bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparison study of several numerical integration schemes used in calculations of density functional theory,
Authors: Gong‐Yi Hong , Le‐Min Li
Published: September 2010

Several numerical integration schemes for the evaluation of matrix elements in density functional theory calculations have been studied and compared by computational practice. The best scheme was found to be the combination of the atomic partition [function proposed by Becke with the scaled generalized Gauss‐Laguerre quadrature formula for radial integration suggested by Yang, which achieve the highest convergence rate to the numerical integration. With the same number of integration points, the accuracy of the calculated results by this scheme is higher by 1 to 2 orders of magnitudes than that by other schemes. The reason for achieving higher accuracy by this scheme has been proposed preliminarily.
Fluorescence quenching of eosin upon adsorption by colloidal silver mediated in aqueous solution and reverse Micelles
Authors: Ling Zang , Tao Shen
Published: September 2010

The optical effects of the adsorption of eosin on the colloidal silver particle have been investigated in aqueous solutions. It was found that upon adsorption the fluorescence of eosin was effectively quenched. This was explained as the photoinduced interfacial electron transfer from the excited singlet state of eosin to the silver particle. Decreasing pH of the solution favors the adsorption of eosin and so enhances the fluorescence quenching. For comparison, the fluorescence quenching in reverse micelles was also investigated. The quenching behavior was much different from that mediated in aqueous solution. This was attributed to the unique microenvironment of reverse micelles.
Computer‐assisted optimization of mobile phase compositions and development distance selectivity in gradient two‐step development high‐performance thin‐layer chromatography
Authors: Bing‐Wen Yan , Ling Zhang , Qin‐Sun Wang
Published: September 2010

A computer‐assisted method is presented for optimization of mobile phase compositions and development distance in gradient two‐step development HPTLC. The method is based on a system which can predict the final Rf values for gradient two‐step development from values measured using five preliminary runs. The statistical scanning method is then used for optimization, using Rf difference as the selection criterion. The method was evaluated using a mixture of eight components. Excellent agreement was obtained between predicted and experimental results.
Semiempirical prediction of the hyperpolarizabilities for cyanovinyl‐substituted donor‐acceptor molecules
Authors: Cun‐Yuan Zhao , Yong Zhang , Wei‐Hai Fang , Xiao‐Zeng You
Published: September 2010

We present here a systematically theoretical study on the nonlinearities and their structure‐property relationship of cyanovinyl‐substituted donor‐acceptor molecules by virtue of semiempirical PM3/AM1‐FF approach. Good consistency between measured and calculated hyperpolarizabilities is obtained. Results show that conformation has a significant effect on hyperpolarizabilities. The torsion angle change between two conjugated parts of the molecular systems can substantially alter the nonlinearities. The total amount of charge transfer difference from donor to acceptor has been introduced to understand the microscopic nature of the nonlinear optical properties for the title molecules. General guidelines may be sought out in the search of molecules with large values of β. Some molecules with large molecular hyperpolarizabilities can be predicted by the optimization for the longer δ‐electron systems with both acceptor and donor groups.
Luminescent properties of Ba3(PO4)2:Eu, Tb phosphors
Authors: Yong Gao , Chun‐Shan Shi
Published: September 2010

Luminescence of europium (III), europium(II) and terbium(III) has been observed in Ba3(PO4)2:Eu, Tb phosphors which are synthesized in air atmosphere. The valence state of europium is influenced by amount of terbium. It is notable that the relative intensity of the emission spectra peaks corresponding to Eu2+ is increased if the amount of Tb3+ is increased. These phenomena can be explained by an electron transfer mechanism. We predict a new kind of two‐rare‐earth codoped trichromatic phosphors in Ba3(PO4)2 matrix.
A novel solid state Michael addition reaction of N‐heterocyclic compounds containing active C—H bond
Authors: Xiao‐Lu Li , Yong‐Mei Wang , Bing Tian , Ji‐Ben Meng
Published: September 2010

In this paper, a novel solid state Michael‐type addition reaction of N‐heterocyclic compounds containing the active‐CH group was investigated. 3‐Methyl‐l‐phenyl‐5‐pyrazolone (MPP) and indole (In) reacted with 4‐arylmethylene‐3‐methyl‐l‐phenyl‐5‐pyrazolone (1) in the solid state at room temperature to give the corresponding adducts, aryl‐4,4′‐bis(5‐hydroxy‐3‐methyl‐l‐phenylpyrazolyl) methane (2a—n) and l‐aryl‐l‐(5′‐hydroxy‐3′‐methyl‐L'‐phenyl‐4′‐pyrazolyl)‐l‐(3′‐indolyl) methane (Sa—n), respectively. This is a feasible method for preparing the compound which contains two heterocyclic groups on the same carbon.
Studies on the reaction of 3‐substituted‐4‐hydroxy‐2H‐1,2‐benzothiazine 1,1‐dioxides with aryl isocyanates and the synthesis of corresponding derivatives
Authors: Guo‐Feng Zhao , Hua‐Zheng Yang
Published: September 2010

The reaction of 3‐substituted‐4‐hydroxy‐2H‐l,2‐benzothiazine 1,1‐dioxides with aryl isocyanate under different equivalents of strong base NaH was studied. Seventeen of new derivatives were obtained whose structures were characterized by 1H NMR, IR, MS, elementary analysis and FeCl3 test.
Study on thermal stability of poled non‐linear optical polymers
Authors: Yu‐Quan Shen , Yu‐Chun Yang , Ling Qiu , Xing‐Fa Fu , Shang‐Xian Yu , Jiang‐Nan Gu , G.R. Möhlmann , C.P.J.M. Van Der Vorst
Published: September 2010

A logarithmic expression is proposed to describe relaxation of the polar order in side chain polymers, together with a new way of plotting temperature dependent relaxation data. This results in a straight line extending even below the glass transition temperature in the case of poled nonlinear optics (NLO) side chain polymers. A simple procedure to determine the rotational diffusion constant Dr is given and Dr values of several polymer systems have been evaluated and compared with each other. It appears that, starting from the conventional and well known poled polymer system currently applied, a further lowering of Dr by about 3 orders of magnitude is necessary in order to reach an acceptable orientational stability or lifetime of poled polymers for practical applications. Attempts have been made to introduce electron push‐pull substituents into high thermostable molecular frameworks and results of preliminary measurements are reported.
In‐situ FTIR studies of dimethyl ether adsorption on H‐ZSM‐5 zeolites
Authors: Xuan‐Zhen Jiang
Published: September 2010

In situ infrared spectra of dimethyl ether adsorbed on two H‐ZSM‐5 zeolites are reported which are different in both lattice and extraframework aluminium contents. A number of dissociatively adsorbed dimethyl ether species associated respectively with the Bronsted acid sites, the external silanol groups and extraframework aluminium species at different temperatures are identified. In particular, dimethyl ether reacts with non acidic hydroxyl species associated with extraframework aluminium to form the third methoxy species. The distributions of hydrocarbons desorbed from a single pulse of dimethyl ether (1.0 mL) onto these zeolite samples are presented. Propene is the major product, and the yield of hydrocarbons correlates with the concentration of Bronsted acid bound methoxy groups.
The synthesis and fluorescence of a methoxy‐phenyl substituted C60‐pyrrolidine derivative
Authors: Zhou De‐Jian , Gan Liang‐Bing , Luo Chu‐Ping , Huang Chun‐Hui , Yao Guang‐Qing
Published: September 2010

A new 4‐methoxyphenyl substituted C60‐pyrrolidine derivative, C60(C10H13NO) (1), was prepared and its room‐temperature fluorescence waa studied. Its fluorescence intensity is three times stronger than that of C60. Its singlet energy was estimated to be 25 kJ/mol lower than that of C60. The fluorescence lifetime was determined to be 2.1±0.3 ns by using the frequency domain method. The fluorescence quenching by concentration and aromatic electron donor: N, N‐dimethyl aniline (DMA) wan investigated. Data show that its fluorescence could not be quenched by DMA.
Luminescence of RE3+ and energy transfer from Gd3+ to RE3+ (RE = Dy, Eu) in SrGdAlO4:RE3+
Authors: Liu Sheng‐Li , Su Qiang
Published: September 2010

Spectral properties of Gd3+, Dy3+ and Eu3+ ions in SrGdAlO4 are reported in detail.

A cooperativ vibronic transition of Gd3+ and the emission from the higher 5DJ (J=1, 2, 3) levels of Eu3+ were observed. Energy transfer occurs from Gd3+ to Dy3+ and to Eu3+. The influence of Gd3+ and Dy3+ concentrations on the luminescence intensity is discussed.
A two‐step approach to 2‐polyfluoroalkyl quinolines from N‐aryl polyfluoroalkyl imidoyl iodides
Authors: Yu Hong‐Bin , Zhang Qi‐Sheng , Huang Wei‐Yuan
Published: September 2010

2‐Polyfluoroalkyl quinoline derivatives were synthesized from the enaminones which were obtained from the reaction of N‐aryl polyfluoroalkyl imidoyl iodides with methyl ketones.
Synthesis and crystal structure of an ionic cluster {[Mo3(μ3‐O)(μ‐S)3(dtp)3(py)3][CdI(dtp)2]}
Authors: Lu Shao‐Fang , Huang Jian‐Quan , Huang Xiao‐Ying , Wu Qiang‐Jin
Published: September 2010

A new cluster compound {[Mo3(μ3‐O)(μ‐S)3(dtp)3(py)3][CdI(dtp)2]} (dtp=S2P(O‐C2H5)−2) was obtained from the reaction of [Mo3OS3(dtp)4(H2O)] with a CdI2‐Bu4NI mixture. The molecular structure is composed of a cluster cation [Mo3OS3(dtp)3(py)3]+ and the complex anion [CdI(dtp)2]−. Crystal data: Triclinic, space group P1 with cell parameters a=1.4672(7), b=1.5356(5), c= 1.6806(5) nm, α=74.59(3), β=67.89(4), γ=78.86(3)°, V=3.364(2) nm3, and Z=2, least‐squares refinement of 8941 reflections gives a final agreement factor of R=0.052, Rw=0.065.
Theoretical studies on the mechanism of α‐hydroxy‐acid gas‐phase elimination process and its substituent effect
Authors: Song Wei‐Ping , He Shao‐Ren , Fu Xiao‐Yuan
Published: September 2010

The α‐hydroxy‐acid gas‐phase elimination process has been studied theoretically by HF/3‐21G. The calculated results can be summed up as follows: (1) The elimination process is a stepwise reaction. In the first step, a membered ring intermediate is formed via a 5‐membered ring transition state; while the product is formed in the second step via a 3‐membered ring transition state. (2) The obtained results of the substituent effect show that the increase of electronic donation of the alkyl groups is favorable for the reaction. Other substituents which show the electron‐withdrawing inductive effect (e.g. Cl, CN, CF3) are unfavorable for this process.
Fluorescence quenching of para‐substituted styrenes by tetramethylethylene. Correlation analysis of the quenching coefficient KSV and the quenching rate constant kq by the dual‐parameter equation with polar and spin‐delocalization substituent constants
Authors: Zhang Yu‐Huang , Jiang Bin , Jiang Xi‐Kui
Published: September 2010

The fluorescence quenching coefficient (KSV) and the quenching rate constant kq of ten para‐substituted styrenes (1‐Ys) have been measured and correlation‐analyzed by both the dual‐parameter equation (Eq. 1) with (ρxσx + ρ· σ·) and the single‐parameter equation (Eq. 2) with ρxσx. Excellent results have been obtained for the correlation of KSV against (ρxσmb + ρ· σ·JJ) or (ρxσ+ + ρ· σ·JJ ). Our results suggest that, possibly, there might be no need to use excited‐state substituent constant for the fluorescence quenching process of excited states of styrenes.
NMR study on solubility of benzyl alcohol and its transfer free energy from D2O to cationic micelle
Authors: Shen Qiang , Li Gan‐Zuo , Ma Cheng‐Song , Hao Shu‐Xuan , Wei Xi‐Lian , Huang Yan‐Zhang
Published: September 2010

A new kind of surfactant, [CnH2n+1 OCH2CH(OH)CH2N(CH3)3]Cl (n=12, 14, 16) was synthesized. The solubility of benzyl alcohol in micellar solutions was determined by 1H NMR method. The results indicate that the length of alkyl chains of surfactant affects the solubility of benzyl alcohol in 2.5 × 10−2 mol/L micellar solutions. The solubility of benzyl alcohol per liter of micellar solution is 0.095 mole for n=12, 0.115 mole for n=14, 0.165 mole for n=16. The transfer free energy of benzyl alcohol from aqueous phase to micellar phase is −24.29 kJ/mol for n=12, −24.37 kJ/mol for n=14, −24.49 kJ/mol for n=16.
Synthesis and characterization of μ‐oxamido copper(II)‐iron(II) heterobinuclear complexes with an antiferromagnetic exchange interaction
Authors: Yan Cui‐Wei , Li Yan‐Tuan , Liao Dai‐Zheng
Published: September 2010

Four new μ‐oxamido heterobinuclear complexes have been synthesized and identified as [Cu(oxap)Fe(L)2]SO4, where oxap denotes the N, N'‐bis(2‐aminopropyl)oxamido dianion and L represents diaminoethane (en); 1,3‐diaminopropane (pn); 1,2‐diaminopropane (ap) and 2,9‐dimethyl‐l,10‐phenanthroline (Me2‐phen). Based on the elemental analyses, spectroscopic studies, magnetic moments (at room temperature) and molar conductivity measurements, extended oxamido‐bridged structures consisting of a copper(II) and an iron(II) ions, which have a square planar environment and an octahedral environment, respectively, are proposed for these complexes. Complexes [Cu(oxap)Fe(en)2]SO4 (1) and [Cu(oxap)Fe(pn)2]SO4 (2) have been characterized by variable temperature magnetic susceptibility (4.2∼'300 K) and the observed data were least‐squares fitted to the susceptibility equation derived from the spin Hamiltonian including single‐ion aero‐field interaction for the iron(II) ion, H=−2JŜ1 ·;Ŝ2—DŜ2zl, giving the exchange integrals J=−21.9 cm−1 for 1 and J=−23.6 cm−1 for 2. These results are commensurate with antiferromagnetic interactions between adjacent metal ions within each molecule.
Regioselective addtion of 5‐amino‐3‐benzylthio‐1,2,4‐triazole and its analogues with aryl isocyanates
Authors: Lu Rong‐Jian , Qian Bao‐Ying , Deng Hai‐Yan , Yang Hua‐Zheng
Published: September 2010

The orientation of the addition of 5‐amino‐3‐benzylthio‐1,2,4‐triazole and its analogues (pyrazole) (1) with the aryl isocyanate can be directed by controlling the reaction temperature and one of the product, 5‐amino‐1‐arylaminocarbonyl‐3‐benzylthio‐1,2,4‐triazole (pyrazole) (2), can rearrange at 170°C to another product, 5‐arylureylene‐3‐benzylthio‐1,2,4‐triazole (pyrazole) (3). A plausible mechanism explanation for this rearrangement reaction was presented. It was suggested that the rearrangement reaction could be referred to the thermodynamics transposition leading to the predominant 5‐arylureylene‐3‐benzylthio‐1,2,4‐triazole energy preferentially.
Bioreduction of quinone derivatives by immobilized Baker's yeast in hexane
Authors: Lian‐Quam Gu , Hai‐Feng Wei , Xiao‐Chun Zhang , Gui Xu , Lin Ma
Published: September 2010

Immobilization techniques and biocatalytic transformations performed in organic media are new developing methods for organic reactions. Baker's yeast was immobilized on the alginate supports. This preparation contained about 20% of dry yeast cells. The immobilized Baker's yeast were found to be very effective in the reduction of O‐benzoquinone, p‐benzoquinones, naphthoquinones, and anthraquinones in hexane.
Study on the syntheses of new 1‐o‐chlorobenzoyl‐3‐(5′‐substituted phenylamino‐6′‐phenyl)‐1′,2′,4′‐triazinyl ureas
Authors: Jian‐Ping Zou , Run‐Sheng Zeng , Ai‐Fen Wang , Zhong‐E Lu
Published: September 2010

Eight new l‐o‐chlorobenzoyl‐3‐(5′‐substituted phenylamino‐6′‐phenyl)‐1′,2′,4′‐triazinyl ureas (5a–h) have been synthesized and their bioactivities were detected.
Synthesis of propyl O‐(α‐L‐rhamnopyranosyl)‐(1→3)‐[2,4‐di‐O‐(2s‐methylbutyryl)‐α‐L‐rhamnopyranosyl]‐(1→2)=(3‐O‐acetyl‐β‐D‐glucopyranosyl)‐(1→2)‐βp‐D‐fucopyranoside, the tetrasaccharide moiety of Tricolorin A
Authors: Shou‐F'U Lu , Qin‐Qin Ouyang , Zhong‐Wu Guo , Biao W , Yong‐Zheng Hui
Published: September 2010

Propyl O‐(α‐L‐rhamnopyranosyl)‐(1→3)‐[2,4di‐O‐(2s‐methylbutyryl)‐α‐L‐rhamnopyranosyl]‐(1→2)‐(3‐O‐acetyl‐β‐glucopyranosyl)‐(1→2)‐β‐D‐fucopyranoside (1), the tetrasaccharide moiety of Ricolorin A, was synthesized in total 23 steps with a longest linear sequence of 10 steps, and overall yield of 3.7% from D‐Glucose. The isomerization of the dioxolane‐type benzylidene in the prance of NIS/AgOTf was observed. Tetrasaccharide 1 exhibited no activity against the cultured P388 cell as Tricolorin A did.
Synthesis and photophysical properties of porphyrin‐phthalocyanine heterodimer linked by piperazine
Authors: Xi‐You Li , Qing‐Fu Zhou , Hong‐Jian Tian , Hui‐Jun Xu
Published: September 2010

A porphyrin‐phthalocyanine heterodimer linked by piperazine has been synthesized and characterized by spectroscopic methods. UV‐visible absorption spectra indicated the presence of weak intramolecular interaction between the two chromophores. Selective excitation of the porphyrin moiety leads to energy transfer process to the phthalocyanine subunit. Furthermore, on the bases of the solvent‐dependent fluorescence data, a competing electron transfer reaction is shown to occur in this heterodimer. The efficiency of both photophysical processes depends strongly on solvent polarity and is related to the separation distance of the two chromophores and their relative orientation. The value of ΔG obtained using the Rehm‐Weller equation clearly indicates that the heterodimer exists preferably in the “boat form” upon excitation in good agreement with the experimental results of co‐occurence of energy and electron transfer process observed for the heterodimer.
5‐Fluorouracil derivatives XXIII. Synthesis and antitumor activities of 1‐carbamoyl‐5‐fluorouracils having aromatic ring
Authors: Shoichiro Ozaki , Xiang‐Zheng Kong , Yutaka Watanabe , Tomonori Hoshiko , Tomio Ogasawara , Takao Ueno , Uiroyuki Furukawa , Masaaki Iigo , Akio Hoshi
Published: September 2010

In order to get good antitumor agents especially better than 5‐fluorouracil, tegafur and l‐hexylcarbamoyl‐5‐fluorouracil (HCFU), fourty nine 1‐carbamoyl‐5‐fluorouracil having aromatic ring were synthesized from 5‐fluorouracil and isocyanates or mines. Antitumor activity was tested in the L1210 tumor system, and 5 compounds gave better value of therapeutic ratio than 5‐fluorouracil, tegafur, HCFU. 1‐(4‐Methoxybenzylcarbamoyl)‐5‐fluorouracil gave the best result.
Parallel and serial dual electrode detectors for capillary electrophoresis
Authors: Jian‐Nong Ye , Xue‐Wei Zhao , Yu‐Zhi Fang , Richard P. Baldwin
Published: September 2010

Application of parallel and serial dual electrode detectors for capillary electrophoresis was first described. In parallel dual electrode approach, two 100 μm‐diameter Cu disks arranged side by side were used as the dual working electrode for the simultaneous determination of a mixture of carbohydrates and amino acids. In serial dual electrode approach, two working electrodes were arranged in a disk‐ring manner for the simultaneous determination of both cysteine and cystine; the disk electrode was Hg/Au serving as the upstream electrode, the ring electrode was 5% CoPC carbon paste serving aa the downstream electrode.
Kinetic studies on the aggregation behavior of phosphatidylcholines and their analogs
Authors: Guo‐Zhen Ji , Ya‐Qiu Long , Xi‐Kui Jiang
Published: September 2010

Phosphatidylcholines (Ln's) and their neutral analogs 1,2‐diacyl‐sn‐glycerol‐3‐phosphoric acid bromoethyl esters (Pn's) have been found to exhibit different aggregation behaviors brought about by hydrophobic‐lipophilic interactions (HLI) by means of kinetic probe in MeOH‐H2O binary aquiorganic systems. The effects of the structure and the environment on the interesting aggregation of the amphiphilic molecules are discussed.
Preparation and reaction of bis (perfluoroalkanesulfonyl)methyl halides
Authors: Shi‐Zheng Zhu , Guo‐Lin Xu , Chao‐Yue Qin , Yong Xu , Qian‐Lk Chu
Published: September 2010

Halogenation of the potassium or silver salts of bis(trifluoromethanesulfonyl)methane (CF3SO2)2CH2 and its cyclo analogues 1 with N‐fluoro‐bis(trifluoromethanesulfonyl)imine [(CF3SO3)2NF], chlorine or bromine gave good yields of the corresponding α‐halo disulfone (CF3SO2)2CHX and cyclo analogues 9, 10. The chemical transformation of these fluorinated α‐halo‐disulfones are described.
Quantum chemical studies on the structures, properties and decomposition of the azido derivatives of trinitrobenzenes
Authors: Xue‐Dong Gong , He‐Ming Xiao , Hai‐Shan Dong
Published: September 2010

The geometries, heats of formation and electronic structures of 15 azido‐derivatives of 1,2,3‐TNB (I), 1,2,4‐TNB (II) and 1,3,5‐TNB (III) have been studied using quantum chemical AM1 method at HF level. The effect of azido substitution on the structures and properties of TNBs has been discussed and the relative stability of the title compounds has been established. The processes of the decomposition of the title compounds by breaking C‐NO2, C‐N3 and CN‐N2 bonds are investigated at UHF‐AM1 level. It is shown that the decomposition of the title compounds may be initiated by the cleavage of both C‐NO2 and N‐N2 bonds.
Stereospecific hydrohalogenation reactions of electron‐deficient alkynes
Authors: Xi‐Yan Lu , Sheng‐Ming Ma
Published: September 2010

Stereospecific hydrohalogenation reactions of electron‐deficient alkynes, i.e., 2‐alkynoic acids, 2‐alkynoates, 2‐propynamides, 2‐propynenitrile, 1‐alkynyl phosphonates/phosphine oxides, 1‐alkynyl sulfoxides/triflones, and 1‐alkynyl iodonium salts with lithium or sodium halides to afford Z‐alkenyl derivatives and their applications in synthesis of important intermediates as well as natural products were reviewed.
Density of supercritical CO2‐tetrahydrofuran binary mixture and the partial molar volume of the cosolvent
Authors: Qun Xu , Bu‐Xing Han , Hai‐Ke Yan
Published: September 2010

The densities of supercritical CO2‐tetrahydrofuran (cosolvent) binary mixture were measured at temperatures in range of 308.15 to 323.15 K and at pressure up to 16.5 MPa. The concentrations of tetrahydrofuran were from 0 to 0.57 mol/L. The partial molar volume of tetrahydrofuran was calculated based on the relationship between the density of the mixture and the concentration of the cosolvent. It is observed that the partial molar volume of the cosolvent is negative and the absolute value decreases with increasing pressure and the concentration of the cosolvent.
Application of organic selenides and tellurides in organic synthesis
Authors: Xian Huang , Yun Ma
Published: September 2010

This paper describes the progress on the synthesis of organic selenides and tellurides and their application in organic synthesis. Low dent selenium and telluronium compounds having high reducing selectivity can be used to form carbon‐hydrogen bonds an special reducing reagents. Telluronium ylides can react with aldehydes and ketones by Wittig‐type condensation to produce (E)‐configuration alkenes stereoselectively. α‐Phenylselanyl arsonium ylides were prepared by transylidation reaction of arsonium ylides with phenylselanyl halides which can undergo Wittig‐type reactions with carbonyl compounds to give (Z)‐α‐selanyl‐α,β‐unsaturated compounds with high stereoselectivity. Zirconium, tin, boron, halogen, metal or hetero‐atom were introduced in organoselenium and telluronium compounds an new difunctional group reagents. Under transition metal catalysis, the corresponding cross coupling reactions provide new methods of formation of carbon‐carbon double bonds, which were used in the stereoselective synthesis of the alkenes.
Chemical behaviours of 3‐[1′‐chloro‐3′‐(2″‐phenyl‐1″,3″‐oxazol‐5″‐one=4″‐ylidene)propen‐1′‐yl]coumarin towards some nucleophilic reagents
Authors: Mohey El‐Deen, Ibrahim
Published: September 2010

The chemical behaviours of 3‐[1′‐chloro‐3′‐(2″‐phenyl‐1″,3″‐oxasol‐5″‐one‐4″‐ylidene)‐propen‐1′‐yl]coumarin towards nucleophilic reagents (such as hydrolysis, aminolysis, hydroxyl‐aminolysis, methanolysis and hydrazinolysis) were described.
Application of samarium reagents in organic synthesis
Authors: Yu Ming‐Xin , Zhang Yong‐Min , Bao Wei‐Liang
Published: September 2010

Application of samarium diiodide, samarium triiodide, Sm0/auxiliary system and organosamarium reagents in organic synthesis was reviewed.
Synthesis of heterocyclic compounds from 2‐phenyl‐1,2,3‐triazole‐4‐formylhydrazine
Authors: Liu Fang‐Ming , Yu Jian‐Xin , Lu Wen‐Jie , Liu Gang , Liu Yu‐Ting , Chen Yao‐Zu
Published: September 2010

2‐Phenyl‐1, 2, 3‐triazole‐4‐formylhydrazine (2) was prepared by hydrazinolysis of the corresponding ester 1. Reaction of 2 with CS2/KOH gave the oxadiazole derivatives (3) which via Mannich reaction with different dialkyl amines furnished 3‐N, N‐dialkyl derivatives (4a–c). Also, condensation of 2 with appropriate aromatic acid in POCI3 yielded oxadiazole derivatives (5a–c), or with aldehydes and ketones afforded hydrazones (6a–c). Cyclization of (6a–c) with acetic anhydride gave the desired dihydroxadiazole derivatives (7a–c). On the other hand, reaction of dithiocarbazate (8) with hydrazine hydrate gave the corresponding triazole derivative (9) which on treatment with carboxylic acids in refluxing POCI3 yielded s‐triazole [3, 4–b]‐1, 3, 4‐thiadiazole derivatives (10a–b). The structures of all the above compounds were confirmed by means of IR, 1H NMR, MS and elemental analysis.
Synthesis and mesomorphic properties of trifluorobenzoate liquid crystal
Authors: Yang Yong‐Gang , Wen Jian‐Xun
Published: September 2010

Four series of trifluorobenzoate liquid crystals have been synthesized. Their phase transition temperatures have been also measured by texture observation in a polarizing microscope and confirmed by DSC. The influence of the lateral fluoro‐substitution and triple bond has been also discussed.
A new procedure to enols of 2‐acylmethyl‐4, 4‐dimethyl‐2‐oxazolines under ultrasonically dispersed potassium system
Authors: Chen Xu , Wang Xiao‐Lun , Lian Hong‐Zheng , Chen Ji‐Jun , Pan Yi , Shi Yao‐Zeng
Published: September 2010

Various enols of 2‐acylmethyl‐4, 4‐dimethyl‐2‐oxazolines were prepared in moderate yields via ultrasonically catalyzed reactions of 2, 4, 4‐trimethyl‐2‐oxazoline with arenecarboxylic esters in the presence of UDP‐t‐BuCl‐i‐Pr2NH system.
Cycloaddition of benzoheteroazepine II Reactions and conformations of cycloadducts on 1, 5‐benzothiazepines and 1,5‐benzodiazepines with nitrile imine and nitrile oxides
Authors: Xu Jia‐Xi , Wu Hai‐Tao , Jin Sheng
Published: September 2010

Benzodiazepine and benzothiazepine derivatives have been well known as therapeutically important compounds. Four new tricyclic heterocyclic compounds, 3a, 4, 5, 11‐tetrahydro‐3H‐l,2, 4‐triazalo [4, 3‐d] [1, 5] benzothiazepines (3), 3a, 4, 5, 11‐tetrahydro‐3H,6H‐1, 2, 4‐triazolo[4, 3‐d] [1, 5]benzodiazepine (4), 3a, 4, 5, 11‐tetrahydro‐1, 2, 4‐oxadiazolo [4, 5‐d] [1, 5]benzothiazepines (5, 6) and 3a,4, 5, 11‐tetrahydro‐6H‐1, 2, 4‐oxadiazolo[4, 5‐d] [1, 5] benzodiazepines (7, 8), have been synthesized by 1, 3‐dipolar cycloaddition reactions of 2, 3‐dihydro‐1, 5‐benzothiazepines and 2, 3‐dihydro‐1H‐1, 5‐benzodiazepine with benzonitrile N‐phenylimine and benzonitrile oxides, receptively. The conformations of some cycloadducts and cycloaddition mechanism are described.
Theoretical study on tetrazole and its derivatives (3) MP2 and thermodynamic calculations of amino derivatives of tetrazole
Authors: Chen Zhao‐Xu , Xiao He‐Ming , Gao Bao‐Hua
Published: September 2010

Fully optimized geometries and electronic structures of amino derivatives of tetrazole are obtained at MP2/6‐31G* level. The tetrazole rings are planar and aromatic for all the amino derivatives of tetrazole. The amino group is not co‐planar with the ring and its conformation is mainly determined by the lone pair electronic repulsion between the substituents and the ring. N(4) atom is more negatively charged and is the most probable coordination site. The energy gaps between LUMOs and HOMOs of 2H‐aminotetrazoles and C‐aminotetrazole neutrals are smaller than those of the corresponding 1H‐isomers and N‐aminotetrazole neutrals respectively. The IR frequencies, thermodynamic properties and temperature‐dependent functions for heat capacities in the fom (a + bT + cT2) in the 300–1000K range are reported.
Application of charge transfer reaction in the pharmaceutical analysis—Determination of chlorhexidine acetate
Authors: Li Hua‐Kan , Zhao Feng‐Lin , Tong Shen‐Yang
Published: September 2010

A spectrophotometric method for the determination of chlorhexidine acetate is described. The reaction between chlorhexidine acetate and chloranil took place in an alcohol‐acetone solution at room temperature. The composition of the charge transfer complex is 1:2. Beer's law is obeyed in the concentration range of 15–270 μg·mL−1 with correlation coefficient 0.9995. The apparent molar absorptivity is 2.21 × 103 L·mol−1·cm−1 at 412 nm. The method is accurate (with a recovery af 100 ± 1.6% ) and precise (RSD =1.0%). It was successfully applied to determine chlorhexidine acetate in suppository or disinfectant solution.
Study of enzyme models and imitation of enzyme action
Authors: Chen Shu‐Hua
Published: September 2010

This paper deals With some of the mh activities in our group in recent years in the areas of artificial enzyme models with porphyrin, steroids and calixarenes as building units. Wherein two kinds of novel enzym models of steroids‐metalloporphyrin and calixarene‐metalloporphyrin have been synthesized and employed as cytochrome P450 modeling. These biomimetic systems exhibited high catalytic selectivity and efficiency in oxidation of olefins (styrene, cyclohexene) and hydrocarbonds (isopropylbenzene) as well as phenol (p‐benzenediol). The excellent catalytic property stems mainly from hydrophobic effect and multiple recognition sites that lead to cooperative catalysis.
Horseradish peroxidase‐mediated oxidation of carcinogenic non‐aminoazo dyes
Authors: Zhu Min , Huang Xue‐Mei , Shen Han‐Xi
Published: September 2010

Fifteen non‐aminoazo, dyes were oxidized when catalyzed by horseradish peroxidase (HRP) in the presence of H2O2. Aromaticdiazonium ions, the ultimate carcinogen, were detected in the reaction with all of azo compounds as the substrates for HRP. The rates of oxidative cleavage fairly depended on pH. Relative enzymatic activities were compared among 15 non‐aminoazo, dyes, and the structural requirements of the substrates for HRP were discussed in detail.
Synthesis crystal structure and luminescence properties of europium complexes with a new terpyridine‐like ligand
Authors: Yang Chi , Chen Xiao‐Ming , Cui Ying‐De , Yang Yan‐Sheng
Published: September 2010

New 1:1, 1:2 and 1:3 europium(III) complexes with 2, 4, 6‐tris(3,5‐dimethylpyrazol‐1‐yl)‐1, 3, 5‐triazine have been prepared, and their luminescence has been demonstrated to be sensitive to the π‐π stacking and H‐bonding interactions.
Luminescence and energy transfer between Ce3+ and Mn2+ in alkaline earth borates
Authors: Zeng Qing‐Hua , Pei Zhi‐Wu , Wang Shu‐Bing , Su Qiang
Published: September 2010

The luminescence of Ce3+ and Ce3+, Mn2+ co‐doped BaB8O13 and SrB4O7 prepared in air is studied. The results show that tetravalent cerium ion can be reduced to trivalent state in the hosts and gives rise to efficient luminescence. Energy transfer between Ce3+ and Mn2+ is possible. Mn2+ ions can be efficiently sensitized by Ge3+ and exhibit green and red emissions which implied that Mn2+ occupied the crystallographic sites of cations and boron sites of the anions, respectively. The intensity ratio of red to green emission in matrix increases with the increasing of manganese concentration.
Investigations by electrochemical quartz crystal impedance system—electrodeposition of silver and polyaniline
Authors: Xie Qing‐Ji , Liu Hong‐Wei , Zhang You‐Yu , Shou‐Zhuo Yao
Published: September 2010

An electrochemical quartz crystal impedance system (EQCIS) which allows rapid and simultaneous measurements of admittance spectra of piezoelectric quartz crystal resonance during electrochemical processes was developed by combining an HP 4395A Network/Spectrum/Impedance analyzer with an EG & G M283 potentiostat. Non‐linear least square regression analyses of simultaneously acquired conductance and susceptance data were discussed in detail, giving that Rm, Cs, 1/Cm (or Lm) and of as estimation parameters is the best choice among various fitting routines. Equivalent electrical circuit parameters of quartz crystal resonance during electrodeposition of silver and polyaniline and electrochemical processes of the deposits were obtained and discussed according to changes in electrode mass, electrode surface roughness and film conductivity etc. The significant changes of motional resistance Rm and static capacitance C, observed in the silver case was believed to result mainly from changes in electrode surface roughness and the linear relationship between them was well explained by the following equation, Cs = Cq+ Ce = εqAq/ hq + εek2Rm/[he(ωρLηL]1/2.
Oxidation of hexabenzylhexaazaisowurtzitane
Authors: Qiu Wen‐Ge , Chen Shu‐Sen , Yu Yong‐Zhong
Published: September 2010

Oxidation of hexabenzylhexaazaisowurtzitane by different Cr(VI) reagents has been studied, and a very stable amide product, hexabenzoylhexaazaisowurtzitane, has been obtained.
Laser‐induced NMR shift of a paramagnetic system
Authors: Li Li, , Dong‐Ming Chen, , Tian‐Jing He, , Xiu‐Yan Wang, , Fan‐Chen Liu,
Published: September 2010

Perturbation theory on optical ac stark effect is applied to study the NMR spectroscopy in paramagnetic systems. Application of the circularly or linearly polarized optical field would lead to shifts in the NMR line, which is proportional to the laser intensity and the induced polarizability tensors by hyperfine interaction.

The induced shift for 193Ir NMR spectrum of [ IrBr6 ]2– is expected to be of the order of 1–10 Hz as resonance is approached with light intensity 10 W*emn‐1. For the supersonic molecular beam samples 193IrC, the laser‐induced NMR shift is estimated to be as large as 1–10 MHz near resonance.
An MP2 study on pre‐reactive complexes (CH2)2O…XY (X,Y = H,F,Cl,Br,I)
Authors: Chen‐Sheng Lin, , Chm‐Wan Liu,
Published: September 2010

The structures, energies, atomic charges and IR spectra of complexes (CH2)2O…XY (X, Y = H, F, Cl, Br, and I) have been examined by means of ab initio molecular orbital theory at the second‐order level of Møller‐Plesset perturbation correction. It is found that the hydrogen bond O…H‐X is non‐linear. The attraction between X and the H atoms in oxirane ring causes O…H‐X bond bending. The hydrogen bond slightly weakens the bond strength of C‐O, and leads the bending and stretching mode of IR to shift to the red. The calculation results show that there is no evidence of a significant extent of proton transfer to give (CH2)2OH+ … X− in the isolated complexes.
Studies on the syntheses and properties of boronoalkoxycalix [4] arenes
Authors: Kui Lu, , Yang‐Jie Wu, , Yan‐Jun Xing, , Da‐Peng Zou, , Zhi‐Xian Zhou,
Published: September 2010

New boronoalkoxycalix[4] arenes were synthesized by allylation, alkylation, hydroboration and hydrolysis of 25,26,27,28‐tetraydroxycalix[4] arene, and identified by elemental analysis, IR, 1H NMR, 13C NMR, 11B NMR, Ms and UV spectra. The data of UV and fluorescence spectra showed that tetrapropoxycalix‐[4]arene triboronic acid could coordinate significantly with monosaccharides.
Studies on organophosphorus compounds 104 Reaction of carbanions derived from alkylphosphonates
Authors: Chao‐Zhong Li, , Cheng‐Ye Yuan,
Published: September 2010

Structural effect of substituents directly bonded to carbanions bearing a phosphonate moiety is examined. Nucleophilic addition of phosphonate carbanion to 1‐nitroalkene followed by subsequent reaction with chlorotrimethylsilane leads to a series of 2‐isoxazoline based on the formation of an alkene and silyl nitronate as a 1,3‐dipole. On the other hand, addition of carbanion derived from isocyanomethylphosphonate to nitroalkene with he formation of nitronate followed by intromolecular cyclization provides substituted phosphoryl pyrroles.
Interaction between nitric oxide and lipid‐like DDPA LB film investigated with SHG and AFM
Authors: An‐Chi Yu , Tlng‐Ting Liu , Guo‐Bin Luo , Li‐Ming Ying , Xin‐Sheng Zhao , Yan‐Yi Huang , Chun‐Hui Huang
Published: September 2010

Interactions between Nitric oxide (NO) and DDPA Langmuir‐Blodgett (LB) film are investigated with second harmonic generation (SHG) and atomic force microscopy (AIM). It has been found mat the adsorption of NO molecules on DDPA LB film only changes the value of the second‐order susceptibility of the DDPA molecule on film but not its orientation.
An improved ELISA for the determination of southern bean mosaic virus with linear sweep voltammetry detection based on new system of PAP‐H2O2‐HRP
Authors: Shu‐Sheng Zhang , Kui Jiao , Hong‐Yuan Chen , Cheng‐Liang Zhang , Zuo‐Fang Zhang
Published: September 2010

An improved enzyme‐linked immunosorbent assay (ELISA) for the determination of southern bean mosaic virus (SBMV) with linear sweep voltammetry based on a new system of p‐aminophenol (PAP)‐H2Q2‐horseradish peroxidase (HRP) has firstly been developed. The enzymatic product 3‐[(4‐hydroxyphenyl)amino]‐4‐(2‐amino‐5‐hydroxvphenyl)‐6‐[(4‐hydroxyphenyl)imino]‐2,4‐cyclohexadiene‐1‐one, produced from the oxidation of PAP with H2O2 catalyzed by HRP, yielded a sensitive linear sweep voltammetric response at −0.45 V (vs. SCE) in Britton‐Robinson (BR) buffer solution. Based on the voltammetric peak, HRP can be measured with a detection limit of 0.4 mU/L and a linear range of 1.0–1.0×102 mU/ L. The detection limit for the SBMV is 8.0 ng/mL and the highest dilution ratio for the detection of infected leaf sap is 1: 1.5×105.
A novel synthesis of allyl and benzyl selenides via Sm/SbCl3 system in aqueous media
Authors: Gen‐Liang Lu , Yong‐Min Zhang
Published: September 2010

Allyl and benzyl selenides were synthesized via reactions of allyl and benzyl bromides and diselenides promoted by Sm/Sb‐Cl3 system in aqueous media in moderate to good yields.
Synthesis of benzyl O‐(2,3,3′‐tri‐O‐acetyl‐β‐D‐apiofuranosyl)‐(1→3)‐2,4‐di‐O‐benzoyl‐α‐D‐xylopyranoside and its X‐ray structure
Authors: Xkng‐Ming Zhu , Biao Yu , Yong‐Zhaig Hui
Published: September 2010

The protected apiose‐containing disaccharide, benzyl O‐(2,3, 3′‐tri‐O‐acetyl‐β‐D‐apiofuranosyl)‐(1→3)‐2, 4‐di‐O‐benzoyl‐α‐D‐xylopyranoside, was synthesized and its X‐ray structure provided.
Preparation of 9,13‐dicisdouble bonds locked retinoids
Authors: Feng‐Ling Qing , Xiang‐Jun Yue
Published: September 2010

Synthesis of two retinoids in which the 9, 13‐dicisdouble bonds were locked in cycloalkene or thiophene was described. The key steps were the Wittig olefination of phosphonium salt 3 and 23 with aldehyde 14, followed by carbonylation of vinyl bromide 17 and 24 with carbon monoxide in the presence of Pd(PPh3)4.
Novel immonium type peptide coupling reagent: 5‐(1H‐benzotriazol‐1‐yloxy)‐3,4‐dihydro‐1‐methyl 2H‐pyrrolium hexachloroantimonate (BDMP® )
Authors: Peng Li , Jiccheng Xu
Published: September 2010

A novel immonium type coupling reagent, 5‐(1H‐benzotriazol‐1‐yloxy)‐3,4‐dihydro‐1‐methyl 2H‐pyrrolium hexachloroantimonate (BDMP) has been designed, synthesized and utilized to synthesize oligopeptides and biologically active peptide both in solution and solid phase with satisfactory yield, low racemization and fast reaction rate. The estimation of racemization and the influence of several reaction parameters were studied by HPLC method using the model reaction: Z‐Gly‐Phe‐OH + Val‐OMe·HCl·Z‐Gly‐D/L‐Phe‐Val‐OMe. It was shown that the reactivity of BDMP was much higher and the racemization was much lower than those of HOBt‐based ‘onium’ reagents, even though its analogues BOMI. To further verified me effectiveness of BDMP, Leu‐enkephalin was synthesized both in solution and solid phase using BDMP as coupling reagent. The proposed mechanism was also speculated.
A new pentacyclic triterpene, gmeliniin A, from Echinops gmelinii Turcz
Authors: Lan He , Qi‐Rong Chao , Rong Li , Guo‐Qiang Lin , Hao Huang
Published: September 2010

Melanin A, a new pentacyclic triterpene of ursane series isolated from the aerial parts of Echinops Gemini, is elucidated structurally as 1 on the basis of 1D and 2D NMR spectroscopic studies.
Fructose derived pyridyl alcohol ligands: Synthesis and application in the asymmetric diethylzinc addition to aldehydes
Authors: Yong‐Gui Zhou , Li‐Xin Dai , Xue‐Long Hou
Published: September 2010

Easily available chiral ketones were employed for the synthesis of optically active pyridyl alcohols, which were applied in the asymmetric diethylzinc addition to aldehydes, up to 89.4% e.e. was obtained using D‐fructose‐derived pyridyl alcohol.
An atomic electronegative distance vector and carbon‐13 nuclear magnetic resonance chemical shifts of alcohols and alkanes
Authors: Shu‐She Liu , Zhi‐Ning Xia , Shao‐Xi Cai , Yan Liu , Zhi‐Liang Li
Published: September 2010

A novel atomic electronegative distance vector (AEDV) has been developed to express the chemical environment of various chemically equivalent carbon atoms in alcohols and alkanes. Combining AEDV and γ parameter, four five‐parameter linear relationship equations of chemical shift for four types of carbon atom are created by using multiple linear regression. Correlation coefficients are R = 0.9887, 0.9972, 0.9918 and 0.9968 end roots of mean square error are RMS = 0.906, 0. 821, 1.091 and 1.091 of four types of carbons, i.e., type 1, 2, 3, and 4 for primary, secondary, tertiary, and quaternary carbons, respectively. The stability and prediction capacity for external samples of four models have been tested by cross‐validation.
Electrocatalytic oxidation of NADH at glassy carbon electrodes modified with an electropolymerized film of nile blue A
Authors: Chen‐Xin Cai , Knan‐Hong Xue
Published: September 2010

The kinetic parameters for the etectrocatalytic oxidation of dihydronicotiamide adenine dinucleotide (NADH) at glassy carbon electrodes modified with an electropolymerized film of nile blue A (PNB) have been determined based on rotating disk electrode measurements. The rate constant for the chemical reaction between NADH and PNB is strongly influenced by NADH concentration and the pH value of solution, and it decreases with increasing NADH concentration, indicating that the electrocatalytic process proceeds via the formation of an intermediate of charge‐transfer complex between NADH and PNB.
Protection‐deprotection method in synthesis of calixarene derivatives
Authors: Guo‐Yuan Lu , Qian Li , Fang Liu , Xiao‐Bin Wan
Published: September 2010

The debenzylation and selective de‐tert‐butylation of p‐tert‐calix[4]arene derivatives were studied and 11, 17, 23‐tri‐tert‐butyl‐25, 26, 27‐tri‐O‐etherated calix[4] arenes were synthesized by a simultaneous debenzylation and selective de‐tert‐butylation process.
A new process for preparing dialdehyde by catalytic oxidation of cyclic olefins with aqueous hydrogen peroxide
Authors: Hong‐Kun Yu , Zhen Pang , Zu‐En Huang , Rui‐Fang Cai
Published: September 2010

A novel peroxo‐niobophosphate was synthesized for the first time and used as a catalyst in the oxidation reaction of cyclic olefins with aqueous hydrogen peroxide to prepare dialdehydes. The catalyst was characterized by elemental analysis, thermographic analyses, IR, UV/vis, 31P NMR and XPS spectra as [πC5H5N(CH2)13CH3]2[Nb4O6(O2)2(PO4)2]·6H2O (PTNP). It showed high selectivity to glutaraldehyde in the catalytic oxidation of cyclopentene with aqueous hydrogen peroxide in ethanol.
Vibrational frequencies of hydrazoic acid and methyl azide: density functional theory study
Authors: Zheng‐Yu Zhou , Dong‐Mei Du , Ai‐Ping Fu , Qing‐Sen Yu
Published: September 2010

Harmonic vibrational frequencies of HN3 and CH3N3 molecules and their several isotopomers are calculated using HF, MP2 and five popular density functional theory (DFT) methods. On the basis of the comparison between calculated and experimental results, assignments of fundamental vibrational modes are examined. HF and MP2 results are in bad agreement with experimental values. Of the five DFT methods, BLYP reproduces the observed fundamental frequencies the most satisfactorily. Two hybrid DFT methods are found to yield frequencies generally higher than the observed fundamental frequencies. The results indicate that BLYP calculation is a very promising approach for understanding the observed spectral features.
Hydrophobically modified polyelectrolytes: I. Dilute solution properties of fluorocarbon‐containing poly (acrylic acid)
Authors: Hui Zhou , Guo‐Qiang Song , Yun‐Xiang Zhang , Ma Deeing, Reinhold , Lukas Lian Haeussling
Published: September 2010

Dilute solution viscosity of fluorocarbon‐containing hydrophobically modified poly (acrylic add) was measured in aqueous solutions of various NaCl concentrations. The intrinsic viscosity ([η]) and Huggins coefficient (kH) were evaluated using Huggins equations. It is found that, at low Nacl concentration, the modified polymers exhibit values of intrinsic viscosity ([η]) and Huggins coefficient (kH) similar to those of unmodified polymers. For both of the modified and unmodified polymers, the intrinsic viscosity decreases with increase of NaCl concentration, while the Huggins coefficient increases upon addition of NaCl. But the variation of [η] and kH is more significant for the modified polymers, which reflects the enhanced intra‐ and intermolecular hydrophobic association at higher Nacl concentration.
Effects of Pt diffusion barrier layer on the interface reaction and electric properties of PZT film/Si(111) sample
Authors: Yong‐Fa Zhu , Pei‐Yu Yan , Tao Yi , Li‐Li Cao , Long‐Tu Li
Published: September 2010

The effects of the Pt diffusion barrier layer on the interface diffusion and reaction, crystallization, dielectric and ferroelectric properties of the PZT/Si(111) sample have been studied using XPS, AES and XRD techniques. The results indicate that the Pt diffusion barrier layer between the PZT layer and the Si substrate prohibits the formation of TiCx, TiSix and SiO2 species in the PZT layer. The Pt barrier layer also completly interrupts the diffusion of Si from the Si substrate into the PZT layer and impedes the diffusion of oxygen from air to the Si substrate greatly. Although the Pt layer can not prevent completely the diffusion and reaction between oxygen and silicon, it can prevent the formation of a stable SiO2 interface layer on the interface of PZT/Si. The Pt layer reacts with silicon to form PtSix species on the interface of Pt/Si, which can intensify the chemical binding strength between the Pt layer and the Si substrate. To play a good role as a diffusion barrier layer, the Pt barrier layer must be not thinner than 140 nm. The existence of the Pt layer not only promotes the crystallization of PZT layer to form a perovskite phase but also improves dielectric and ferroelectric performances of the PZT layer.
Catalytic decomposition of CFC‐12 on solid acids SO42‐/MxOy (MZr, Ti, Sn, Fe, Al)
Authors: Zhen Ma , Wei‐Ming Hua , Yi Tang , Zi Gao
Published: September 2010

The catalytic decomposition of dichlorodifluoromethane (CFC‐12) in the presence of water vapor on a series of SO42−‐promoted solid adds was investigated. CFC‐12 was decomposed completely on SO42−/ZrO2, SO42−/TiO2, SO42−/SnO2, SO42−/ Fe2O3 and SO42–/Al2O3 at 265°C, 270°C, 325°C, 350°C and 325°C, respectively, and the selectivity to by‐products was neglectable. Obvious deactivation was found on SO42−/ZrO2 and SO42−/Al2O3, during several hours on stream, while the catalytic activity was maintained on SO42−/TiO2, SO42−/SnO2 and SO42−/Fe2O3 for 240 h on stream.
Synthesis and characterization of semicarbazone metal complexes of Sn(IV) and Zr(IV)
Authors: Dong‐Dong Yin , Zhi‐Wen Wang , Lu Shan
Published: September 2010

Three semicarbazonyl ligands were synthesized and used to form six novel organometallic complexes with Ph2SnCl2 and Cp2ZrCl2. All these complexes were characterized by IR 1H NMR MS and elemental analysis.
Synthesis of furo[3,2‐c]‐ and pyrano[3,2‐c ]quinolines by lanthanide triflate catalyzed imino‐Diels‐Alder reaction
Authors: Yun Ma , Chemg‐Tao Qian , Mei‐Hua Xie , Jie Sun
Published: September 2010

Imino Diels‐Alder reaction of imines with 2,3‐dihydrofuran or 3,4‐dihydro‐2H‐pyran proceeded smoothly in the presence of a catalytic amount (0.5 mol %) of ytterbium triflate to afford furo[3,2‐c]‐ and pyrano[3,2‐c] quinolines conveniently in high yield.