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2013 Volume 24 Issue 3
2013, 24(3): 177-182
Abstract:
In this review, a group of two-dimensional (2D) hydrogen-bonded supramolecular networks developed in our laboratory are discussed. Our attention ismainly focused on: (1) recognition of Fe3+ through twocomponent molecular networks; (2) site-selective fabrication of 2D fullerene arrays; and (3) fabrication of the nanoporous structure regulated by photoisomerization reaction process. It is envisioned that special supramolecular nanostructures, through H-bonding interactions, can be constructed or reconstructed to be further investigated toward the research of multi-component systems, molecule recognition, single molecular switches, and host-guest supramolecular chemistry.
In this review, a group of two-dimensional (2D) hydrogen-bonded supramolecular networks developed in our laboratory are discussed. Our attention ismainly focused on: (1) recognition of Fe3+ through twocomponent molecular networks; (2) site-selective fabrication of 2D fullerene arrays; and (3) fabrication of the nanoporous structure regulated by photoisomerization reaction process. It is envisioned that special supramolecular nanostructures, through H-bonding interactions, can be constructed or reconstructed to be further investigated toward the research of multi-component systems, molecule recognition, single molecular switches, and host-guest supramolecular chemistry.
2013, 24(3): 183-185
Abstract:
A series of novel acylide derivatives have been synthesized from clarithromycin A via a facile procedure. The C-3 modifications involved replacing the natural C-3 cladinosyl group in clarithromycin core with different aryl-piperzine sidechain via chemical synthesis. Meanwhile a distinctive intermediate with 10,11-epoxy moiety was obtained. The structure and stereochemistry of this novel structure were confirmed via NMR and X-ray crystallography. Potential anti-bacterial activities against both Grampositive and Gram-negative bacteria were reported. Because of existence of C10,11-epoxide, these derivatives can be used as intermediates for further structural modification.
A series of novel acylide derivatives have been synthesized from clarithromycin A via a facile procedure. The C-3 modifications involved replacing the natural C-3 cladinosyl group in clarithromycin core with different aryl-piperzine sidechain via chemical synthesis. Meanwhile a distinctive intermediate with 10,11-epoxy moiety was obtained. The structure and stereochemistry of this novel structure were confirmed via NMR and X-ray crystallography. Potential anti-bacterial activities against both Grampositive and Gram-negative bacteria were reported. Because of existence of C10,11-epoxide, these derivatives can be used as intermediates for further structural modification.
2013, 24(3): 186-188
Abstract:
A series of novel dinuclear platinum(Ⅱ) complexes with (1S, 3S)-1,2,3,4-tetrahydroisoquinolines as the ligands were synthesized as potential anticancer agents in several steps starting from commercially available L-DOPA. The cytotoxicities of the series of dinuclear platinum(Ⅱ) complexes of tetrahydroisoquinoline were tested against HCT-8, BEL-7402, A2780, MCF-7, Hela, A549 and BGC-823 cell lines by the MTT test. These complexes showed selective inhibition activity against cisplatin-insensitive cell line Skov3.
A series of novel dinuclear platinum(Ⅱ) complexes with (1S, 3S)-1,2,3,4-tetrahydroisoquinolines as the ligands were synthesized as potential anticancer agents in several steps starting from commercially available L-DOPA. The cytotoxicities of the series of dinuclear platinum(Ⅱ) complexes of tetrahydroisoquinoline were tested against HCT-8, BEL-7402, A2780, MCF-7, Hela, A549 and BGC-823 cell lines by the MTT test. These complexes showed selective inhibition activity against cisplatin-insensitive cell line Skov3.
2013, 24(3): 189-191
Abstract:
Three switchable macrocycles based on photochromic dithienylethene were synthesized under the template of dibenzylammonium hexafluorophosphate. Their structure were well-confirmed by NMR, ESI-MS and X-ray diffraction. Their photochromism indicated that they showed good reversibility in solution. Additionally, the theoretical calculation suggested that photoirradiation can change the cavity of macrocycles.
Three switchable macrocycles based on photochromic dithienylethene were synthesized under the template of dibenzylammonium hexafluorophosphate. Their structure were well-confirmed by NMR, ESI-MS and X-ray diffraction. Their photochromism indicated that they showed good reversibility in solution. Additionally, the theoretical calculation suggested that photoirradiation can change the cavity of macrocycles.
2013, 24(3): 192-194
Abstract:
Several N-alkyl/aryl-Se-alkyl/(aryl)selenocarbamates were prepared from various isocyanates and diselenides by reductive cleavage of Se-Se bond with the Zn/AlCl3 system in dry acetonitrile at 80℃.
Several N-alkyl/aryl-Se-alkyl/(aryl)selenocarbamates were prepared from various isocyanates and diselenides by reductive cleavage of Se-Se bond with the Zn/AlCl3 system in dry acetonitrile at 80℃.
2013, 24(3): 195-198
Abstract:
An efficient and multicomponent method has been developed for the synthesis of functionalized tricarboxamides at room temperature using CuI nanoparticles as catalyst. This method involved fivecomponent coupling reactions of Meldrum's acid, isocyanides with aromatic aldehydes and amines at room temperature. Atom economy, wide range of products, excellent yields in short time and mild reaction conditions are some of the important features of this protocol. Notably, this catalyst could be recycled and reused for several times without significantly decreasing the catalytic activity.
An efficient and multicomponent method has been developed for the synthesis of functionalized tricarboxamides at room temperature using CuI nanoparticles as catalyst. This method involved fivecomponent coupling reactions of Meldrum's acid, isocyanides with aromatic aldehydes and amines at room temperature. Atom economy, wide range of products, excellent yields in short time and mild reaction conditions are some of the important features of this protocol. Notably, this catalyst could be recycled and reused for several times without significantly decreasing the catalytic activity.
2013, 24(3): 199-201
Abstract:
An efficient two-step method was described for the synthesis of chromeno[3',4':5,6]pyrano[2,3-b]indole derivatives. The three-component reaction of 4-hydroxycoumarin, variously substituted benzaldehydes and indolin-2-one was promoted by P2O5 in refluxing ethanol to give trimolecular adducts, which were then cyclized in 1,2-dichloroethane under reflux using POCl3.
An efficient two-step method was described for the synthesis of chromeno[3',4':5,6]pyrano[2,3-b]indole derivatives. The three-component reaction of 4-hydroxycoumarin, variously substituted benzaldehydes and indolin-2-one was promoted by P2O5 in refluxing ethanol to give trimolecular adducts, which were then cyclized in 1,2-dichloroethane under reflux using POCl3.
2013, 24(3): 202-204
Abstract:
An efficient synthesis of 4,5-diamino-3-halofuran-2(5H)-ones has been developed based on a sequential acylation and bisamination of mucohalic acids. The β-and γ-amination products have also been prepared with high regioselectivity. This reaction shows some advantages in terms of its simple operation and readily available but highly functionalized starting material. All products gave satisfactory IR, 1H NMR, 13C NMR and HRMS.
An efficient synthesis of 4,5-diamino-3-halofuran-2(5H)-ones has been developed based on a sequential acylation and bisamination of mucohalic acids. The β-and γ-amination products have also been prepared with high regioselectivity. This reaction shows some advantages in terms of its simple operation and readily available but highly functionalized starting material. All products gave satisfactory IR, 1H NMR, 13C NMR and HRMS.
2013, 24(3): 205-207
Abstract:
The electrochemical oxidation of 2,5-dihydroxybenzoic acid (1) has been studied in the presence of 1,3-cyclopentadiene (2) as a diene in water/ethanol (40/60, v/v) mixture using cyclic voltammetry and controlled-potential coulometry. A plausible mechanism for the oxidation of 1 in the presence of 2 is presented. Compound 1 was converted into bis-adduct 5 via electrooxidation, Diels-Alder reaction of 2 to anodically generated 3,6-dioxocyclohexa-1,4-dienecarboxylic acid (1ox), decarboxylation reaction, electrooxidation and Diels-Alder reaction. The electrochemical synthesis of 5 was performed in a onepot reaction, without toxic reagents, at a carbon electrode in a simple cell using an environmentally friendly method.
The electrochemical oxidation of 2,5-dihydroxybenzoic acid (1) has been studied in the presence of 1,3-cyclopentadiene (2) as a diene in water/ethanol (40/60, v/v) mixture using cyclic voltammetry and controlled-potential coulometry. A plausible mechanism for the oxidation of 1 in the presence of 2 is presented. Compound 1 was converted into bis-adduct 5 via electrooxidation, Diels-Alder reaction of 2 to anodically generated 3,6-dioxocyclohexa-1,4-dienecarboxylic acid (1ox), decarboxylation reaction, electrooxidation and Diels-Alder reaction. The electrochemical synthesis of 5 was performed in a onepot reaction, without toxic reagents, at a carbon electrode in a simple cell using an environmentally friendly method.
2013, 24(3): 208-210
Abstract:
Poly(4-vinylpyridine) is reported as a green, commercial available and efficient basic recyclable catalyst for the synthesis of chromene derivatives. This catalyst can be easily recovered by simple filtration and recycled up to 5 consecutive runs without any loss of its efficiency.
Poly(4-vinylpyridine) is reported as a green, commercial available and efficient basic recyclable catalyst for the synthesis of chromene derivatives. This catalyst can be easily recovered by simple filtration and recycled up to 5 consecutive runs without any loss of its efficiency.
2013, 24(3): 211-214
Abstract:
An efficient and eco-friendly method is reported for the synthesis of 2-substituted-2,3-dihydroquinazolin-4(1H)-ones from direct cyclocondensation of anthranilamide with aldehydes and ketones using N-propylsulfamic acid supported onto magnetic Fe3O4 nanoparticles (MNPs-PSA) as a recoverable and recyclable nanocatalyst in good to excellent yields in water at 70℃. The catalyst was readily separated using an external magnet and reusable without significant loss of their catalytic efficiency.
An efficient and eco-friendly method is reported for the synthesis of 2-substituted-2,3-dihydroquinazolin-4(1H)-ones from direct cyclocondensation of anthranilamide with aldehydes and ketones using N-propylsulfamic acid supported onto magnetic Fe3O4 nanoparticles (MNPs-PSA) as a recoverable and recyclable nanocatalyst in good to excellent yields in water at 70℃. The catalyst was readily separated using an external magnet and reusable without significant loss of their catalytic efficiency.
2013, 24(3): 215-218
Abstract:
The flavonoids as inhibitors of CYP1A1 exhibit chemopreventive effects against certain procarcinogens and have been considered as the promising cancer preventive agents. A series of novel 7,8-dimethoxy-α-naphthoflavones as the substrate analogs were designed and prepared. The enzyme assay suggested that all of these new flavones were stronger inhibitors of CYP1A1 than the lead compound a-naphthoflavone. Among the tested ones, 3h showed the most potent inhibitory effects.
The flavonoids as inhibitors of CYP1A1 exhibit chemopreventive effects against certain procarcinogens and have been considered as the promising cancer preventive agents. A series of novel 7,8-dimethoxy-α-naphthoflavones as the substrate analogs were designed and prepared. The enzyme assay suggested that all of these new flavones were stronger inhibitors of CYP1A1 than the lead compound a-naphthoflavone. Among the tested ones, 3h showed the most potent inhibitory effects.
2013, 24(3): 219-222
Abstract:
A series of 1-(benzylamino)-2-(2,4-difluorophenyl)-3-(1H-1,2,4-triazol-1-yl)propan-2-ols compounds were synthesized and evaluated for their antifungal activities in vitro. The results showed that compounds 6A and 6B exhibited good antifungal activity. Compound 6A8 showed the strongest antifungal activity, which was significantly higher than that of the lead compounds and positive-control drugs Fluconazole and Itraconazole. In particular, the antifungal activity of compound 6A8 against Candida albicans and Candida krusei (MIC80 both at 0.00097 mg/mL) was 515 and 64 times that of Fluconazole, respectively. The structure-activity relationships of the synthesized compounds were discussed, and the docking model of the target compounds with fungal lanosterol 14α-demethylase (CYP51) was analyzed.
A series of 1-(benzylamino)-2-(2,4-difluorophenyl)-3-(1H-1,2,4-triazol-1-yl)propan-2-ols compounds were synthesized and evaluated for their antifungal activities in vitro. The results showed that compounds 6A and 6B exhibited good antifungal activity. Compound 6A8 showed the strongest antifungal activity, which was significantly higher than that of the lead compounds and positive-control drugs Fluconazole and Itraconazole. In particular, the antifungal activity of compound 6A8 against Candida albicans and Candida krusei (MIC80 both at 0.00097 mg/mL) was 515 and 64 times that of Fluconazole, respectively. The structure-activity relationships of the synthesized compounds were discussed, and the docking model of the target compounds with fungal lanosterol 14α-demethylase (CYP51) was analyzed.
2013, 24(3): 223-226
Abstract:
Syntheses of two very important derivatives of quercetin, troxerutin and 3', 4', 7-triacetoxyethoxyquercetin were described. The latter was synthesized by highly selective esterification reaction in first time. The compounds were characterized by NMR, IR and Mass spectroscopy. Additionally, the antioxidant activities of the compounds were tested by means of improved pyrogallol autoxidation method. This was the first in using this method to test the antioxidant activities of these two compounds in vitro. The optimum system of pyorgallol autoxidation spectrophotometry was investigated and established according to the reaction rules. The assay indicated that these compounds showed noticeable antioxidant activities, and compound 2 was much more effective as a free radical scavenger than the compound 1 vitamin C was used as a reference material.
Syntheses of two very important derivatives of quercetin, troxerutin and 3', 4', 7-triacetoxyethoxyquercetin were described. The latter was synthesized by highly selective esterification reaction in first time. The compounds were characterized by NMR, IR and Mass spectroscopy. Additionally, the antioxidant activities of the compounds were tested by means of improved pyrogallol autoxidation method. This was the first in using this method to test the antioxidant activities of these two compounds in vitro. The optimum system of pyorgallol autoxidation spectrophotometry was investigated and established according to the reaction rules. The assay indicated that these compounds showed noticeable antioxidant activities, and compound 2 was much more effective as a free radical scavenger than the compound 1 vitamin C was used as a reference material.
2013, 24(3): 227-229
Abstract:
As a part of the ongoing studies in developing new antimicrobials, a series of structurally novel 3-bipyridinyl substituted coumarin derivatives 4a-f and 5a-f were synthesized by a single-step reaction protocol under Krohnke's reaction conditions. 1H NMR, 13C NMR, IR and mass spectral techniques were employed for the structural elucidation of the synthesized compounds. An evaluation of antimicrobial activity showed that almost all compounds exhibited better results than the referenced drugs. Among the synthesized derivatives 4f, 5a and 5d were found to be the most potent analogs. Thus they could be promising lead for novel drugs.
As a part of the ongoing studies in developing new antimicrobials, a series of structurally novel 3-bipyridinyl substituted coumarin derivatives 4a-f and 5a-f were synthesized by a single-step reaction protocol under Krohnke's reaction conditions. 1H NMR, 13C NMR, IR and mass spectral techniques were employed for the structural elucidation of the synthesized compounds. An evaluation of antimicrobial activity showed that almost all compounds exhibited better results than the referenced drugs. Among the synthesized derivatives 4f, 5a and 5d were found to be the most potent analogs. Thus they could be promising lead for novel drugs.
2013, 24(3): 230-232
Abstract:
A facile synthetic route of linezolid 1 has been developed. Using commercially available (R)-epichlorohydrin as the starting material, 1 was obtained through a sequence of cyclization, substitution, a Goldberg coupling, aminolysis and acetylation reactions. The synthetic route is easy to perform and can be scaled up.
A facile synthetic route of linezolid 1 has been developed. Using commercially available (R)-epichlorohydrin as the starting material, 1 was obtained through a sequence of cyclization, substitution, a Goldberg coupling, aminolysis and acetylation reactions. The synthetic route is easy to perform and can be scaled up.
2013, 24(3): 233-235
Abstract:
A series of new thiazoline derivatives 2-alkyl(aryl) imino-4-amino-5-ethoxycarbonyl-3-phenyl-3Hthiazoline (3) and bis(2-imino-4-amino-5-ethoxycarbonyl-3-phenyl-3H-thiazoline alkylene (4) have been synthesized by reactions of intermediate 4-amino-5-ethoxycarbonyl-2-methylthio-3-phenyl-3H-thiazolinium sulphate (2) with alkylamines or arylamine in 64%-89% yields. The structures of 3 and 4 have been confirmed by 1H NMR, EI-MS, IR spectroscopy and elemental analyses. Some compounds exhibited high or moderate herbicidal activities against the roots of rapeseed and barnyard grass at 100 mg/L.
A series of new thiazoline derivatives 2-alkyl(aryl) imino-4-amino-5-ethoxycarbonyl-3-phenyl-3Hthiazoline (3) and bis(2-imino-4-amino-5-ethoxycarbonyl-3-phenyl-3H-thiazoline alkylene (4) have been synthesized by reactions of intermediate 4-amino-5-ethoxycarbonyl-2-methylthio-3-phenyl-3H-thiazolinium sulphate (2) with alkylamines or arylamine in 64%-89% yields. The structures of 3 and 4 have been confirmed by 1H NMR, EI-MS, IR spectroscopy and elemental analyses. Some compounds exhibited high or moderate herbicidal activities against the roots of rapeseed and barnyard grass at 100 mg/L.
2013, 24(3): 236-238
Abstract:
One unusual dimeric tropane alkaloid, bishyoscyamine, was isolated from the roots of Anisodus acutangulus, whose structure including the absolute stereochemistry was unambiguously determined based on extensive 1D NMR and 2D NMR, HR-ESI-MS [α]D and CD spectroscopic analyses. To our knowledge, bishyoscyamine is the first example of tropane alkaloid dimer condensed by a C-N bond.
One unusual dimeric tropane alkaloid, bishyoscyamine, was isolated from the roots of Anisodus acutangulus, whose structure including the absolute stereochemistry was unambiguously determined based on extensive 1D NMR and 2D NMR, HR-ESI-MS [α]D and CD spectroscopic analyses. To our knowledge, bishyoscyamine is the first example of tropane alkaloid dimer condensed by a C-N bond.
2013, 24(3): 239-242
Abstract:
A "green" and quick analytical method for complex compounds was developed for simultaneous determination of tyrosine (Tyr) and dopamine (DA) in urine samples in this paper. The three-way responsive data recorded by excitation-emission matrix fluorescence (EEM) spectrometer was analyzed using second-order calibration methods based on both parallel factor analysis (PARAFAC) and selfweighted alternating trilinear decomposition (SWATLD) algorithms. The EEM spectra of the analytes were overlapped with the background in urine samples. However the second-order advantage of both PARAFAC and SWATLD methods was exploited, even in the presence of unknown interferences and the satisfactory results can be obtained. Furthermore, the linear ranges of Tyr and DA were determined to be 0.042-6.42 μg/mL and 0.18-4.43 μmg/mL, respectively, and the accuracies of both methods were validated by the analytical figures of merit (FOM).
A "green" and quick analytical method for complex compounds was developed for simultaneous determination of tyrosine (Tyr) and dopamine (DA) in urine samples in this paper. The three-way responsive data recorded by excitation-emission matrix fluorescence (EEM) spectrometer was analyzed using second-order calibration methods based on both parallel factor analysis (PARAFAC) and selfweighted alternating trilinear decomposition (SWATLD) algorithms. The EEM spectra of the analytes were overlapped with the background in urine samples. However the second-order advantage of both PARAFAC and SWATLD methods was exploited, even in the presence of unknown interferences and the satisfactory results can be obtained. Furthermore, the linear ranges of Tyr and DA were determined to be 0.042-6.42 μg/mL and 0.18-4.43 μmg/mL, respectively, and the accuracies of both methods were validated by the analytical figures of merit (FOM).
2013, 24(3): 243-245
Abstract:
A simple, fast, precise and eco-friendly method, based on ion chromatography (IC) with a suppressed conductivity detector, was proposed for the determination of benzoic acid (BA) inmilk in this paper. The chromatographic separation was accomplished by using an anion exchange column eluted with 3.2 μmol/L aqueous Na2CO3 and 1.0 mmol/L aqueous NaHCO3 at a flow-rate of 0.7 mL/min. Themethod validation experiment provided excellent results with respect to linearity (correlation coefficient up to 0.9997), limit of detection (0.1 μg/L), recovery values (ranging from 88.0% to 93.0%) and relative standard deviation (RSD) (below 2.2%, n = 7).
A simple, fast, precise and eco-friendly method, based on ion chromatography (IC) with a suppressed conductivity detector, was proposed for the determination of benzoic acid (BA) inmilk in this paper. The chromatographic separation was accomplished by using an anion exchange column eluted with 3.2 μmol/L aqueous Na2CO3 and 1.0 mmol/L aqueous NaHCO3 at a flow-rate of 0.7 mL/min. Themethod validation experiment provided excellent results with respect to linearity (correlation coefficient up to 0.9997), limit of detection (0.1 μg/L), recovery values (ranging from 88.0% to 93.0%) and relative standard deviation (RSD) (below 2.2%, n = 7).
2013, 24(3): 246-248
Abstract:
In this work, artificial neural network (ANN), a powerful chemometrics approach for linear and nonlinear calibration models, was applied to detect three pesticides in mixtures by linear sweep stripping voltammetry (LSSV) despite their overlapped voltammograms. Electrochemical parameters for the voltammetry, such as scan rate, deposit time and deposit potential, were evaluated and optimized from the signal response data using ANN model by minimizing the relative prediction error (RPE). The proposed method was successfully applied to the detection of pesticides in synthetic samples and several commercial fruit samples.
In this work, artificial neural network (ANN), a powerful chemometrics approach for linear and nonlinear calibration models, was applied to detect three pesticides in mixtures by linear sweep stripping voltammetry (LSSV) despite their overlapped voltammograms. Electrochemical parameters for the voltammetry, such as scan rate, deposit time and deposit potential, were evaluated and optimized from the signal response data using ANN model by minimizing the relative prediction error (RPE). The proposed method was successfully applied to the detection of pesticides in synthetic samples and several commercial fruit samples.
2013, 24(3): 249-252
Abstract:
In this work,magnesium tetraphenylporphyrin (MgTPP) was used as a new supramolecular amine-fixing agent. Once introduced, CO2 easily competes with MgTPP for amines, leading to the release of MgTPP. The processes can be explained by the fact that the association constant (Kassoc) values of MgTPP with amines were in the range of 0.6 (ethanolamine) to 3.9 (ethylenediamine), which are lower than the Kassoc values of CO2 with these amines. MgTPP interacted with aniline, ethanolamine, pyrrolidine, or ethylenediamine to form 1:1 adducts. Ethylenediamine presents a stronger Kassoc value for MgTPP, so it was considered an optimal agent for CO2 capture.
In this work,magnesium tetraphenylporphyrin (MgTPP) was used as a new supramolecular amine-fixing agent. Once introduced, CO2 easily competes with MgTPP for amines, leading to the release of MgTPP. The processes can be explained by the fact that the association constant (Kassoc) values of MgTPP with amines were in the range of 0.6 (ethanolamine) to 3.9 (ethylenediamine), which are lower than the Kassoc values of CO2 with these amines. MgTPP interacted with aniline, ethanolamine, pyrrolidine, or ethylenediamine to form 1:1 adducts. Ethylenediamine presents a stronger Kassoc value for MgTPP, so it was considered an optimal agent for CO2 capture.
2013, 24(3): 253-256
Abstract:
A new adsorbent, ammonium sulfamate-bacterial cellulose (ASBC), was prepared through chemical modifications of bacterial cellulose. The process of adsorbing Cr(Ⅵ) including its isotherm and kinetics, was measured and studied. The results showed that pH value was a very important parameter to the adsorbing efficiency. The adsorption kinetics can be described by a pseudo-second rate model and a particle diffusion equation. Both physical and chemical adsorptions existed in the adsorption process, but chemical adsorption was more dominatant. And particles internal diffusion was not the only rate controlling step. The adsorption equilibrium can be described by the Langmuir type, which indicated that a typical single-molecule layer adsorption of Cr(Ⅵ) by ASBC could be described. And the rate of adsorption followed the Slips model well, which indicated that ASBC had some multiphase and asymmetry. The coordination adsorption and ion exchange effect were the main mechanisms of chemical adsorption. The absorbed Cr(Ⅵ) can be desorbed effectively by 0.5 mol/L EDTA or HCl from the adsorbent, which could make it be reusable.
A new adsorbent, ammonium sulfamate-bacterial cellulose (ASBC), was prepared through chemical modifications of bacterial cellulose. The process of adsorbing Cr(Ⅵ) including its isotherm and kinetics, was measured and studied. The results showed that pH value was a very important parameter to the adsorbing efficiency. The adsorption kinetics can be described by a pseudo-second rate model and a particle diffusion equation. Both physical and chemical adsorptions existed in the adsorption process, but chemical adsorption was more dominatant. And particles internal diffusion was not the only rate controlling step. The adsorption equilibrium can be described by the Langmuir type, which indicated that a typical single-molecule layer adsorption of Cr(Ⅵ) by ASBC could be described. And the rate of adsorption followed the Slips model well, which indicated that ASBC had some multiphase and asymmetry. The coordination adsorption and ion exchange effect were the main mechanisms of chemical adsorption. The absorbed Cr(Ⅵ) can be desorbed effectively by 0.5 mol/L EDTA or HCl from the adsorbent, which could make it be reusable.
2013, 24(3): 257-259
Abstract:
Three tetraaryl imidazole derivatives 5a-5c bearing thiazole groups were synthesized in the presence of [Bmin]Br by one-pot reaction and their structures were fully characterized by the 1H NMR, IR, MS and elemental analysis. The results of UV-vis spectra and fluorescent spectra upon metal ions complexation show that compound 5a displays high selectivity and sensitivity for Cr3+ ions. The complexation ratio of compound 5a and Cr3+ is 1:1.
Three tetraaryl imidazole derivatives 5a-5c bearing thiazole groups were synthesized in the presence of [Bmin]Br by one-pot reaction and their structures were fully characterized by the 1H NMR, IR, MS and elemental analysis. The results of UV-vis spectra and fluorescent spectra upon metal ions complexation show that compound 5a displays high selectivity and sensitivity for Cr3+ ions. The complexation ratio of compound 5a and Cr3+ is 1:1.
2013, 24(3): 260-263
Abstract:
Anatase phase visible-light-driven TiO2 yolk-shell spheres with the size of ca. 1-2 μm have been synthesized with the combination of solvothermal and heat treatment method. XRD, SEM, TEM, XPS, and PL analysis were used to examine structure and properties of the photocatalyst. The N species and Ti3+ centers introduced into the as-prepared photocatalyst can enhance the visible light absorption significantly. The mesoporous shell of the prepared photocatalyst, which promotes the pollutant adsorption ability, consists of the high-reactive {0 0 1} facets dominated nanocrystals. Due to the unique structure, it is also observed that the as-prepared visible-light-driven TiO2 yolk-shell spheres exhibit a superior photocatalytic activity for organic dyes decomposition than the well-known P25.
Anatase phase visible-light-driven TiO2 yolk-shell spheres with the size of ca. 1-2 μm have been synthesized with the combination of solvothermal and heat treatment method. XRD, SEM, TEM, XPS, and PL analysis were used to examine structure and properties of the photocatalyst. The N species and Ti3+ centers introduced into the as-prepared photocatalyst can enhance the visible light absorption significantly. The mesoporous shell of the prepared photocatalyst, which promotes the pollutant adsorption ability, consists of the high-reactive {0 0 1} facets dominated nanocrystals. Due to the unique structure, it is also observed that the as-prepared visible-light-driven TiO2 yolk-shell spheres exhibit a superior photocatalytic activity for organic dyes decomposition than the well-known P25.
