bluuebunny/crossref_metadata_2025 huggingface dataset:
A generalized mathematical model for non‐catalytic gas‐solid reactions
Authors: Zi‐Feng Yan , Jie‐Qing Lu , Max G. Q. Lu
Published: September 2010

Based on a general classification and characteristic comparison of the existing models, a new model for non‐catalytic gas‐solid reactions is proposed and a general formulation for the model in terms of the solid conversion, X, is presented in mis paper. The model, referred to the generalized model, is demonstrated to be applicable to any solid reactant of general structure ranging from highly porous to nonporous materials. It is shown that the generalized model incorporates the grain and pore structure for a solid pellet and can be reduced to the grain and random pore models as extreme cases.
Preconcentration and separation of trace Pd(II) and Pt(IV) with silica, gel bonded by aminopropyl‐benzoylazo‐4‐(2‐pyridylazo)‐resorcinol
Authors: Feng Li Lhj , Ke‐An  , Wen Chen , Yan‐Sheng Wu , Tuan‐Li Yao , Shen‐Yang Tong
Published: September 2010

This paper reports a simple and highly selective method for preconcentrating and separating of trace Pd(II) and Pt(IV) with silica gel bonded by aminopropyl‐benzoylazo‐4‐(2‐pyridylazo)‐resorcinol (ABPR·SG). ABPR·SG is stable in solution from 6 mol/L HCl to pH 7.0 and in common organic solvents. The maximum adsorptive capacity of Pd(II) on ABPRSG is 362 μmol/g. After preconcentrating and separation by using ABPR·SG column, Pd(II) and Pt(IV) of μg/L level in artificial water samples can be measured reliably by common spectrophotometer. The maximum concentration factors of Pd(II) and Pt(IV) on ABPR·SG column are 143 and 125 respectively. The chromatographic column packed with ABPR·SG can be reused. The method is simple and efficient.
Studies on the effect of surfactants on the extraction rate by laser thermal lens spectrometry
Authors: Hong‐Tao Yan , Xin Tian , Yong‐Feng Wei
Published: September 2010

The effect of different kinds of surfactants on the extraction process of Nile Blue‐I was investigated by laser thermal lens spectrometry. It was shown that the surfactants could accelerate or decelerate the extraction rate by varying the extractive's solubility and the intrafacial tension of the extraction solution. The higher the concentration of surfactants was, the more obvious the effect.
Epoxidation of allyl chloride with H2O2 on Ti‐ZSM‐5 prepared by the isomorphous substitution
Authors: Cheng‐Hua Xu , Shao‐Jie Lü , Gui‐Ying Deng , Fa‐Li Qiu
Published: September 2010

The epoxidation of allyl chloride with H2O2 on Ti‐ZSM‐5 prepared by isomorphous substitution of HZSM‐5 with TiCl4 gas was studied. The results show that Ti‐ZSM‐5 has a high catalytic efficiency for the epoxidation of allyl chloride. The H2O2 utilization reaches 99.50% when the allyl chloride/H2O2 molar ratio is > 1. The effect of solvent species, catalyst concentration, H2O2 and allyl chloride concentration and reaction temperature on the epoxidation was investigated simultaneously. It is found that methanol is the best solvent for the reaction. The reaction rate equation with v = k[Cat.][H2O2]1/2‐[ C3H5a] and the apparent activation energy with Ea= 63.462 kJ/mol are obtained according to the kinetics study.
Effect of solvent on the free energy of activation of SN2 reaction between phenacyl bromide and amines
Authors: Asadollah Nasehzadeh , Abbas Chahardoli
Published: September 2010

The kinetics of SN2 reaction between phenacyl bromide and various amines in 12 different solvents were studied. Solvent effects on the rate of this reaction and free energy of activation, ΔG#, were interpreted by applying the Abraham‐Kamlet‐Taft (AKT) equation. The solvent polarity (π1*), solvent hydrogen‐bond basicity (β1) and Hildebrand cohesive density energy (δ2H) are those parameters which increase the rate constant and decrease ΔG#, while solvent hydrogen‐bond acidity (α1) will have the compensatory effect. A comparison among obtained values of second rate constants, k2 for different amines in a given solvent indicates that the amine reactivities are highly dependent on their structures. The consequent decrease of the rate constant for different amines in any given solvent was found to be: primary > secondary > tertiary. This order results from steric effects of amines.
A new alkaloid and arbutin from the whole plant of Huperzia serrata
Authors: Wen‐Yun Gao , Bao‐De Wang , Yi‐Ming Li , Shan‐Hao Jiang , Da‐Yuan Zhu
Published: September 2010

A new Lycopodium alkaloid together with a phenolic glycoside—arbutin, were isolated from the whole plant of Huperzia serrata. The new compound was assigned the trivial name of huperzine I. The structures of these two compounds were determined on the basis of spectral evidence.
Hydrophobically modified polyelectrolytes III. Reactivity ratio determination of FX14/AA, LA/AA and SA/AA
Authors: Dong‐Qing Zhuang , Li‐Ping Shi , Yi‐Hua Yu , Yun‐Xiang Zhang
Published: September 2010

The reactivity ratios of three hydrophobic monomers, FX14, LA and SA, to hydrophilic monomer, acrylic acid (AA), were determined. For the fluorocarbon containing hydrophobic monomer FX14, elemental analysis was adopted to obtain the relative content of FX14 to AA. For two hydrocarbon monomers, 13C NMR was used. FR, KT linear method and EVM nonlinear method were applied in calculating reactivity ratios. It is found that the reactivity of LA and SA is lower than that of AA, for solution polymerization in cyclohexane. Whereas FX14 is more reactive than AA in benzene. Finally, the distribution of small amounts of these hydrophobic monomers along the polymeric chain is discussed and a random sequence is confirmed
Synthesis of C2 oxygenated compounds from syngas in supercritical cyclohexane
Authors: Xiu‐Zhi Wang , Wei Wei , Jie Chang , Xiao‐Ping Chen , Jie Ren , Yu‐Han Sun , Bing Zhong
Published: September 2010

Catalytic synthesis of C2 oxygenated compounds from syngas in supercritical cyclohexane was reported in this paper. The effect of the molar ratio of media to feed on the conversion and selectivity was mainly discussed. The results showed that the selectivity of C2 oxygenated compounds in supercritical cyclo‐hexane was greatly improved, and the by‐products of acetic acid, acetic ester and alkanes were efficiency suppressed. Although the CO conversion was slightly declined, the space‐time yield of C2 oxygenated compounds basically kept the constant at high media/feed ratio.
Chemically induced dynamic electron polarization investigation of the triplet‐radical system in the solution of the triplet quencher
Authors: Zhang Xian‐Yi , Xu Xin‐Sheng , Cui Zhi‐Feng , Lu Tong‐Xing
Published: September 2010

The chemically induced dynamic electron polarization (CIDEP) of the triplet molecule/triplet quencher/2, 2, 6, 6‐tetramethyl‐1‐piperidinyloxyl (TEMPO) systems were measured using the high time‐resolved ESR spectrometer. The competition between the radical‐triplet pair mechanism (RTPM) and triplet mechanism (TM) or radical pair mechanism (KIM) polarization in the solution of the triplet quencher was investigated, and the relationships between reaction rate of the radical‐triplet pair and quenching rate of triplet was deduced.
Polymeric bilayer modified microelectrodes for in‐vivo determination of neurotransmitter dopamine
Authors: Yang Li‐Ju , Peng Tu‐Zbi , Catherine Yang F.
Published: September 2010

A composite polymer carbon fiber electrode modified with Nafion and cellulose acetate is described. The modified electrode discriminates against both anionic reactants and big molecular organic compounds. The bilayer configuration is prepared in two steps. First, the carbon fiber electrode is coated with Nation, men followed by air evaporation of the solvent, me electrode is dipped in a cellulose acetate solution and hydrolyzed for a selected time. The permeability of the film is explored by use of rotating disk electrode measurements. Parameters affecting the film electrochemistry are investigated. The resulting electrodes show high selectivity and stability in body fluids. For in‐vivo voltammetry, the composite polymer modified electrode has been used for detection of me oxidative current of neurotransmitter dopamine in rat brain, while it inhabits the oxidation of an°C neurotransmitter metabolites and some electroactive compounds.
Coordination chemistry of organometallic polydentate ligand Reactive chemistry of the tridentate ligand trans‐Fe(Ph2PQu‐P)2‐(CO)3 [PhzPQu=2‐diphenyl‐phosphino‐4‐methylquinoline] and molecular structure of [Fe(CO)3(μ‐Ph2PQu)2HgI]+ [HgI3]
Authors: Xu Feng‐Bo , Sun Li‐Juan , Xuan Zhen‐Ai , Zhang Wei‐Dong , Cheng Hui , Zhang Zheng‐Zhi
Published: September 2010

Reaction of a new type of bidentate ligand PhPQu [PhPQu = 2‐diphenylphosphino‐4‐methylquinoline] with Fe(CO)5 in butanol gave trans‐Fe(FpPQu‐P)(CO)3 (1). Compound 1, which can act as a neutral tridentate organometallic ligand, was reacted with I B, II B metal compounds and a rhodium complex to give six binuclear complexes with FeM bonds, Fe(CO)3 (μ‐Ph2PQu)MXn (2–7) [M= Zn(II), Cd(II), Hg(II), Cu(I), Ag(I), Rh(I)], and an ion‐pair complex [Fe(CO)3 (μ‐Ph2PQu)2HgI][HgI3]− (8). The structure of 8 was determined by X‐ray crystallography. Complex 8 crystallizes in the space group P‐1 with a = 1.0758(3), b = 1.6210(4), c=1.7155(4)nm; a=75.60(2), β=71.81(2), γ=81.78(2)° and Z = 2 and its structure was refined to give agreement factors of R=0.050 and Rw = 0.057. The Fe‐Hg bond distance is 0.2536nm.
Template synthesis and cocatalytic behavior of phosphorus donor containing trans‐Fe(0) metallacrown ethers
Authors: Xu Feng‐Bo , Zhang Li‐Fang , Sun Li‐Juan , Xuan Zhen‐Ai , Zhang Zheng‐Zhi , Zhao Wei‐Jun
Published: September 2010

Same new phosphorus donors containing trans‐Fe(0) metallacrown ethers were obtained by template synthesis. The co‐catalytic properties of these complexes and the X‐ray diffraction structure of complex 1 were discussed.
Synthesis, characterization and catalytic applications of tridentate Schiff base derivatives of bis and mono(cyclopentadienyl)‐lanthanocene complexes
Authors: Yousaf Muhammad , Liu Qian‐Cai , Huang Ji‐Ling , Qian Yan‐Long
Published: September 2010

Seven kinds of lanthanocene complexes were prepared by the reaction of tridentate Schiff base | N‐(2‐methoxyphenyl)salicylideneamine with tris(cyclopentadienyl) lanthanide tetrahydrofuranate or bis (cyclopentadienyl) lanthanide chloride tetrahydrofuranate in THF. All the complexes were characterized by MS, EA and IR respectively. The structure of |Cp2LnC14U13NO2) Ln = Sm, Dy, Y, Er| (1–4) was further confirmed by X‐ray determination of Cp2Sm(C14H13NO2) (1) which indicates that the complex is monomeric in which central metal is coordinatively saturated by two cyclopentadienyl rings, two oxygens and one nitrogen of the ligand. The isomerization of 1,5‐hexadiene explains that complexes (1–4) isomerize this monomer into a mixture of 1,4‐hexadiene, 2,4‐hexadiene, 1,3‐hexadiene, methylenecyclopentane and methyl–cyclopentene. Similarity complexes |CpLn(a) C14 H13NO2) (THF) (Ln=Sm, Dy, Y, Er)| (5–7) polymerize methyl‐methacrylate (MMA) to give polyMMA (PMMA) in 51.8% yield and high molecular weight (274 × 103), which shows narrow molecular weight distributions and partially syndiotactic.
Synthesis and structural characterization of a novel dimolybdenum(I) compound with mixed‐tribridging ligands: [Bu4N][Mo2(μ‐SPh)2(μ‐Cl(CO6]
Authors: Pan Guo‐Hua , Zhuag Bo‐Tao , He Ling‐Jie , Chen Jiu‐Tong , Lu Jia‐Xi
Published: September 2010

A novel mixed‐tribridged dimolybdenum(I) compound [Bn4N][Mo2(μ‐SPh)2(μ‐Cl)(CO)6] (1) has been synthesized from the reaction of Mo2(CO)3(SPh)2 with BU4NCl. Compound 1 was characterized by IR, UV‐Vis and 1H, 13C, 95Mo NMR spectroscopic analyses. The electrochemical behavior was measured by cyclic voltammetry, indicating a quasi‐reversible two‐electron transfer in one step. The crystal structure determined by X‐ray crystallography shows that 1 contains a [Mo2(μ‐S)2(μ‐Cl)]− core with a planar Mo2S2unit and a Cl bridge. The MoMo distance is 0.28709(7) nm, and the Mo‐Cl‐Mo angle is 66.44(4)°. A newface‐sharing bioctahedral structure is discussed.
Oxidation of N‐benzyl groups
Authors: Qiu Wen‐Ge , Chen Shu‐Sen , Yu Yong‐Zhong
Published: September 2010

The additive reactivity of 2,6,8,12‐tetraacetyl‐4, 10‐dibenzyl‐2,4,6,8,10,12‐hexazatetracyclo [5.5.0.05.9. 03.11] dodecane (3) in several conditions was studied. It was found that the N‐benzyl groups in compound 3 could be oxidized to benzoyl groups by Cr(VI) reagents, and could be removed by cerium ammonium nitrate (CAN), meanwhile nitroamine products were given.
Polymerization of MMA catalyzed by different novel mixed ligand lanthanocene {(Cp) (Cl) LnSchiff‐base (THF)}, (COT)‐Ln(methoxyethylindenyl) (THF)/Al(i‐Bu)3 systems
Authors: Yousaf Muhammad , Huang Ji‐Uag , Feng Zuo‐Feng , Qian Yan‐Long , Sun Jun‐Quan , Pan Zhi‐Da
Published: September 2010

This article deals that the rare earth metal complexes along with Al (i‐Bu)3 can catalyze the polymerization of methyl‐methacrylate (MMA) into high molecular weight poly(MMA) along with narrow molecular weight distributions (MWD). A typical example was mentioned in the case of {Cp(Cl) Sm‐Schiff‐base(THF)} which expresses maximum (conv. % = 55.46 and Mn = 354 × 103) efficiency along with narrow MWD (Mw/Mn < 2) at 60°C. The resulting polymer was partially syndiotactic (>60%). The effect of the catalyst, temperature, catalyst/MMA molar ratio, catalyst/Al(i‐Bu)3 molar ratio on the polymerization of MMA at 60°C were also investigated.
A novel oxygen‐dependent deoximation by nitric oxide
Authors: Mao Yu‐Zhu , Liu Zhong‐Ii , Wu Long‐Min
Published: September 2010

A variety of aldoximes and ketoximes were oxidized to corresponding aldehydes and ketones by nitric oxide in the presence of oxygen. A presumed mechanism was suggested.
Synthesis, crystal structures and spectral properties of cobalt (II) complexes: [ Col (N3) ] · ClO4 and CoL (N3) 2 [L = tris( (3,5‐dimethylpyrazol‐1‐yl) methyl)amine]
Authors: Zhang Zhi‐Hui , Yang Hai‐Long , Ma Zhi‐Hong , Qi Ai‐Di
Published: September 2010

Two monomeric cobalt(II) complexes, [CoL(N3)]ClO4 (1) and CoL(N3)2 (2), where L is tris((3,5‐dimethylpyrazol‐yl) methyl) amine, were synthesized and their crystal structures were determined by X‐ray diffraction technique. Complex 1 is five coordinated with one azide nitrogen atom and four nitrogen atoms of the tris((3,5‐dimethyipyrazol‐1‐yl)‐methyl) amine ligand, and the metal center is in distorted trigonal bipyramidal environment. Complex 2 is six coordinated distorted octahedron with the two azide nitrogen atoms and four nitrogen donors of the tris((3,5‐dimethylpyrazol‐l‐yl)‐methyl) amine ligand. The solution behaviors of the title complexes have been further investigated by UV‐Vis, and 1H NMR analysis. It is found that the formation of 1 and 2 depends on the molar ratio of the azide ion to metal salt and ligand. Complex 1 attached with one aside group is more stable and easy to generate than complex 2 incorporated with two azide groups, and the reasons were well discussed.
Metal compound‐mediated hydrolytic cleavage of oxidized insulin B chain: Regioselectivity and influence of peptide secondary structure
Authors: Luo Xue‐Mei , He Wd‐Jiang , Zhang Yu , Guo Zi‐Jian , Zhu Long‐Gen
Published: September 2010

The interaction of oxidized insulin B chain (B) with cis‐[Pd(en)Cl2] (en=ethylenediamine), cis‐[Pd‐(dtco‐3‐OH)Cl2] (dtco‐3‐OH= dithiacyclooctan‐3‐ol) and CuCl2 was studied by electrospray mass spectrometry. It is discovered that the binding of Pd(II) complexes and the sites of cleavage are highly dependent on the secondary structure and local environment of B. The hydrolytic cleavage of denatured B by Pd(II) complexes was monitored by HPLC. The reaction is regioselective and follows first order kinetics with half‐life of 4.8 days at 40oC. Two amide bonds, i. e. at Leu6‐Cys7 and at Gly8‐Ser9, which are dose to the two potential Pd(II) binding sites His5 and His10, are selectively cleaved. In the case of Cu(II) ion as promoter, only one cleavage site was observed which is located at Gly8‐Ser9 bond. These results provide improved understanding on the design of artificial metallopeptidase.
Study on surface acid‐base property of carboxylic acid‐terminated self‐assembled monolayers by cyclic voltammetry and electrochemical impedance spectroscopy
Authors: Luo Ii‐Qiang , Cheng Zhi‐Liang , Yang Xiu‐Rong , Wang Er‐Kang
Published: September 2010

Cyclic voltammetry and electrochemical impedance spectroscopy were used to study the surface acid‐base property of carboxylic acid‐terminated self‐assembled monolayers (SAMs). A carboxylic acid‐terminated thiol, such as thioctic acid (l,2‐dithiolane‐3‐pentanoic acid), was self‐assembled on gold electrodes. Electron transfer between the bulk solution and the SAM modified electrode was studied at different pH using Fe(CN)63− as a probe. The surface pKa. of thioctic acid was determined by cyclic voltammetry and electrochemical impedance spectroscopy to be 5.6 ± 0.1 and 5.8 ± 0.1, respectively. The method is compared with other methods of monolayer pKa measurement.
Dysamide U, a new trichlorinated diketopiperazine from the sponge Dysidea sp
Authors: Fu Xiong , Su Jing‐Yu , Zeng Long‐Mei
Published: September 2010

Dysamide U, a new trichlorinated diketopiperazine (1) along with seven known ones (2–8) were isolated from the sponge of Dysidea sp. collected from the Pacific ocean. The structure of dysamide U (l) was elucidated by high resolution FABMS and 1H NMR data including COSY and RCT‐COSY.
Rearrangement reaction of the hydroxyl group of α‐hydroxyalkyltriphenyl phosphonium bromides
Authors: He Mei‐Yu , Yuan Gu , He Xiao‐Ran
Published: September 2010

No molecular ion peak from the Electron Impact Ionization of eight ω‐hydroxyalkyltriphenyl phosphonium bromides (Ph3P+(CH2) OHBr, n=2–6, 8–10) can be found, except a part of some relative powerful fragment ions can be observed only. Each compound forms a very characteristic ion (O = PPh3 ‐ 1)+ at m/z 277 through hydroxyl rearrangement reaction. The intensity of this ion is closely related with the size of the carbon chain of hydroxyalkyl and with temperature of ion source and temperature of sample probe. The above rearrangement reaction and the reaction to form ion at m/z 262 take place simultaneously, thus leading to strong competition.

At n = 2, km at m/z 277 is the most powerful and becomes continuously the base peak. At n = 3 and n = 4, the intensity of ion at m/z 262 reaches the maximum, and is always the base peak, and the relative abundance of m/z 277 is only around 2% At n = 5, 6, 8, 9, 10, m/z 277 becomes base peak when the temperature of probe is below 300°. But, when the temperature increases from 300°C to 35oC, m/z 262 suddenly becomes the base peak, which is not in direct proportional relation with the size of carbon chain. It is proved by MIKES and accurate mass mat ion at m/z 277 produces a fragment ion (O = PPh2 ‐ 2) + at m/z 199 with the loss of the neutral benzene molecule.
Synthesis and mesomorphic properties of some ferroelectric liquid crystals of lactate
Authors: Li Heng‐Feng , Yang Yong‐Gang , Wen Jian‐Xun
Published: September 2010

A semiperfluorinated chain has been introduced into three series of lactate‐based molecules, and their mesomorphic properties have been studied by DSC and optical polarized microscope. An abnormal phenomenon has been found that the introduction of a triple bond in the core of the molecule, which lengthened the molecule, gave rise to a decrease in the thermal stability of chiral smectic C phase and smectic A phase. 2, 3‐Difluoro substituents of the phenylenic structure hinder the formation of the chiral smectic C phase because of the steric effect.
Synthesis and crystal structure of chain [Cu2I2(PPh3)2(C4H5N3)]∞
Authors: Jin Qiong‐Hua , Lu Xiao‐Ming , Zhu Hui‐Ju , Ji Xian‐Ping
Published: September 2010

The chain [Cu2I2 (PPh3 )2 (C4H5N3)]∞ has been synthesized and characterized by X‐ray crystallography. It crystallizes in the triclinic system, space group P1, with a =0.9985(2) nm, b = 1.0998(2) mn, c = 1.5174(2) nm, a = 87.89(1)°, β=76.73(1)°, γ = 77.77(1)°, V=1.5849(5) nm3, Z = 2, Dc = 2.095g/cm3. [Cu2I2(PPh3)2(C4H5N3)]∞ has a dimmer unit [Cu2I2(PPh3)2(C4H5N3)]. The two N atoms of the phenyl ring of 2‐aminopyrimidine bridge two [CuI(PPh3)]2 units, by which a one‐dimensional chain is constructed. The van der Waals force makes the molecules arrange in the three‐dimensional space.
Bite Angle Effects in Hydroformylation Catalysis
Authors: van Leeuwen Piet W. N. M. , Kamer Paul C. J. , van Der Veen Lars A. , Reek Joost N. H.
Published: September 2010

Recent advances in rhodium catalyzed hydroformylation using xanthene‐based ligands will be reviewed. The calculated natural bite angles of the ligands discussed are in the range 100–123°. While the general trend is clear—higher 1: b ratios at wider angles, small changes in the bite angle do not exhibit a regular effect on the selectivity of the reaction. The same is true for the rate of CO dissociation; the larger the rate of the CO dissociation, the larger the rate of hydroformylation, but for small changes the effects do not comply with this rule.
Development of a New Combinatorial Approach to Multifunctional Catalysts: Metal Silsesquioxanes as Precursors to Microporous Metallosilicates
Authors: Maxim Nicolae , Abbenhuis Hendrikus C. L. , Magusin Peter C. M. M. , van Santen Rutger A.
Published: September 2010

Microporous, silica‐supported metal oxides with a very narrow pore size distribution around 0.6 nm diameter, typical surface areas ranging from 350 to 700 m2/g, and loadings of well‐dispersed metal oxide (up to w = 10% of metal) result from the controlled calcination of silsesquioxane metal complexes. A versatile new methodology is envisioned that, in a combinatorial fashion, enables catalyst preparation with control over metal content and dispersity, together with adjustable Lewis and Brönsted acidity. In addition, the method is suitable for the preparation of bi and multifunctional catalysts containing different metals.
Oxidative Dehydrogenation of Ethane to Ethylene over LiCl/MnOx/PC Catalysts
Authors: Ge Qing‐Jie , Li Wen‐Zhao , Yu Chun‐Ying , Xu Heng‐Yong
Published: September 2010

The catalytic stability of LiCl/MnOx/PC catalyst have been investigated, the deactivation mechanism was discussed. The experimental results show that ethane conversion decreases and ethylene selectivity keeps about 90% as reaction time increases. The main deactivation reasons of LiCl/MnOx/PC catalyst for oxidative dehydrogenation of ethane (ODHE) to ethylene are the transition of active species Mn2O3 to MnO species and the loss of active component Cl in catalyst. Instead of ethane with FCC tailed‐gas, the stability of LiCl/MnOx/PC catalyst has been largely improved.
Synthesis of 1‐Methyl‐3‐aryl‐substituted Titanocene and Zirconocene Dichlorides and Crystal Structure of Bis[η5‐1‐methyl‐3‐(α, α‐dimethylbenzyl) cyclopentadienyl] titanium Dichloride
Authors: Qian Yan‐Long , Qin Xin‐Rong , Huang Ji‐Ling , Chan Albert Sun‐Chi , Chen Shou‐Shan , Wang Hong‐Gen
Published: September 2010

The syntheses of a series of l‐methyl‐3‐aryl‐substituted titanocene and zirconocene dichlorides are reported. These complexes are synthesized by the reaction of 2‐ and 3‐methyl‐6, 6‐dimethylfulvenes (1:4) with aryllithium, followed by the reaction with TiCl4·2THF, ZrCl4 and (CpTiCl2)2O respectively, to give complexes 1–5. The complex [η5‐1‐methyl‐3‐(α, α‐dimethylbenzyl) cyclopentadienyl] titanium dichloride has been studied by X‐ray diffraction. The red crystal of this complex is monoclinic, space group P2t/C with unit cell parameters: a =6.973(6) × 10−1 nm, b =36.91(2) × 10−1 nm, c = 10.063(4) × 10−1 nm, α=β= γ = 93.35(5)°, V = 2584(5) × 10−3 nm3 and Z = 4. Refinement for 1004 observed reflections gives the final R of 0.088. There are four independent molecules per unit cell.
Synthesis and Structure of Lanthanide Sandwich Complexes with Mixed Cyclooctatetraenyl and Chelating Substituted‐indenyl Ligands
Authors: Huang Ji‐Ling , Shen Xiao‐Qiang , Liu Qian‐Cai , Qian Yan‐Long , Chan Albert Sun‐Chi
Published: September 2010

Two types of sandwich complexes (η5‐MeOCH2CH2C9H6) Ln (η8‐C8H8) (THF)n [Ln=La (1), Nd(2), n=0; Sm(3), Dy (4) and Er (5). n = l] and (η5‐C4H7OCH2C9H6)Ln(η8‐C8H8) (THF) [Ln = La (6), Nd(7). Sm(8). Dy (9) and Er (10)] were synthesized by the reactions of LnCl3 with equivalent mole of K2C8H8, followed by treatment with corresponding potassium salt of ether‐substituted indenide. The molecular structures of 3 and 8 were determined by single crystal X‐ray diffraction. (η5 ‐MeOCH2CH2C9H6) Sm (η8‐C8H8) (THF) (3) monoclinic. Pt1/c, a = 1.4793(3) nm, b = 0.8716 (2) nm, c = 1.6149 (3) nm, β = 98. 17(3), V = 2.0612(7) nm3, Z = 4, R(F)=0.0362. (η5‐C4H7OCH2C9H6)Sm(η8‐C8H8)(THF) (8) orthorhombic. p212121. a = 0.8754(2) nm, b = 1.1000(2) nm, c = 2.3117 (5) nm, V = 2.2260(8) nm3, Z=4, R(F) =0.0497.
Synthesis of Distamycin Analogs and Their Interactions with Calf Thymus DNA
Authors: Xiao Jun‐Hua , Yuan Gu , Huang Wei‐Qiang , Du Wei‐Hong , Wang Bao‐Huai , Li Zhi‐Fen
Published: September 2010

Two distamycin analogs (PyPyPy‐γ‐Dp and PyPyPyPy‐γ‐Dp) were synthesized by a haloform reaction and the DCC/HOBT coupling reaction in a ample and fast way without amino protection. By using calf thymus DNA, the interaction between the analogs and DNA duplex was studied by CD, and ITC.
Concise and Effective Synthesis of 1→2 α‐Linked Mannopyranosyl Oligosaccharides and Related Antigenic Factor 34 and Dominant of Antigenic Factor 13
Authors: Zhu Yu‐Liang , Kong Fan‐Zuo
Published: September 2010

A highly concise and effective synthesis of 1 → 2 α‐linked mannopyranosyl oligosaccharides was achieved via TMSOTf promoted condensation of the corresponding benzoylated monosaccharide alkyl orthoester. 1→2 α‐Linked mannosyl di, trisaccharide, antigenic factor 34, and dominant of antigenic factor 13 were readily synthesized by the new method.
Speciation Analysis of Serum Copper by Ultrafiltration Combined with Graphite Furnace Atomic Absorption Spectrometry
Authors: Wang Zhi‐Hua , Ma Hui‐Min , Ma Quan‐Li , Liang Shu‐Chuan
Published: September 2010

Ultrafiltration combined with graphite furnace atomic absorption spectrometry (GFAAS) was used to study protein binding and speciation of copper in human serum. Ultrafiltration was carried out using a cell unit with ultrafiltration membranes having a nominal cut‐off of 10,000 Dalton. The effects of various experimental factors including the kind and concentration of electrolyte, sample storage, pH. pressure and the preconditioning of the membranes on the speciation analysis of serum copper by ultrafiltration were examined. It was observed that 4.5 ± 2.3% of the total copper in serum was ultrafiltrable and this value did not seem to be influenced by the total serum elemental concentration, the pH (6.5–10) and the pressure (≤ 1.5 kg/cm2). The preconditioning of the ultrafiltration system with 0.1 mol/L calcium nitrate can overcome the adsorption loss of copper effectively, and the addition of tris‐HCl solution (pH 7.4) to serum accelerates the ultrafiltration. The present method was proved to be suitable for speciation analysis for its simplicity, rapidity, small sample requirement and easy control. The results obtained with the method are accurate and reliable.
Catalytic Hydrolysis of Phosphate Diester with Metal Complexes of Macrocyclic Tetraamine in Comicellar Solution
Authors: Xiang Qing‐Xiang , Yu Xiao‐Qi , You Jing‐Song , Yan Qian‐Shun , Xie Rn‐Gang
Published: September 2010

Four novel pyridine or benzene ring‐containing pendant macrocyclic dioxotetraamines 2,6‐dixo‐l,4,7,10‐tetraazacyclododecane ligands have been synthesized. Their metal complexes have been investigated as catalysts for the hydrolysis of bis(p‐nitrophenyl) phosphate (BNPP) in aqueous comicellar solution. The results indicate mat the hydrophobic interaction between substrate and metal complex, the nature of transition metal ion, and the micellar microenvironment are important factors for the hydrolysis of BNPP. Large rate enhancement (up to over two‐three orders of magnitude) employing 5 has been observed.
Syntheses and Properties of New Pendant‐armed Calix[4]arene Derivatives as Cesium Selective Ionophore
Authors: Xing Yan‐Jun , Zhou Zhi‐Xian , Wu Yang‐Jie
Published: September 2010

Two new pendant‐armed calix[4]arene derivatives 5 and 6 have been synthesized. The study of alkali metal picrates extraction indicates that both compounds show preference of cesium cation, compound 6 in 1,3‐alternate conformation has better extractibility for Cs+ than compound 5. The coordination behavior of compound 6 with cesium cation was studied by 1H NMR spectroscopy. The Cs+ selective electrode based on compound 6 exhibits a linear, near Nernstian response characteristics, the slope is 56.4 mV/decade in me concentration range of 10−4—10−1 mol/L, the selectivity coefficient (logKpotCs.Na) is −3.39.
Monobromination of Activated Aromatic Compounds with Polyvinylbenzyltriphenylphosphonium Supported Tribromide
Authors: Wu Ming‐Hu , Yang Gui‐Chun , Chen Zu‐Xing
Published: September 2010

Chloromethylated crosslinked co‐polyvinylbenzene‐divinylbenzene (2% DVB) was treated with triphenylphosphine and then with sodium bromate and hydrobromic add to afford red colored insoluble polyvinylbenzyltriphenylphosphonium supported tribromide. This reagent could be used as a mild and efficient monobrominating reagent for activated aromatic compounds such as phenols, aromatic ethers, aromatic amines and acetylanilines with good yields and high para‐selectivity.
Molecular and Crystal Magnetic Engineering of Polymetallic Coupling System: From Magnetic Molecules to Molecular Magnets
Authors: Cheng Peng , Liao Dai‐Zheng
Published: September 2010

One of the main challenges in the field of molecular materials is the design of molecular ferromagnets. General design strategy includes two steps, that is molecular magnetic engineering and crystal magnetic engineering. The first step is the synthesis of ferromagnetically coupled polymetallic systems. The second step is the assembly of polymetallic systems with muti‐dimensional structure and exhibiting a ferromagnetic transition. This paper summarized the strategies of molecular design and crystal engineering allowed to obtain such systems and our efforts in the fields of molecular magnetism and molecular‐based magnets.
Thermodynamic Calculation in Elimination of Water Pollutants at Hydro‐geo‐chemical Barriers
Authors: Panayotova B. , Velkov M.
Published: September 2010

Thermodynamic saturation coefficients (Ks) and transformation indices (It) can be used to evaluate the possibility of forming hydro‐geo‐chemical precipitation barriers and assess the solid phase (rock) stability in aquifers. Calculations are made on the basis of data on water pH, Eh, conductivity (x) and some relevant ion concentrations. The dependencies of K2 and It on water pH and Eh values can be expressed graphically to estimate the barriers parameters. Barrier generation leads to a decrease in concentrations of pollutants due mainly to precipitation, co‐precipitation and/or sorption processes. Using the diagram Ks, It= f (pH, Eh), supplemented with representative data on concentrations of pollutants before and after the barrier, the elimination and migration of pollutants can be roughly evaluated (predicted) only on the basis of determining pH and Eh values of water and concentrations of ions participating in the barrier formation. The proposed method is applied to assess the migration and elimination of pollutants (U, 226Ra, β‐emitters, SO42) in Bulgarian uranium mine surroundings.
Valence Distributions of Iron and Manganese in Pure, Manganese‐doped and Calcium‐doped Yttrium Orthoferrite
Authors: Cao Xue‐Qiang , Zeng Yue
Published: September 2010

The valence distributions of Fe and Mn in yttrium orthoferrite (YFeO,), YFe0.6Mn0.4O3 and Y0.9Ca0.1Fe0.6Mn0.4O3.8 were studied by the measurement of thermal power. Pure YFeO3 shows the n‐type electrical conductivity associated with small polaron hopping between Fe2+ and Fe3+. Both YFe0.4Mn0.4‐O3 and Y0–9Ca0–1.Fe0–6Mn0–4O3–8 show n‐type and p‐type conductivities at high and low temperatures respectively associated with small polaron hopping between Mn3+ and Mn4+, iron has only oxidation state of Fe3+ and does not have contribution to the electrical conductivity.
Synthesis, Characterization and Magnetic Studies of μ‐Oxamido Copper (II) ‐ Chromium (III) Heterodinuclear Complexes
Authors: Li Yan‐Tuan , Yan Cui‐Wei , Hu Chun‐Xia , Liao Dai‐Zheng
Published: September 2010

Three new μ‐oxamido‐bridged heterodinuclear copper (II)‐chromium (III) complexes formulated [Cu(Me2oxpn)Cr‐(L)2](NO3)3, where Me2oxpn denotes N,N'‐bis(3‐amino‐2, 2‐dimethylpropyl)oxamido dianion and L represents 5‐methyl‐1,10‐phenanthroline (Mephen), 4,7‐diphenyl‐1,10‐phenanthroline (Ph2phen) or 2,2′‐bipyridine (bpy), have been synthesized and characterized by elemental analyses, IR and electronic spectral studies, magnetic moments of room‐temperature and molar conductivity measurements. It is proposed that these complexes have oxamido‐bridged structures consisting of planar copper (II) and octahedral chromium (III) ions. The variable temperature magnetic susceptibilities (4.2–300 K) of complexes [Cu(Me2oxpn)Cr(Ph2phen)2](NO3)3 (1) and [Cu(Me2oxpn)Cr(Mephen)2] (NO3)3 (2) were further measured and studied, demonstrating the ferromagnetic interaction between the adjacent chromium (III) and copper (II) ions through the oxamido‐bridge in both complexes 1 and 2. Based on the spin Hamiltonian, Ĥ = ‐ 2JŜ1 · Ŝ2, the exchange integrals J were evaluated as + 21.5 an−1 for 1 and + 22.8 cm−1 for 2.
Syntheses, Crystal Structures and Cytotoxities of Silver (I) Complexes of 2,2′‐Bipyridines and 1,10‐Phenanthroline
Authors: Zhu Hai‐Liang , Chen Qi , Peng Wen‐Lie , Qi Sui‐Jian , Xu An‐Long , Chen Xiao‐Ming
Published: September 2010

The syntheses, characterizations and in vitro cytotoxities of seven soluble silver (I) compounds (1–7) with 2,2′‐bipyridine (bpy), 5,5′‐dimethyl‐2,2′‐bipyridine (dmbpy) and 1, 10‐phenanthroline (phen) are described. Two of the complexes, [Ag(dmbpy)(NO3)] (1) and [Ag(dmbpy)]ClO4(2), have been structurally established by single‐crystal X‐ray diffraction, which reveals the silver(I) atom in compound 1 is in a Y‐shape coordination geometry with two N atoms (av. AgN = 227.8 pm) from a chelate dmbpy ligand and an O atom (AgO=221.8(4) pm) from a monodentate nitrate. The Ag(I) atom in compound 2 is three‐coordinated by three N atoms, two of which are from a chelate dmbpy, and one from an acetonitrile ligand. The seven compounds showed strong cytotoxities in vitro to both normal and carcinoma cells.
Synthesis of a Cyclic Analogue of Galardin
Authors: Ma Da‐Wei , Wu Wen‐Gen , Qian Jing , Lang Shen‐Hui , Ye Qi‐Zhuang
Published: September 2010

A cyclic analogue 4 of galardin, a known MMP inhibitor, is designed to improve its selectivity. The synthesis of 4 starts from dimethyl (S)‐malate using diaselective alkylation and subsequent cyclization and amide formation as key steps. The compound 4 showed MMP inhibitory activity on all MMPs tested with IC30, ranging from 20.1 μM to 104 μM.
Molecular Design of Calixarene 5. Syntheses and Cation Selectivities of Novel Schiff's Base p‐tert‐Butylcalix[4]arenes
Authors: Liu Yu , Zhao Bang‐Tun , Wang Hao , Chen Qi‐Fa , Zhang Heng‐Yi
Published: September 2010

Five novel Schiff's bases p‐tert‐butylcalix[4]arenes have been synthesized in high yields by the reaction of 1,3‐distally disubstituted p‐tert‐butylcalix[4]arene amine (1) with the corresponding aromatic aldehydes, and their cation binding abilities and selectivities with alkali and heavy metal ions have been evaluated by solvent extraction of aqueous metal picrates to show the highest Ag+ extractability for Schiff's base p‐tert‐butylcalix[4]arene (6) and the best Na+/Li+ and Ag+/Ti+ selectivities for Schiff's base p‐tert‐butylcalix[4]arene (4 and 2) over any other calix[4]arene derivatives, respectively.
Synthesis of p‐tert‐Butyl‐calix[6] ‐biscrown‐3 via Intramolecular Ring‐closure of 1,4‐Bis (2‐(2‐chloroethoxy) ethoxy) ‐p‐tert‐butyl‐calix[6]arene
Authors: Chen Yuan‐Yin , Chen Yi‐Kun , Gong Shu‐Ling , Gao Zu‐Nong
Published: September 2010

With a variation in reaction conditions, 1, 4‐bis (2‐(2‐chloroethoxy)ethoxy)‐calix[6]arene (3) and l,3,5‐tris(2‐(2‐chloroethoxy) ethoxy)‐calix [6] arene (4) or 4 and 4‐chloroethoxyethoxy‐calix[6]crown‐3 (5) were selectively synthesized from p‐tert‐butyl‐calix [6] arene and 2‐(2‐chloroethoxy)ethyltosylate. l,3–4,6‐p‐tert‐butylcalix[6]‐bis‐crown‐3 (6) with (u,u,u,d,d,d) conformation and 1,3–4,5‐p‐tert‐butylcalix[6]‐biscrown‐3 (7) with self‐anchored (u,u, u, u, u, d) conformation were synthesized through an intramolecularly ring‐closing condensation of 1, 4‐bis (2‐(2‐chloroethoxy)ethoxy)‐p‐tert‐butyl‐calix[6]arene (3) in 25% and 15% yield, respectively. Using 5 instead of 3, only 7 was obtained in 65% high yield. 6 and 7 show different complexation properties toward alkali metal and ammonium ions.
Enantioselective Recognition of Calix[4]arene Derivative Bearing Bicyclic Guanidinium forD/LAmino Acid Zwitterions
Authors: Liu Fang , Lu Guo‐Yuan , He Wei‐Jiang , Wang Zhen‐Sheng , Zhu Long‐Gca
Published: September 2010

Thep‐tetra‐tert‐butyl calix[4] arene derivatives (3 and 4) with (5,5) chiral bicyclic guanidinium, as the receptors of amino acid zwitterions, have been synthesizedviaa O‐alkylation reaction ofp‐tetra‐tert‐butyl calix [4] arene with cbJoromethyl chiral bicyclic guanidinium 2 in the presence of anhydrous K2CO3in acetonitrile. The results obtained from liquid‐liquid competitive extraction experiments indicate that the two receptors may selectively recognizeL‐aromatic amino acids, and that the enantioselective recognizability of the receptor 4 with two chiral bicyclic guanidinium units reachs up to about 90% forL‐Phe.
Preparation and Molecular Structure of Binuclear Nickel (I) Complex Bridged by 1,2,4, 5‐Benzenetetracarboxylato Tetravalent Anion
Authors: Cheng Ya‐Qian , Lin Wen‐Jiao , Hu Mao‐Lin , Yuan Ji‐Xin , Wang Shun , Wang Jia‐Guo
Published: September 2010

The title complex [(H2O)2(IMI)3Ni(TCB)Ni(IMI)3‐(H2O)2] H2O (TCB = 1,2,4,5‐benzenetetracarboxylato te‐travalent anion; IMI = imidazole) has been prepared by the reaction of Ni(IMI)3(Ac)2 and TCB in aqueous solution. The crystal structure has been determined by single‐crystal X‐ray diffraction method. It crystallizes in the monoclinic system, space group P21/c(# 14), a = 1.2714(4) nm, b = 0.9411 (3) nm, c = 1.5869(4) nm, β= 108.54(2)°, V= 1.8001(9) nm3, Z = 2. The main feature of the crystal structure is a symmetric binuclear unit made up of two slightly distorted coordination octahedrons, which are bridged by TCB in monodentate fashion to each metal ion. Moreover three nitrogen atoms from three imidazoles, three oxygen atoms from two water molecules and one carboxylate group of TCB coordinated to a nickel (I) ion are found on a face of the octahedron respectively, so the octahedron is a facial isomer.
Catalytic Performance and Characterization of Pt‐Co/Al2O3 Catalysts for CO2 Reforming of CH4 to Synthesis Gas
Authors: Huang Chuan‐Jing , Zheng Xiao‐Ming , Mo Liu‐Ye , Fei Jin‐Hua
Published: September 2010

Pt‐Co/Al2O2 catalyst has been studied for CO2 reforming of CH4 to synthesis gas. It was found that the catalytic performance of me catalyst was sensitive to calcination temperature. When Co/Al2O3 was calcined at 1473 K prior to adding a small amount of Pt to it, the resulting bimetallic catalyst showed high activity, optimal stability and excellent resistance to carbon deposition, which was more effective to the reaction than Co/Al2O3 and Pt/Al2O3 catalysts. At lower metal loading, catalyst activity decreased in the following order: Pt‐Co/ Al2O3 > Pt/Al2O3 > Co/Al2O3. With 9% Co, the Co/Al2O3 calcined at 923 K was also active for CO2 reforming of CH4, however, its carbon formation was much more fast man that of the Pt‐Co/Al2O3 catalyst. The XRD results indicated that Pt species well dispersed over the bimetallic catalyst. Its high dispersion was related to the presence of CoAl2O4, formed during calcining of Co/Al2O3 at high temperature before Pt addition. Promoted by Pt, Co/Al2O4 in the catalyst could be reduced partially even at 923 K, the temperature of pre‐reduction for the reaction, confirmed by TPR. Based on these results, it was considered that the zerovalent platinum with high dispersion over the catalyst surface and the zerovalent cobalt resulting from Co/Al2O4 reduction are responsible for high activity of the Pt‐Co/Al2O3 catalyst, and the remain Co/Al2O4 is beneficial to suppression of carbon deposition over the catalyst.
Study of the Crystal Structure of Oxo‐bridged Binuclear FeIII Complex with Chiral Salen Ligand
Authors: Liu Tao , Ruan Qin‐Xuan , Zhu Zhi‐Ang Wen‐Juan , Chen Yun‐Ti , Chan Albert S. C.
Published: September 2010

A oxo‐bridged binuclear iron complex with chiral salen ligand [Fe2L2]O (H2L = R, R'‐N, N'‐bis (3,5‐di‐tert‐butylsalicylaldene)‐1, 2‐cyclohexanediamine) has been synthesized and the structure has been determined by X‐ray diffraction analysis. The title complex crystallizes in triclinic system with space group P‐1. Crystal data: a = 1.42555(14) nm, b = 1.54889 (15) nm, c = 1.83662 (17) run, = 103.873(2)°, β = 100.506(2)°, 7=101.840(2)°, V = 3.7371 nm3, Dc = 1.082 g/cm3 and Z = 2. In the complex, each iron center is penta‐coordination and in distorted square‐pyramidal environment. Two Fem atoms are intramolecularity bridged by an oxygen atom with Fe‐Fe nonbond distance of 0.3517(3) nm.
Preparation, Crystal Structure and Spectroscopic Studies of Mixed valence Compound [(Cp4i Rh)2 (μ‐Cl)3] [Rh(CO)2Cl2]
Authors: Xu You‐Feng , Pang Zhen , Chen Ming‐Qin
Published: September 2010

[(Cp4i Rh)2(μ‐Cl)3] [Rh(CO)2Cl2] (Cp4i = tetraisopropyl‐cyclopenta‐dienyl) has been prepared and its crystal is in the space group of Pbar with a= 0.9417 (8), b = 1.4806 (3), c = 1.5062 (2) nm, a = 92.980(10), β = 97.42(3), γ = 93.98 (3)°, V = 2.0735(18) nm3 and Z = 2. The crystal structure consists of a cation of [(η5‐Cp4i) Rh (III)(μ‐Cl)3 Rh (III) (η5‐Cp4i)]+ and an anion of [Rh (I) (CO)2 Cl2]. The two bulky tetraisopropylcyclopentadienyl ligands are in the ecliptic conformation with angle of 10.19° between two cyclopentadienyl ring planes.
Several Organic Salts with High Two‐Photon Active
Authors: Tian Yu‐Peng , Yu Wen‐Tao , Fang Qi , Jiang Min‐Hua , Wang He‐Zhou
Published: September 2010

Several organic salts with D‐A molecular structure and different counterion have been prepared and experimentally investigated. The two‐photon induced frequency‐upconverted spectra and two‐photon pumped lasing are measured for the organic salt solutions in various solvents. The results indicate that counterions have influence on their stability and lasing property.
A Novel Conversion of 2, 4‐Diaryl‐2, 3‐dihydro‐1 H‐1, 5‐benzodiazepines into 2, 4‐Diaryl‐3 H‐1, 5‐benzodiazepines
Authors: Zhang Qi‐Han , Xu Jia‐Xi
Published: September 2010

A novel conversion of 2, 4‐diaryl‐2, 3‐dihydro‐1 H‐1, 5‐benzodiazepins into 2, 4‐diaryl‐3 H‐1, 5‐benzodiazepines by the reaction with m‐chloroperbenzoic acid (MCPBA) was reported.
Synthesis of Titanium (IV) Complexes with Schiff‐base Ligand and Their Catalytic Activities for Polymerization of Ethylene and Styrene
Authors: Yong Li , Huang Ji‐Ling , Lian Bing , Yan ‐Long Qian
Published: September 2010

Reaction of titanium (IV) isopropoxide with the unusual land of Shiff‐base in 1:1 molar ratio gives a variety of new derivatives of titanium (IV) in high yield. These complexes were characterized by elemental analyses, IR, MS and 1H NMR. It was noteworthy to find that all these complexes were active for polymerizations of ethylene and styrene when activated by a Lewis acid cocatalyst (MAO).
Molecular Structures of Dibromo[(E)2‐bromo‐2‐phenylvinyl]‐(phenyl) tellurium (IV) and Dibromo [(Z)‐2‐bromo‐2‐phenyl‐vinyl] (p‐tulyl) tellurium (IV) hydrate methanolate
Authors: Lu Wei‐Min , Wang Ya‐Pin , Huang Xian , Sun Jie
Published: September 2010

The structures of title compounds, [TeBr2(C8H6Br)(C6H5)] (I) and [TeBr2(C8H6Br)(C7H9)](H2O)(CT3OH) (II), have been determined by X‐ray diffraction. The structures confirm that E‐ or Z‐type configuration of vinylic telluride depends on the polarity of solvent employed. In either structure, Te atom is in a trigonal dipyramide configuration with the lone pair of electrons in the equatorial position.
Zinc Transfer Kinetics of Metallothioneins and Their Fragments with Apo‐carbonic Anhydrase
Authors: Huang Zhong‐Xian , Liu Fang , Zheng Qi , Yu Wen‐Hao
Published: September 2010

The zinc transfer reactions from Zn7‐MT‐I, Zn7‐MT‐II, Zn4‐α fragment (MT‐I) and Zn4,‐α fragment (MT‐II) to apo‐carbonic anhydrase have been studied. In each reaction, no more than one zinc ion per molecule is involved in metal transfer. Zn7‐MT‐I and Zn7‐MT‐II donate zinc to apo‐carbonic anhydrase andde novoconstitute it at a comparable efficiency, while Zn7‐MT‐II exhibits a little faster rate. Surprisingly, Zinc is released from Zn4‐α fragment (MT‐II) with a much faster rate than from Zn4‐α fragment (MT‐I), whose rate is close to that of Zn7‐MT‐I. The reason for the difference is still unknown. Introducing complex compounds into this system may give rise to an effect on the reaction. The transfer from Zn7‐MT‐II in the presence of reduced glutathione shows little difference compare to the control, suggesting that the reduced glutathione is not involved in zinc transfer process. However, glutathione disulfide does accelerate this zinc transfer reaction remarkably, indicating that the oxidative factors contribute to zinc release from metallothioneins.
A Study on Some Copper (II) Complexes of Polyaza Cryptands and Planar Macrocycles—Synthesis, Characterization and Superoxide Dismutase Activity
Authors: Gao You‐Liang , Shen Cheng‐Yu , Tang Yin‐Yan , Luo Qin‐Hui , Yu Shu‐Yan
Published: September 2010

Two kinds of macrocyclic copper(II) complexes were synthesized. One of them is composed of copper(II) cryptates of ligands L1‐L4 which are condensation products of 5‐R‐2‐methoxy‐1,3‐phenyldialdehyde (R=OCH3, L1) with tris(2‐aminoethyl) amine and 5‐R‐2‐methothoxy‐1, 3‐phenyldialdehyde (R= CH3, L3) with tris(2‐aminopropyl)amine as well as their reduced products of L1 and L3 (L2 and L4). The other is composed of two‐dimensional macrocyclic copper(II) complexes of ligands L5‐L8 of condensation products of diethylene triamine with 4‐R‐l‐methoxy‐2,6‐phenyldialdehyde (R= Cl, Br. CH3, OCH3). The relationship between their structures and superoxide dismutase (SOD) activity was investigated. The results can provide some clues to the synthesis of SOD mimics.
Synthesis and Magnetic Studies of Copper (II)‐Manganese (II) Heterobinuclear Complexes with an Oxamido Bridge
Authors: Li Yan‐Tuan , Zhu Xue‐Dong , Yan Cui‐Wei , Liao Dai‐Zheng
Published: September 2010

Four new copper (II)‐manganese (II) heterobinuclear complexes bridged byN, N'‐bis[2‐(dimethylamino)ethyl)]oxamido dianion (dmoxæ) and end‐capped with 1, 10‐phenanthroline (phen), 5‐methyl‐1, 10‐phenanthroline (Mephen), diaminoethane (en) or 1,3‐di‐aminopropane (pn). respectively, namely, [Cu(dmoxae)MnL2] (CIO4)2 (L=phen, Mephen, en, pn), have been synthesized and characterized by elemental analyses, IR, electronic spectral studies, and molar conductivity measurements. The electronic reflectance spectrum indicates the presence of spin exchange‐coupling interaction between bridged copper(II) and manganese (II) ions. The cryomagnetic measurements (4.2‐300 K) of [Cu(dmoxae)Mn(phen)2](CIO4)2 (1) and [Cu(dmoxae)Mn(Mephen)2](CIO4)2(2) complexes demonstrated an antiferromagnetic interaction between the adjacent manganese(II) and copper (II) ions through the oxamido‐bridge within each molecule. On the basis of spin Hamiltonian, H= ‐ 2JS1. S2. the magnetic analysis was carried out for the two complexes and the spin‐coupling constant (J) was evaluated as −35.9 cm−1 for 1 and ‐ 32.6 cm−1 for 2. The influence of methyl substitutions in the amine groups of the bridging ligand on magnetic interactions between the metal ions of this kind of complexes is also discussed.
Intermolecular Heterocoupling Reaction between N‐Sulfonylimines and Aliphatic Ketones Promoted by Samarium (II) Iodide
Authors: Liu Yun‐Kui , Zhang Yong‐Min , Liu Xi
Published: September 2010

N‐sulfonylimines (1) were induced by samarium(II) iodide to produce radical anion intermediates (2) in situ, which were trapped by aliphatic ketones (4) to afford heterocoupling products β‐sulfonamido alcohols (5) in moderate to good yields under mild and neutral conditions.