bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis and Structure of Tetraploid (Imidazole) Copper (II) Terephthalate, [Cu(Im)4] (teph)
Authors: Wan Jun , Ye Su‐Juan , Wen Yong‐Hong , Zhang Shu‐Sheng
Published: September 2010

The crystal structure of [Cu (Im)4] (teph) (Im = imidazole, teph = terephthalate) has been determined by X‐ray crystallography. It crystallizes in the triclinic system, space group Pī with cell dimensions of a = 0.80356 (16) nm, b = 0.84269 (17) run, c = 0.88967 (18) nm, α = 76.90 (3)°, β = 68.95 (3)°, γ = 75.94 (3)°, and Z = 1. Its structure of the title compound is composed of discrete monomelic molecule of [Cu (Im)4]‐(teph). The copper (II) ions have a square plane geometry with the CuN4 chromophore.
Kinetics and Mechanism of Oxidation of Ethylene Glycol Monoethylether by Diperiodatonickelate(IV) in Alkaline Medium
Authors: Shan Jin‐Huan , Wei Hai‐Ying , Shen Shi‐Gang , Sun Han‐Wen
Published: September 2010

The kinetics of oxidation of ethylene glycol monoethylether (EGE) by diperiodatonickelate(IV) ion (DPN) was studied by spectrophotometry in alkaline medium. The reaction rate showed first order dependence on Ni(IV) and positive fractional order with respect to EGE. The pseudo‐first order rate constants, kobs increased with the increase of [OH−] and decreased with the increase of [IO4−]. Added salts had little effect on the rate and no free radical was detected. Based on these, the mechanism including the equilibrium between DPN and EGE was proposed. Furthermore, the activation parameters of the reaction were calculated.
Synthesis, Crystal Structure, UV‐vis and EPR Studies of (NH3CH2CH2NH2)2.5[Mo(V)0.5W(VI)0.5O2(OC6H4O)2]
Authors: Lu Xiao‐Ming , Song Fu‐Gen , Lou Fu‐Yan , Mao Xi‐An , Ye Zhao‐Hui , Lu Jing‐Fen
Published: September 2010

Cis‐dioxo‐metal complex (NH3CH2CH2NH2)2.5[Mo(V)0.5W(VI)0.5O2‐(OC6H4O)2] 1 was obtained by the reaction of tetra‐butyl ammonium hexamolybdotungstate with 1, 2‐dihydroxybenzene in the mixed solvent of CH3OH, CH3CN and ethylenediamine, and characterized by X‐ray diffraction, UV‐vis and EPR analysis. Compared with its analogous complexes (NH3CH2CH2‐NH2)3[Mo(V)O2(OC6H4O)2] 2 and (NH3CH2CH2NH2)2[W(VI)‐O2(OC6H4O)2] 3, the results show that tungsten(VI) is less active in redox than molybdenum (VI) and that the change of the valence induced by substitution of W(VI) for Mo(V) in [MO2‐(OC6H4O2]n‐does not influence the coordination geometry of the complex anion in which the metal center exhibits distorted octahedral coordination withcis‐dioxo catechol. The responses to EPR of complexes 1 and 2 are active but complex 3 is silent, and the UV‐vis spectra exhibited by the three complexes are obvious different because of the different electronic configuration between the central Mo(V) and W(VI) ions in the complexes. It is noteworthy that complexes 1 and 2 have the similar EPR signal to flavoenzyme, suggesting that the three complexes have the same coordination geometry feature with the co‐factor of flavoenzyme.
Investigation of Mixed Chiral Selectors of Different Metal Ion‐L‐Alanine Complex and β‐Cyclodextrin on the Chiral Separation of Dansyl Amino Acids with Capillary Electrophoresis
Authors: Zheng Zhi‐Xia , Qu Feng , Lin Jin‐Ming
Published: September 2010

Chiral separation of dansyl amino acids by capillary electrophoresis using mixed selectors of Mn (II)‐L‐alanine complex and β‐cyclodextrin (β‐CD) was studied. Resolution was considerably superior to that obtained by using either Mn(II)‐L‐alanine complex or β‐CD alone. The effects of separation parameters, such as pH value of buffer solution, capillary temperature, the concentration of Mn (II)‐L‐alanine complex, the types of CD and ligand on the migration times and resolutions were investigated. Six different transition metal complexes, Cu(II), Zn(II), Co(II), Ni(II), Hg(n) and Cd(n)‐L‐alanine complexes have been employed and compared with Mn(II) complex. Differences in retention and selectivity were found. The substitution of Cu(II), Zn(H), Co(II) and Ni(II) for Mn (II) resulted in a better chiral resolution while Hg(II) and Cd (II) showed poorer resolution abilities. The chiral separation mechanism was also discussed briefly.
Fluorescence Quenching and Binding Interaction of 10‐Methylacridinium Iodide to Nucleic Acids
Authors: Sun Xian‐Feng , Jiang Zhi‐Qin , Ding Bing‐Lin
Published: September 2010

Interaction of 10‐methylacridinium iodide (MAI) as fluorescence probe with nucleobases, nucleosides and nucleic acids has been studied by UV‐visible absorption and fluorescence spectroscopy. It was found that fluorescence of MAI is strongly quenched by the nucleobases, nucleosides and nucleic acids, respectively. The quenching follows the Stern‐Volmer linear equation. The fluorescence quenching rate constant (kq) was measured to be 109‐1010 (L/mol)/s within the range of diffusion‐controlled rate limit, indicating that the interaction between MAI and nucleic acid and their precursors is characteristic of electron transfer mechanism. In addition, the binding interaction model of MAI to calf thymus DNA (ct‐DNA) was further investigated. Apparent hypochromism in the absorption spectra of MAI was observed when MAI binds to ct‐DNA. Three spectroscopic methods, which include (1) UV spectroscopy, (2) fluorescence quenching of MAI, (3) competitive dual‐probe method of MAI and ethidium bromide (EB), were utilized to determine the affinity binding constants (K) of MAI and ct‐DNA. The binding constants K obtained from the above methods gave consistent data in the same range (1.0–5.5) × 104L/mol, which lend credibility to these measurements. The binding site number was determined to be 1.9. The influence of thermal denaturation and phosphate concentration on the binding was examined. The binding model of MAI to ct‐DNA including intercalation and outside binding was investigated.
(E)‐α‐Bromovinylselenides as Convenient Precursors for Stereoselective Synthesis of Trisubstituted Alkenes
Authors: Cai Ming‐Zhong , Huang Jia‐Di , Hao Wen‐Yan
Published: September 2010

Based on the different reactivity of selanyl and bromo groups, (E)‐α‐bromovinylselenides can undergo sequential cross coupling reactions with nucleophiles in the presence of transition metal complexes to form two carbon‐carbon bonds in the same olefinic carbon leading to trisubstituted alkenes stereoselectively in good yields.
Novel Synthesis of N‐Substituted p‐Hydroxybenzoic Amides on Soluble Polymer‐Support
Authors: Hu Chun‐Ling , Chen Zu‐Xing , Yang Gui‐Chun
Published: September 2010

The synthesis of N‐substituted p‐hydroxybenzoic amides using a liquid phase approach is described. Poly (ethylene glycol) (PEG) and p‐hydroxybenzoic acid were linked by oxalyl chloride to give compound 1, which was chlorinated by thionyl chloride, followed by amidation with NHR1R2 to yield compound 3. Hydrolysis of compound 3 gave the title amide 4. These crude library members were obtained in good yields with high purities.
Solid Phase Synthesis of Ethyl β‐Substituted Indolepropionates
Authors: Liu Zhan‐Xiang , Ruan Xiu‐Xiu , Huang Xian
Published: September 2010

A facile solid phase synthesis of ethyl β‐substituted indolepropionates is reported. Condensation between indole, polymer‐supported cyclic malonic acid ester and aldehyde yielded the trimolecular adducts, which was cleaved by pyridine/EtOH to release the final products in good yield with high purity.
Triterpenoid Saponins from Luculia pincia Hook
Authors: Kang Wen‐Yi , Wang Jun‐Song , Yang Xiao‐Sheng , Hao Xiao‐Jiang
Published: September 2010

Two new triterpenoid saponins, cincholic acid‐3‐O‐β‐D‐xylopyranoside, 28‐O‐β‐D‐glucopyranosyl ester (1), quinovic acid‐28‐O‐β‐D‐glucopyranosyl ester (4), and a new phenolic glucoside, 4‐[4'‐O‐(2', 3', 5', 6'‐tetrahydroxy phenyl)‐β‐D‐glucoside]‐1‐butene (2), along with five known triterpenoid saponins and one phenolic glucoside were isolated from the n‐butanol fraction of the stems of Luculia pinciana Hook. Their structures were established by means of spectroscopic methods.
Asymmetric Arrangement of Monolayer in the Multilayer Films of 2‐Hydroxy‐4,4'‐dihexyloxy‐azobenzene
Authors: Jin Jian , Wang Gang , Yang Wen‐Sheng , Liu Guo‐Zong , Li Tie‐Jin
Published: September 2010

Multilayer films of 2‐hydroxy‐4,4'‐dihexyloxy‐azobenzene (HAB) on silicon substrates have been studied with atomic force microscopy, temperature‐dependent FTIR, and X‐Ray diffraction technique. The results show that the multilayer films are formed by stacking of HAB monolayers via π‐π interactions and the adjacent two monolayers in the film are arranged in an asymmetric way in the multilayer films.
o‐ZrW1.6Mo0.4O8: A Novel Orthorhombic Intermediate Phase Formed During the Synthesis of the Negative Thermal Expansion Cubic ZrW1.6Mo0.4O8 Material by the Precursor Dehydration Route
Authors: Zhao Xin‐Hua , Huang Ling , Liu Peng‐Hui , Ma Hui
Published: September 2010

The mechanism of the precursor dehydration route was revealed for the synthesis of NTE c‐ZrW1.6Mo0.4O8. The hydrate precursor was dehydrated at 473 K and transformed to a NTE cubic compound above 800 K. A novel intermediate phase o‐ZrW1.6Mo0.4O8 occurs between the temperature range of 573–800 K. The XRD pattern of novel intermediate was refined with the structural model of LT‐ZrMo2O8 by using Rietveld method. The residuals are Rwp = 7.80% and Rp = 5.79%. The space group is Pmn21 and the lattice parameters are a = 0.5917(4) nm, b =0.7273(4) nm, c =0.9148(6) nm, and Z = 2.
Studies on Tripolycyanamide Formaldehyde Resin‐Pd Complex and Its Use in the Synthesis of the Branch of Paclitaxel
Authors: Qi Chuan‐Min , Yang Ling‐Chun , Wang Li‐Yuan
Published: September 2010

A novel method was developed to prepare the branch of paclitaxel using 2, 4‐dichlorophenylaldehyde as the starting material. The branch was synthesized through condensation, cycloaddition and catalyzing hydrogenation of dichlorophenyl intermediate. Tripolycyanamide formaldehyde resin‐Pd complex as hydrogenation catalyst has been studied. The influence of temperature and N/Pd atomic ratio of the catalyst on the effect of catalytic hydrogenation was investigated and the optimum conditions were found. Because of the mild cyclization reaction condition, convenient asymmetric resolution operation and high yield, the synthetic route was practical.
Non‐isothermal Kinetics of the Thermal Decomposition of 3‐Nitro‐1, 2, 4‐triazol‐5‐one Magnesium Complex
Authors: Ma Hai‐Xia , Song Ji‐Rong , Hu Rong‐Zu , Li Jun
Published: September 2010

The thermal decomposition of 3‐nitro‐1, 2, 4‐triazol‐5‐one magnesium complex and its kinetics were studied under the non‐isothermal condition by DSC and TG/DTG methods. The kinetic parameters were obtained from analysis of the DSC and TG/DTG curves by the Kissinger method, the Ozawa method, the differential method and the integral method. The most probable mechanism functions for the thermal decomposition of the first stage, the second stage and the third stage were suggested by comparing the kinetic parameters. The entropy of activation (ΔS−), enthalpy of activation (ΔH−) and free energy of activation (AC) at Tpdo are‐66.74 J‐mol−1K−1, 119.2 kJ‐moI−1 and 152.44 kJ · mol−1, respectively.
Synthesis, Characterization and Thermochemistry of 2MgO · B2O3 · 1.5H2O
Authors: Liu Zhi‐Hong , Zhao U , Hu Man‐Cheng
Published: September 2010

A new magnesium borate 2MgO‐B2O3‐1.5H2O has been synthesized by the method of phase transformation of double salt under hydrothermal condition and characterized by XRD, IR, Raman spectra and TG. The enthalpy of solution of 2MgO · B2O3 · 1.5H2O in 2.9842 mol‐L−1 HCl was determined. From a combination of this result with measured enthalpies of solution of H3BO3 in 2.9842 mol · L−1 HCl(aq.) and of MgO in (HCl + H3BO3) solution, together with the standard molar enthalpies of formation of MgO(s), H3BO3(s), and H2O(1), the standard molar enthalpy of formation of‐(3019.76 ± 1.79) kJ · mol−1 of 2MgO · B2O3 · 1. 5H2O was obtained. 2MgO · B2O3 · 1.5H2O, synthesis, characterization, standard molar enthalpy of formation
Standard Molar Enthalpies of Formation of Ce(TCA)3 · 3H2O(s) and Ce(TCA)(C9H6NO)2(s)
Authors: Li Qiang‐Guo , Ye Li‐Juan , Shou Meng‐Juan
Published: September 2010

The standard molar reaction enthalpies of two reactions, CeCl3 · 7H2O(s) + 3CCl3COOH(s) = Ce(TCA)3· 3H2O(s) +3HCl(g) + 4H2O(1) (1) and Ce(TCA)3· 3H2O (s) + 2C9H7NO (S) = Ce(TCA) (C9H6NO)2 (s) + 2CCl3COOH(s) + 3H2O(1) (2), were investigated by classical solution calorimetry and an isoperibol calorimeter at 298.15 K. The standard molar enthalpies ΔsH·m of solution of CeCl3 · 7H2O(s), 3CCl3COOH(s), Ce(TCA)3 · 3H2O(s), Ce(TCA)3 · 3H2O(s), 2C9H7NO(s), Ce‐(TCA) (C9H6NO)2(s) and 2CCl3COOH(s) were determined to be (50.615 ± 0.028), (23.431 ± 0.027), (94.206 ± 0.010), (54.151 ± 0.020), (27.485 ± 0.045), (106.392 ± 0.060) and‐(14.893 ± 0.026) kJ/mol, respectively. The reaction enthalpies ΔrH⊖m of reactions (1) and (2) were obtained to be (204.279 ± 0.023) and‐(9.863 ± 0.041) kJ/mol, respectively. According to the above results and the data given in literature, through Hess' law, the standard molar enthalpies ΔtH⊖m of formation of Ce(TCA)3 ± 3H2O(s) and Ce(TCA)(C9H6NO)2 (s) were estimated to be‐(3060.0 ± 0.087) and‐(1369.0 ± 0.292) kJ/mol, respectively.
Synthesis, Structure and Adsorption of AIPO‐21 Prepared by Cotemplate Method
Authors: Zhang Lei , Cheng Xiao‐Wei , Long Ying‐Cai
Published: September 2010

The phase of AIPO‐21 was hydrothermally synthesized in the reactant system of diethylamine‐RB‐Al2O3‐O5‐H2O‐C2H5OH. The crystals of AIPO‐21 growing in this system crystallizes in monoclinic system, space group P21/n with a = 0.8542(4) nm, b = 1.7635(8) nm, c = 0.9082(4) nm, β = 108.234(5)°, V = 1.2993(10) nm3, Z = 4, and the formula is [C4H10 NH2]+ = [Al3P3O12 (OH)]−. The structure is resolved by the direct method and refined to R1 = 0.0767 and wR2 = 0.1627 based on 1719 observed reflections with I > 2.0σ (I). An asymmetric unit consists of three PO4 tetrahedra, one AIO4 tetrahedron and two AIO5 trigonal bipyramids. The framework is composed of 3‐D uniform channels along [100], [001] and [101] with eight‐membered oxygen ring windows. The powder sample of the MS was investigated with powder XRD, TG/DTG/DTA and the adsorption of water, methanol, n‐hexane, ethylene, and ethane. The specific property for sieving molecules was observed on the adsorption isotherms, and proves the result of the single crystal structural analysis.
High Selective Determination of Anionic Surfactant Using Its Parallel Catalytic Hydrogen Wave
Authors: Guo We , He Ying‐Ying , Song Jun‐Feng
Published: September 2010

A faradaic response of anionic surfactants (AS), such as linear alkylbenzene sulfonate (LAS), dodecyl benzene sulfonate and dodecyl sulfate, was observed in weak acidic medium. The faradaic response of AS includes (1) a catalytic hydrogen wave of AS in HAc/NaAc buffer that was attributed to the reduction of proton associated with the sulfo‐group of AS, and (2) a parallel catalytic hydrogen wave of AS in the presence of hydrogen peroxide, which was due to the catalysis of the catalytic hydrogen wave of AS by hydroxyl radical OH electrogenerated in the reduction of hydrogen peroxide. The parallel catalytic hydrogen wave is about 50 times as sensitive as the catalytic hydrogen wave. Based on the parallel catalytic hydrogen wave, a high selective method for the determination of AS was developed. In 0.1 mol/L HAc/NaAc (pH = 6.2 ± 0.1)/1.0 ± 10−3 mol/L H2O2 supporting electrolyte, the second‐order derivative peak current of the parallel catalytic hydrogen wave located at‐1. 33 V (vs. SCE) was rectilinear to AS concentration in the range or 3.0 × 10–6‐2.5 × 10–4 mol/L, without the interference of other surfactants. The proposed method was evaluated by quantitative analysis of AS in environmental waste water.
Synthesis of Unsymmetrical Branched Polyether Dendrons from 3, 4‐Methylene‐dioxybenzaldehyde
Authors: Zhou Zhao‐Li , Wang Feng , Cao Xiao‐Ping
Published: September 2010

Unsymmetrical dendrons 1, 2 and 3 were easily prepared according to a novel convergent strategy from 3, 4‐methylene‐dioxybenzaldebyde as starting material.
Ligand Exchange Between Penta‐Coordinated Phosphoryl Serine and Histidine Compounds
Authors: Cao Shu‐Xia , Niu Ming‐Yu , Su Yu‐Qian , Liao Xin‐Cheng , Lu Kui , Zhao Yu‐Fen
Published: September 2010

With the assistance of HPLC‐ESI‐MS/MS, the self‐assembly products of serine and histidine penta‐coordinated phosphorus compound were separated and identified. The expectative product was seryl‐histidine dipeptide, but it was found that there was almost equimolar amount of histidyl‐histidine dipeptide as well as seryl‐histidine dipeptide. The mechanism was speculated that there was ligand exchange between penta‐coordinated phosphoryl serine and histidine in the reaction process. As a result, two types of dipeptide were produced.
Structure of an Extracellular Polysaccharide from a Strain of Lactic Acid Bacteria
Authors: Gu Xiao‐Mei , Ma Gui‐Rong , Wu Hou‐Min
Published: September 2010

A new extracellular polysaccharide (EPS‐I) isolated and purified from Z222, a strain of Lactic acid bacteria has been investigated. Sugar composition analysis, methylation analysis and 1H NMR and 13C NMR spectroscopy reveal that the EPS‐I is composed of a pentasaccharide repeating unit. The sequence of sugar residue was determined by using two‐dimensional NMR spectroscopy, including heteronuclear multiple‐bond correlation (HMBC) and nuclear overhauser effect spectroscopy (NOESY).
Theoretical Elucidation on Different Lipid‐Oxidation Potentials of Aminoxyl Antioxidants
Authors: Wang Lan‐Fen , Zhang Hong‐Yu
Published: September 2010

To elucidate the different lipid‐oxidation potentials of aminoxyl antioxidants, a kind of combined density functional theory (DFT) method was employed to calculate CH bond dissociation enthalpies (BDEs) of a model linoleic acid (LH) and OH BDEs of hydrogenated aminoxyls. The higher the OH BDE is, the more potent the aminoxyl to abstract the H‐atom from LH and the stronger the LH‐oxidation potential. Accordingly, the prooxidant activity differences of aminoxyls were elucidated by the different OH BDEs of hydrogenated aminoxyls, which were further clarified in terms of distinct electronic effects of the substituents.
Thermodynamic Investigation of the Azeotropic Mixture Composed of Water and Benzene
Authors: Nan Zhao‐Dong , Tan Zhi‐Cheng
Published: September 2010

The molar heat capacity of the azeotropic mixture composed of water and benzene was measured by an adiabatic calorimeter in the temperature range from 80 to 320 K. The phase transitions took place in the temperature range from 265.409 to 275.165 K and 275.165 to 279.399 K. The phase transition temperatures were determined to be 272.945 and 278.339 K, which were corresponding to the solid‐liquid phase transitions of water and benzene, respectively. The thermodynamic functions and the excess thermodynamic functions of the mixture relative to standard temperature 298.15 K were derived from the relationships of the thermodynamic functions and the function of the measured heat capacity with respect to temperature.
Tailor and Control of Acidic Strength in Ordered Mesoporous Aluminosilicates by Using Preformed Zeolite Precursors
Authors: Lin Sen , Wang Li‐Feng , Han Yu , Yu Yi , Di Yan , Wang Run‐Wei , Jiang Da‐Zhen , Xiao Feng‐Shod
Published: September 2010

The acidic strength of ordered mesoporous aluminosilicates of MAS‐2, MAS‐3, MAS‐7 and MAS‐9 and microporous crystals of Y. L, beta, and ZSM‐5 zeolites was systemically investigated by temperature‐programmed desorption of ammonia (NH3‐TPD). Due to the use of preformed zeolite precursors of Y. L, beta and ZSM‐5, the ordered mesoporous aluminosilicates with distinguished acidic strength were obtained. being dependent on the type of preformed zeolite precursors. Therefore, the acidic strength of these mesoporous aluminosilicates could be tailored and controlled.
Kinetics of the First Order Autocatalytic Decomposition Reaction of Nitrocellulose (13.86% N)
Authors: Guo Peng‐Jiang , Hu Rong‐Zu , Ning Bin‐Ke , Yang Zheng‐Quan , Song Ji‐Rong , Shi Qi‐Zhen , Lu Gui‐E , Jiang Jin‐You
Published: September 2010

The kinetics of the first order autocatalytic decomposition reaction of nitrocellulose (NC, 13.86% N) was studied by using DSC. The results show that the DSC curve for the initial 508 of conversion degree of NC can be described by the first order autocatalytic equation magnified image and that for the latter 50% conversion degree of NC described by the reaction equations magnified image.
Theoretical Study on the Mechanism of the Cycloaddition Reaction between Alkylidene Carbene and Ethylene
Authors: Lu Xiu‐Hui , Zhai Li‐Min , Wu Wei‐Rong
Published: September 2010

The mechanism of cycloaddition reaction between singlet alkylidene carbene and ethylene has been investigated with second‐order Moller‐Plesset perturbation theory (MP2). By using 6–31G* basis, geometry optimization, vibrational analysis and energetics have been calculated for the involved stationary points on the potential energy surface. The results show that the title reaction has two major competition channels. An energy‐rich intermediate (INT) is firstly formed between alkylidene carbene and ethylene through a barrier‐free exothermic reaction of 63.62 kJ/mol, and the intermediate then isomerizes to a three‐membered ring product (Pl) and a four‐membered ring product (P2) via transition state TS1 and TS2, in which energy barriers are 47.00 and 51.02 kl/mol. respectively. PI is the main product.
Application of Ultrasonic Attenuation Measurements in the Studies on Macromolecular Conformational Behaviors —Phase Behavior of the Aqueous Solution of Poly(vinyl methyl ether) Sensitive to Temperature and the Modification of the Behavior by Using Poly(acrylic acid)
Authors: Wang Gong‐Zheng , Fang Yu , Shang Zhi‐Yuan , Zhang Mng , Hu Dao‐Dao
Published: September 2010

The phase behavior of the aqueous solution of poly(vinyl methyl ether) (PVME) sensitive to temperature and the modification of the behavior by using poly(acrylic acid) (PAA) have been studied by ultrasonic attenuation measurements and fluorescence probe techniques. It has been observed that PVME solution is transparent at mom temperature and becomes turbid upon heating. The solution turns clear again as smn as the temperature is decreased to room temperature. The heating and cooling process can be repeated for many times. The phase behavior of the solution sensitive to temperature is attributed to the conformational changes of the polymer. PVME may adopt an open coil conformation at mom temperature. With this conformation, the polymer is well miscible with the solvent, water, and thereby the system is a real solution. The polymer may adopt a compact coil conformation when the temperature is higher than a specific value. which is called the LCST (the lower critical solution temperature) of PVME. In this case, the polymer tangles to each other and forms various aggregates, which can scatter incident light and ultrasonic waves greatly. resulting in the phase separation, Introduction of PAA decreases the temperature sensitivity of the phase behavior of the polymer. The nature of the inhibition is attributed to the complexation of PAA with PVME and the strong hydrophilicity of PAA. Results from fluorescence probe studies are in accordance with those from ultrasonic attenuation measurements, indicating again that the ultrasonic attenuation method can be successfully used for the qualitative studies of polymer conformations and complexation between polymers.
Preparation and Characterization of Divanadium Pentoxide Nanowires inside SBA‐15 Channels
Authors: Zhu Ka‐Ke , Yue Bin , Xie Song‐Hai , Zhang Si‐Yi , Zhang Biao , Jin Song‐Lin , He He‐Yong
Published: September 2010

One‐dimensional V2O5 nanowires have been synthesized inside the channels of mesoporous silica SBA‐15 through chemical approach, which involves aminosilylation of silanol groups on the silica surface, anchoring of isopoly acid, H6V10O28. by neutralization of basic amine groups, and thermal decomposition. The formation and physicochemical properties of the nanowires were monitored and studied by TG‐DTA, variable temperature in situ XRD, TEM, N2 sorption measurements and UV‐Vis DRS. The results indicate that V2O5 nanowires formed within SBA‐15 channels belong to orthorhombic polycrystal domains. The oxygen‐to‐metal charge transfer band of V2O5 nanowires shows a blue shift in comparison with bulk V2O5, which clearly exhibits the quantum size effect of nanowires.
Synthesis and Crystal Structure of the Copper Complex of 7,16‐Bis(2‐hydroxy‐5‐methylbenzyl)‐1,4,10,13‐tetraoxa‐7,16‐diazacyclooctadecane
Authors: Ma Shu‐Lan , Zhu Wen‐Xiang , Guo Qian‐Ling , Liu Ying‐Chun , Xu Miao‐Qiong
Published: September 2010

A lariat crown ether ligand 7.16‐bis (2‐hydroxy‐5‐methylbenzyl)‐1,4,10,13‐tetraoxa‐7,16‐diazacyclooctadecane (Ll) has been prepared via one‐pot Mannich reaction. Its copper(II) complex Cu‐Ll was synthesized and characterized by elemental analysis, IR and UV‐visible spectroscopy. The crystal structure of the complex has been determined by X‐ray diffraction analysis. The result shows that the copper(II) ion is six‐coordinated by two nitrogen and four oxygen atoms, two from the crown ether and the other two from the deprotonated phenolate anions, forming an elongated octahedral complex. Electrochemical study indicates that the complex undergoes reversible reduction in DMF solution.
Crystal Structures and Characterizations of Bis(1‐benzoyl‐methyl‐benzotriazole‐N3)dichoro Metal(ll) Complex: [MCl2‐‐(CsH4N3CH2COPh)2] [M=Zn(ll), Co(ll)]
Authors: Jian Fang‐Fang , Sun Ping‐Ping , Xiao Hai‐Lian , Jiao Kui
Published: September 2010

The structures of [MCl2(C6H4B3CH2COPh)2] [M=Zn(II) (1), Co(II) (2)] have been determined by X‐ray crystallography. They were characterized by elemental analysis, IR spectrum, electronic spectrum and thermogravimetric‐differential thermal analysis. They all crystallize in the triclinic system, space pup Pi, with lattice parameters a=0.9449(2) nm, b=1.1291(2) nm, c=1.3637(3) nm, α=111.70(3)°, β= 94.33(3)°, y=90.97(3), Z=2 for compound 1; a=0.9437(2) nm, b= 1.1277(2) nm, c= 1.3650(3) nm, a=111.76(3)°, β=94.50(3)°, y=90.80(3)°, Z=2 for compound 2. The metal ions are all coordinated by two C1−‐ anions and two nitrogen atoms of 1‐benzoylmethyl‐bentriazole ligands. forming the distorted tetrahedral geometry. The Zn—Cl and Zn—N bond lengths are 0.2209(2), 0.2210(2) nm and 0.2059(4), 0.2067(4) nm. respectively. The CO‐Cl 3 and Co–N bond lengths are 0.2215(2). 0.2222(2) nm and 0.2028(5), 0.2045(5) nm. respectively. The thermogravimetric (TG) data indicate that they are nearly similar in TG curve, and there are not structural transitions in the two compounds. They all have a high thd stability. But, there is little difference in DTG (differential thermogravimetric) curves of those two compounds. Elemental analysis, electronic and IR spectra are in agreement with the structural data.
Synthesis, Structure and Biological Activity of Zn(ll) Complex with Tris(benzimidazol‐2‐yl‐methyl)amine Ligand
Authors: Liu Xiao‐Lan , Zhao Ru , Liu Xiao‐Hong , Yue Jun‐Jie , Yin Yu‐Xin , Sun Yun , Sun Ming
Published: September 2010

A new Zn(II) mononuclear complex with tris(benzimidazol‐2‐yl‐methyl)amine (NTB) was synthesized with stoichiometry of [Zn(NTB)NO3]NO3 · DIPY · DMF (DIPY : 4,4′‐dipyridyl). The complex was characterized by elemental analysis, UV and IR spectra. The crystal structure was determined by using X‐ray diffraction analysis. The crystal structure indicates that four N atoms and one O atom coordinate to zinc ion to construct a distorted trigonal‐dipyramid configuration. Three nonprotonated N atoms from imidazole groups are in the equatorial plane, one alkylamino N atom and one O atom from NO3−‐ in the axial directions. The biological activity assay shows that this complex presents certain biological activity by means of pyrogallol autoxidation and it can be called a model compound of superoxide dismutase (SOD).
Fluorescence Quenching of Poly[2‐methoxy‐5–(2′‐ethylhexoxy)‐p‐phenylene vinylene] (MEH‐PPV) in Solutions
Authors: Li Sha‐Yu , Xiong Fei , Zhang Hai‐Rong , Lu Xue‐Fang , Li Yi , Yang Guo‐Qiang
Published: September 2010

Fluorescence quenching processes of poly[2‐methoxy‐5–(2′ethyl‐hexoxy)‐p‐phenylene vinylene] (MEH‐PPV) in solution by electron acceptors, O2 and acid, have been studied. Static quenching of the fluorescence from MEH‐PPV by an electron acceptor (DDQ or TCNE) occurs due to electron transfer from MEH‐PPV to the electron acceptor and this electron transfer quenching can be promoted by chloroform. Photooxidation takes place in the MEH‐PPV solution and singlet oxygen is an intermediate in the photooxidation. according to the results of ESR spectroscopy. Acid also plays an important role in the fluorescence quenching process of MEH‐PPV, by the protonation of the alkoxy groups in the molecular chain.
Studies on Synthesis and Photochromism of a Novel Class of Fulgimide: (Z)‐4‐Oxazolylfulgimide
Authors: Xiao Jun‐Ping , Han Yong , Chen Yi , Li Wen , Fan Mei‐Gong
Published: September 2010

A novel class of fulgimide, (Z)‐4‐oxazolylfulgimide ((Z)‐1‐benzyl‐4–isopropylidene‐3–[1–(2–aryl‐5–methyl‐oxazolyl)ethylidene]tetrahydropyrrole‐2, 5–dione), was synthesized by the reaction of (Z)‐4–oxazolyl fulgide (4–isopropylidene‐3–[1–(2–aryl‐5–methyloxazolyl)ethylidene]tetrahydrofuran‐2, 5–dione) with benzyl amine. Photochromic property of (Z)4–oxazolylfulgimide was studied. Compared with (Z)‐4–oxazolylfulgide, the absorption maximum of the colored form of (Z)‐4–oxazolylfulgimide is bathochromic‐shifted. Substituents on the aryl ring affect the absorption maximum of the open form and the colored form of (Z)‐4‐oxazolylfulgimide.
Michael‐Addition Reaction of Malononitrile with α,β‐Unsaturated Cycloketones Catalyzed by KF/Al2O3
Authors: Wang Xiang‐Shan , Shi Da‐Qing , Tu Shu‐Jiang
Published: September 2010

A series of KF/Al2O3catalyzed Michael‐addition reactions between malononitrile and α,β‐unsaturate cycloketones in DMF solution were studied. At room temperature, 2‐cyano‐3‐aryl‐3–(1, 2, 3, 4‐tetrahydronaphthalen‐1‐one‐2‐yl) propionitrile derivatives were synthesized by the reaction between 2‐arylmethylidene‐1, 2, 3, 4‐tetra‐hydronaphthalen‐l‐one and malononitrile. However, if the temperature was increased to 80 C, 2‐amino‐3‐cyano‐4‐aryl‐4H‐benzo[h]chromene derivatives were obtained in high yields. When the α,β‐unsaturated ketones were replaced by 2, 6‐biarylmethylidenecyclohexanone or 25‐biarylmethylidenecyclopentanone, another series of 2‐amino‐3‐cyano‐4H‐pyran derivatives was isolated successfully. The structures of the products were confirmed by X‐ray diffraction analysis.
Synthesis of Zeolite ZSM‐2 Using Zeolite NaX as Seeds
Authors: Yi Hong‐Jiang , Wu Tai‐Liu , Wang Li‐Ping , Sun Yao‐Jun
Published: September 2010

A method is presented for the synthesis of zeolite ZSM‐2 by adding zeolite X as seeds in the synthetic mixture containing both lithium and sodium. At the presence of zeolite X seeds, highly crystalline zeolite ZSM‐2 with composition of (0.3–0.7)Li2O·(0.7–0.3)Na2O·A12O3, · (2.5–4.0)SiO2 a nH2O can be obtained in a wide range of SiO2/Al2O3 ratios from 2.5 to 16, and the optimum Li2O/(Li2O+Na2O) fraction is between 0.3 and 0.7. The ZSM‐2 products were characterized by XRD. SEM, IR. 29Si MAS NMR and DTA/TG analysis etc. By 29Si MAS NMR spectroscopy, it was found that ZSM‐2 contained nearly equal FAU and EMT phase, and the Si/Al ratios in FAU were slightly lower than those in EMT domains in most cases. The lithium form zeolite ZSM‐2 has comparable N2 adsorption capacity with LiX.
Adsorption Study of Methane on Activated Meso‐carbon Microbeads by Density Functional Theory
Authors: Shao Xiao‐Hong , Huang Shi‐Ping , Shen Zhi‐Gang , Chen Jian‐Feng
Published: September 2010

A combined method of density functional theory (DFT) and statistics integral equation (SIE) for the determination of the pore size distribution (PSD) is developed based on the experimental adsorption data of nitrogen on activated mesocarbon microbead (AMCMB) at 77 K. The pores of AMCMB are described as slit‐shaped with PSD. Based on the PSD, methane adsorption and phase behavior are studied by the DR method. Both nitrogen and methane molecules are modeled as Lennard‐Jones spherical molecules. and the well‐known Steele's 10–4–3 potential is used to represent the interaction between the fluid molecule and the solid wall. In order to test the combined method and the PSD model, the Intelligent Gravimetric Analyzer (IGA‐003) was used to measure the adsorption of methane on the AMCMB. The DFT results are in good agreement with the experimental data. Based on these facts, we predict the adsorption amount of methane, which can reach 32.3 w at 299 K and 4 MPa. The results indicate that the AMCMBs are a good candidate for adsorptive storage of methane and natural gas. In addition, the capillary condensation and hysteresis phenomenon of methane are also observed at 74.05 K.
Simulations of Metal Cu in Heating Process
Authors: Zhang Tao , Wu Ai‐Ling , Guan Li , Qi Yuan‐Hua
Published: September 2010

Based on the Finnis‐Sinsclair (FS) many‐body potential model, the melting process of a system, which consists of 500 Cu atoms, controlled by period boundary condition has been simulated. The means of pair correlation function, mean square displacement and Honeycutt‐Anderson bonded pair have been used to characterize the melting behavior of Cu at different heating rates. The simulation indicates that melting point of metal Cu is 1444 K during a continuous heating process, and the calculated diffusion constant at the melting point is 4.31×10−‐9/s. These results are better than those from the EAM method, showing that the FS potential model works well in some disordered systems.
Analysis and Protection of One Thousand Hand Buddha in Dazu Stone Sculptures
Authors: Wang Li‐Qin , Dang Gao‐Chao , Wang Xiao‐Qi , Xi Zhou‐Kuan , Liang Guo‐Zheng
Published: September 2010

The components of the rock, the pigments, the gold foils and the adhesive of One Thousand Hand Buddha in Dazu stone sculptures, Chongqing. China, have been analyzed by X‐ray diffraction (XRD). X‐ray fluorescence (XW. infrared spectroscopy (IR), energy dispersive X‐ray analysis (EDX) and fiber optics reflectance spectroscopy (FORS). Furthermore, the weathering and degeneration of One Thousand Hand Buddha have been discussed and the protective methods have been provided. In this work some useful information to study on conservation of stone relics is given.
Highly Stereoselective Synthesis of Phenylseleno‐ and p‐Tolylsulfonyl Substituted 1,3‐Dienes from Functionalized Allyl Alcohols
Authors: Xie Mei‐Hua , Huang Xian
Published: September 2010

Phenylseleno‐ and p‐tolylsulfonyl substituted 1,3‐dienes were conveniently prepared with high stereoselectivity by the elimination reaction of phenylseleno‐ and p‐tolylsulfonyl substituted allyl alcohols in the presence of BF3 · Et2O in acetic anhydride. The products were characterized by 1H NMR, MS, IR and elemental analysis. The single crystal structure of 2a was determined by X‐ray diffraction analysis.
Three New Diterpenoids from Euphorbia wallichii
Authors: Wang Huan , Zhang Xiao‐Feng , Cai Xiang‐Hai , Ma Yun‐Bao , Luo Xiao‐Dong
Published: September 2010

Three new abietane diterpene lactones, 3α‐hydroxyjolkinolide A (1), ent‐8α, 14β‐dihydroxy‐ 13(15)‐ene‐16(12α)‐abietanolide (2) and ent‐8α, 14α‐dihydroxy‐13(15)‐ene‐16(12α)‐abietanolide (3) as well as a known abietane diterpene jolkinolide A (4) were isolated from the roots of Euphorbia wallichii. Their structures were elucidated on the basis of spectroscopic analysis.
Asymmetric Hydroformylation of Olefins Catalyzed by a Chiral Diphosphite‐Rhodium Complex
Authors: Yan Ming , Li Xing‐Shu , Chan‐Chi Albert Sun
Published: September 2010

A C2‐symmetrical aryl diphosphite derived from chiral binaphthol was prepared and its rhodium complex was used as catalysts in the asymmetric hydroformylation of olefin. High catalytic activity and good regioselectivity were observed. Up to 31.2% ee and 38.1% ee were achieved for the hydroformylation of 4‐fluoro‐styrene and vinyl acetate respectively. The influences of ligand‐to‐metal ratio, reaction temperature and the pressure of syn‐gas on the enantioselectivity and regioselectivity were also studied.
Electrodeposition, Structure and Corrosion Resistance of Nanocrystalline Ni‐W Alloy
Authors: Yang Fang‐Zu , Guo Yi Fei , Huang Ling , Xu Shu‐Kai , Zhou Shao‐Min
Published: September 2010

Ni—W alloy was electrodeposited from the electrolyte solution containing sodium tungstate, nickel sulfate and ammonium citrate. The electrodeposition, heat treatment, structure, surface morphology and corrosion resistance in w=0.03 NaCl solution, of Ni—W alloys were studied by means of DSC, XRD, SEM and electrochemical techniques. The results showed that the obtained Ni—W alloy electrodeposit with W weight content (ww=0.471) was presented in more typical nanocrystalline. After heat treatment at 400 C for 1 h, the phase structure of the deposits was not obviously changed whereas the agglomerate for the reunion of tiny grains on deposit surface caused the granule in a more smooth morphology, the microhardness was slightly increased and the corrosion resistance was enhanced.
Li3AIB2O6: Synthesis, Crystal Structure, and Its Luminescence Property Compared with LiSrBO3
Authors: Wang Hai‐Xia , Cheng Wen‐Dan , Chen Da‐Gui , Zhang Hao , Wu Dong‐Sheng , Gong Ya‐Jin
Published: September 2010

The synthesis and crystal structure of Li3AlB2O6 with different cell parameters are reported and these cells are transformed each other from the confirmation of crystallographic structural analyses. The absorption spectrum, luminescence and lifetimes of the Li3AlB2O6 and LiSrBO3 solid compounds are measured and the comparisons are made between them. It is shown that the absorption edges are at about 400 run (or band gap 3.1 eV) and there is one of absorption peaks at about 350 run for the Li3AlB2O6 and LiSrBO3. The emission band (530 nm) makes a red shift and fluorescence decay time (24.39 ns) of the Li3AIB2O6 becomes smaller compound with the emission band (480 nm) and lifetime (93.16 ns) of the LiSrBO3 at the visible region. The transition energies and oscillator strengths of the clusters (Li3AlB2O6)2 and (LiSrBO3)2 lying at low excited states are calculated by the time‐dependent Har‐tree‐Fock method. The obtained results arc used to model the photophysical properties and discuss the origin of spectral bands of the Li3AlB2O6 and LiSrBO3.
Nanostructure Pt Electrode Obtained via Self‐assembly of Nanoparticles on Conductive Oxide‐coated Glass Substrate
Authors: Wang Wei‐Bo , Luo Zhen , Xiao Xu‐Rui , Lin Yuan
Published: September 2010

Self‐assembly of platinum nanoparticles were applied to fabrication of counter electrode for dye‐sensitized solar cells on conductive oxide‐coated glass substrate. The present Pt electrode exhibits high exchange current density of 220 mA/cm2, which is comparable to those prepared by electrodeposition. magnetron sputtering or thermal decomposition of platinum chloride. After analysis by transmission electron microscopy (TEM). atomic force microscopy (AFM) and X‐ray photoelectron spectroscopy (XPS), it was found that the catalyst was structurally characterized as nanosized platinum metal clusters and was continuously arranged on electrode surface. The present nanostructure electrode had high electrocatalytic activity for the reduction of iodine in organic solution.
Molten Salt Synthesis, Crystal Structure and Optical Properties of a Novel Quaternary Metal Selenide, K2AgIn3Se6
Authors: Guo Hong‐You , Wang Zhi‐Xia , Shu Gui‐Ming , Wang Ru‐Ji , Zhang Li‐Dan , Wang Ping
Published: September 2010

K2AgIn3Se6 was synthesized by a molten‐salt (alkali‐metal polyselenide flux) reaction at 500 C. The orange red granular crystal crystallizes in monoclinic space group C2/c with cell parameters, a =1.16411(7) nm, b= 1.16348(8) nm, c=2.14179(12) nm, V=2.8740(9) nm3, and Z=8. The crystal has a new two‐dimensional structure containing 2‐−[AgInSe6]2‐− anionic layers separated by K+ cations and the 2‐−[AgIn3Se6]2‐− layer is constructed with comer‐shared [AgSe4] and [InSe4] tetrahedra. The optical band gap of K2AgIn3Se6 was determined to be ca. 2.9 eV by UV/vis/NIR diffuse reflectance spectra.
Intrinsic Surface Reaction Constant in 1‐pK Model of Mg‐Fe Hydrotalcite‐like Compounds
Authors: Hou Wan‐Guo , Han Shu‐Hua , Li Dong‐Xiang , Zhang Gao‐Yong
Published: September 2010

The relationship among intrinsic surface reaction constant (K) in 1‐pK model, point of zero net charge (PZNC) and structural charge density (σst) for amphoteric solid with structural charges was established in order to investigate the effect of σst on pK. The theoretical analysis based on 1‐pK model indicates that the independent PZNC of electrolyte concenmtion (c) exists for amphoteric solid with structural charges. A common intersection point (CIP) should appear on the acid‐base titration curves at different c. and the pH at the CIP is pHPZNC. The pK can be expressed as pK=‐pHPZNC+log[(l+2αPZNC)/(1–2αPZNC)], where α‐PZNC σ/eNANs, in which e is the elementary charge, Na the Avogadro's constant and NS the total density of surface sites. For solids without structural charges, pK=‐ pHPZNC. The pK values of hydrotalcite‐like compounds (HTlc) with general formula of [Mg1‐x Fex(OH)2](Cl, OH)x were evaluated. With increasing x. the pK increases, which can be explained based on the affinity of metal cations for H− or OH− and the electrostatic interaction between charging surface and H− or OH−.
An Efficient Synthesis of [1, 2, 4]Triazolo[3, 2=d][1, 5]benzoxazepin‐2‐thiones, a Kind of Novel Tricyclic O, N‐Heterocycles
Authors: Li Zheng , Meng Qing‐Qing , Wang Quan‐Rui , Tao Feng‐Gang
Published: September 2010

A series of novel tricyclic O, N‐heterocycles, [1, 2, 4]triazolo[3.2‐d][1, 5]benzoxazepin‐2‐thiones 7 were achieved via acid‐induced ring closure of the geminal arylazo isothiocyanate compounds 5 which were derived from substituted chroman‐4‐ones. followed by feasible ring expansion with simultaneous insertion of the nitrogen atom into the carbon skeleton. The X‐ray crystal structure of 7d was also described.
Two Typical Examples of Scaling Ionic Partition Scheme for Estimating Correlation Energy of A2 Type Molecules
Authors: Zhuo Shu‐Ping , Si Wei‐Jiang , Wei Ji‐Chong , Ju Guan‐Zhi
Published: September 2010

Based on the calculation results of pair correlation energy contributions of the various electron pairs in Naz and H2NNH2 systems and the application of the scaling ionic partition scheme for symmetrical A2 type systems, the total correlation energies of Na2 and H2NNH2 have been reproduced by using this simple scheme. The two results show that the absolute deviations are within an acceptable range of mr, however, in this way, more than 90% of computational work can be. saved. The most attractive result in present paper is that, in these two molecules the coefficients c1 and c2 in the estimation equation can be obtained by the proportion of correlation energy of A− to that of A+ singlet system. Therefore, it is believed that the proposed ionic partition scheme for symmetrical A2 molecules would be very useful to estimate the correlation energies of large symmetrical molecules.
IR and Raman Vibrational Assignments for Metal‐free Phthalocyanine from Density Functional B3LYP/6‐31G(d) Method
Authors: Zhang Xian‐Xi , Bao Meng , Pan Na , Zhang Yue‐Xing , Jiang Jian‐Zhuang
Published: September 2010

Vibrational (IR and Raman) spectra for the metal‐free phthalocyanine (H2Pc) have been comparatively investigated through experimental and theoretical methods. The frequencies and intensities were calculated at density functional B3LYP level using the 6‐31G(d) basis set. The calculated vibrational frequencies were scaled by the factor 0.9613 and compared with the experimental result. In the IR spectrum, the characteristic IR band at 1008 cm−1 is interpreted as C—N (pyrrole) in‐plane bending vibration, in contrast with the traditional assigned N—H in‐plane or out‐of‐plane bending vibration. The band at 874 cm−1 is attributed to the isoindole deformation and aza vibration. In the Raman spectrum, the bands at 540. 566, 1310, 1340, 1425, 1448 and 1618 cm−1 are also re‐interpreted. Assignments of vibrational bands in the IR and Raman spectra are given based on density functional calculations for the first time. The present work provides valuable information to the traditional empirical assignment and will be helpful for further investigation of the vibration spectra of phthalocyanine analogues and their metal complexes.
Ab Initio and Density Functional Study on the First Hyperpolarizabilities of Squaric Acid Homologues
Authors: Fu Wei‐Wei , Zhou Li‐Xin
Published: September 2010

The first hyperpolarizabilities of four squaric acid homologues: squaric acid, 1, 2‐dithiosquaric acid, 1, 2‐diselenosquaric acid and 1,2‐ditellurosquaric acid have been calculated using ab initio and DFT methods. The effects of equilibrium geometries. basis set and electron correlation on the first hyperpolarizabilities of these molecules were investigated. The frequency dispersion effect and solvent effect, which are essential to get reliable outputs in comparison to the experimental results, have also been explored. On the basis of these investigations, it is worthy to point out that the heavy atom effect takes effect for these squaric acid homologues.
Synthesis, Characterization and Crystal Structure of (Z)‐1‐[2–(Triarylstannyl)vinyl]‐1‐indanols and Their Arylhalostannyl Derivatives
Authors: Zhu Dong‐Sheng , Lu Chun‐Sheng , Mei Ze‐Min , Gao Wei , Zhang Yue‐Tao , Mu Ying , Wang Zong‐Mu
Published: September 2010

(Z)‐1‐[2‐(Tri‐o‐tolylstannyl)vinyl]‐l‐indanol(1) and (Z)‐1‐[2‐(tri‐p‐tolylstannyl)vinyl]‐l‐indanol (2) were synthesized by the addition reaction of l‐ethynylindanol with tri‐o‐tolyltin and m‐p‐tolyltin hydride. The aryl groups in compound 1 and 2 were substituted by Br2 or I2 to yield monohalide derivatives (3–6). The compounds 1–6 were characterized by elemental analysis, 1H NMR and FT‐IR spectroscopy. The crystal structures of 1, 2 and 4 have been determined by single crystal X‐ray diffraction analysis. The Sn atom in 1 and 2 exhibits a tetrahedral geometry distorted towards trigonal bipyramid due to a weak intramolecular interaction between Sn and the hydroxyl O atoms [02839(4) nm and 0.2744(5) nm], while the Sn atom in 4 adopts a trigonal bipyramidal geometry with a significant 0→Sn(1) interaction [0.2552(5) nm].
Synthesis, Characterization and Two‐Photon Absorption Properties of a Novel Pyridinium Salt
Authors: Hao Fu‐Vinga , Shi Peng‐Fei , Liu Hui‐Jun , Wu Jie‐Mng , Yang Jia‐Xiang , Tian Yu‐Peng , Zhou Guang‐Yong , Jiang Min‐Huk , Kun Hoong Fun , Suchada Chantraptomma
Published: September 2010

A novel pyridinium salt, 2,4‐bis[p‐(N,N‐dimethylamino)styryl]‐N‐methyl pyridinium iodide (BMSPI) was synthesized and characterized by TG, 1H NMR spectroscopy and elemental analysis. and the reaction process was studied by Using ES‐MS. When BMSPI was pumped by a pulsed 1064 nm, 50 ps laser him. it manifests highly efficient TPA (Two‐Photon Absorption) and up‐conversion superradiance. The up‐conversion efficiency was 6.0% at the pump energy of 4–6 mJ and the Lifetime of two‐photon fluorescence was measured as 59 ps.
A Valuable Synthetic Route to the Enantiopure Functionalized N‐Substituted Aziridines
Authors: Li Sen‐Lan , Guo Jin‐Bo , Yu Zhao‐Uan , Chen Qing‐Hua
Published: September 2010

Chiral butyrolacto[3,4‐b]‐2(S)‐6(R)‐l‐N‐alkylaziridines 7 were synthesized in enantiopure form utilizing racemic 5‐methoxy‐3‐bromo‐2(5H)furanone (5) and available amines (6) as key precursors. After highly effective reduction of 7, the functionalized 2(S),3(R)‐dihydroxymethyl‐N‐alkylaziridines (8) were obtained in good yields with ≥98% ee. This is a simple and practical method for the preparation of enantiopure aziridines which are important intermediates in the synthesis of biologic active molecules.