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2014 Volume 33 Issue 6
2014, 33(6): 813-820
Abstract:
The molecular geometries, frontier molecular orbital properties, and absorption and emission properties of three 4-phenoxy-1,8-naphthalimide derivatives, namely 4-phenoxy-N-(2-hydroxyethyl)-1,8-naphthalimide(1),4-(2-tert-butylphenoxy)-N-(2-hydroxyethyl)-1,8-naphthalimide (2), and 4-[2,4-di(tert-butyl)]phenoxy-N-(2-hydroxyethyl)-1,8-naphthalimide (3), are investigated by density functional theory (DFT) and time-dependent density functional theory (TD-DFT) calculations in conjunction with polarizable continuum models (PCMs). Four functionals and ten basis sets are employed for 1 to calculate the electron transition energies, which were compared with the experimental observations. Our results reveal that the B3LYP/6-311+G(d,p) method is the best choice to reproduce the experimental spectra. Moreover, the effects of substituents on the molecular geometries, electronic structures, absorption and emission spectra are also studied at the B3LYP/6-311+G(d,p) level. We find that the gap between the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) decreases with increasing the number of tert-butyl substituents onto the phenoxy groups, suggesting red-shift of the absorption and emission bands. This is related to the increase of conjugation from 1 to 2 and 3. Our calculations are in good agreement with the experimental results.
The molecular geometries, frontier molecular orbital properties, and absorption and emission properties of three 4-phenoxy-1,8-naphthalimide derivatives, namely 4-phenoxy-N-(2-hydroxyethyl)-1,8-naphthalimide(1),4-(2-tert-butylphenoxy)-N-(2-hydroxyethyl)-1,8-naphthalimide (2), and 4-[2,4-di(tert-butyl)]phenoxy-N-(2-hydroxyethyl)-1,8-naphthalimide (3), are investigated by density functional theory (DFT) and time-dependent density functional theory (TD-DFT) calculations in conjunction with polarizable continuum models (PCMs). Four functionals and ten basis sets are employed for 1 to calculate the electron transition energies, which were compared with the experimental observations. Our results reveal that the B3LYP/6-311+G(d,p) method is the best choice to reproduce the experimental spectra. Moreover, the effects of substituents on the molecular geometries, electronic structures, absorption and emission spectra are also studied at the B3LYP/6-311+G(d,p) level. We find that the gap between the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) decreases with increasing the number of tert-butyl substituents onto the phenoxy groups, suggesting red-shift of the absorption and emission bands. This is related to the increase of conjugation from 1 to 2 and 3. Our calculations are in good agreement with the experimental results.
2014, 33(6): 821-829
Abstract:
The photochromic mechanism of 1-phenyl-3-methyl-4-(6-hydro-4-amino-5-sulfo-2,3-pyrazine)-pyrazole-5-one has been investigated using the density functional theory (DFT). The solvent effect is simulated using the polarizable continuum model (PCM) of the self-consistent reaction field theory. According to the crystal structure of the title compound, an intramolecular proton transfer mechanism from enol to keto form was proposed to interpret its photochromism. Bader's atom-in-molecule (AIM) theory is used to investigate the nature of hydrogen bonds and ring structures. Time-dependent density functional theory (TDDFT) calculation results show that the photochromic process from enol to keto form is reasonable. The conformation and molecular orbital analysis of enol and keto forms explain why only intramolecular proton transfer is possible. The results from analyzing the energy and dipole moments of enol form, transition state and keto form in the gas phase and in different solvents have been used to assess the stability of the title compound.
The photochromic mechanism of 1-phenyl-3-methyl-4-(6-hydro-4-amino-5-sulfo-2,3-pyrazine)-pyrazole-5-one has been investigated using the density functional theory (DFT). The solvent effect is simulated using the polarizable continuum model (PCM) of the self-consistent reaction field theory. According to the crystal structure of the title compound, an intramolecular proton transfer mechanism from enol to keto form was proposed to interpret its photochromism. Bader's atom-in-molecule (AIM) theory is used to investigate the nature of hydrogen bonds and ring structures. Time-dependent density functional theory (TDDFT) calculation results show that the photochromic process from enol to keto form is reasonable. The conformation and molecular orbital analysis of enol and keto forms explain why only intramolecular proton transfer is possible. The results from analyzing the energy and dipole moments of enol form, transition state and keto form in the gas phase and in different solvents have been used to assess the stability of the title compound.
2014, 33(6): 830-834
Abstract:
Density functional theory (DFT)-B3LYP level with the 6-311G**(d,p) basis set was used to calculate a set of molecular quantum chemical descriptors of 12 chloroanilines. Quantitative structure-activity relationship (QSAR) models of the bioconcentration factors (BCF) of the anilines in fish were established using some of the following calculated descriptors: EHOMO, ENHOMO, ELUMO, ENLUMO, ΔE1(=ELUMO-EHOMO), ΔE2(=ENLUMO-ENHOMO), dipole moment (μ), molecular volume (V), vibrational energy of 0 K (Ev), thermodynamic energy (E), heat capacity (Cv), entropy (Sm) and the charge of benzene ring (Qph). Using the variable selection and leaps-and-bounds regression, the quantum chemical descriptors derived directly from the molecular structures were employed to develop a linear QSAR model between the bioconcentration factors (BCF) and two descriptors (Sm, ENHOMO) of 12 chloroanilines. Statistically, the most significant one is a two-parameter linear equation with the correlation coefficient (R2) of 0.981 and cross-validated correlation coefficient (RCV2) of 0.967. The established QSAR model has good stability and predictability based on the results from RCV2 of leave-one-out cross-validation, AIC, FIT and tα/2. The quantum chemical analyses were performed from two aspects of frontier molecular orbital and entropy. The results show that two structural describers are crucial to the bioconcentration activity of chloroanilines.
Density functional theory (DFT)-B3LYP level with the 6-311G**(d,p) basis set was used to calculate a set of molecular quantum chemical descriptors of 12 chloroanilines. Quantitative structure-activity relationship (QSAR) models of the bioconcentration factors (BCF) of the anilines in fish were established using some of the following calculated descriptors: EHOMO, ENHOMO, ELUMO, ENLUMO, ΔE1(=ELUMO-EHOMO), ΔE2(=ENLUMO-ENHOMO), dipole moment (μ), molecular volume (V), vibrational energy of 0 K (Ev), thermodynamic energy (E), heat capacity (Cv), entropy (Sm) and the charge of benzene ring (Qph). Using the variable selection and leaps-and-bounds regression, the quantum chemical descriptors derived directly from the molecular structures were employed to develop a linear QSAR model between the bioconcentration factors (BCF) and two descriptors (Sm, ENHOMO) of 12 chloroanilines. Statistically, the most significant one is a two-parameter linear equation with the correlation coefficient (R2) of 0.981 and cross-validated correlation coefficient (RCV2) of 0.967. The established QSAR model has good stability and predictability based on the results from RCV2 of leave-one-out cross-validation, AIC, FIT and tα/2. The quantum chemical analyses were performed from two aspects of frontier molecular orbital and entropy. The results show that two structural describers are crucial to the bioconcentration activity of chloroanilines.
2014, 33(6): 835-840
Abstract:
Two new organic supramolecular cocrystal complexes C18H18O4·C10H8N2 (Ⅰ) and C18H18O4·C12H10N2 (Ⅱ) (C18H18O4=2,3,6,7-tetrahydroxyl-9,10-dimethyl-9,10-dihydro-9,10-ethanoanthracene (LH4), C10H8N2=4,4'-bipyridine (bpy) and C12H10N2=4,4'-bipyridinylethane (bpe)) have been obtained by mixing LH4 with corresponding bpy or bpe ligand. The two complexes have been determined by X-ray crystal structure analysis, elemental analysis and IR analysis. Compound Ⅰ crystallizes in the orthorhombic Pnma with a=9.7078(4), b=22.4974(10), c=20.6272(9)Å, V=4505.0(3)Å3, Mr=454.51, Dc=1.340 g·cm-3, μ=0.09 mm-1, F(000)=1920, Z=8, R=0.0503 and wR=0.1360. Compound Ⅱ crystallizes in monoclinic C2/c with a=29.944(6), b=9.820(2), c=22.643(5)Å, V=5048.4(18)Å3, Mr=480.54, Dc=1.265 g cm-3, μ=0.084 mm-1, F(000)=2032, Z=8, R=0.0548 and wR=0.1600. X-ray single-crystal structure analysis shows that two-dimensional (2D) layer supramolecular structures are formed through hydrogen bonds and π-π interactions in the two complexes. IR analysis also indicates that there are only associated hydroxyl groups in the two complexes.
Two new organic supramolecular cocrystal complexes C18H18O4·C10H8N2 (Ⅰ) and C18H18O4·C12H10N2 (Ⅱ) (C18H18O4=2,3,6,7-tetrahydroxyl-9,10-dimethyl-9,10-dihydro-9,10-ethanoanthracene (LH4), C10H8N2=4,4'-bipyridine (bpy) and C12H10N2=4,4'-bipyridinylethane (bpe)) have been obtained by mixing LH4 with corresponding bpy or bpe ligand. The two complexes have been determined by X-ray crystal structure analysis, elemental analysis and IR analysis. Compound Ⅰ crystallizes in the orthorhombic Pnma with a=9.7078(4), b=22.4974(10), c=20.6272(9)Å, V=4505.0(3)Å3, Mr=454.51, Dc=1.340 g·cm-3, μ=0.09 mm-1, F(000)=1920, Z=8, R=0.0503 and wR=0.1360. Compound Ⅱ crystallizes in monoclinic C2/c with a=29.944(6), b=9.820(2), c=22.643(5)Å, V=5048.4(18)Å3, Mr=480.54, Dc=1.265 g cm-3, μ=0.084 mm-1, F(000)=2032, Z=8, R=0.0548 and wR=0.1600. X-ray single-crystal structure analysis shows that two-dimensional (2D) layer supramolecular structures are formed through hydrogen bonds and π-π interactions in the two complexes. IR analysis also indicates that there are only associated hydroxyl groups in the two complexes.
2014, 33(6): 841-845
Abstract:
The title compound 4-chloro-2-(morpholine-4-carbonyl)phenyl-4'-methoxybenzoate (C19H18ClNO5, Mr=375.79), a 5-chlorosalicylic acid derivative incorporating morpholine moiety, was conveniently synthesized through two steps and crystallized in the monoclinic space group P21/c with a=7.8501(10), b=9.3149(12), c=25.133(3)Å, V=1836.2(4)Å3, Z=4, Dc=1.359 Mg/m3, λ=0.71073Å, μ(MoKα)=0.237 mm-1, F(000)=784, R=0.0447 and wR=0.1227 for 3982 independent reflections with I>2σ(I). The dihedral angles formed between 4-methoxybenzene and 5-chlorobenzene rings, the 5-chlorobenzene and morpholine, and 4-methoxybenzene and morpholine rings are 82.55(3), 72.56(5) and 47.68(0)° by X-ray analysis, respectively. Bioassay shows that the title compound has a good molluscidal effect.
The title compound 4-chloro-2-(morpholine-4-carbonyl)phenyl-4'-methoxybenzoate (C19H18ClNO5, Mr=375.79), a 5-chlorosalicylic acid derivative incorporating morpholine moiety, was conveniently synthesized through two steps and crystallized in the monoclinic space group P21/c with a=7.8501(10), b=9.3149(12), c=25.133(3)Å, V=1836.2(4)Å3, Z=4, Dc=1.359 Mg/m3, λ=0.71073Å, μ(MoKα)=0.237 mm-1, F(000)=784, R=0.0447 and wR=0.1227 for 3982 independent reflections with I>2σ(I). The dihedral angles formed between 4-methoxybenzene and 5-chlorobenzene rings, the 5-chlorobenzene and morpholine, and 4-methoxybenzene and morpholine rings are 82.55(3), 72.56(5) and 47.68(0)° by X-ray analysis, respectively. Bioassay shows that the title compound has a good molluscidal effect.
2014, 33(6): 846-850
Abstract:
The crystal structure of the title compound (C24H22N2O5, Mr=418.44) has been determined by single-crystal X-ray diffraction. The crystal is of orthorhombic, space group P21/c with a=7.751(2), b=12.392(4), c=21.326(6)Å, V=2048.4(1)Å3, Z=4, Dc=1.357 g/cm3, F(000)=880, μ(MoKα)=0.096 mm-1, the final R=0.0731 and wR=0.1982 for 3335 observed reflections (I>2σ(I)). Intermolecular C(24)-H(24B)…O(1) hydrogen bond is observed in the structure.
The crystal structure of the title compound (C24H22N2O5, Mr=418.44) has been determined by single-crystal X-ray diffraction. The crystal is of orthorhombic, space group P21/c with a=7.751(2), b=12.392(4), c=21.326(6)Å, V=2048.4(1)Å3, Z=4, Dc=1.357 g/cm3, F(000)=880, μ(MoKα)=0.096 mm-1, the final R=0.0731 and wR=0.1982 for 3335 observed reflections (I>2σ(I)). Intermolecular C(24)-H(24B)…O(1) hydrogen bond is observed in the structure.
2014, 33(6): 851-854
Abstract:
The title compound (S)-N-(hexahydro-2-oxo-1H-azepin-3-yl)-3-phenyl-2-propenamide (C15H18N2O2, Mr=258.31) was synthesized by the reaction of (S)-α-amino-ε-caprolactam with 3-phenyl-2-propenoyl chloride. Its chemical structure was determined by 1H NMR, 13C NMR, H RMS and X-ray single-crystal diffraction. The crystal belongs to the monoclinic system, space group P21/c with a=14.957(3), b=4.884(1), c=18.630(4)Å, β=95.91(3)°, V=1353.7(5)Å3, Z=4, Dc=1.267 g/cm3, μ=0.085 mm-1, F(000)=552, R=0.0671 and wR=0.1547 for 2473 observed reflections with I>2σ(I).
The title compound (S)-N-(hexahydro-2-oxo-1H-azepin-3-yl)-3-phenyl-2-propenamide (C15H18N2O2, Mr=258.31) was synthesized by the reaction of (S)-α-amino-ε-caprolactam with 3-phenyl-2-propenoyl chloride. Its chemical structure was determined by 1H NMR, 13C NMR, H RMS and X-ray single-crystal diffraction. The crystal belongs to the monoclinic system, space group P21/c with a=14.957(3), b=4.884(1), c=18.630(4)Å, β=95.91(3)°, V=1353.7(5)Å3, Z=4, Dc=1.267 g/cm3, μ=0.085 mm-1, F(000)=552, R=0.0671 and wR=0.1547 for 2473 observed reflections with I>2σ(I).
2014, 33(6): 855-858
Abstract:
The title compound was synthesized by the reaction of 4-tert-butyl-5-(4-chlorobenzyl)-2-aminothiazole with 2,6-difluorobenzoic acid. The crystal structure of the title compound, C21H19ClF2N2OS, was determined by single-crystal X-ray diffraction. The crystal belongs to the triclinic system, space group Pbca with a=12.6479(13), b=13.1204(13), c=14.1341(15)Å, Z=4, V=2011.5(4)Å3, Mr=420.89, Dc=1.390 g/cm3, S=1.023, μ=0.326 mm-1, F(000)=872, the final R=0.0365 and wR=0.0880 for 6101 observed reflections (I>2σ(I)), and R=0.0507, wR=0.0978 for 7779 independent reflections. X-ray crystal structure displays that the hydrogen bonding interactions observed link the molecules to form a dimeric unit. The preliminary biological test of the title compound shows good antitumor activity, with IC50 of 0.046 μmol/mL against the Hela cell line.
The title compound was synthesized by the reaction of 4-tert-butyl-5-(4-chlorobenzyl)-2-aminothiazole with 2,6-difluorobenzoic acid. The crystal structure of the title compound, C21H19ClF2N2OS, was determined by single-crystal X-ray diffraction. The crystal belongs to the triclinic system, space group Pbca with a=12.6479(13), b=13.1204(13), c=14.1341(15)Å, Z=4, V=2011.5(4)Å3, Mr=420.89, Dc=1.390 g/cm3, S=1.023, μ=0.326 mm-1, F(000)=872, the final R=0.0365 and wR=0.0880 for 6101 observed reflections (I>2σ(I)), and R=0.0507, wR=0.0978 for 7779 independent reflections. X-ray crystal structure displays that the hydrogen bonding interactions observed link the molecules to form a dimeric unit. The preliminary biological test of the title compound shows good antitumor activity, with IC50 of 0.046 μmol/mL against the Hela cell line.
2014, 33(6): 859-864
Abstract:
The new title compound 8-((4-((2,3-diaminopyridin-4-yl)-oxy)-3-fluorophenyl)-amino)-2-(4-fluorophenyl)-3-methyl-2,7-naphthyridin-1(2H)-one (C26H20F2N6O2, Mr=486.48) has been prepared and determined by single-crystal X-ray diffraction. The crystal is of monoclinic, space group P21/c with a=15.365(3), b=13.144(2), c=11.863(2)Å, β=108.882(3)°, Z=4, V=2267.0(7)Å3, Dc=1.425 g/cm3, F(000)=1008, μ=0.105 mm-1, MoKa radiation (λ=0.71073Å), R=0.0480 and wR=0.1294 for 3197 observed reflections with I>2σ(I). X-ray diffraction analysis reveals that the region C (substituents of 8-amino group and 3-methyl group on the 2,7-naphthyridin-1(2H)-one ring) of compound 6 are effectively planar. Intramolecular and intermolecular hydrogen bonds together with π…π interations are found in the structure. In addition, compound 6 shows potent c-Met and c-Kit kinase inhibition activities.
The new title compound 8-((4-((2,3-diaminopyridin-4-yl)-oxy)-3-fluorophenyl)-amino)-2-(4-fluorophenyl)-3-methyl-2,7-naphthyridin-1(2H)-one (C26H20F2N6O2, Mr=486.48) has been prepared and determined by single-crystal X-ray diffraction. The crystal is of monoclinic, space group P21/c with a=15.365(3), b=13.144(2), c=11.863(2)Å, β=108.882(3)°, Z=4, V=2267.0(7)Å3, Dc=1.425 g/cm3, F(000)=1008, μ=0.105 mm-1, MoKa radiation (λ=0.71073Å), R=0.0480 and wR=0.1294 for 3197 observed reflections with I>2σ(I). X-ray diffraction analysis reveals that the region C (substituents of 8-amino group and 3-methyl group on the 2,7-naphthyridin-1(2H)-one ring) of compound 6 are effectively planar. Intramolecular and intermolecular hydrogen bonds together with π…π interations are found in the structure. In addition, compound 6 shows potent c-Met and c-Kit kinase inhibition activities.
2014, 33(6): 865-870
Abstract:
The title complex (C66H76O8·CH3CN) was synthesized and structurally determined by single-crystal X-ray diffraction method. It crystallizes in monoclinic, space group P21/c with a=22.384(13), b=13.413(7), c=21.867(12)Å, β=112.257(7)°, C68H78NO8, Mr=1037.31, Dc=1.133 g/cm3, V=6076(6)Å3, Z=4, F(000)=2224, μ(MoKa)=0.073 mm-1, T=296(2) K, 10276 independent reflections with 5469 observed ones (I>2σ(I)), R=0.0797 and wR=0.2316 with GOF=1.027 (R=0.1442 and wR=0.2689 for all data). The calixarene moiety maintains the symmetric cone conformation through intramolecular O-H…O hydrogen bonds. The inhibition of the strand transfer process of HIV-1 integrase of the title compound was also evaluated. Preliminary bioassays indicated that it has a low inhibition ratio (24.85%) at the concentration of 50 μM.
The title complex (C66H76O8·CH3CN) was synthesized and structurally determined by single-crystal X-ray diffraction method. It crystallizes in monoclinic, space group P21/c with a=22.384(13), b=13.413(7), c=21.867(12)Å, β=112.257(7)°, C68H78NO8, Mr=1037.31, Dc=1.133 g/cm3, V=6076(6)Å3, Z=4, F(000)=2224, μ(MoKa)=0.073 mm-1, T=296(2) K, 10276 independent reflections with 5469 observed ones (I>2σ(I)), R=0.0797 and wR=0.2316 with GOF=1.027 (R=0.1442 and wR=0.2689 for all data). The calixarene moiety maintains the symmetric cone conformation through intramolecular O-H…O hydrogen bonds. The inhibition of the strand transfer process of HIV-1 integrase of the title compound was also evaluated. Preliminary bioassays indicated that it has a low inhibition ratio (24.85%) at the concentration of 50 μM.
2014, 33(6): 871-875
Abstract:
The crystal structure of the title compound (C24H24N2O5, Mr=420.45) has been determined by single-crystal X-ray diffraction. The crystal is of triclinic, space group P1 with a=8.991(1), b=11.166(1), c=11.169(1)Å, α=91.413(2), β=105.887(2), γ=90.992(2)°, V=1077.8(2)Å3, Z=2, Dc=1.296 g/cm3, F(000)=444, μ(MoKα)=0.091 mm-1, the final R=0.0466 and wR=0.1507 for 4185 observed reflections (I>2σ(I)). The single-crystal X-ray diffraction data indicated intermolecular C(17)-H(17)…O(4), C(5)-H(5)…O(4) hydrogen bonds and C-H…π interaction in the structure.
The crystal structure of the title compound (C24H24N2O5, Mr=420.45) has been determined by single-crystal X-ray diffraction. The crystal is of triclinic, space group P1 with a=8.991(1), b=11.166(1), c=11.169(1)Å, α=91.413(2), β=105.887(2), γ=90.992(2)°, V=1077.8(2)Å3, Z=2, Dc=1.296 g/cm3, F(000)=444, μ(MoKα)=0.091 mm-1, the final R=0.0466 and wR=0.1507 for 4185 observed reflections (I>2σ(I)). The single-crystal X-ray diffraction data indicated intermolecular C(17)-H(17)…O(4), C(5)-H(5)…O(4) hydrogen bonds and C-H…π interaction in the structure.
2014, 33(6): 876-880
Abstract:
Many small-molecule compounds have been evaluated with potential antiproliferative activities. Ethyl 1-(phenylcarbamoyl)-2-(3,4,5-trimethoxyphenyl)cyclopropanecarboxylate, one novel cyclopropylamide analogue of combretastatin-A4 (CA-4), has been synthesized and its crystal structure was characterized by X-ray single-crystal diffraction. The crystal belongs to monoclinic, space group P21/c, with a=15.0263(3), b=7.6574(2), c=19.4117(4)Å, β=111.9010(10)°, V=2072.36(8)Å3, Z=4, C22H24NO6, Mr=398.42, Dc=1.277 Mg/cm3, F(000)=844, λ(MoKα)=1.54178Å, μ=0.770 mm-1, R=0.0546 and wR=0.1889 for 3319 observed reflections (I>2σ(I)). Meanwhile, the compound revealed potential antiproliferative activities in several cancer cells in vitro.
Many small-molecule compounds have been evaluated with potential antiproliferative activities. Ethyl 1-(phenylcarbamoyl)-2-(3,4,5-trimethoxyphenyl)cyclopropanecarboxylate, one novel cyclopropylamide analogue of combretastatin-A4 (CA-4), has been synthesized and its crystal structure was characterized by X-ray single-crystal diffraction. The crystal belongs to monoclinic, space group P21/c, with a=15.0263(3), b=7.6574(2), c=19.4117(4)Å, β=111.9010(10)°, V=2072.36(8)Å3, Z=4, C22H24NO6, Mr=398.42, Dc=1.277 Mg/cm3, F(000)=844, λ(MoKα)=1.54178Å, μ=0.770 mm-1, R=0.0546 and wR=0.1889 for 3319 observed reflections (I>2σ(I)). Meanwhile, the compound revealed potential antiproliferative activities in several cancer cells in vitro.
2014, 33(6): 881-887
Abstract:
In this work, we demonstrate an in situ phase conversion from basic magnesium chloride (BMC) into magnesium hydroxide whisker by using polar organic solvent at low temperature. The morphology and phase composition of magnesium hydroxide whiskers prepared at different reaction temperature, alkali concentration and organic solvent were analyzed by X-ray diffraction (XRD) and scanning electronic microscope (SEM). It was found that when one of the organic solvents such as absolute ethyl alcohol, butanol, polyethylene glycol (PEG-400), acetone, et al. was selected as the template, the precursor BMC can transform into whisker-like magnesium hydroxide through precipitate transformation in low temperature and non-hydrothermal system. It can be reasonably explained that the regulation of Mg2+ solubility by those organic solvents and the sustained release of Mg2+ dissolution by organic adsorption played a significant role in the formation of magnesium hydroxide whisker via BMC whisker as the precursor.
In this work, we demonstrate an in situ phase conversion from basic magnesium chloride (BMC) into magnesium hydroxide whisker by using polar organic solvent at low temperature. The morphology and phase composition of magnesium hydroxide whiskers prepared at different reaction temperature, alkali concentration and organic solvent were analyzed by X-ray diffraction (XRD) and scanning electronic microscope (SEM). It was found that when one of the organic solvents such as absolute ethyl alcohol, butanol, polyethylene glycol (PEG-400), acetone, et al. was selected as the template, the precursor BMC can transform into whisker-like magnesium hydroxide through precipitate transformation in low temperature and non-hydrothermal system. It can be reasonably explained that the regulation of Mg2+ solubility by those organic solvents and the sustained release of Mg2+ dissolution by organic adsorption played a significant role in the formation of magnesium hydroxide whisker via BMC whisker as the precursor.
2014, 33(6): 888-896
Abstract:
Two coordination polymers, namely [Pb(Hbtc)(phen)]n (1) and {[Cd3(btc)2(H2O)4]·2H2O}n (2, H3btc=biphenyl-2,5,3'-tricarboxylic acid, phen=1,10-phenanthroline), were assembled. Single-crystal X-ray diffraction studies show that compound 1 possesses a zigzag chain 1D coordination network, which is further extended into a 3D supramolecular architecture via O-H…O hydrogen bonds and π-π packing interactions. Compound 2 features a 3D open framework based on a tricadmium(Ⅱ) subunit, generating a trinodal 4,4,6-connected net with the 4,4,6T24 topology defined by the point symbol of (44·62)3(46·69)2. Thermal stability and luminescent properties of both compounds were studied and discussed.
Two coordination polymers, namely [Pb(Hbtc)(phen)]n (1) and {[Cd3(btc)2(H2O)4]·2H2O}n (2, H3btc=biphenyl-2,5,3'-tricarboxylic acid, phen=1,10-phenanthroline), were assembled. Single-crystal X-ray diffraction studies show that compound 1 possesses a zigzag chain 1D coordination network, which is further extended into a 3D supramolecular architecture via O-H…O hydrogen bonds and π-π packing interactions. Compound 2 features a 3D open framework based on a tricadmium(Ⅱ) subunit, generating a trinodal 4,4,6-connected net with the 4,4,6T24 topology defined by the point symbol of (44·62)3(46·69)2. Thermal stability and luminescent properties of both compounds were studied and discussed.
2014, 33(6): 897-902
Abstract:
A new cobalt(Ⅱ) complex [Co(NO2-salen)2]·1.5H2O containing mono acetalization Schiff base ligand (NO2-salen=N-5-nitro-salicylideneamino ethanato) has been prepared through one-pot template condensation, and has been structurally characterized by elemental analysis, IR spectra and X-ray diffraction. It is formulated as C18H23CoN6O7.5, crystallizes in the hexagonal system, space group of R-3c with α=25.895(18), b=25.895(18), c=35.075(6)Å, γ=120°, V=20368(3)Å and Z=36. The ligand of 5-nitrosalicylaldehyde-ethylene-diamine takes unusual mono asymmetry mode. The Co(Ⅱ) ion exhibits a coordination number of six, and assumes a distorted octahedral geometry with a N2O4 donor set. The neutral monomeric units of [Co(NO2-salen)2]·1.5H2O are linked into a one-dimensional (1D) structure via the intermolecular hydrogen bonds and weak π-π stacking interactions. Cyclic-voltammetry measurement reveals the oxidation and reduction processes for the complex are irreversible in nature.
A new cobalt(Ⅱ) complex [Co(NO2-salen)2]·1.5H2O containing mono acetalization Schiff base ligand (NO2-salen=N-5-nitro-salicylideneamino ethanato) has been prepared through one-pot template condensation, and has been structurally characterized by elemental analysis, IR spectra and X-ray diffraction. It is formulated as C18H23CoN6O7.5, crystallizes in the hexagonal system, space group of R-3c with α=25.895(18), b=25.895(18), c=35.075(6)Å, γ=120°, V=20368(3)Å and Z=36. The ligand of 5-nitrosalicylaldehyde-ethylene-diamine takes unusual mono asymmetry mode. The Co(Ⅱ) ion exhibits a coordination number of six, and assumes a distorted octahedral geometry with a N2O4 donor set. The neutral monomeric units of [Co(NO2-salen)2]·1.5H2O are linked into a one-dimensional (1D) structure via the intermolecular hydrogen bonds and weak π-π stacking interactions. Cyclic-voltammetry measurement reveals the oxidation and reduction processes for the complex are irreversible in nature.
2014, 33(6): 903-908
Abstract:
Two macrocyclic zinc(Ⅱ) complexes {[ZnL(VO3)2]·0.33H2O}n (1) and [ZnL(H2O)2][Ni(CN)4] (2) (L=5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane) have been obtained from the reactions of [ZnL](ClO4)2 with NH4VO3 and K2[Ni(CN)4], respectively, and structurally characterized by elemental analysis, IR, XRPD, TG and X-ray diffraction. Single-crystal X-ray diffraction analyses indicated that the Zn(Ⅱ) atom lies on an inversion center and is octahedrally coordinated by four nitrogen atoms of the tetradentate macrocyclic ligand in the equatorial plane and two oxygen atoms of [VO4] tetrahedra in the axial positions in 1, and two oxygen atoms of two water molecules in 2. Complex 1 shows a three-dimensional structure, which is constructed by the links of [VO3]nn- chains with [ZnL]2+, forming one-dimensional channels occupied by guest water molecules. The monomers of [ZnL(H2O)2]2+ and [Ni(CN)4]2- are connected through the intermolecular hydrogen bonds to form a two-dimensional sheet in complex 2.
Two macrocyclic zinc(Ⅱ) complexes {[ZnL(VO3)2]·0.33H2O}n (1) and [ZnL(H2O)2][Ni(CN)4] (2) (L=5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane) have been obtained from the reactions of [ZnL](ClO4)2 with NH4VO3 and K2[Ni(CN)4], respectively, and structurally characterized by elemental analysis, IR, XRPD, TG and X-ray diffraction. Single-crystal X-ray diffraction analyses indicated that the Zn(Ⅱ) atom lies on an inversion center and is octahedrally coordinated by four nitrogen atoms of the tetradentate macrocyclic ligand in the equatorial plane and two oxygen atoms of [VO4] tetrahedra in the axial positions in 1, and two oxygen atoms of two water molecules in 2. Complex 1 shows a three-dimensional structure, which is constructed by the links of [VO3]nn- chains with [ZnL]2+, forming one-dimensional channels occupied by guest water molecules. The monomers of [ZnL(H2O)2]2+ and [Ni(CN)4]2- are connected through the intermolecular hydrogen bonds to form a two-dimensional sheet in complex 2.
2014, 33(6): 909-914
Abstract:
The complex [Cd(bbb)Cl2]·DMF·H2O, where bbb is 2-(2-(1H-benzo[d]imidazol-2-yl)benzyl)-1H-benzo[d]imidazole, was synthesized and characterized by X-ray single-crystal structure analyses. For the complex: C24H25Cl2CdN5O2, Mr=598.77, crystal system, triclinic, space group P1, a=9.9878(12), b=10.0008(12), c=13.2217(15)Å, α=80.674(2), β=72.158(2), γ=86.776(2)°, V=1240.5(3)Å3, Z=2, Dc=1.598 g/cm3, λ=0.71073Å, μ(MoKα)=1.127 mm-1, F(000)=600, S=1.04, R=0.0905 and wR=0.3088 for 4805 observed reflections with I>2σ(I). It is a neutral complex. The distorted tetrahedral geometry of cadmium ion is coordinated by two nitrogen atoms of ligand and two chloride ions. The complex emits blue green luminescence with emission peaks at 480 nm in DMF solution.
The complex [Cd(bbb)Cl2]·DMF·H2O, where bbb is 2-(2-(1H-benzo[d]imidazol-2-yl)benzyl)-1H-benzo[d]imidazole, was synthesized and characterized by X-ray single-crystal structure analyses. For the complex: C24H25Cl2CdN5O2, Mr=598.77, crystal system, triclinic, space group P1, a=9.9878(12), b=10.0008(12), c=13.2217(15)Å, α=80.674(2), β=72.158(2), γ=86.776(2)°, V=1240.5(3)Å3, Z=2, Dc=1.598 g/cm3, λ=0.71073Å, μ(MoKα)=1.127 mm-1, F(000)=600, S=1.04, R=0.0905 and wR=0.3088 for 4805 observed reflections with I>2σ(I). It is a neutral complex. The distorted tetrahedral geometry of cadmium ion is coordinated by two nitrogen atoms of ligand and two chloride ions. The complex emits blue green luminescence with emission peaks at 480 nm in DMF solution.
2014, 33(6): 915-920
Abstract:
Two new coordination polymers {[Zn2L1(2,2'-bpy)2(H2O)2]·4H2O}n (1) and [Zn2L2(2,2'-bpy)2(H2O)2]n (2) (H4L1=terphenyl-2,2',4,4'-tetracarboxylic acid, H4L2=quarterphenyl-2,2',4,4'-tetracarboxylic acid, and 2,2'-bpy=2,2'-bipyridine) have been synthesized and characterized by elemental analysis, IR and X-ray single-crystal diffraction studies. Complex 1 displays 2D wavelike networks, which are further joined together through O-H…O hydrogen bonds to give a 3D supramolecular network. Complex 2 exhibits 1D ladder-like chains, and they are further joined together by π-π stacking and O-H…O hydrogen bonding interactions to form a 3D supramolecular network. The results indicate that the backbone of carboxylate ligands has significant effects on the formation and structure of the resulting functional coordination polymers. Additionally, thermal stability and photoluminescent properties of 1 and 2 are also investigated in detail.
Two new coordination polymers {[Zn2L1(2,2'-bpy)2(H2O)2]·4H2O}n (1) and [Zn2L2(2,2'-bpy)2(H2O)2]n (2) (H4L1=terphenyl-2,2',4,4'-tetracarboxylic acid, H4L2=quarterphenyl-2,2',4,4'-tetracarboxylic acid, and 2,2'-bpy=2,2'-bipyridine) have been synthesized and characterized by elemental analysis, IR and X-ray single-crystal diffraction studies. Complex 1 displays 2D wavelike networks, which are further joined together through O-H…O hydrogen bonds to give a 3D supramolecular network. Complex 2 exhibits 1D ladder-like chains, and they are further joined together by π-π stacking and O-H…O hydrogen bonding interactions to form a 3D supramolecular network. The results indicate that the backbone of carboxylate ligands has significant effects on the formation and structure of the resulting functional coordination polymers. Additionally, thermal stability and photoluminescent properties of 1 and 2 are also investigated in detail.
2014, 33(6): 921-927
Abstract:
A cluster compound V2S6O2Cu6(3-MePy)6 (3-MePy=3-methyl pyridine) has been synthesized by using skiving method and the crystal structure was characterized by X-ray diffraction: space group P1, Z=1, a=9.7278(4), b=10.4180(5), c=11.9230(6)Å, α=108.240(3), β=98.120(2), γ=99.500(2)°, R=0.052 and wR=0.104. The NLO properties were studied by Z-scan technique with 8 ns pulsed laser at 532 nm. The cluster exhibits strong NLO absorptive ability (α2=1.7×10-10 m·W-1) and effective self-focusing performance (n2=1.27×10-18 m2·W-1) in a 1.58×10-4 mol·dm-3 DMF solution.
A cluster compound V2S6O2Cu6(3-MePy)6 (3-MePy=3-methyl pyridine) has been synthesized by using skiving method and the crystal structure was characterized by X-ray diffraction: space group P1, Z=1, a=9.7278(4), b=10.4180(5), c=11.9230(6)Å, α=108.240(3), β=98.120(2), γ=99.500(2)°, R=0.052 and wR=0.104. The NLO properties were studied by Z-scan technique with 8 ns pulsed laser at 532 nm. The cluster exhibits strong NLO absorptive ability (α2=1.7×10-10 m·W-1) and effective self-focusing performance (n2=1.27×10-18 m2·W-1) in a 1.58×10-4 mol·dm-3 DMF solution.
2014, 33(6): 928-934
Abstract:
Two new Ag(Ⅰ) complexes {Ag2(L)(NO3)(H2O)}n (1) and {Ag(L)}n·nH2O (2) have been synthesized via the reaction of silver nitrate and betaine derivative 1-carboxymethylpyridinium-3-carboxylate (L) by only changing the metal-to-ligand ratio. The results of X-ray crystallographic analysis indicate that complexes 1 and 2 both crystallize in the monoclinic space group P21/c with a=5.0809(14), b=17.390(5), c=13.399(4)Å, β=91.677(5)°, V=1183.4(6)Å3, Z=4, Mr=475.90, Dc=2.671 g/cm3, F(000)=912, μ=3.352 mm-1, S=1.259, the final R=0.0320 and wR=0.0831 for 2036 observed reflections with I>2σ(I) for 1 and a=12.180(2), b=5.0283(10), c=14.396(3)Å, β=94.87(3)°, V=878.5(3)Å3, Z=4, Mr=306.02, Dc=2.314 g/cm3, F(000)=600, μ=2.294 mm-1, S=1.053, the final R=0.0283 and wR=0.0684 for 2011 observed reflections with I>2σ(I) for 2. Complexes 1 and 2 both feature a unique 2D structure. For 1, the 2D undulated network consists of 1D infinite helical chains running parallel to the b axis, while for 2, the 2D network is made up of 1D tubes along the b axis. Moreover, the Ag…Ag interactions in complexes 1 and 2 are also discussed.
Two new Ag(Ⅰ) complexes {Ag2(L)(NO3)(H2O)}n (1) and {Ag(L)}n·nH2O (2) have been synthesized via the reaction of silver nitrate and betaine derivative 1-carboxymethylpyridinium-3-carboxylate (L) by only changing the metal-to-ligand ratio. The results of X-ray crystallographic analysis indicate that complexes 1 and 2 both crystallize in the monoclinic space group P21/c with a=5.0809(14), b=17.390(5), c=13.399(4)Å, β=91.677(5)°, V=1183.4(6)Å3, Z=4, Mr=475.90, Dc=2.671 g/cm3, F(000)=912, μ=3.352 mm-1, S=1.259, the final R=0.0320 and wR=0.0831 for 2036 observed reflections with I>2σ(I) for 1 and a=12.180(2), b=5.0283(10), c=14.396(3)Å, β=94.87(3)°, V=878.5(3)Å3, Z=4, Mr=306.02, Dc=2.314 g/cm3, F(000)=600, μ=2.294 mm-1, S=1.053, the final R=0.0283 and wR=0.0684 for 2011 observed reflections with I>2σ(I) for 2. Complexes 1 and 2 both feature a unique 2D structure. For 1, the 2D undulated network consists of 1D infinite helical chains running parallel to the b axis, while for 2, the 2D network is made up of 1D tubes along the b axis. Moreover, the Ag…Ag interactions in complexes 1 and 2 are also discussed.
2014, 33(6): 935-941
Abstract:
Two 3D Ln-organic coordination frameworks (Ln=Pr3+ for 1 and Er3+ for 2) have been constructed. Single-crystal X-ray diffraction analysis reveals that the two complexes have similar structures and belong to the monoclinic C2/c space group. The trans-μ4-(η2:η1)-(η1:η1) 1,2-pda2- anions link the LnⅢ centers to generate a 2D network containing helical motif. The dimensionality is extended into a 3D architecture through cis-bis(μ2-η2:η1) 1,2-pda2- anions linking. The geometry of Ln3+ ions is single-capped anti-square prism. Two complexes were characterized by IR spectra and thermogravimetric analysis. The solid fluorescence of 1 and 2 was also investigated at room temperature.
Two 3D Ln-organic coordination frameworks (Ln=Pr3+ for 1 and Er3+ for 2) have been constructed. Single-crystal X-ray diffraction analysis reveals that the two complexes have similar structures and belong to the monoclinic C2/c space group. The trans-μ4-(η2:η1)-(η1:η1) 1,2-pda2- anions link the LnⅢ centers to generate a 2D network containing helical motif. The dimensionality is extended into a 3D architecture through cis-bis(μ2-η2:η1) 1,2-pda2- anions linking. The geometry of Ln3+ ions is single-capped anti-square prism. Two complexes were characterized by IR spectra and thermogravimetric analysis. The solid fluorescence of 1 and 2 was also investigated at room temperature.
2014, 33(6): 942-946
Abstract:
A novel compound, {[Cu2(nbdc)2(4,4'-bpy)2(H2O)2]·2H2O}n (H2nbdc=4-nitrobenzene-1,2-dicarboxylic acid, 4,4'-bpy=4,4'-bipyridine), was hydrothermally synthesized and characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis (TGA), and single-crystal X-ray diffraction. The complex is of orthorhombic system, space group Pbcn with a=32.222(7), b=7.8503(16), c=28.389(6)Å, V=7181(3)Å3, Dc=1.720 g/cm3, Mr=929.74, Z=8, F(000)=3792, μ=1.273 mm-1, the final R=0.0591 and wR=0.1378 for 4548 observed reflections with I>2σ(I). The compound exhibits a 3D self-penetrating framework with bcu net topology, in which the (46·48)-networks are joined by the H2nbdc and 4,4'-bpy linkers.
A novel compound, {[Cu2(nbdc)2(4,4'-bpy)2(H2O)2]·2H2O}n (H2nbdc=4-nitrobenzene-1,2-dicarboxylic acid, 4,4'-bpy=4,4'-bipyridine), was hydrothermally synthesized and characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis (TGA), and single-crystal X-ray diffraction. The complex is of orthorhombic system, space group Pbcn with a=32.222(7), b=7.8503(16), c=28.389(6)Å, V=7181(3)Å3, Dc=1.720 g/cm3, Mr=929.74, Z=8, F(000)=3792, μ=1.273 mm-1, the final R=0.0591 and wR=0.1378 for 4548 observed reflections with I>2σ(I). The compound exhibits a 3D self-penetrating framework with bcu net topology, in which the (46·48)-networks are joined by the H2nbdc and 4,4'-bpy linkers.
2014, 33(6): 947-951
Abstract:
A new complex has been synthesized with o-methylbenzoyl-benzoic acid (HL) and 1,10-phenanthroline (phen) in the mixture of water and ethanol. It crystallizes in monoclinic, space group C2/c with a=13.6328(18), b=17.7876(18), c=19.998(2)Å, β=104.720(4)°, C54H48N4O11Zn, Mr=994.33, V=4690.2(9)Å3, Dc=1.408 g/cm3, Z=4, F(000)=2072, μ(MoKα)=0.59 mm-1, R=0.0736 and wR=0.2029. The crystal structure shows that the zinc ions are coordinated with two oxygen atoms from two HL molecules and four nitrogen atoms from two phen molecules, forming distorted octahedral coordination geometry. The fluorescent and thermal stability properties of the complex are studied. The result shows that it has one fluorescent emission band at around 412 nm. In addition, the complex is stable under 210℃.
A new complex has been synthesized with o-methylbenzoyl-benzoic acid (HL) and 1,10-phenanthroline (phen) in the mixture of water and ethanol. It crystallizes in monoclinic, space group C2/c with a=13.6328(18), b=17.7876(18), c=19.998(2)Å, β=104.720(4)°, C54H48N4O11Zn, Mr=994.33, V=4690.2(9)Å3, Dc=1.408 g/cm3, Z=4, F(000)=2072, μ(MoKα)=0.59 mm-1, R=0.0736 and wR=0.2029. The crystal structure shows that the zinc ions are coordinated with two oxygen atoms from two HL molecules and four nitrogen atoms from two phen molecules, forming distorted octahedral coordination geometry. The fluorescent and thermal stability properties of the complex are studied. The result shows that it has one fluorescent emission band at around 412 nm. In addition, the complex is stable under 210℃.
