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2018 Volume 81 Issue 8
2018, 81(8): 675-680
Abstract:
Surface molecular imprinting technology is a new type of molecular imprinting technology. It solves the problems of difficulty in incomplete template removal, low binding capacity, poor chromatographic performance and poor mechanical properties. Surface molecular imprinting polymers have attracted much attention due to their outstanding advantages, such as good chemical stability, high specificity and strong practicality. In recent years, it has been used widely in the separation and analysis of biochemical samples. This article describes the preparation of surface molecularly imprinted polymers, compares the advantages and disadvantages of different methods, and summarizes the application of surface molecular imprint in the separation and analysis.
Surface molecular imprinting technology is a new type of molecular imprinting technology. It solves the problems of difficulty in incomplete template removal, low binding capacity, poor chromatographic performance and poor mechanical properties. Surface molecular imprinting polymers have attracted much attention due to their outstanding advantages, such as good chemical stability, high specificity and strong practicality. In recent years, it has been used widely in the separation and analysis of biochemical samples. This article describes the preparation of surface molecularly imprinted polymers, compares the advantages and disadvantages of different methods, and summarizes the application of surface molecular imprint in the separation and analysis.
2018, 81(8): 681-691
Abstract:
Trivalent iodine reagents have similar reaction properties to transition metals such as mercury, titanium, and lead, and have the advantage of environment-friendly, low cost, mild reaction conditions, easy handling and commericial availaiblity. These compounds are widely used in organic synthesis, especially, as efficient selective oxidants that have attracted the attention of a large number of organic chemists. In this review, 14 kinds of oxidation reactions mediated by trivalent iodine reagents, including alcohol oxidation, oxidative functionalization of carbonyl compounds, to selenylation reactions and bismuthlation reactions etc., are briefly summarized.
Trivalent iodine reagents have similar reaction properties to transition metals such as mercury, titanium, and lead, and have the advantage of environment-friendly, low cost, mild reaction conditions, easy handling and commericial availaiblity. These compounds are widely used in organic synthesis, especially, as efficient selective oxidants that have attracted the attention of a large number of organic chemists. In this review, 14 kinds of oxidation reactions mediated by trivalent iodine reagents, including alcohol oxidation, oxidative functionalization of carbonyl compounds, to selenylation reactions and bismuthlation reactions etc., are briefly summarized.
2018, 81(8): 692-697
Abstract:
Side chain liquid crystalline polyether chelating resins have greater application performance than traditional polyether chelating resin owing to introduction of rigid mesogenic. They have become one of the hot spots in the field of resin in recent years with the advantages of good heat stability, adsorption capacity, ion selectivity, and easy design and syntheses. This paper introduces the syntheses, properties and application of side chain liquid crystalline polyether chelate resins. Finally, based on the requirements for the use of the mechanical properties, adsorption selectivity, regeneration performance, and environmental performance of the side chain liquid crystalline polyether chelate resins, the molecular design, synthetic methods and new application fields are prospected.
Side chain liquid crystalline polyether chelating resins have greater application performance than traditional polyether chelating resin owing to introduction of rigid mesogenic. They have become one of the hot spots in the field of resin in recent years with the advantages of good heat stability, adsorption capacity, ion selectivity, and easy design and syntheses. This paper introduces the syntheses, properties and application of side chain liquid crystalline polyether chelate resins. Finally, based on the requirements for the use of the mechanical properties, adsorption selectivity, regeneration performance, and environmental performance of the side chain liquid crystalline polyether chelate resins, the molecular design, synthetic methods and new application fields are prospected.
2018, 81(8): 698-704
Abstract:
The magnetic properties of dinuclear GdⅢNiⅡ complex[Ni(3-MeOsaltn)(MeOH) (ac)Gd(hfac)2]were studied using DFT-BS by several DFT methods and basis sets. These calculations have been performed by incorporating relativistic effects via the Douglas-Kroll-Hess method (level Ⅱ). The calculated magnetic coupling constants using the B3LYP showed an excellent agreement with the experimental parameters, and could accurately describe the magnetic properties of dinuclear GdⅢNiⅡ complexes. The analysis of magnetic orbitals and the spin density showed that the spin delocalization is from NiⅡ and spin polarization is from GdⅢ, magnetic orbitals principal constituents are 4fxyz and 4fz2x of Gd, 3dz2 and 3dx2-y2 of Ni and 2pz of the oxygen bridge (phenolato and acetato). With the increase of Gd-O-Ni bond angle, the square deviation of the paramagnetic center HS state and the BS state spin density and the contribution of antiferromagnetic interaction decrease, but the magnetic coupling constant of the complex increases.
The magnetic properties of dinuclear GdⅢNiⅡ complex[Ni(3-MeOsaltn)(MeOH) (ac)Gd(hfac)2]were studied using DFT-BS by several DFT methods and basis sets. These calculations have been performed by incorporating relativistic effects via the Douglas-Kroll-Hess method (level Ⅱ). The calculated magnetic coupling constants using the B3LYP showed an excellent agreement with the experimental parameters, and could accurately describe the magnetic properties of dinuclear GdⅢNiⅡ complexes. The analysis of magnetic orbitals and the spin density showed that the spin delocalization is from NiⅡ and spin polarization is from GdⅢ, magnetic orbitals principal constituents are 4fxyz and 4fz2x of Gd, 3dz2 and 3dx2-y2 of Ni and 2pz of the oxygen bridge (phenolato and acetato). With the increase of Gd-O-Ni bond angle, the square deviation of the paramagnetic center HS state and the BS state spin density and the contribution of antiferromagnetic interaction decrease, but the magnetic coupling constant of the complex increases.
2018, 81(8): 705-712
Abstract:
IRMOF-1 is one of the most classic IRMOF series MOFs materials. Three ZnO catalysts were prepared by heat treatment of IRMOF-1 directly in air at different temperatures, and the crystal structure, morphology, pore structure and surface alkalinity of the samples were characterized by XRD, SEM, BET measurements and CO2-TPD. The results showed that as-prepared ZnO are a typical mesoporous material with spherical structure, their BET surfcae area and pore size are 49.7~62.2 m2/g and 2.18~2.92 nm, respectively. The catalytic activities of mesoporous ZnO microspheres for the synthesis polycarbnate diol via diphenyl carbonate and neopentyl glycol (NPG) were investigated. The results exhibited that the ZnO microspheres obtained at 500℃ exhibit good catalytic activity in the transesterification of DPC and NPG.
IRMOF-1 is one of the most classic IRMOF series MOFs materials. Three ZnO catalysts were prepared by heat treatment of IRMOF-1 directly in air at different temperatures, and the crystal structure, morphology, pore structure and surface alkalinity of the samples were characterized by XRD, SEM, BET measurements and CO2-TPD. The results showed that as-prepared ZnO are a typical mesoporous material with spherical structure, their BET surfcae area and pore size are 49.7~62.2 m2/g and 2.18~2.92 nm, respectively. The catalytic activities of mesoporous ZnO microspheres for the synthesis polycarbnate diol via diphenyl carbonate and neopentyl glycol (NPG) were investigated. The results exhibited that the ZnO microspheres obtained at 500℃ exhibit good catalytic activity in the transesterification of DPC and NPG.
2018, 81(8): 713-719
Abstract:
The chemical components of chlorite are mainly SiO2、Fe2O3 and Al2O3, which are the main materials to prepare zeolite. Because of the higher Fe and Mg content of chlorite, in order to reduce the influence of impurities on the synthesis of zeolite, chlorite were activated with Na2CO3 by calcination, then silicon and aluminum ions in activated chlorite were leached by water and alkaline solution. ICP detection results showed that silicon and aluminum extraction rates of chlorite after pretreatment with Na2CO3 reach 71% and 67%, respectively. In addition, SEM, XRD, and FTIR analyses showed that the self-prepared Na-X zeolite has high purity, complete crystal form, good thermal stability, and uniform particle size (about 1~2μm). The as-prepared Na-X zeolite is a microporous adsorbent with average pore size range of 0.4~0.8 nm. In addition, the prepared Na-X zeolite meets the requirements of the Chinese chemical industry (HG/T2690-95) (water absorption rate is greater than 23%).
The chemical components of chlorite are mainly SiO2、Fe2O3 and Al2O3, which are the main materials to prepare zeolite. Because of the higher Fe and Mg content of chlorite, in order to reduce the influence of impurities on the synthesis of zeolite, chlorite were activated with Na2CO3 by calcination, then silicon and aluminum ions in activated chlorite were leached by water and alkaline solution. ICP detection results showed that silicon and aluminum extraction rates of chlorite after pretreatment with Na2CO3 reach 71% and 67%, respectively. In addition, SEM, XRD, and FTIR analyses showed that the self-prepared Na-X zeolite has high purity, complete crystal form, good thermal stability, and uniform particle size (about 1~2μm). The as-prepared Na-X zeolite is a microporous adsorbent with average pore size range of 0.4~0.8 nm. In addition, the prepared Na-X zeolite meets the requirements of the Chinese chemical industry (HG/T2690-95) (water absorption rate is greater than 23%).
2018, 81(8): 720-726
Abstract:
Using inexpensive and readily available hyodeoxycholic acid (HDCA) as the starting material and with the Shapiro reaction as a key step, ursodeoxycholic acid was successfully synthesized by a series of reactions including esterification, selective oxidation, epoxidation, and deprotection. The total yield was 25.8%. The whole procedure was further modified to make steps shorter through silyl protection, Rubottom oxidation and Clemmensen reduction, with an overall yield of 28.8%. The structures of all synthetic compounds were identified by 1H NMR, 13C NMR and HRMS. The aggregation behavior of similar bile acid salts with pyrene fluorescent probe was studied, the results showed that critical micelle concentration (CMC) value is only related to the number of hydroxyl group instead of configuration.
Using inexpensive and readily available hyodeoxycholic acid (HDCA) as the starting material and with the Shapiro reaction as a key step, ursodeoxycholic acid was successfully synthesized by a series of reactions including esterification, selective oxidation, epoxidation, and deprotection. The total yield was 25.8%. The whole procedure was further modified to make steps shorter through silyl protection, Rubottom oxidation and Clemmensen reduction, with an overall yield of 28.8%. The structures of all synthetic compounds were identified by 1H NMR, 13C NMR and HRMS. The aggregation behavior of similar bile acid salts with pyrene fluorescent probe was studied, the results showed that critical micelle concentration (CMC) value is only related to the number of hydroxyl group instead of configuration.
2018, 81(8): 727-733
Abstract:
In this paper, four kinds of C2 axis chiral biaryl organic catalysts were successfully synthesized and used to catalyze the reaction of tetrahydrothiopyran-4-one and aromatic aldehydes. It is demonstrated that using dichloromethane as solvent, the molar ratio of aromatic aldehyde and tetrahydrothiopyran-4-one is 1.2:5, the dosage of catalyst is 10(mol)%, the temperature and time of reaction are 0℃ and 20 h, the target products can be obtained with higher yield (up to 85%) and better stereoselectivity (up to 86%).
In this paper, four kinds of C2 axis chiral biaryl organic catalysts were successfully synthesized and used to catalyze the reaction of tetrahydrothiopyran-4-one and aromatic aldehydes. It is demonstrated that using dichloromethane as solvent, the molar ratio of aromatic aldehyde and tetrahydrothiopyran-4-one is 1.2:5, the dosage of catalyst is 10(mol)%, the temperature and time of reaction are 0℃ and 20 h, the target products can be obtained with higher yield (up to 85%) and better stereoselectivity (up to 86%).
2018, 81(8): 734-738
Abstract:
The imidazolium group is an attractive building block for anion receptors because in contributes a positive charge and relatively acidic C2-hydrogen. By the use of tetra(1-imidazolylmethyl) methane 1, we designed a series of novel imidazoliums with alkylating reagents, including imidazolium 2, the open chain bis-imidazolium salt 3, imidazolium cyclophane 4. The spectral response of compound 2, 3, 4 to anion was further determined by fluorescence spectra. The results showed that imidazolium 2 and imidazolium cyclophane 4a have a better selectivity for Cl-, bisimidazolium 3a has definite recognition ability to PhCOO-, bisimidazolium 3b and imidazolium cyclophane 4b have a better selectivity for I-.
The imidazolium group is an attractive building block for anion receptors because in contributes a positive charge and relatively acidic C2-hydrogen. By the use of tetra(1-imidazolylmethyl) methane 1, we designed a series of novel imidazoliums with alkylating reagents, including imidazolium 2, the open chain bis-imidazolium salt 3, imidazolium cyclophane 4. The spectral response of compound 2, 3, 4 to anion was further determined by fluorescence spectra. The results showed that imidazolium 2 and imidazolium cyclophane 4a have a better selectivity for Cl-, bisimidazolium 3a has definite recognition ability to PhCOO-, bisimidazolium 3b and imidazolium cyclophane 4b have a better selectivity for I-.
2018, 81(8): 739-744
Abstract:
Two novel chalcone derivatives with ferrocenyl, 1-ferrocenyl-3-(4-tert-butylphenyl) acrylic ketone (a) and 1-ferrocenyl-3-biphenylyl acrylic ketone (b) were synthesized and characterized by 1H NMR, 13C NMR and HR-MS. The thermodynamic properties of compounds a and b were measured. Their molecular orbital energies and polarizabilities were calculated by quantum chemical method, and then the electronic cloud figures of these orbitals were obtained. Their linear and nonlinear optical properties were investigated using UV-Vis absorption spectra and Z-scan technique, respectively. The results indicated that the absorption of compounds a and b increases significantly, and the absorption wavelength of compound b is longer. Both compounds a and b have intramolecular charge transfer phenomena, exhibiting ultrafast third-order nonlinear optical response.
Two novel chalcone derivatives with ferrocenyl, 1-ferrocenyl-3-(4-tert-butylphenyl) acrylic ketone (a) and 1-ferrocenyl-3-biphenylyl acrylic ketone (b) were synthesized and characterized by 1H NMR, 13C NMR and HR-MS. The thermodynamic properties of compounds a and b were measured. Their molecular orbital energies and polarizabilities were calculated by quantum chemical method, and then the electronic cloud figures of these orbitals were obtained. Their linear and nonlinear optical properties were investigated using UV-Vis absorption spectra and Z-scan technique, respectively. The results indicated that the absorption of compounds a and b increases significantly, and the absorption wavelength of compound b is longer. Both compounds a and b have intramolecular charge transfer phenomena, exhibiting ultrafast third-order nonlinear optical response.
2018, 81(8): 745-752
Abstract:
β-secretase (BACE1) is a potent target for Alzheimer's disease (AD). Inhibition of BACE1 has gained considerable attention as a potential disease-modifying treatment of AD. In this study, 66 aminooxazoline xanthene-based BACE1 inhibitors were simulated by comparative molecular similarity index (CoMSIA) and molecular docking methods. A reliable prediction model of structure-activity relationship (Q2=0.86, Rncv2=0.97, Rpre2=0.88) was constructed, revealing the important structural features information that influences the inhibitory activity of the molecules. Moreover, it was found that the inhibitor occupies S3, S1 and S2' active sites of target through hydrogen bonding and π-π stacking interactions formed with BACE1. The model and information deduced from this in silico analysis provide important theoretical guidance for the structural optimization and modification of new and efficient BACE1 inhibitors.
β-secretase (BACE1) is a potent target for Alzheimer's disease (AD). Inhibition of BACE1 has gained considerable attention as a potential disease-modifying treatment of AD. In this study, 66 aminooxazoline xanthene-based BACE1 inhibitors were simulated by comparative molecular similarity index (CoMSIA) and molecular docking methods. A reliable prediction model of structure-activity relationship (Q2=0.86, Rncv2=0.97, Rpre2=0.88) was constructed, revealing the important structural features information that influences the inhibitory activity of the molecules. Moreover, it was found that the inhibitor occupies S3, S1 and S2' active sites of target through hydrogen bonding and π-π stacking interactions formed with BACE1. The model and information deduced from this in silico analysis provide important theoretical guidance for the structural optimization and modification of new and efficient BACE1 inhibitors.
2018, 81(8): 753-758
Abstract:
Conductivity and rheological properties of aggregated behaviors of sodium bis(2-ethylhexyl) sulfosuccinate (AOT) in polyethylene glycol 200 (PEG 200) and water mixed solvent media were studied as a function of temperature and AOT concentration. The results showed that the system appears network structure of gel at higher AOT concentration and at room temperature. For the system of AOT concentration over 400mmol/kg, the solution is colorless, transparent and syrupy with no polarized behavior at low temperature, showing the formation of gel. Then the solution changes a little turbid accompanied by the rapid increase of conductivity with increasing the temperature, indicating the appearance of vesicles. As the temperature continues to rise, the solution becomes transparent again. So, the AOT solution changes from gel to vesicles, and finally micelles as the temperature increases, and the process is reversible. While for the system of AOT concentration between 200 and 400 mmol/kg, the solution transforms from the coexisting system of gel-micelles to pure micelles system.
Conductivity and rheological properties of aggregated behaviors of sodium bis(2-ethylhexyl) sulfosuccinate (AOT) in polyethylene glycol 200 (PEG 200) and water mixed solvent media were studied as a function of temperature and AOT concentration. The results showed that the system appears network structure of gel at higher AOT concentration and at room temperature. For the system of AOT concentration over 400mmol/kg, the solution is colorless, transparent and syrupy with no polarized behavior at low temperature, showing the formation of gel. Then the solution changes a little turbid accompanied by the rapid increase of conductivity with increasing the temperature, indicating the appearance of vesicles. As the temperature continues to rise, the solution becomes transparent again. So, the AOT solution changes from gel to vesicles, and finally micelles as the temperature increases, and the process is reversible. While for the system of AOT concentration between 200 and 400 mmol/kg, the solution transforms from the coexisting system of gel-micelles to pure micelles system.
2018, 81(8): 759-762
Abstract:
A series of 2, 3-diphenyl-4-thiazolidinone derivatives were synthesized and characterized by 1H NMR and MS. Their antifungal activities were also evaluated in vitro at the concentration of 100 μg/mL against seven phytopathogenic fungi, namely F. graminearum, A. alternata, F.oxysporium f. sp. vasinfectum, P.oryzae, V.mali, A.solani and A.brassicae. Among all compounds, 4g exhibits a potential antifungal activity against V. mali with the highest inhibition rates of 62.7%. Introduction of the methyl group at the phenyl ring of 4-thiazolidinone derivatives could generally increase the potency.
A series of 2, 3-diphenyl-4-thiazolidinone derivatives were synthesized and characterized by 1H NMR and MS. Their antifungal activities were also evaluated in vitro at the concentration of 100 μg/mL against seven phytopathogenic fungi, namely F. graminearum, A. alternata, F.oxysporium f. sp. vasinfectum, P.oryzae, V.mali, A.solani and A.brassicae. Among all compounds, 4g exhibits a potential antifungal activity against V. mali with the highest inhibition rates of 62.7%. Introduction of the methyl group at the phenyl ring of 4-thiazolidinone derivatives could generally increase the potency.
2018, 81(8): 763-767
Abstract:
Combining the characteristics of agricultural university and the specialty of applied chemistry, and in order to convert the scientific research achievements into the experimental teaching contents, an innovative chemical experiment of "rapidly preparation of fluorescent carbon dots by green hydrothermal method" was designed. The preparation methods and characterization techniques of the hydrothermal method and carbon dots were well annotated in the project. On the other hand, the structure, working principle and operation skills of large-scale scientific instruments such as transmission electron microscope and fluorescence spectrometer were elaborated. Moreover, experimental teaching closely integrates with scientific research, it can not only stimulate students' inquiry psychology and study interests, broaden their horizons, but also cultivate students' innovative practical capabilities and scientific thinking. With the improvement of students' competence in solving problems, they will open a new path to modified teaching mode of the research innovative chemistry experiment in agricultural universities.
Combining the characteristics of agricultural university and the specialty of applied chemistry, and in order to convert the scientific research achievements into the experimental teaching contents, an innovative chemical experiment of "rapidly preparation of fluorescent carbon dots by green hydrothermal method" was designed. The preparation methods and characterization techniques of the hydrothermal method and carbon dots were well annotated in the project. On the other hand, the structure, working principle and operation skills of large-scale scientific instruments such as transmission electron microscope and fluorescence spectrometer were elaborated. Moreover, experimental teaching closely integrates with scientific research, it can not only stimulate students' inquiry psychology and study interests, broaden their horizons, but also cultivate students' innovative practical capabilities and scientific thinking. With the improvement of students' competence in solving problems, they will open a new path to modified teaching mode of the research innovative chemistry experiment in agricultural universities.
