Microwave assisted efficient Hantzsch reaction via four-component coupling reactions of tetrazolo[1,5-α]quinoline-4-carbal-dehyde, dimedone/cyclohexane-1,3-dione,ethyl/methyl acetoacetate and ammonium acetate was des...Microwave assisted efficient Hantzsch reaction via four-component coupling reactions of tetrazolo[1,5-α]quinoline-4-carbal-dehyde, dimedone/cyclohexane-1,3-dione,ethyl/methyl acetoacetate and ammonium acetate was described as the preparation of tetrazolo[1,5-α]quinoline based 1,4-dihydropyridines,acridine-1,8-diones and polyhydroquinolines.The process presented here is simple,rapid,environmentally welcoming and high yielding.All the derivatives were subjected to an in vitro antimicrobial screening against a representative panel of bacteria and fungi and results worth further investigations.展开更多
The corrosion behavior of aluminum alloy 2024-T3 was studied in 3.5% NaCl solution with two fluorescence quinoline compounds named 8-hydroxy-quinoline(8HQ) and 8-hydroxy-quinoline-5-sulfonic acid(HQS). The open circui...The corrosion behavior of aluminum alloy 2024-T3 was studied in 3.5% NaCl solution with two fluorescence quinoline compounds named 8-hydroxy-quinoline(8HQ) and 8-hydroxy-quinoline-5-sulfonic acid(HQS). The open circuit potential(OCP) test result indicates that both compounds change the alloy corrosion potential by adsorbing on the electrode surface. Polarization measurements show that 8HQ is a mixed type inhibitor by blocking the active sites of the metal surface, while HQS is a corrosion accelerator by activating the cathodic reaction. Changes of the impedance parameters in the electrochemical impedance spectroscopy(EIS) are related to the adsorption of 8HQ on the metal surface, which leads to the formation of a protective layer. The impedance diagram in the solution with HQS is similar to the one without additional organic compounds. The morphology and composition of the protective layer were studied by using SEM/EDS. The result confirms the function of the additions that the effect of 8HQ is due to the insoluble aluminum chelate, Al(HQ)3, to prevent adsorption of chloride ion, while the effect of HQS is to break down the oxide film.展开更多
Electronic structures and absorption spectra properties of complex 8-（（trimethoxysilyl）methylthio）quinoline.SnCh in gas phase and MeCN media have been investigated by using DFT/TD-DFT method. The calculated lowest...Electronic structures and absorption spectra properties of complex 8-（（trimethoxysilyl）methylthio）quinoline.SnCh in gas phase and MeCN media have been investigated by using DFT/TD-DFT method. The calculated lowest-energy absorption band shows different mechanisms under these two conditions, and it bears LMCT/LLCT/ILCT character in MeCN solution and LLCT/ILCT character in gas phase. The calculated absorption bands of the title complex in MeCN solvent are in good agreement with the experimental results, and calculation results indicate that the very weak experimentally observed lowest-energy absorption band of the title complex in MeCN solvent originates from the spin-forbidden singlet-triplet transitions.展开更多
Herein,we report the first Rh~Ⅲ-catalyzed regioselective C8 arylation of quinoline N-oxides with commercially available arylboronic acids as coupling partners.This procedure is simple,and the reaction shows perfect r...Herein,we report the first Rh~Ⅲ-catalyzed regioselective C8 arylation of quinoline N-oxides with commercially available arylboronic acids as coupling partners.This procedure is simple,and the reaction shows perfect regioselectivity,a broad substrate scope,and isolated yields of up to 92%.We demonstrate the utility of the reaction by using it for late-stage functionalization of a fungicide.展开更多
A series of half-titanocene chloride 2-（benzimidazol-2-yl）quinolin-8-olates C1-C6 were synthesized by treating the lithium salts of the ligand with CpTiCI3. All the complexes were characterized by 1H-NMR, 13C-NMR an...A series of half-titanocene chloride 2-（benzimidazol-2-yl）quinolin-8-olates C1-C6 were synthesized by treating the lithium salts of the ligand with CpTiCI3. All the complexes were characterized by 1H-NMR, 13C-NMR and elemental analyses, and the crystal structure of C3 and C6 was measured by X-ray. These half-titanocene complexes showed moderate catalytic activities toward ethylene polymerization （up to 1840 kg·mol-1（Ti）·h-1） when activated with MMAO, affording the high molecular weight polymers. And they also exhibited good activity for copolymerization of ethylene and a-olefin with low content of co-monomer.展开更多
A novel two-dimensional lead（II） coordination polymer 1, [C11H7Cl2NO3Pb]n, has been prepared by solvothermal reaction of new bridging ligand（5-chloro-quinolin-8-yloxy）acetic acid（HL） with PbCl2, and its structur...A novel two-dimensional lead（II） coordination polymer 1, [C11H7Cl2NO3Pb]n, has been prepared by solvothermal reaction of new bridging ligand（5-chloro-quinolin-8-yloxy）acetic acid（HL） with PbCl2, and its structure was characterized by IR, elemental analysis, TG-DTA and single-crystal X-ray diffraction analysis. The crystal is of monoclinic system, space group P21/c with a = 16.7603（7）, b = 8.6907（4）, c = 8.4745（3）A, β = 101.1110（11）°, C11H7Cl2NO3 Pb, Mr = 479.27, V = 1211.25（9）A3, Z = 4, Dc = 2.628 g/cm^3, F（000） = 880, μ = 14.367 mm^-1, R = 0.0173 and wR = 0.0508. The asymmetric unit contains one lead（II） cation, one（5-chloro-quinolin-8-yloxy）acetate（L） ligand and a chloride ion. The PbII center is hepta-coordinated in a distorted pentagonal bipyramidal geometry. The coordination sphere of the Pb atom is completed by two oxygen atoms and one nitrogen atom of the same L ligand, two bridging chloride ions and two bridging oxygen atoms of two adjacent L ligands. Two PbII centers are linked by the two L ligands to form a C2-symmetric dimer unit with a planar [Pb2O2] ring. Each dimer unit acts as a secondary building unit（SBU） and links adjacent four dimer units by the chloride atoms and oxygen atoms of carboxylate groups of L, forming a two-dimensional array. Such two-dimensional layers are packed through intermolecular C–H…Cl hydrogen bonds into a three-dimensional supramolecular structure. When the dimer unit is viewed as a 4-connected node, 1 is simplified as a 4-nodal 2-D network with square lattices of the diagonal lengths to be 6.079（1）A. The fluorescence emission peak of complex 1 appears near 407 nm.展开更多
A series of nickel halides bearing 2,4-di-t-butyl-6-（quinolin-8-yliminomethyl） phenolate ligands was synthesized and characterized by IR spectroscopy and elemental analysis. Molecular structures of C1 （R = H, X = B...A series of nickel halides bearing 2,4-di-t-butyl-6-（quinolin-8-yliminomethyl） phenolate ligands was synthesized and characterized by IR spectroscopy and elemental analysis. Molecular structures of C1 （R = H, X = Br） and C2 （R = H, X = C1） were further confirmed by single-crystal X-ray crystallographic studies, and revealed a distorted square planar geometry at nickel. Upon activation with diethylaluminum chloride （Et2AlCl）, all nickel pre-catalysts displayed good catalytic activity [up to 9.3 × 10^5 g mol-1（Ni） h-1] for ethylene oligomerization with major dimerization. In the presence of methylaluminoxane （MAO）, the nickel complex C1 was capable of ethylene polymerization under 3 MPa, and produced polyethylene products with narrow polydispersity （1.16-1.73） and molecular weights in the range of 2.6-4.95 kg/mol.展开更多
This paper described a novel method for the preconcentration of Pb（II） using microcrystalline triphenylmethane loaded with quinolin-8-olate prior to the determination by flame atomic absorption spectrometry. Pb（II...This paper described a novel method for the preconcentration of Pb（II） using microcrystalline triphenylmethane loaded with quinolin-8-olate prior to the determination by flame atomic absorption spectrometry. Pb（II） could be enriched by controlling appropriate condition. The preconcentration factor could reach to 200 and the detection limit of Pb（II） was 0.074 μg/L. The recovery was in a range of 93.5-103% with relative standard deviation of 1.0-2.2%. The proposed method had been successfully applied to the determination of trace Pb（U） in various water samples with satisfactory result.展开更多
The reaction of Os(RL1)(PPh3)2(CO)Br, 1b, with qui-nolin-8-ol (HQ), 2, has furnished complexes of the type [Os(RL2)(PPh3)2(CO)(Q)], 3, in excellent yield (RL1 is C6H2O-2-CHNHC6H4R(p)-3-Me-5, RL2 is C6H2OH-2-CHNC6H4R(p...The reaction of Os(RL1)(PPh3)2(CO)Br, 1b, with qui-nolin-8-ol (HQ), 2, has furnished complexes of the type [Os(RL2)(PPh3)2(CO)(Q)], 3, in excellent yield (RL1 is C6H2O-2-CHNHC6H4R(p)-3-Me-5, RL2 is C6H2OH-2-CHNC6H4R(p)-3-Me-5 and R is Me, OMe, Cl). In this process, quinolin-8-olato (Q) undergoes five-membered chelation, the iminium-phenolato function tautomerizing to the imine-phenol function. The trans geometry of the Os(PPh3)2 fragment is consistent with the occurrence of a single 31P resonance near –6.0 ppm in 3. In dichloromethane solution, 3 displays a quasireversible 3+/3 couple near 0.40 V vs. SCE (3+ is the osmium (III) analogue of 3). Coulometrically generated solutions of 3+ displays a strong absorption near 340 nm, 415 nm and 500 nm and are one-electron paramagnetic (low-spin d5, S = 1/2) and show rhombic EPR spectra in 1:1 dichloromethanetoluene solution at 77 K with g values near 2.44, 2.20, 1.83. Distortion parameters using the observed g values have been computed. Solutions of 3 absorb near 420 nm and emit near 510 nm at 298 K and 580 nm at 77 K. The fluorescence is believed to originate from the 3MLCT state.展开更多
The title compound was synthesized by the base catalyzed reaction of 5-（（quinolin- 8-yloxy）methyl）-1,3,4-oxadiazole-2（3H）-thione with methyl chloroacetate. The structure was supported by the spectroscopic data a...The title compound was synthesized by the base catalyzed reaction of 5-（（quinolin- 8-yloxy）methyl）-1,3,4-oxadiazole-2（3H）-thione with methyl chloroacetate. The structure was supported by the spectroscopic data and unambiguously confirmed by single-crystal X-ray diffraction studies. It crystallizes from a methanol solution in the triclinic space group Pi with unit cell dimensions a = 7.4509（9）, b = 10.2389（12）, c = 12.2299（15）A, a = 74.771（2）, β = 77.956（2）, 7 = 69.263（2）°, V = 834.98（17） A3 and Z = 2. In order to gain some valuable insights into the molecular structure, the quantum mechanical calculations were performed using both HF and time-dependent density functional theory at the B3LYP/6-31G（d,p） level. The molecular geometry from X-ray determination of the title compound in the ground state has been compared using the Hartree-Fock （HF） and density functional theory （DFT） with the 6-31G（d） basis set. The calculated results show that the DFT and HF can well reproduce the structure of the title compound. The energetic behavior of the title compound was examined using the B3LYP method with the 6-31G（d） basis set. The harmonic vibrational frequencies calculated have been compared with the experimental FTIR and FT-Raman spectra. The restricted Hartree-Fock and density functional theory-based nuclear magnetic resonance （NMR） calculation procedure was also performed, and it was used for assigning the 13C and 1H NMR chemical shifts of the title compound. Moreover, molecular electrostatic potential and thermodynamic parameters of the title compound were investigated by theoretical calculations.展开更多
An efficient greener one pot synthesis of dimethyl-dihydro-7H-chromeno[3, 2-h]quinolin-8(9H)-one derivatives has been synthesized through cyclization of aromatic aldehyde, dimidone and 8-hydroxy-quinoline through one-...An efficient greener one pot synthesis of dimethyl-dihydro-7H-chromeno[3, 2-h]quinolin-8(9H)-one derivatives has been synthesized through cyclization of aromatic aldehyde, dimidone and 8-hydroxy-quinoline through one-pot condensation method is described. The synthesized compounds are screened for further biological activities against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus subtilis, Bacillus using cut plate method and disc diffusion method.展开更多
We have prepared the (5-chloro-quinolin-8-yloxy) acetic acid and characterized it by using infrared, Raman and multi-dimensional nuclear magnetic resonance spectroscopies. The density functional theory (DFT) together ...We have prepared the (5-chloro-quinolin-8-yloxy) acetic acid and characterized it by using infrared, Raman and multi-dimensional nuclear magnetic resonance spectroscopies. The density functional theory (DFT) together with the 6-31G* and 6-311++G** basis sets were used to study its structure and vibrational properties. Three stable conformations of the compound were theoretically determined in gas phase and probably these conformations are present in the solid phase. The harmonic vibrational wavenumbers for the optimized geometries were calculated at the same theory levels. For a complete assignment of the observed bands in the vibrational spectra, the DFT calculations were combined with Pulay’s scaled quantum mechanical force field (SQMFF) methodology in order to fit the theoretical wavenumber values to the experimental ones. Besides, the force constants of the three conformers of (5-chloro-quinolin-8-yloxy) acetic acid were calculated and compared with those obtained by us for the 2-(quinolin-8-yloxy) acetic acid. In addition, the characteristics of the electronic delocalization of those structures were performed by using natural bond orbital (NBO), while the corresponding topological properties of electronic charge density are analysed by employing Bader’s atoms in molecules theory (AIM).展开更多
Two novel mononuclear complexes with 5-chloro-8-（methoxycarbonylmethoxy）quinoline ligand（L）, namely, HgLBr2 1 and CuL2Cl2 2, have been prepared by solvothermal reaction of（5-chloro-quinolin-8-yloxy）acetic acid w...Two novel mononuclear complexes with 5-chloro-8-（methoxycarbonylmethoxy）quinoline ligand（L）, namely, HgLBr2 1 and CuL2Cl2 2, have been prepared by solvothermal reaction of（5-chloro-quinolin-8-yloxy）acetic acid with HgBr2 and CuCl2, respectively. Their structures were characterized by IR, elemental analysis, UV-Vis-NIR spectra, TG and single-crystal X-ray diffraction analysis. Interestingly,（5-chloro-quinolin-8-yloxy）acetic acid is changed as 5-chloro-8-（methoxycarbonylmethoxy）quinoline ligand（L） in complexes 1 and 2. Crystal data for 1： C12H10Br2 Cl Hg NO3, Mr = 612.07, triclinic, space group P1 with a = 8.5983（7）, b = 9.7726（6）, c = 10.1549（6） A, α = 66.355（6）, β = 77.067（8）, γ = 78.803（8）°, V = 756.6（9）A^3, Z = 2, Dc = 2.687 g/cm^3, F（000） = 560, μ = 15.633 mm^-1, R = 0.0351 and w R = 0.0504. Crystal data for 2： C24H20Cl4 Cu N2O6, Mr = 637.76, triclinic, space group P1 with a = 10.5324（9）, b = 11.2377（16）, c = 12.0143（12） ？, α = 83.413（11）, β = 64.475（9）, γ = 83.144（11）°, V = 1270.9（2） ？3, Z = 2, Dc = 1.667 g/cm3, F（000） = 646, μ = 1.324 mm-1, R = 0.0408 and wR = 0.0922. In 1, the HgII centre is a distorted trigonal planar geometry comprised of two Br atoms and one quinoline N atom of L. Intermolecular π-π, C–H…π stacking interactions and intermolecular C–H…Br hydrogen bonds are observed in the molecular packing of 1. In complex 2, each CuII center has a distorted octahedral geometry comprised of two chloride ions, two quinoline N atoms and two O atoms of two L ligands. Intermolecular C–H…Cl hydrogen bonds exist in the molecular packing of 2. The fluorescence emission peak of complexes 1 and 2 appears near 406 and 410 nm, respectively. Optical diffuse-reflection spectral results suggest complex 1 has the property of semiconductor.展开更多
Synthesis of half metallocene complexes ([O,N]CpTiCl 2) containing 8 hydroxy quinoline ligand is described.The results indicate that [O,N]CpTiCl 2 is active for ethylene polymerization at 30℃ and 0.1?mPa with MAO act...Synthesis of half metallocene complexes ([O,N]CpTiCl 2) containing 8 hydroxy quinoline ligand is described.The results indicate that [O,N]CpTiCl 2 is active for ethylene polymerization at 30℃ and 0.1?mPa with MAO activation,and exhibits much higher activity than CpTiCl\-3.The results show that when there is an electron donor substituent next to N,such as a methyl,the activity of [O,N]CpTiCl 2 increases greatly; however,if there is an electron acceptor substituent,such as nitro in the benzene ring,it is inactive.For the [O,N]CpTiCl 2/MAO system,the polymerization rate is “up and down” type with increasing the Al/Ti molar ratio.The activity reaches its maximum at molar ratio of Al/Ti = 500,which is over 1×10 5?gPE/molTi·h.The activity decreases as the polymerization time is longer.The polyethylene obtained is characteristic of narrow molecular distribution with molecular weight M w around 40×10 4 and molecular weight ratio M w/ M n=2 8.展开更多
文摘Microwave assisted efficient Hantzsch reaction via four-component coupling reactions of tetrazolo[1,5-α]quinoline-4-carbal-dehyde, dimedone/cyclohexane-1,3-dione,ethyl/methyl acetoacetate and ammonium acetate was described as the preparation of tetrazolo[1,5-α]quinoline based 1,4-dihydropyridines,acridine-1,8-diones and polyhydroquinolines.The process presented here is simple,rapid,environmentally welcoming and high yielding.All the derivatives were subjected to an in vitro antimicrobial screening against a representative panel of bacteria and fungi and results worth further investigations.
基金Project(50571003) supported by the National Natural Science Foundation of China
文摘The corrosion behavior of aluminum alloy 2024-T3 was studied in 3.5% NaCl solution with two fluorescence quinoline compounds named 8-hydroxy-quinoline(8HQ) and 8-hydroxy-quinoline-5-sulfonic acid(HQS). The open circuit potential(OCP) test result indicates that both compounds change the alloy corrosion potential by adsorbing on the electrode surface. Polarization measurements show that 8HQ is a mixed type inhibitor by blocking the active sites of the metal surface, while HQS is a corrosion accelerator by activating the cathodic reaction. Changes of the impedance parameters in the electrochemical impedance spectroscopy(EIS) are related to the adsorption of 8HQ on the metal surface, which leads to the formation of a protective layer. The impedance diagram in the solution with HQS is similar to the one without additional organic compounds. The morphology and composition of the protective layer were studied by using SEM/EDS. The result confirms the function of the additions that the effect of 8HQ is due to the insoluble aluminum chelate, Al(HQ)3, to prevent adsorption of chloride ion, while the effect of HQS is to break down the oxide film.
基金Supported by the National Natural Science Foundation of China (Nos. 20473055 and 20773089)the Scientific Research Foundation for the Returned Overseas Chinese Scholars, State Education Ministry (No. 20071108-18-15)
文摘Electronic structures and absorption spectra properties of complex 8-（（trimethoxysilyl）methylthio）quinoline.SnCh in gas phase and MeCN media have been investigated by using DFT/TD-DFT method. The calculated lowest-energy absorption band shows different mechanisms under these two conditions, and it bears LMCT/LLCT/ILCT character in MeCN solution and LLCT/ILCT character in gas phase. The calculated absorption bands of the title complex in MeCN solvent are in good agreement with the experimental results, and calculation results indicate that the very weak experimentally observed lowest-energy absorption band of the title complex in MeCN solvent originates from the spin-forbidden singlet-triplet transitions.
基金the National Natural Science Foundation of China(Nos.21977056,21732002,21672117,21602117,21772104,31760527)the Tianjin Natural Science Foundation(No.16JCZDJC32400)for generous financial support for our programs。
文摘Herein,we report the first Rh~Ⅲ-catalyzed regioselective C8 arylation of quinoline N-oxides with commercially available arylboronic acids as coupling partners.This procedure is simple,and the reaction shows perfect regioselectivity,a broad substrate scope,and isolated yields of up to 92%.We demonstrate the utility of the reaction by using it for late-stage functionalization of a fungicide.
基金supported by NSFC (No. 20904059)Key Project of 863 Program of China(No. 2009AA034605)
文摘A series of half-titanocene chloride 2-（benzimidazol-2-yl）quinolin-8-olates C1-C6 were synthesized by treating the lithium salts of the ligand with CpTiCI3. All the complexes were characterized by 1H-NMR, 13C-NMR and elemental analyses, and the crystal structure of C3 and C6 was measured by X-ray. These half-titanocene complexes showed moderate catalytic activities toward ethylene polymerization （up to 1840 kg·mol-1（Ti）·h-1） when activated with MMAO, affording the high molecular weight polymers. And they also exhibited good activity for copolymerization of ethylene and a-olefin with low content of co-monomer.
基金Supported by Key Laboratory of Organic Synthesis of Jiangsu Province(KJS1308)
文摘A novel two-dimensional lead（II） coordination polymer 1, [C11H7Cl2NO3Pb]n, has been prepared by solvothermal reaction of new bridging ligand（5-chloro-quinolin-8-yloxy）acetic acid（HL） with PbCl2, and its structure was characterized by IR, elemental analysis, TG-DTA and single-crystal X-ray diffraction analysis. The crystal is of monoclinic system, space group P21/c with a = 16.7603（7）, b = 8.6907（4）, c = 8.4745（3）A, β = 101.1110（11）°, C11H7Cl2NO3 Pb, Mr = 479.27, V = 1211.25（9）A3, Z = 4, Dc = 2.628 g/cm^3, F（000） = 880, μ = 14.367 mm^-1, R = 0.0173 and wR = 0.0508. The asymmetric unit contains one lead（II） cation, one（5-chloro-quinolin-8-yloxy）acetate（L） ligand and a chloride ion. The PbII center is hepta-coordinated in a distorted pentagonal bipyramidal geometry. The coordination sphere of the Pb atom is completed by two oxygen atoms and one nitrogen atom of the same L ligand, two bridging chloride ions and two bridging oxygen atoms of two adjacent L ligands. Two PbII centers are linked by the two L ligands to form a C2-symmetric dimer unit with a planar [Pb2O2] ring. Each dimer unit acts as a secondary building unit（SBU） and links adjacent four dimer units by the chloride atoms and oxygen atoms of carboxylate groups of L, forming a two-dimensional array. Such two-dimensional layers are packed through intermolecular C–H…Cl hydrogen bonds into a three-dimensional supramolecular structure. When the dimer unit is viewed as a 4-connected node, 1 is simplified as a 4-nodal 2-D network with square lattices of the diagonal lengths to be 6.079（1）A. The fluorescence emission peak of complex 1 appears near 407 nm.
文摘A series of nickel halides bearing 2,4-di-t-butyl-6-（quinolin-8-yliminomethyl） phenolate ligands was synthesized and characterized by IR spectroscopy and elemental analysis. Molecular structures of C1 （R = H, X = Br） and C2 （R = H, X = C1） were further confirmed by single-crystal X-ray crystallographic studies, and revealed a distorted square planar geometry at nickel. Upon activation with diethylaluminum chloride （Et2AlCl）, all nickel pre-catalysts displayed good catalytic activity [up to 9.3 × 10^5 g mol-1（Ni） h-1] for ethylene oligomerization with major dimerization. In the presence of methylaluminoxane （MAO）, the nickel complex C1 was capable of ethylene polymerization under 3 MPa, and produced polyethylene products with narrow polydispersity （1.16-1.73） and molecular weights in the range of 2.6-4.95 kg/mol.
文摘This paper described a novel method for the preconcentration of Pb（II） using microcrystalline triphenylmethane loaded with quinolin-8-olate prior to the determination by flame atomic absorption spectrometry. Pb（II） could be enriched by controlling appropriate condition. The preconcentration factor could reach to 200 and the detection limit of Pb（II） was 0.074 μg/L. The recovery was in a range of 93.5-103% with relative standard deviation of 1.0-2.2%. The proposed method had been successfully applied to the determination of trace Pb（U） in various water samples with satisfactory result.
文摘The reaction of Os(RL1)(PPh3)2(CO)Br, 1b, with qui-nolin-8-ol (HQ), 2, has furnished complexes of the type [Os(RL2)(PPh3)2(CO)(Q)], 3, in excellent yield (RL1 is C6H2O-2-CHNHC6H4R(p)-3-Me-5, RL2 is C6H2OH-2-CHNC6H4R(p)-3-Me-5 and R is Me, OMe, Cl). In this process, quinolin-8-olato (Q) undergoes five-membered chelation, the iminium-phenolato function tautomerizing to the imine-phenol function. The trans geometry of the Os(PPh3)2 fragment is consistent with the occurrence of a single 31P resonance near –6.0 ppm in 3. In dichloromethane solution, 3 displays a quasireversible 3+/3 couple near 0.40 V vs. SCE (3+ is the osmium (III) analogue of 3). Coulometrically generated solutions of 3+ displays a strong absorption near 340 nm, 415 nm and 500 nm and are one-electron paramagnetic (low-spin d5, S = 1/2) and show rhombic EPR spectra in 1:1 dichloromethanetoluene solution at 77 K with g values near 2.44, 2.20, 1.83. Distortion parameters using the observed g values have been computed. Solutions of 3 absorb near 420 nm and emit near 510 nm at 298 K and 580 nm at 77 K. The fluorescence is believed to originate from the 3MLCT state.
文摘The title compound was synthesized by the base catalyzed reaction of 5-（（quinolin- 8-yloxy）methyl）-1,3,4-oxadiazole-2（3H）-thione with methyl chloroacetate. The structure was supported by the spectroscopic data and unambiguously confirmed by single-crystal X-ray diffraction studies. It crystallizes from a methanol solution in the triclinic space group Pi with unit cell dimensions a = 7.4509（9）, b = 10.2389（12）, c = 12.2299（15）A, a = 74.771（2）, β = 77.956（2）, 7 = 69.263（2）°, V = 834.98（17） A3 and Z = 2. In order to gain some valuable insights into the molecular structure, the quantum mechanical calculations were performed using both HF and time-dependent density functional theory at the B3LYP/6-31G（d,p） level. The molecular geometry from X-ray determination of the title compound in the ground state has been compared using the Hartree-Fock （HF） and density functional theory （DFT） with the 6-31G（d） basis set. The calculated results show that the DFT and HF can well reproduce the structure of the title compound. The energetic behavior of the title compound was examined using the B3LYP method with the 6-31G（d） basis set. The harmonic vibrational frequencies calculated have been compared with the experimental FTIR and FT-Raman spectra. The restricted Hartree-Fock and density functional theory-based nuclear magnetic resonance （NMR） calculation procedure was also performed, and it was used for assigning the 13C and 1H NMR chemical shifts of the title compound. Moreover, molecular electrostatic potential and thermodynamic parameters of the title compound were investigated by theoretical calculations.
文摘An efficient greener one pot synthesis of dimethyl-dihydro-7H-chromeno[3, 2-h]quinolin-8(9H)-one derivatives has been synthesized through cyclization of aromatic aldehyde, dimidone and 8-hydroxy-quinoline through one-pot condensation method is described. The synthesized compounds are screened for further biological activities against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus subtilis, Bacillus using cut plate method and disc diffusion method.
文摘We have prepared the (5-chloro-quinolin-8-yloxy) acetic acid and characterized it by using infrared, Raman and multi-dimensional nuclear magnetic resonance spectroscopies. The density functional theory (DFT) together with the 6-31G* and 6-311++G** basis sets were used to study its structure and vibrational properties. Three stable conformations of the compound were theoretically determined in gas phase and probably these conformations are present in the solid phase. The harmonic vibrational wavenumbers for the optimized geometries were calculated at the same theory levels. For a complete assignment of the observed bands in the vibrational spectra, the DFT calculations were combined with Pulay’s scaled quantum mechanical force field (SQMFF) methodology in order to fit the theoretical wavenumber values to the experimental ones. Besides, the force constants of the three conformers of (5-chloro-quinolin-8-yloxy) acetic acid were calculated and compared with those obtained by us for the 2-(quinolin-8-yloxy) acetic acid. In addition, the characteristics of the electronic delocalization of those structures were performed by using natural bond orbital (NBO), while the corresponding topological properties of electronic charge density are analysed by employing Bader’s atoms in molecules theory (AIM).
基金Supported by Key Laboratory of Organic Synthesis of Jiangsu Province(KJS1308)
文摘Two novel mononuclear complexes with 5-chloro-8-（methoxycarbonylmethoxy）quinoline ligand（L）, namely, HgLBr2 1 and CuL2Cl2 2, have been prepared by solvothermal reaction of（5-chloro-quinolin-8-yloxy）acetic acid with HgBr2 and CuCl2, respectively. Their structures were characterized by IR, elemental analysis, UV-Vis-NIR spectra, TG and single-crystal X-ray diffraction analysis. Interestingly,（5-chloro-quinolin-8-yloxy）acetic acid is changed as 5-chloro-8-（methoxycarbonylmethoxy）quinoline ligand（L） in complexes 1 and 2. Crystal data for 1： C12H10Br2 Cl Hg NO3, Mr = 612.07, triclinic, space group P1 with a = 8.5983（7）, b = 9.7726（6）, c = 10.1549（6） A, α = 66.355（6）, β = 77.067（8）, γ = 78.803（8）°, V = 756.6（9）A^3, Z = 2, Dc = 2.687 g/cm^3, F（000） = 560, μ = 15.633 mm^-1, R = 0.0351 and w R = 0.0504. Crystal data for 2： C24H20Cl4 Cu N2O6, Mr = 637.76, triclinic, space group P1 with a = 10.5324（9）, b = 11.2377（16）, c = 12.0143（12） ？, α = 83.413（11）, β = 64.475（9）, γ = 83.144（11）°, V = 1270.9（2） ？3, Z = 2, Dc = 1.667 g/cm3, F（000） = 646, μ = 1.324 mm-1, R = 0.0408 and wR = 0.0922. In 1, the HgII centre is a distorted trigonal planar geometry comprised of two Br atoms and one quinoline N atom of L. Intermolecular π-π, C–H…π stacking interactions and intermolecular C–H…Br hydrogen bonds are observed in the molecular packing of 1. In complex 2, each CuII center has a distorted octahedral geometry comprised of two chloride ions, two quinoline N atoms and two O atoms of two L ligands. Intermolecular C–H…Cl hydrogen bonds exist in the molecular packing of 2. The fluorescence emission peak of complexes 1 and 2 appears near 406 and 410 nm, respectively. Optical diffuse-reflection spectral results suggest complex 1 has the property of semiconductor.
文摘Synthesis of half metallocene complexes ([O,N]CpTiCl 2) containing 8 hydroxy quinoline ligand is described.The results indicate that [O,N]CpTiCl 2 is active for ethylene polymerization at 30℃ and 0.1?mPa with MAO activation,and exhibits much higher activity than CpTiCl\-3.The results show that when there is an electron donor substituent next to N,such as a methyl,the activity of [O,N]CpTiCl 2 increases greatly; however,if there is an electron acceptor substituent,such as nitro in the benzene ring,it is inactive.For the [O,N]CpTiCl 2/MAO system,the polymerization rate is “up and down” type with increasing the Al/Ti molar ratio.The activity reaches its maximum at molar ratio of Al/Ti = 500,which is over 1×10 5?gPE/molTi·h.The activity decreases as the polymerization time is longer.The polyethylene obtained is characteristic of narrow molecular distribution with molecular weight M w around 40×10 4 and molecular weight ratio M w/ M n=2 8.
