spectra and single-crystal X-ray crystallography analysis. Both 1 and 2 crystallize in the monoclinic system, space group P21/c. For 1, a = 8.6820(12), b = 24.934(3), c = 7.0064(10) A,, β= 97.942(3)°, V = 1502.2(4) A^3, Z = 4, Dc = 1.293 g/cm^3, F(000) = 616,μ = 0.084 mm^-1, the final R = 0.0592 and wR = 0.1244. For 2, a = 5.9302(2), b = 20.347(7), c = 14.663(6) A, β= 90.200(9)°, V= 1769.201) A^3, Z = 4, Dc = 1.475 g/cm^3, F(000) = 816, μ = 0.254 mm^-1, the final R = 0.0533 and wR = 0.0819. As expected, both molecular structures of 1 and 2 adopt a trans configuration about the central C=N double bond. 2 is an ionic compound with the protonation at N(1) of pyridine-2-carboxaldehyde-4- aminoantipyrine.展开更多
The reaction mechanism of 2-methoxybenzaldehyde, 4-bromo-indanone, malononitrile and ammonium acetate one-pot to form 6-(2-methoxyphenyl)-2-amino-6-bromo-5 Hindeno[1,2-b]pyridine-3-carbonitrile was studied by densit...The reaction mechanism of 2-methoxybenzaldehyde, 4-bromo-indanone, malononitrile and ammonium acetate one-pot to form 6-(2-methoxyphenyl)-2-amino-6-bromo-5 Hindeno[1,2-b]pyridine-3-carbonitrile was studied by density functional theory. The geometries of the reactants, transition states, intermediates and products were optimized at the PW91/DNP level. Vibration analysis was carried out to confirm the transition state structure. Reaction pathways were investigated in this study. The result indicates that the reaction Re→ TSB1→IMB1→ TSB2→ IMB2→TSB3→IMB3→TSB4→IMB4→TSB5→IMB5→TSB6→IMB6→TSB7→IMB7→ TSB8→IMB8→TSB9→IMB9→P2 is the main pathway, the activation energy of which is the lowest. The dominant product predicted theoretically is in agreement with the experiment results.展开更多
The synthesis of the bis-isoxazolyl-1,2,5,6-tetrahydro pyridine-3-carboxylates is achieved in high yield without the production of toxic waste products by using room temperature ionic liquid (RTILs) triethyl ammonium ...The synthesis of the bis-isoxazolyl-1,2,5,6-tetrahydro pyridine-3-carboxylates is achieved in high yield without the production of toxic waste products by using room temperature ionic liquid (RTILs) triethyl ammonium acetate (TEAA). The RTIL TEAA played the dual role of efficient green solvent as well as recyclable catalyst.展开更多
The title complex was obtained by reactions of [Mo(CO)_3(MeCN)_3] with [CuBr(pySH)(PPh_3)_2]or directly with pySH and PPh_3. The latter method can be used to synthesize the corresponding tungsten complex [W_2(CO)_4(μ...The title complex was obtained by reactions of [Mo(CO)_3(MeCN)_3] with [CuBr(pySH)(PPh_3)_2]or directly with pySH and PPh_3. The latter method can be used to synthesize the corresponding tungsten complex [W_2(CO)_4(μ-pyS)_2(PPh_3)_2].The molecular structure of the title compound was determined by X-ray diffraction method.展开更多
A series of new Schiff bases derived from 2-aminopyridenes and various aromatic aldehydes have been synthesized and thoroughly investigated by 1H and 13C NMR spectroscopy. The imines were found to exist as only a sing...A series of new Schiff bases derived from 2-aminopyridenes and various aromatic aldehydes have been synthesized and thoroughly investigated by 1H and 13C NMR spectroscopy. The imines were found to exist as only a single E-isomer at ambient temperature. Interestingly, 1H- and 13C-NMR chemical shifts of the (CH=N) amino group are affected by the type of substituent group (X) on the aryl ring. Furthermore UV and IR Spectra of some of the title compounds are also reported.展开更多
A novel terbium(III) coordination polymer [Tb(C7H3NO4)(C6H4NO2)(H2O)] was successfully synthesized hydrothermally and characterized by single-crystal X-ray diffraction. The complex is of monoclinic, space group P21/c ...A novel terbium(III) coordination polymer [Tb(C7H3NO4)(C6H4NO2)(H2O)] was successfully synthesized hydrothermally and characterized by single-crystal X-ray diffraction. The complex is of monoclinic, space group P21/c with a = 9.2252(11), b = 14.1477(16), c = 10.5134(12) A, β = 95.770(2)°, V = 1365.2(3) A3, Z = 4, Dc = 2.248 g·cm-3, F(000) = 880, the final R = 0.0176 and w R = 0.0411 for 2149 observed reflections with I 】 2σ(I). The complex is extended into a three-dimensional network structure with 24-atom rings which are composed of Tb, C and O atoms. The complex displays green fluorescence emission in the solid state at room temperature, which corresponds to 5D4 → 7F5 transition of the Tb(III) ion.展开更多
The title compound (Z)-1-(3-fluorobenzyl)-5-((3-fluorobenzylimino)(2-hydroxy-4- methoxyphenyl)methyl)pyridin-2(1H)-one (C27H22F2N2O3,Mr = 460.47) was synthesized and crystallized. The crystal belongs to ...The title compound (Z)-1-(3-fluorobenzyl)-5-((3-fluorobenzylimino)(2-hydroxy-4- methoxyphenyl)methyl)pyridin-2(1H)-one (C27H22F2N2O3,Mr = 460.47) was synthesized and crystallized. The crystal belongs to the triclinic system,space group P1 with a = 9.951(6),b = 10.059(6),c = 12.927(7)A,α = 109.828(7),β = 102.304(7),γ = 104.898(7)°,Z = 2,V = 1110.2(11)A^3,Dc =1.377 Mg/m^3,μ(MoKα) = 0.102 mm^-1,F(000) = 480,the final R = 0.0449 and Rw = 0.1250 for 4595 observed reflections (I 〉 2σ(I)). X-ray analysis reveals that both m-fluorobenzyl groups are diorientationally disordered because of the rotation of C–C single bond which was represented as F(1),F(2) and F(1'),F(2'). The diorientational disorder was refined and gave the occupancies of 0.665(4) and 0.335(4) for F(1) and F(1'),0.631(3) and 0.369(3) for F(2) and F(2'). Hydrogen bonds existing in the cell link different components to stabilize the crystal structure. The active data proved that the title compound has good anti-HBV activity.展开更多
Cobalt and nickel complexes (la-ld and 2a-2d, respectively) supported by 2-imidate-pyridine ligands were synthesized and used for 1,3-butadiene polymerization. The complexes were characterized by IR and element anal...Cobalt and nickel complexes (la-ld and 2a-2d, respectively) supported by 2-imidate-pyridine ligands were synthesized and used for 1,3-butadiene polymerization. The complexes were characterized by IR and element analysis, and complex la was further characterized by single-crystal X-ray diffraction. The solid state structure of complex la displayed a distorted tetrahedral geometry. Upon activation with ethylaluminum sesquichloride (EASC), all the complexes showed high activities toward 1,3-butadiene polymerization. The cobalt complexes produced polymers with high cis-1,4 contents and high molecular weights, while the nickel complexes displayed low cis-l,4 selectivity and the resulting polymers had low molecular weights. The catalytic activities of the complexes highly depended on the ligand structure. With the increment of polymerization temperature, the cis-1,4 content and the molecular weight of the resulting polymer decreased.展开更多
The copper(Ⅱ) complexes of pyridine-3-carboxylic acid (nicotinic acid) and pyridine-2-carboxylic acid (isonicotinic acid) were synthesized, and their structures were characterized by elemental analysis, infrare...The copper(Ⅱ) complexes of pyridine-3-carboxylic acid (nicotinic acid) and pyridine-2-carboxylic acid (isonicotinic acid) were synthesized, and their structures were characterized by elemental analysis, infrared spectrum, powder X-ray diffraction and so on. The results show that under experimental conditions, the ligands of synthesized copper nicotinate and copper isonicotinate are coordinated simultaneity with copper(Ⅱ) via the nitrogen of pyridine group and an oxygen of carboxylic acid group to form bidentate chelates. The crystal of copper nicotinate with two six-membered chelate rings belongs to monoclinic system, while that of copper isonicotinate having two five-membered chelate rings is of triclinic system. The tests show that the biological activities, such as the improvement of feed utilization, growth, anti-oxidation ability of organism and disease-resistant power, are different when copper nicotinate, copper inicotinate, copper-lysine chelate, copper-methionine chelate and copper sulphate are added in pig's feed, respectively. Due to its higher biological activity, less pollution and lower toxicity, copper nicotinate has wide potential applications as a feed additive.展开更多
2-(pyridine-2-yl)-N-p-chlorohydrazinecarbothioamide (HCPTS) was synthesized, characterized and successfully applied for the preconcentration of Cu(II), Ni(II), Zn(II), Cd(II), Co(II), Pb(II), Fe(II), and Hg(II) in wat...2-(pyridine-2-yl)-N-p-chlorohydrazinecarbothioamide (HCPTS) was synthesized, characterized and successfully applied for the preconcentration of Cu(II), Ni(II), Zn(II), Cd(II), Co(II), Pb(II), Fe(II), and Hg(II) in water, blood, and urine samples prior to graphite furnace atomic absorption determination (GFAAS);Hg was determined by cold vapor technique. Under the optimum experimental conditions (i.e. pH = 8, 10–4 M of HCPTS, 0.05% w/v of Triton X-114), calibration graphs were linear in the range of 0.02 to 200 ng?mL–1 for Co(II), Cd(II), Pb(II) and Ni(II);0.03 to 200 ng?mL–1 for Cu(II);0.07 to 200 ng?mL–1 for Fe(II) and Zn(II) and 0.02 to 150 ng?mL–1 for Hg(II). The enrichment factors were 43, 51, 41, 46, 54, 40, 45 and 52 for Cu(II), Ni(II),Zn (II), Cd(II), Co(II), Pb(II), Fe(II), and Hg(II), respectively. The limit of detection were found to be 0.019, 0.094, 0.0514, 0.052, 0.0165, 0.047, 0.068 and 0.041 ng?mL–1 for Cu(II), Ni(II), Zn(II), Cd(II), Co(II), Pb(II), Fe(II), and Hg(II), respectively. The developed method was applied to the determination of these metal ions in water, blood and urine samples with satisfactory results.展开更多
A novel and green method for the synthesis of dimethyl pyridine-3,5-dicarboxylate has been developed. It is PdCl2-catalyzed heterocyclotrimerization of methyl acrylate with urea in methanol/supercritical carbon dioxid...A novel and green method for the synthesis of dimethyl pyridine-3,5-dicarboxylate has been developed. It is PdCl2-catalyzed heterocyclotrimerization of methyl acrylate with urea in methanol/supercritical carbon dioxide. The target compound was obtained with a 75% isolated yield under the optimized con-ditions.展开更多
A new luminescent compound, {[Eu3(L)4(H2 O)8]·(NO3)·4 H2 O}n(1, H2 L = 2-(pyridine-3-yl)-imidazole-4,5-dicarboxylic acid) has been solvothermally synthesized and structurally characterized by eleme...A new luminescent compound, {[Eu3(L)4(H2 O)8]·(NO3)·4 H2 O}n(1, H2 L = 2-(pyridine-3-yl)-imidazole-4,5-dicarboxylic acid) has been solvothermally synthesized and structurally characterized by elemental analyses, IR and single-crystal X-ray diffraction. 1 crystallizes in monoclinic, space group C2/c with a = 21.0183(19), b = 9.5227(6), c = 28.227(3) ?, β = 106.885(5)o, V = 5406.1(8) ?3, Dc = 2.038 g/cm3, μ = 3.358 mm-1, Mr = 1658.76, F(000) = 3247, Z = 4, the final R = 0.0488, wR = 0.1195 and S = 1.075. The deprotonated L ligand employs a μ4-bridge to coordinate with three Eu(Ⅲ) ion, forming a wave-like(3,4)-connected 2 D structure. The existence of π···π interaction between the pyridine rings of L ligands leads to an infinite 3 D network. Furthermore, the thermal analysis, powder diffraction and solid-state photoluminescent properties of compound 1 have also been investigated.展开更多
文摘The addition of pyridine-2-carboxaldoxime or α-furildioxime to dialkyl acety lenedicarboxy lates under neutral conditions in the presence of alkyl isocyanides leads to ketenimines and bis(ketenimines) in good yields.
基金Supported by the Scientific Research Foundation of Higher Education Institutions of Ningxia(No.NGY2017004)the National Natural Science Foundation of China(Nos.21763022 and 50564043)the Major Innovation Projects for Building First-class Universities in China’s Western Region(No.ZKZD2017003)
文摘A new complex Mn(Htpc)2(H2O)2(1, Htpc = 5-(trifluoromethyl)pyridine-2-carboxylic acid) has been synthesized and characterized by elemental analysis, IR, TG and single-crystal X-ray diffraction. 1 belongs to triclinic system, space group P■ with a = 5.0885(10), b = 6.5574(13), c = 14.016(3) ?, β = 90.67(3)o, V = 436.34(17) ?3, Z = 1, Dc = 1.793 g·cm-3, μ = 0.855 mm-1, Mr = 471.18, F(000) = 235, the final R = 0.0454 and wR = 0.1134 for 1998 observed reflections with I > 2σ(I). The Mn(Ⅱ) ion is coordinated by two N and two O atoms from two Htpc as well as two O atoms from two coordinated water molecules, forming a 0D motif with distorted octahedral coordinate geometry. The adjacent 0D units are linked into 1D chains through hydrogen bond O(1W)–H(1 WB)···O(2), and via the O(1 W)–H(1 WA)···O(1) hydrogen bond the neighboring 1D chains are connected into a 2D supramolecular layer. Moreover, the interactions between the ligand and its complex with CT-DNA were studied by EtBr fluorescence probe, which suggested that these compounds bind to CT-DNA through an intercalation mode. The binding constants were 0.41 and 0.64 for Htpc and complex 1, respectively. It indicates that the interaction between complex 1 and CT-DNA is stronger than Htpc.
基金Project(20761002) supported by the National Natural Science Foundation of China
文摘Two novel ligands named 4-styrylpyridine-2,6-dicarboxylic acid (4-SPDA) and 4-(4-(2-(2, 6-dicarboxypyridin-4-yl)- vinyl)styryl)pyridine-2,6-dicarboxylic acid(DSPDA) and their complexes with Tb(Ⅲ) were synthesized and characterized by infrared spectrometry, 1H nuclear magnetic resonance, elemental analysis and gas chromatograph-mass spectrometry. The ligand synthetic route was optimized. The fluorescence properties of the complex in solid state, in different kind of solvents and in solutions with different pH values were investigated in detail. The results show that the yields of DSPDA and 4-SPDA reach over 78% by Wittig-Horner reaction and other eight pyridine-2, 6-dicarboxylic acid derivatives with different substituents on pyridine ring, and their complexes with Tb(Ⅲ) are also obtained. The fluorescence intensities of the complexes with electron-donating groups are more intense than those of the complexes with electron-withdrawing groups on pyridine ring; fluorescence intensities of the complexes are the strongest in neutral solution (pH=7), and the less the dipole moment of solvent molecule is, the stronger the fluorescence intensity is. It is found that the two ligands (4-APDA and DSPDA) are the good sensitizers for Tb(Ⅲ) ion.
文摘Protonating the pyridine rings of poly(pyridine-2,5-diyl) with dodecybenzenesulfonic acid and camphorsulphonic acid produces polymer materials which can be dissolved in chloroform (in contrast to the unprotonated polymer, which can only be dissolved in strong acids such as formic acid) and allows mixing the protonated polymers with other chloroform soluble conju- gated polymers for use in electronic devices. The protonating behavior of poly(pyridine-2,5-diyl) with two kinds of surfactants is different in some levels. Dodecybenzenesulfonic acid has higher protonating ability than camphorsulphonic acid.
基金supported by the NSF of Guangxi Province (No. 0575046, 0575049)the Program for New Century Ten-Hundred-Thousand Excellent Talents of Guangxi (No. 2003223)+1 种基金the National Natural Science Foundation of China (No. 20361002, 30460153) as well as TRAPOYTNCET-04-0836 of Chinese Ministry of Education
文摘The Schiff base pyridine-2-carboxaldehyde-4-aminoantipyrine (CI7H16N4O 1) and its perchlorate (C17H17N4O·ClO4 2) have been prepared and characterized by elemental analysis, IR spectra and single-crystal X-ray crystallography analysis. Both 1 and 2 crystallize in the monoclinic system, space group P21/c. For 1, a = 8.6820(12), b = 24.934(3), c = 7.0064(10) A,, β= 97.942(3)°, V = 1502.2(4) A^3, Z = 4, Dc = 1.293 g/cm^3, F(000) = 616,μ = 0.084 mm^-1, the final R = 0.0592 and wR = 0.1244. For 2, a = 5.9302(2), b = 20.347(7), c = 14.663(6) A, β= 90.200(9)°, V= 1769.201) A^3, Z = 4, Dc = 1.475 g/cm^3, F(000) = 816, μ = 0.254 mm^-1, the final R = 0.0533 and wR = 0.0819. As expected, both molecular structures of 1 and 2 adopt a trans configuration about the central C=N double bond. 2 is an ionic compound with the protonation at N(1) of pyridine-2-carboxaldehyde-4- aminoantipyrine.
基金Project supported by the Scientific and Technological Research Program of Chongqing Municipal Education Commission(KJ1601215,KJ15012002)the Ministry of Education “Chunhui Plan”(Z2016177)
文摘The reaction mechanism of 2-methoxybenzaldehyde, 4-bromo-indanone, malononitrile and ammonium acetate one-pot to form 6-(2-methoxyphenyl)-2-amino-6-bromo-5 Hindeno[1,2-b]pyridine-3-carbonitrile was studied by density functional theory. The geometries of the reactants, transition states, intermediates and products were optimized at the PW91/DNP level. Vibration analysis was carried out to confirm the transition state structure. Reaction pathways were investigated in this study. The result indicates that the reaction Re→ TSB1→IMB1→ TSB2→ IMB2→TSB3→IMB3→TSB4→IMB4→TSB5→IMB5→TSB6→IMB6→TSB7→IMB7→ TSB8→IMB8→TSB9→IMB9→P2 is the main pathway, the activation energy of which is the lowest. The dominant product predicted theoretically is in agreement with the experiment results.
文摘The synthesis of the bis-isoxazolyl-1,2,5,6-tetrahydro pyridine-3-carboxylates is achieved in high yield without the production of toxic waste products by using room temperature ionic liquid (RTILs) triethyl ammonium acetate (TEAA). The RTIL TEAA played the dual role of efficient green solvent as well as recyclable catalyst.
文摘The title complex was obtained by reactions of [Mo(CO)_3(MeCN)_3] with [CuBr(pySH)(PPh_3)_2]or directly with pySH and PPh_3. The latter method can be used to synthesize the corresponding tungsten complex [W_2(CO)_4(μ-pyS)_2(PPh_3)_2].The molecular structure of the title compound was determined by X-ray diffraction method.
文摘A series of new Schiff bases derived from 2-aminopyridenes and various aromatic aldehydes have been synthesized and thoroughly investigated by 1H and 13C NMR spectroscopy. The imines were found to exist as only a single E-isomer at ambient temperature. Interestingly, 1H- and 13C-NMR chemical shifts of the (CH=N) amino group are affected by the type of substituent group (X) on the aryl ring. Furthermore UV and IR Spectra of some of the title compounds are also reported.
基金financially supported by Foundation of Fujian Educational Committee(JA14348)
文摘A novel terbium(III) coordination polymer [Tb(C7H3NO4)(C6H4NO2)(H2O)] was successfully synthesized hydrothermally and characterized by single-crystal X-ray diffraction. The complex is of monoclinic, space group P21/c with a = 9.2252(11), b = 14.1477(16), c = 10.5134(12) A, β = 95.770(2)°, V = 1365.2(3) A3, Z = 4, Dc = 2.248 g·cm-3, F(000) = 880, the final R = 0.0176 and w R = 0.0411 for 2149 observed reflections with I 】 2σ(I). The complex is extended into a three-dimensional network structure with 24-atom rings which are composed of Tb, C and O atoms. The complex displays green fluorescence emission in the solid state at room temperature, which corresponds to 5D4 → 7F5 transition of the Tb(III) ion.
文摘The title compound (Z)-1-(3-fluorobenzyl)-5-((3-fluorobenzylimino)(2-hydroxy-4- methoxyphenyl)methyl)pyridin-2(1H)-one (C27H22F2N2O3,Mr = 460.47) was synthesized and crystallized. The crystal belongs to the triclinic system,space group P1 with a = 9.951(6),b = 10.059(6),c = 12.927(7)A,α = 109.828(7),β = 102.304(7),γ = 104.898(7)°,Z = 2,V = 1110.2(11)A^3,Dc =1.377 Mg/m^3,μ(MoKα) = 0.102 mm^-1,F(000) = 480,the final R = 0.0449 and Rw = 0.1250 for 4595 observed reflections (I 〉 2σ(I)). X-ray analysis reveals that both m-fluorobenzyl groups are diorientationally disordered because of the rotation of C–C single bond which was represented as F(1),F(2) and F(1'),F(2'). The diorientational disorder was refined and gave the occupancies of 0.665(4) and 0.335(4) for F(1) and F(1'),0.631(3) and 0.369(3) for F(2) and F(2'). Hydrogen bonds existing in the cell link different components to stabilize the crystal structure. The active data proved that the title compound has good anti-HBV activity.
基金financially supported by the 973 Program(No.2015CB654700 or 2015654702)the National Natural Science Foundation of China(Nos.51473156 and 51203147)
文摘Cobalt and nickel complexes (la-ld and 2a-2d, respectively) supported by 2-imidate-pyridine ligands were synthesized and used for 1,3-butadiene polymerization. The complexes were characterized by IR and element analysis, and complex la was further characterized by single-crystal X-ray diffraction. The solid state structure of complex la displayed a distorted tetrahedral geometry. Upon activation with ethylaluminum sesquichloride (EASC), all the complexes showed high activities toward 1,3-butadiene polymerization. The cobalt complexes produced polymers with high cis-1,4 contents and high molecular weights, while the nickel complexes displayed low cis-l,4 selectivity and the resulting polymers had low molecular weights. The catalytic activities of the complexes highly depended on the ligand structure. With the increment of polymerization temperature, the cis-1,4 content and the molecular weight of the resulting polymer decreased.
基金Supported by the Natural Science Foundation of Fujian Province (B0510012) and the Science and Technology of Science Foundation of Fujian Education Department (JA04189)
文摘The copper(Ⅱ) complexes of pyridine-3-carboxylic acid (nicotinic acid) and pyridine-2-carboxylic acid (isonicotinic acid) were synthesized, and their structures were characterized by elemental analysis, infrared spectrum, powder X-ray diffraction and so on. The results show that under experimental conditions, the ligands of synthesized copper nicotinate and copper isonicotinate are coordinated simultaneity with copper(Ⅱ) via the nitrogen of pyridine group and an oxygen of carboxylic acid group to form bidentate chelates. The crystal of copper nicotinate with two six-membered chelate rings belongs to monoclinic system, while that of copper isonicotinate having two five-membered chelate rings is of triclinic system. The tests show that the biological activities, such as the improvement of feed utilization, growth, anti-oxidation ability of organism and disease-resistant power, are different when copper nicotinate, copper inicotinate, copper-lysine chelate, copper-methionine chelate and copper sulphate are added in pig's feed, respectively. Due to its higher biological activity, less pollution and lower toxicity, copper nicotinate has wide potential applications as a feed additive.
文摘2-(pyridine-2-yl)-N-p-chlorohydrazinecarbothioamide (HCPTS) was synthesized, characterized and successfully applied for the preconcentration of Cu(II), Ni(II), Zn(II), Cd(II), Co(II), Pb(II), Fe(II), and Hg(II) in water, blood, and urine samples prior to graphite furnace atomic absorption determination (GFAAS);Hg was determined by cold vapor technique. Under the optimum experimental conditions (i.e. pH = 8, 10–4 M of HCPTS, 0.05% w/v of Triton X-114), calibration graphs were linear in the range of 0.02 to 200 ng?mL–1 for Co(II), Cd(II), Pb(II) and Ni(II);0.03 to 200 ng?mL–1 for Cu(II);0.07 to 200 ng?mL–1 for Fe(II) and Zn(II) and 0.02 to 150 ng?mL–1 for Hg(II). The enrichment factors were 43, 51, 41, 46, 54, 40, 45 and 52 for Cu(II), Ni(II),Zn (II), Cd(II), Co(II), Pb(II), Fe(II), and Hg(II), respectively. The limit of detection were found to be 0.019, 0.094, 0.0514, 0.052, 0.0165, 0.047, 0.068 and 0.041 ng?mL–1 for Cu(II), Ni(II), Zn(II), Cd(II), Co(II), Pb(II), Fe(II), and Hg(II), respectively. The developed method was applied to the determination of these metal ions in water, blood and urine samples with satisfactory results.
基金the National Natural Science Foundation of China (Grant Nos. 20332030, 20572027, 20625205 and 20772034)Guangdong Natural Science Foundation (Grant No. 07118070)
文摘A novel and green method for the synthesis of dimethyl pyridine-3,5-dicarboxylate has been developed. It is PdCl2-catalyzed heterocyclotrimerization of methyl acrylate with urea in methanol/supercritical carbon dioxide. The target compound was obtained with a 75% isolated yield under the optimized con-ditions.
基金financially supported by the Youth Teachers’Training Foundation of Minnan Science and Technology Institute,Young and Middle-age Academic Leader Plan of Quanzhou University,National University Student Innovation and Entrepreneurship Project(201812992001)the undergraduate education teaching reform in Fujian province(2017)
文摘A new luminescent compound, {[Eu3(L)4(H2 O)8]·(NO3)·4 H2 O}n(1, H2 L = 2-(pyridine-3-yl)-imidazole-4,5-dicarboxylic acid) has been solvothermally synthesized and structurally characterized by elemental analyses, IR and single-crystal X-ray diffraction. 1 crystallizes in monoclinic, space group C2/c with a = 21.0183(19), b = 9.5227(6), c = 28.227(3) ?, β = 106.885(5)o, V = 5406.1(8) ?3, Dc = 2.038 g/cm3, μ = 3.358 mm-1, Mr = 1658.76, F(000) = 3247, Z = 4, the final R = 0.0488, wR = 0.1195 and S = 1.075. The deprotonated L ligand employs a μ4-bridge to coordinate with three Eu(Ⅲ) ion, forming a wave-like(3,4)-connected 2 D structure. The existence of π···π interaction between the pyridine rings of L ligands leads to an infinite 3 D network. Furthermore, the thermal analysis, powder diffraction and solid-state photoluminescent properties of compound 1 have also been investigated.