bluuebunny/crossref_metadata_2025 huggingface dataset:
Structure and electrospray mass spectrometry studies on dithiacyclooctan‐3‐ol‐containing palladium (II) complex of trans ‐[Pd‐(dtco‐3‐OH)2] (ClO4)2·2DMSO
Authors: Xue‐Mei Luo , Yong‐Jiang Liu , Yu‐Hua Mei , Long‐Gen Zhu
Published: September 2010

The structure of trans‐[Pd‐(dtco‐3‐OH)2] (ClO4)2·2DMSO, in which dtco‐3‐OH is dithiacyclooctan‐3‐ol and DMSO is dimethyl sulfoxide, was determined by X‐ray crystallographic analysis. The crystal data: space group p1, a = 0.7077(2) nm, b = 1.0788(1) nm, c = 1.1111(1) nm, α = 67.710(8)°, β = 73.59(2)°,γ = 85.39(2)°, R1 = 0.0368 and Rw = 0.0998. The palladium (II) is coordinated by four sulfur atoms with a regular square planar configuration. The Pd—S distances are 0.2314(1) and 0.2317(1) nm, respectively. Both dtco‐3‐OH ligands are in the boat‐chair configuration and two hydroxyl groups are on the opposite sites of the PdS4 coordination plane and are towards Pd(II). The Pd—O distance is 0. 285 nm, indicating a weak interaction between them. A typical hydrogen bond between the hydroxyl group of dtco‐3‐OH ligand and DMSO was observed in the crystal structure. An aqueous solution prepared with the crystals of the complex was used for the investigation of electrospray mass spectrometry (ESMS). Besides trans‐[ Pd (dtco‐3‐OH)2]2+ . 2DMSO observed, in the full scan spectrum of ESMS, all relative species of it, which were probably produced during electrospray ionization process, were also detected. From these experiments, it reveals that ESMS is a powerful tool for studying noncovalent interaction present in solution between inorganic complexes and solvents.
Molecular design of crown ethers. 18.1 Cation extractability and selectivities of selena‐13‐to 14‐crown‐4
Authors: Yu Liu , Heng‐Yi Zhang
Published: September 2010

Three selena‐crown‐4 derivatives have been prepared and their cation hinting 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 novel benzo‐selena‐14‐crown‐4 (2,3‐benzo‐7, 12‐diselena‐1, 4‐dioxacyclotetradecane‐2‐ene) over any other crown ethers.
Synthesis and nitration of calix[4] (aza) crowns
Authors: Qi‐Yu Zheng , Chuan‐Feng Chen , Zhi‐Tang Huang
Published: September 2010

Calix[4] (aza) crowns containing amide groups 3a—d were synthesized by the reactions of calix[4]arene (la) or p‐tert‐butylcalix[4]arene (1b) with N, N′‐ethylenebis(2‐chloroacetamide) (2a) or N, N′‐ 1,2‐ethylenebis (2‐chloroacetamide) (2b) by one step procedure in yields of 85—‐90%. Calix[4]‐(aza) crowns 4a—b could be obtained by the reduction of 3a—b with LiAlH4 in yields of 51 and 67%, respectively. The nitration of 3a or 3c afforded new chromogenic calix[4]arenes 5a bearing two nitrophenol moieties and 5c bearing one nitro‐phenol and one quinone moiety, respectively. The ipso‐nitration's of 3b and 3d were also studied. Both gave the products containing one nitro phenol and one quinine moiety. Moreover, a very interesting calix[4]arene derivative 5d containing one cyclohexadienone moiety was also separated as the main product when 3d was ipso‐nitrated.
Molecular‐level investigation on electrochemical interfaces by Raman spectroscopy
Authors: Zhong‐Qun Tian , Bin Ren
Published: September 2010

The structure and dynamics of electrode/liquid interfaces play an increasingly important role in electrochemistry. Raman spectroscopy is capable of providing detailed structural information at molecular level and new insight into the interfacial structure, adsorption, reaction, electrocatalysis and corrosion. In this account we will summarize some progresses of surface Raman spectroscopy in the study of electrochemical interfaces, mainly based on our group's work, laying emphasis on the detection sensitivity, spectral resolution, time resolution and spatial resolution as well as the hyphenated technique.
Photoinduced electron transfer of [ Ru (bpy)2 (4,4′‐dcbpy) ]2+ with electron donors
Authors: Pu‐Hui Xie , Lian‐Qi Zhang , Yuan‐Jun Hou , Bao‐Wen Zhang , Yi Cao , Fang Wu , Wen‐Jing Tian , Jia‐Cong Shen
Published: September 2010

Emission quenching of [Ru(bpy)2(4,4′‐dcbpy) ] (PF6)2 (1) by benzenamine,4‐[2‐[5‐[4‐[4‐dimethylamino]phenyl]‐4,5‐dihydro‐l‐phenyl‐1H‐pyrazol‐3‐yl]‐ethenyl]‐N, N‐dimethyl (2) or 1,5‐diphenyl‐3–(2‐phenothiazine)‐2‐pyrazoline (3) was observed. Measurements of the emission decay of 1 before and after addition of 2 or 3 by single photon counting technique confirmed the observations. The emission quenching of 1 by 2 or 3 was submitted to Stern‐Volmer equation. It was calculated that the quenching rate constants (Kq) are 5.5×109 (mol/L)−1s−1 for 2 and 4.0×109 (mol/L)−1 for 3, respectively. These results indicated a character of dynamic quenching process. The singlet‐state of 2 or 3 was also quenched by 1. The quenching behaviors did not conform to the Stern‐Volmer equation and involved both static and dynamic quenching processes. The apparent quenching rate constant (kapp) was calculated to be 3×109 (mol/L)−1 for the interaction of excited 2 with 1, and 1.2×109 (mol/L)−1 for that of excited 3 with 1.
Adsorption isotherms for benzene on diatomites from China
Authors: Yu‐Xiang Yang , Jie‐Da Wu , Zhong‐Liang Jiang , Meng‐Jian Huang , Rong‐San Chen , An‐Bang Dai
Published: September 2010

In this paper, benzene adsorption isotherm and their hysteresis on two important local diatomites were determined at 25°C, and their silicon hydroxyl group (SiOH) number was determined, their properties were reported, and the relationship between surface structure, surface SiOH number per nm2 and adsorption isotherm with hysteresis was discussed. The specific surface was also calculated from the isotherms, and pore‐size distribution was determined.
Theoretical study on second‐order nonlinear optical properties of unsymmetric bis (phenylethynyl) benzene series derivatives
Authors: Wei Fu , Ji‐Kang Feng , Kun‐Qian Yu , Ai‐Min Ren , Meng Cui , Yao‐Xian Li , Chia‐Chung Sun
Published: September 2010

On the basis of ZINDO methods, according to the sum‐overstates (SOS) expression, the program for the calculation of the second‐order nonlinear optical susceptibilities βijk and βμ of molecules was devised, and the structures and nonlinear optical properties of unsymmetric bis(phenylethynyl) benzene series derivatives were studied. The influence of the molecular conjugated chain lengths, the donor and the acceptor on βμ was examined.
Investigation of retention and chiral recognition mechanism using quantitative structure‐enantioselectivity retention relationship in high performance liquid chromatography
Authors: Hui Chen , Xian‐Yu Lu , Ru‐Yu Gao , Jun‐Min Huang , Hua‐Zheng Yang , Qun‐Sun Wang
Published: September 2010

The enantiomers of a series of fourteen O‐ethyl O‐(substituted) phenyl N‐isopropyl‐phosphoroamidothioates have been separated by high performance liquid chromatography (HPLC) on the Pirkle‐type chiral stationary phase. Seven molecular descriptors were calculated and four significant descriptors were chosen to correlate against the experimental lnk' values in order to form the quantitative structure‐enantioselectivity retention relationships (QSERRs). Through the QSERRs, the retention and enantioselectivity mechanism were examined.
Steroid‐bismetalloporphyrin as enzyme model of cytochrome P‐450 monooxygenase
Authors: Shu‐Hua Chen , Shang‐Jun Li , Yu‐Liang Wang
Published: September 2010

The model compounds of androgenic steroid‐bismetalloporphyrins 3a—3d and androgenic monometalloporphyrins 2a—2d have been synthesized. Catalytic study in two‐phase condition on epoxidation of styrene under the catalysis of model catalysts shows that the catalytic performances of steroid‐bismetalloporphyrin is superior to steroid‐metalloporphyrin and the corresponding simple metalloporphyrin. The excellent catalytic property of steriod‐bismetalloporphyrin can be rationalized as the hydrophobic action of steroid framework and the cooperative action of two metalloporphyrins in catalysis.
A new strategy for the synthesis of unsymmetrical phosphotriesters
Authors: Jun Hu , Yi‐Xiang Ding
Published: September 2010

A new strategy for the synthesis of unsymmetrical phosphotriesters was reported: an alcohol was converted to unsymmetrical dialkyl phosphites firstly, which then reacted with the second alcohol or phenol to afford required unsymmetrical triesters in the presence of iodine in high yields under exceptionally mild conditions.
A facile approach for the construction of the oxetane ring from 5α‐acyloxy‐△4(20)‐taxoids
Authors: Rui‐Wu Liu , Da‐Li Yin , Ji‐Yu Guo , Xiao‐Tian Liang
Published: September 2010

An oxetane ring can be constructed from 5 α‐acyloxy‐Δ4(20)‐taxoids. The facile intramolecular acyl migration from 5‐ to 20‐position under slightly basic conditions enabled the construction of the oxetane ring in a convenient short cut, whereas the acyl migration from 2‐ to 20‐position left the 2‐hydroxyl accessible to a later benzoylation. An unexpected five‐membered 4‐0, 20‐0 sulfite ring was formed in the attempted construction of the oxetane ring with 5α‐triflate as a leaving group. After the construction of the oxetane ring, treatment with strong base LiHMDS and acetyl chloride gave the expected 4‐0‐acetate while treatment with acetic anhydride and DMAP gave a 4‐0‐acetoacetate.
Density Functional Theory (DFT) studies on the ground state of NO3(2A′2) radical and the first triplet state of NO3+cation
Authors: Xiao‐Yan Cao , Gong‐Yi Hong , Dian‐Xun Wang , Le‐Min Li , Guang‐Xian Xu
Published: September 2010

Density Functional Theory (DFT) studies on the ground states (2A′2) of NO3 radical and on die ground state (1A′;1) and the first triplet state (3E″) of NO3+ cation provide an unambiguous prediction about their geometrical structure: the ground states of both NO3 radical and NO3+ cation have D3h symmetry and the geometrical configuration of me first triplet state 3E″ of NO3+ cation has C2v symmetry. It is shown that as for as the ionization energy calculations on NO3 radical are concerned, the results are only slightly different, no mater that gradient corrections of the exchange‐correlation energy are included during self‐consistent iterations or they are included as perturbations after the self‐consistent iterations.
Expansion of potential 1/r12 of c‐spherical harmonics
Authors: Ai‐Ling Wu , Cong‐Hao Deng , Lu Deng
Published: September 2010

The expansion coefficient CD|L| of Coulomb potential 1/r12 of atomic system in hyper‐spherical harmonics is derived and the explicit expression is given.
Kinetic and thermodynamic properties of the aerial oxidation of hydroquinone in developer solutions
Authors: Asadollah Nasehzadeh , Hossain Resa, Sayyed , Azita Khosravan
Published: September 2010

The aerial oxidation kinetics of hydroquinone in a freshly prepared developer solution at different temperatures and pHs has been studied. The activation parameters, Ea, ΔG#, ΔS#, ΔH# and enthalpy of formation of activated complex, ΔH0f(X# ), are determined. The large negative value of free energy of activation ΔG# proves that hydroquinone extremely tends to be oxidized by air at optimum temperature (20°C and optimum pH (10.5) and converts to the activated complex semiquinone. It was also found that if the pH of the developer solution is increased from 9.3 to 10.5 the reaction rate will increase by a factor of 2.
Photolysis of hexaarylbiimidazole sensitized by dyes and application in photopolymerization
Authors: Fang Gao , Jin‐Qi Xu , Xiao‐You Song , Li‐Dong Li , Yong‐Yuan Yang , Shu‐Jing Feng
Published: September 2010

Kinetic studies on the near‐UV photo‐initiating polymerization of methylmethacrylate (MMA) sensitized by dye/hexaarylbiimidazole systems were carried out. When exposed to high‐pressure mercury lamp (filtered by Pyrex glass), dye/hexaarylbiimidazole system undergoes quick electron transfer and free radicals are produced. RSH, as hydrogen donor, can improve the polymerization efficiency of MMA. Comparisons of influence of different dyes and different RSH on the conversion of MMA photopolymerization were carried out. Excellent results have been obtained in photoimaging studies, e.g. a minimum exposure energy of the photosensitive systems of 8 mJ/cm2 can be reached and the resolution of presensitized printing plate was ca. 10 μm.
A density functional study on the electronic structures of TiN solid
Authors: Jun‐Qian Li , Yong‐Fan Zhang
Published: September 2010

The electronic structures of TIN bulk have been studied by using different theoretical formalisms, and the DFT method, especially the BLYP method can produce reasonable results. The band structure of TIN(00l) surface is also investigated and two σ type surface states are presented in our results. The state located at 2.9 eV below EF in angle resolved photoemission in (ARPES) is well reproduced in this work, which consists essentially of 2pz orbital of surface N atom. Another surface state is associated with the bands originated from 3d orbital of surface Ti atom. Furthermore, the elastic constants of TiN are also calculated by using BLYP method.
Electrical characteristics of chlorophyll‐a polyvinyl alcohol photovoltaic cells
Authors: Yun‐Yu Han , Zhao‐Yu Diao , Huai‐Xiang Li , Yan‐Hui Chi
Published: September 2010

A type of photovoltaic cell was made by sandwiching micro‐crystalline chlorophyll‐a (chla) layer and polyvinyl alcohol (PVA) film between two semiconductive optical transparent SnO2 electrodes, such as SnO2/chla/PVA/SnO2. The cell showed a dark rectifying effect and presented photovoltaic properties on illumination, which was illustrated by the charge distribution in the cell. It was suggested mat the SnO2/chla junction might be responsible for photovoltage and the chla/ PVA for the charge separation upon irradiation of visible light. The equivalent electric circuit was discussed and its equivalent component values were calculated.
Synthesis, characterization and magnetism of binuclear cobalt (II) complexes bridged by tetracarboxylato groups
Authors: Cui‐Wei Yan , Yan‐Tuan Li , Dai‐Zheng Liao
Published: September 2010

Three new binuclear cobalt (II) complexes with extended tetracarboxylato‐bridge have been synthesized and characterized, namely [Co2 (PMTA) (bpy)4] (1), [Co2(PMTA)‐(phen)4] (2) and [Co2(PMTA)(NO2phen)4 (3), where PMTA represents the tetraanion of pyromellitic acid, and bpy, phen, NO2‐phen denote 2,2‐bipyridine, 1,10‐phenanthroline; 5‐nitro‐1, 10‐phenanthroline, respectively. Based on elemental analyses, molar conductivity measurements, IR and electronic spectra studies, it is proposed that these complexes have PMTA‐bridged structures and consist of two cobalt(II) ions, each in a distorted octahedral environment. These complexes were further characterized by variable temperature magnetic susceptibility measurements (4–300 K) and the observed data were successfully simulated by th e equation based on the spin Hamiltonian operator, Ĥ=−2J Ŝ1·Ŝ2, giving the exchange integral J= −1.02 cm−1 for 1, J= −1.21 cm−1 for 2 and J = −1.18 cm−1 for 3, respectively. These results revealed the operation of antiferromagnetic spin‐exchange interaction between the two Co(II) ions within each molecule.
Synthesis of novel modified p‐cyclodextrins and their fluorescence studies of inclusion complexation with Rhodamine B
Authors: Lan Jin , Yu Liu
Published: September 2010

Three novel β‐cyclodextrin derivatives have been synthesized and their inclusion complexation behavior with Rhodamine B (RhB) was investigated by the fluorescence spectroscopy.
Practical synthesis of new functionalized tetraphenylenes
Authors: Da‐Ming Du , Ling‐Ping Zhou , Jian‐Wu Wang , Shao‐Kun Wang
Published: September 2010

The practical synthesis procedure of substituted tetraphenylene derivatives involving the synthesis of a precursor for 4,7‐dimethoxyisobenzofuran and Diels‐Alder addition of 4,7‐dimethoxyisobenzofuran generated in situ to 5,6,11,12‐tetradehydrodibenzo[a,e]cyclooctene, followed by a low valent titanium mediated deoxygenation to give 1,4,11,14‐tetra‐methoxy‐dibenzo[b, n]tetraphenylene, which can be further demethylated to the corresponding phenolic compound, which was acetylated to afford 1,4,11,14‐tetraacetoxy‐dibenzo[b,n] tetraphenylene.
Off‐diagonal long‐range order of the wave function in terms of the alternate molecular bonding geminals
Authors: Wen‐Cai LÜ , Chia‐Chung Sun
Published: September 2010

It is shown that in the quantum structural approach to high‐Tc superconductivity, the wave function in terms of the alternate molecular bonding geminals possesses off‐diagonal long‐range order (ODLRO).
Resistance of the anodic PbO film formed in sulfuric acid solution
Authors: Hou‐Tlan Liu , Hai‐He Liang , Jiong Yang , Wei‐Fang Zhou
Published: September 2010

The resistance of the anodic PbO film formed on lead at 0.9 V (vs. Hg/Hg2SO4) in 4.5 mol/dm3 H2SO4 was measured using alternating‐current impedance method. The resistance of the anodic PbO film was found to be close to that of the interstitial liquid among the PbO particles in the film, suggesting mat the interstitial liquid may serve as the major passage for ion transportation during the film growth.
Synthesis electro structure and spectral property of oligo(phenylene vinylenes) with different chain lengths
Authors: Jing‐Zhi Sun , Fang Wu , Wen‐Jing Tian , Yu‐Guang Ma , Yu Chen , Jia‐Cong Shen
Published: September 2010

The syntheses of a series of oligo (phenylene vinylenes) (OPVs) were described. The extended π‐chains were built up by sequences of Wittig reactions. Their electronic structures were systematically studied with absorption spectra, photo‐luminescent spectra. The influences of the effective conjugation length on the performance of the light emitting devices were investigated.
Separation of chiral phosphorus compounds on the substituted β‐cyclodextrin stationary phase in normal‐phase liquid chromatography
Authors: Hyi Chen , Xian‐Yu Lu , Ru‐Yu Gao , Jia Zhou , Qin‐Sun Wang
Published: September 2010

The separation of enantiomers of a series of eighteen novel nitrogen mustard linked phosphoryl diamide derivatives was investigated on the prepared phenyl carbamate derivative β‐cyclodextrin bonded phase in normal‐phase HPLC. Some of the enantiomers could be separated in baseline. The chiral recognition mechanism was also suggested for the separation of chiral phosphorus organic compounds.
Synthesis and crystal structure of polymer cobalt(II) complex, 1,2,4,5‐benzenetetracarboxylate hexaimidazole tetraaqua cobalt (II) tetrahydrate
Authors: Shun Wang , Mao‐Ling Hu , Jl‐Xin Yuan , Ya‐Qian Cheng , Juan‐Juan Lin , Zhen‐Yan Huang
Published: September 2010

The crystal structure of the title complex { [ Co (TCB)2/2‐(IMI)2(H2O)2][Co(IMI)4(H2O)2]}[(H2O)4 (where TCB = 1,2,4,5‐benzenetetracarboxylic anion; IMI= imidazole) has been determined by X‐ray diffraction method. Crystal data for {[Co(TCB)2/2(IMI)2(H2O)2][Co(IMI)4(H2O)2]}‐(H2O)4: triclinic, space group P 1, a = 1.0647(2) nm, b =1.1165(1) nm, c = 1.00361(1) nm, α = 91.56(1)°, β = 111.34(1)°, γ= 115.642(10)°, V = 0.9772(3) nm3, Z = l. The polymer cobalt(II) complex has a novel three‐dimension network structure. Co(1) atom and Co(2) atom both are coordinated in an octahedral arrangement and located in the center of the coordination anion and the center of the coordination cation, respectively. Moreover four carboxyl groups of TCB are divided into two types, two para‐carboxyl groups bridge Co (1) atom in monodentate fashion and other two para‐carboxyl groups are in free.
Synthesis, characterization and magnetism of μ‐chloranilato binuclear chromium (III) complexes
Authors: Yan‐Tuan Li , Cui‐Wei Yan , Yong Chen , Xian‐Cheng Zeng , Dai‐Zheng Liao
Published: September 2010

Five new chloranilato‐bridged binuclear chromium (III) complexes have been synthesized and Identified as [Cr2(CA)L4]‐(ClO4)4[L denotes 5‐methyl‐1,10‐phenanthroline (Me‐phen); 2,9‐dimethyl‐1,10‐phenanthroline (Me2‐phen); 5‐chloro‐1,‐10‐phenanthroline (Cl‐phen); diaminoethane (en) or 1,3‐diaminopropane (pn)], where CA represents the dianion of chloranilic acid. Based on elemental analyses, molar conductivity and magnetic moment of room‐temperature measurements, and IR and electronic spectral studies, it is proposed that these complexes have CA‐bridged structures and consist of two chromium (III) ions, each in an octahedral environment. The complexes [Cr2(CA)(Me‐phen)4](ClO4)4(1) and [Cr2(CA)(Me2‐phen)4](CIO4)4(2) were further characterized by variable temperature (4.2–300 K) magnetic susceptibility measurements and the observed data were successfully simulated by the equation based on the spin Hamiltonian operator, Ĥ= ‐2 JŠ1·Ŝ2, giving the exchange parameterJ= ‐7.8 cm−1for (1) andJ= ‐6.5 cm1for (2). This result indicates that there is weak ant ferromagnetic spin‐exchange interaction between the two chromium (III) ions within each molecule.
Enantioselective addition of EtzZn to aldehydes catalyzed by chiral aliphatic β‐amino alcohols
Authors: Zong‐Xuan Shen , Xue‐Nong Xu , Xiao‐Feng Liu , Li‐Fen Zhang , Ya‐Wen Zhang
Published: September 2010

This paper describes the preparation of two new optically active aliphatic β‐amino alcohols (R)‐5,5‐dimethyl‐2–(dimethylamino)‐1, 1‐diphenyl‐1‐bersanol (la) and (S)‐8,8‐dimethyl‐2–(dimethylamino)‐1, 1‐diphenyl‐1‐nonanol (1b). They were synthesized by methylation of the corresponding β‐amino alcohols 2a and 2b. Compounds 1a and 1b catalyze the addition of diethylzinc to various aldehydes enantioselectivity. The catalyst structure‐enantioselectivity relationships were discussed.
Synthesis of novel herbicidal sulfonylureas
Authors: Guang‐Fu Yang , Hua‐Zheng Yang
Published: September 2010

Novel sulfonylurea derivatives containing five‐membered heterocycle 3a—1 and 4a—d were synthesized in good yields by the regioselective addition of aryl sulfonylisocyanates 1 to 5‐amino‐3‐benzyl(aryl) thio‐1,2,4‐triazoles and its pyrazole analogues 2. The structures of all these compounds were evaluated by elemental analyses and 1H NMR spectroscopy. The preliminary biological tests showed that the products displayed herbicidal activity against rape to some extent.
Synthesis of some new fused coumarin derivatives
Authors: Ibrahim Mohey El‐Deen , H.K. IBRAHIM , F.F. MAHMOUD
Published: September 2010

2‐Hydrazino‐4‐hydroxy‐5H‐[1]‐benzopyrano‐[4,3‐d]‐pyrimidin‐5‐one (3) was prepared via condensation of 2 with hydrazine hydrate. Treatment of 3 with methylene chloride, ethyl chloroformate, ethyl chloroacetate and benzaldehyde yielded the corresponding 2 ‐ ( substituted ) hydrazino ‐ 4 ‐hydro‐xy‐5H‐[1]‐benzopyrano‐[4,3‐d]‐pyrimidin‐5‐one (4, 5, 6, and 10), followed by cyclization of 4, 5 and 6 with dimethyl formamide and fused sodium acetate under reflux, while compound 10 was cyclized with bromine and sodium acetate in acetic acid. Compound 3 reacted with β‐(toloyl) acrylic acid, ethyl α‐cyano‐p‐methoxycinnamate, diethyl malonate and acetyl chloride affording the corresponding 2‐(substituted) hydrazino‐4‐hydroxy‐5H‐[1]‐benzopyrano‐[4,3‐d]‐pyrimidin‐5‐one (12, 13, 14, 15 and 16).
Synthesis of polyamide containing pyrrole and imidazole amino acids
Authors: Jun‐Hua Xiao , Wei‐Qiang Huang , Fei‐Li Tang , Gu Yuan , Alberts. C. Chan , Daniel Lee, K‐L
Published: September 2010

A polyamide containing N‐methylpyrrole (Py) and N‐methylimidazole (Im) amino acids was synthesized by coupling two of the four‐ring oligopeptide chains using DCC/ HOBT as promoting additives. The structure of the polyamide was confirmed by IR, NMR and MS spectra.
Study of the aggregation of 1‐alkanoylperylenes in 1,4‐dioxane‐H2O binary solvents—Derivation of a new empirical equation relating CAgC to both chain‐length and solvent aggregating power
Authors: Ji‐Liang Shi , Jia‐Yi Xu , Hu‐Nan Yi , Xi‐Kui Jiang
Published: September 2010

Aggregation behaviors of 1‐alkanoylperylenes (Pe‐n, n = 4, 8, 12) driven by hydrophobic‐lipophilic interaction (HLI) have been investigated in dioxane (DX)‐H2O binary aquiorgano solvents by means of fluorescence spectroscopy. A novel empirical equation, which rationalizes CAgC (critical aggregate concentration) dependence of the aggregates both on the chain‐length of the substituent alkyl group and on the solvent aggregating power (SAgP) for Pe‐n, has been derived.
Synthesis, molecular structure and intramolecular aromatic‐ring stacking interaction of a novel binuclear Cu(II) complex with 1,10‐phenanthroline and phenylacetate
Authors: Xue‐Yi Le , Xiao‐Hua Zhou , Kai‐Bei Yu , Liang‐Nian Ji
Published: September 2010

The complex [Cu (phen)2(POAc)3 ]ClO4·4h2O has been synthesized and investigated by elemental analysis, IR spectroscopy and X‐ray diffraction methods, where phen = 1,10‐phenanthroline, POAc− = phenylacetate group). The complex crystallizes in the triclinic space group Pi with two molecules in a unit cell of dimensions a = 1.0579(2) nm, b = 1.2423(3) nm, c = 1.9190(4) nm, a = 71.84(1)°, β = 80.50(2)°, Y = 88.60(1)°, V = 2.3625(9) nm3, R =0.0407 and Rw = 0.0656. The complex results from bridging of two Cu (phen)2+ units by three carboxylate groups, and each Cu2+ ion is in a distorted square pyramidal geometry with two nitrogen atoms of phen and three carboxylate oxygen atoms of POAc−. It has been showed that intramolecular stacking interactions occur between the phenyl moieties of POAc− and aromatic rings of phen, leading to a novel molecule structure with two coordinating modes of carboxylate ligands, of which two phenylacetates are μ2—carboxylate—O‐bridging ligands, and the other is a μ2—carboxylate—O,O′‐bridging ligand.
Synthesis, characterization and application of soluble fullerenated polymer materials
Authors: Chen Yu , Cai Rui‐Fang , Huang Zu‐En , Wang Jing‐Xia
Published: September 2010

This article only deals with the topic of intense interest to us and to a considerable extent of our own experimental results on the synthesis, characterization and application of C60‐containing functional polymers such as poly(N‐vinylcarbazole), polystyrene and polyacrylonitrile‐based fullerene polymers. The results demonstrate that [60]fullerene and be directly incorporated into a variety of functional polymers by copolymerization or grafting, but also can be used to modify or improve the electronic, optical and physicochemical properties of polymers. Both the stereo‐electroniceffect and me steric hindrance of C60 have an important influence on the structure and physicochemical properties of the parent polymer.
Self‐assembled gold nanoparticles on functionalized gold(111) studied by scanning tunneling microscopy
Authors: Peng Zhang‐Quan , Wang Er‐Kang
Published: September 2010

Nanogold colloidal solutions are prepared by the reduction of HAuClO4 with sodium citrate and sodium borohydride. 4‐Aminothiophenol (ATP) self‐assembled monolayers (SAMs) are formed on gold(111) surface, on which gold nanoparticles are immobilized and a sub‐monolayer of the particles appears. This sub‐monolayer of gold nanoparticles is characterized with scanning tunneling microscopy (SIM), and a dual energy barrier tunneling model is proposed to explain the imageability of the gold nanoparticles by SIM. This model can also be used to construct multiple energy barrier structure on solid/ liquid interface and to evaluate the electron transport ability of some organic monolayers with the aid of electrochemical method.
Synthesis, spectra and conductivity of 1‐D polymers of nickel(I)‐and copper(II )‐porphyrazine with sulfur bridges
Authors: Peng Zheng‐He , Wang Shou‐Xing , Yang Li‐Fen , Qin Zi‐Bin
Published: September 2010

The title polymers PNIPzS4 and PCuPzS4 were synthesized by reaction of phthalonitrile and 2,3,5,6‐tetracyano‐1,4‐dithiin with corresponding metal salt. Their structures and properties were characterized by associating the experimental results with MO and Cl calculations of the dimer molecule as model polymer in the ZINDO method. It has been found that the PNiPzS4 (or PCuPzS4) shows the semiconductivity at T < 253 K (or 260 K) and T > 278 K (or 286 K) and the conductivity increase with a hoist of temperature at 253 K (or 260 K) < T < 278 K (or 286 K). The conductivity σ of the PNiPzS4 and PCuPzS4 under pressure 13.73 MPa is 1.56×10−4 and 9.33×10−5 S/cm, respectively.
A new class of rhodium complexes containing free donor atoms and their intramolecular substitution reaction
Authors: Jiang Hua , Diao Kai‐Sheng , Pan Ping‐Lai , Zhang Shu‐Feng , Yuan Guo‐Qing
Published: September 2010

A new class of rhodium complexes with high catalytic activity as well as excellent stability, which was used as catalyst for carbonylation of methanol to acetic acid, is reported. It contains free donor (namely un‐coordinated donor) atoms which enable to improve its stability by intramolecular substitution reaction. Its synthesis, characteristic and catalytic reaction were discussed here.
Photoinduced charge injection from excited triplet hypocrellin B into TiO2 colloid in ethanol
Authors: Wu Tao , Shen Jian‐Quan , Tian Chun‐Hong , Song Ai‐Min , Li Wen , Chen Shen , Zhang Man‐Hua , Shen Tao
Published: September 2010

Photosensitization of TiO2 colloid by hypocrellin B (HB), a natural photodynamic pigment with extremely high photostability, has been studied by surface enhanced Raman spectroscopy (SERS), laser flash photolysis and electron paramagnetic resonance (EPR) techniques. The photosensitization of TiO2 occurred practically from the exited triplet dye and the electron injection rate constant is 1.3×106 s−1. The influences of donor and acceptor on the electron injection were investigated.
Synthesis and structure of neutral double helicate
Authors: Su Xun‐Cheng , Zhou Zhi‐Fen , Zhu Shou‐Rong , Lin Hua‐Kuan , Weng Lin‐Hong , Leng Xue‐Bing , Chen Yun‐Ti
Published: September 2010

A new approach to generating supramolecular architectures, based on easy‐to‐prepare schiff base ligands, is described together with its application to the self‐assembly of supramolecular neutral double helicates.
Studies toward the synthesis of dienophile unit of methyl sartotuoate
Authors: Chen Xin‐Chao , Fan Chim‐Feng , Xu Xing‐Xiang
Published: September 2010

The preparation of C3‐C14 fragment of the dienophile unit of methyl sartotuoate is described. The key steps included Roush reaction and CuI catalyzed epoxy‐opening reaction of i‐PrMg‐Br.
Fluorescence quenching of anthracene by N, N‐diethylaniline in the O/W microemulsion
Authors: Guo Xia , Xu Hui , Guo Rong
Published: September 2010

Photoinduced electron‐transfer system of anthracene‐N, N‐diethylaniline (MA) was studied in the oil in water (O/W) microemulsions formed by SDS (sodium dodecyl sulfate), BA (benzyl alcohol) and H2O. The time‐resolved fluorescence study showed mat the fluorescence quenching of the excited anthracene by DEA occurs at the interface of the O/W microemulsions. Besides as the quencher of the excited anthracene, N, N‐diethylaniline could act as a cosurfactant to change the structures of the microemulsions, Just as BA did. The quenching rate constants for the different structures of the system were determined.
A theoretical study on the intermolecular interaction of energetic system—Nitromethane dimer
Authors: Li Jin‐Shan , Xiao He‐Ming , Dong Hai‐Shan
Published: September 2010

Three optimized geometries of nitromethane dimer have been obtained at the HF/6–31G* level. Dimer binding energies have been corrected for the basis set superposition error (BSSE) and the zero point energy. Computed results indicate that the cyclic structure of (CH3NO2)2 is the most stable of three optimized geometries, whose corrected binding energy is 17.29 kJ·mol−1 at the MP4SDTQ/6–31G*/HF/6–31G* level. In the optimized structures of nitromethane dimer, the inter‐molecular hydrogen bond has not been found; and the charge‐transfer interaction between CH3NO2 subsystems is weak; and the correlation interaction energy makes a little contribution to the intermolecular interaction energy of the dimer.
Theoretical studies on NLO properties of push‐pull multi‐cycle electro‐optical polymer intermediates including thiophene ring
Authors: Fu Wei , Feng Ji‐Kang , Yu Kun‐Qian , Ren Ai‐Min , Wang Jiang‐Hong , Shen Yu‐Quan
Published: September 2010

The second‐order nonlinear optical susceptibilities β, βμ, and third‐order non‐linear optical susceptibilities γ, 〈γ〉 of a series of the novel push‐pull multi‐ring electro‐photo polymer intermediates have been calculated. The influences of molecular structure, donor, acceptor and the frequency of external field on β and γ, and the relationship between γ and the number of thiophene rings (i. e. conjugated chain length) have been studied using INDO/SCI methods combined with sum‐overstate (SOS) formula. The calculated results show that γ is proportional to 2.69 power of the chain length of the conjugated molecular bonds when the length is not quite long.
Extraction of copper with p‐tert‐butyl‐calixarenes
Authors: Yang Yu‐Xiang , Shi Xian‐Fa , Ding Shi‐Chao , Chen Yu‐De , Xu Di‐Min , Chen Rang‐San
Published: September 2010

The extraction of copper with calixarenes was researched by comparing the results from calix[4]‐, calix[6]‐ and calix[8]‐arenes. The extraction ability increased as the order: calix [4]⇛ calix[8]⇛ calix[6]‐arenes, with the binding ratio being 1:1. The extraction mechanism was also discussed, and its equation Cu(NH3)42+ +H2L(0)→KexCu(NH3)4L(0) +2H+ and the extraction equilbrium constants (Kex) for calix[6]‐ and calix[8]‐arenes were obtained respectively.
Synthesis, characterization and magnetism of copper(II)‐lanthanide(III) heterobimetalic complexes with N, N'‐oxamidobis‐(benzoato)cuprate (II)
Authors: Li Yan‐Tuan , Yan Cui‐Wei , Zeng Xian‐Cheng , Liao Dai‐Zheng
Published: September 2010

Seven new μ‐oxamido copper(II)‐lanthanide(III) heterobimetalic complexes described by the formula Cu(obbz) Ln‐(Ph‐phen)2NO3(Ln = La, Nd, Eu, Gd, Tb, Ho, Er), where obbz denotes the oxamidobis(benzoato) and Ph‐phen represents 5‐phenyl‐1, 10‐phenanthroline, have been synthesized and characterized by the elemental analyses, spectroscopic (IR, UV, ESR) studies, magnetic moments (at room temperature) and molar conductivity measurement. The temperature dependence of the magnetic susceptibility of Cu(obbz)Gd(Ph‐phen)2NO3 complex has been measured over the range 4.2–300 K. The least‐squares fit of the experimental susceptibilities based on the spin Hamiltonian operator, Ĥ = −2 JŜ1·Ŝ2, yielded J= +1.28 cm−1, a weak ferromagnetic coupling, A plausible mechanism for a ferromagnetic coupling between Gd(III)‐Cu(II) is discussed in terms of spin‐polarization.
Lipophilicity determination of N‐( benzothiazol‐2‐yl )‐α‐amino alkyl phosphonic diesters by RP‐HPLC and RP‐HPTLC
Authors: Zhang Luig , Li Zai‐Guo , Huang Run‐Qiu , Wang Qin‐Sun
Published: September 2010

Using methanol‐water mixtures as the mobile phase, the chromatographic retention parameters k' and Rf were determined by reversed‐phase high‐performance liquid chromatography (RP‐HPLC) and reversed‐phase high‐performance thin‐layer chromatography (RP‐HPTLC) for N‐(benzothiazol‐2‐yl)‐α‐amino alkyl phosphoric diesters and the correlation with lipophilicity parameter (Clog P) was established. Log Kw values obtained from RP‐HPLC and Rm values obtained from RP‐HPTLC can be used to evaluate the lipophilicity of this kind of compounds. Chromatographic method is a good alternative for lipophilicity measurement.
Synthesis of indenyllanthanide amides: the effective initiators for polymerization of methyl methacrylate
Authors: Zhao Qun , Yao Ying‐Ming , Shen Qi
Published: September 2010

Diisopropylamido bisindenyl lanthanides (C9H7)2LnN(i‐Pr)2 (Ln=Gd(1), Y(2), Er (3)) were succesfully synthesized in satisfied yield by the reaction of Ln(N(i‐Pr)2)3(THF) with indene in 1:2 molar ratio in toluene. AH of the complexes exhibit very high catalytic activity in the polymerization of methyl methacrylate. The resulting polymers have narrow molecular weight distributions and high syndiotacticity.
A facile route for the syntheses of trisilanes containing C‐mono‐substituted carborane
Authors: Luo Yu‐Mei , Liu Fei , Wu Shi‐Hui
Published: September 2010

The syntheses of trisilanes containing C‐monosubstituted o‐carborane are described. The intermediate compund 2‐chloro‐2‐phenyl‐hexamethylsilane was prepared by elimination reaction between 2, 2‐diphenylhexamethyltrisilane and hydrogen chloride with a catalytic amount of aluminium chloride in chloroform solution.
Self‐assembly architecture of bis(guanidiniums) receptors incorporated by sulfate anions in single crystals
Authors: Lu Guo‐Yuan , Song Wd , Tang Feng , Jin Chuan‐Min , Liu Fang , Wan Xiao‐Bin
Published: September 2010

A novel bis(guanidiniums) receptor for the catalytic cleavage of phosphosdiester was prepared and self‐assembly architecture through hydrogen bonds and electrostatic interactions among the bis(guanidiniums) receptor, the sulfate anion and water molecule was revealed by X‐ray crystallographic analysis.
Photolysis of oxygen saturated ethers in the presence of Sn(II) or Cu(II) salts
Authors: Shi Min
Published: September 2010

Photolysis of diethyl ether‐oxygen charge transfer complex in the presence of Sn(II) or Cu(II) salts gave higher yields of the oxidation products, ethyl acetate, acetaldehyde, ethanol, ethyl formate and methanol compared with those without the salts. In addition, the photolysis of an oxygen saturated tetrahydrofuran (THF) or dibutyl ether solution gave γ‐butyrolactone or butanol and butyl butyrate as major products with small amounts of undetermined compounds, respectively. Their yields were also affected by the addition of Cu(II) or Sn(II) salts.
Oxidative Coupling of Methane over W‐Mn/SiO2 Catalyst
Authors: Li Shu‐Ben
Published: September 2010

W‐Mn/SiO2 catalyst has been developed in our laboratory (LICP), which is active, selective and stable for oxidative coupling of methane (OCM) in fixed bed and fluidized bed reactors. The research results have been reproduced at different reaction conditions by two groups of J. H. Lunsford (JH‐LL) from Texas A & M University and R. M. Lambert (RMLL) from University of Cambridge respectively. The basic research aspects on this catalyst systems, reaction performances, structure characterization and reaction mechanism were reviewed. A model on two active sites related to W6+/5+ and Mn3+/2+ has been suggested for activation of methane and oxygen respectively.
Enantiocontrol in Macrocycle Formation from Catalytic Metal Carbene Transformations
Authors: Doyle Michael P. , Hu Wen‐Hao
Published: September 2010

The development of catalytic metal carbene transformations for the construction of macrocyclic lactones has dramatically increased their synthetic advantages. This is the first review of this Developing methodology.

The research described in this review has been supported by the National Science Foundation, National Institutes of Health, and the Petroleum Research Fund of the American Chemical Society.
Synthesis of Some Novel Amino Phenols with Octahydro‐1,1′‐binaphthyl Backbone
Authors: Guo Hui , Wang Yi , Ding Kui‐Ling
Published: September 2010

A series of new octahydro‐1,1′‐binaphthyl derivatives, namely (R)‐(+)‐2‐(N, N‐dialkylamino)‐2′‐hydroxy‐5,5′,6,6′,7, 7′,8,8′‐octahydro‐1,1′‐binaphthyls (7,9), have been synthesized. Their asymmetric induction for enantioselective addition of Et2Zn to benzaldehyde was examined and it was found that (R)‐(+)‐2‐(N‐cyclohexyl‐N‐methylamino)‐2′‐hydroxy‐5, 5′,6,6′,7,7′,8,8′‐octahydro‐1,1′‐binaphthyl (9c) exhibited the best asymmetric induction among the ligands prepared, up to 55% ee of 1‐phenylpropanol being obtained.
1‐Dodecene Hydroformylation Catalyzed by Water Soluble Rhodium Phosphine Complex in Two‐Phase System
Authors: Li Yao‐Zhong , Chen Hua , Chen Jun‐Ru , Cheng Pu‐Ming , Hu Jia‐Yuan , Li Xian‐Jun
Published: September 2010

1‐Dodecene hydroformylation catalyzed by water soluble rhodium complex [RhCl(CO) (TPPTS)2] was studied in the presence of TTPTS [P(m‐C2H4SO3Na)3] and CTAB (cetyltrimethyl ammonium). The influence of reaction parameters was discussed in detail based on micelle effect in biphasic system. The modification for the microcircumstance of micelle interface was conducted by the introduction of a catalyst promoter TPPDS [PhP(m‐C2H4SO3Na)2] into the reaction solution. A synergistic effect between TPPDS and TPPTS on the regioselectivity of 1‐dodecene hydroformylation was observed. The selectivity of linear aldehyde in the products was so high as 95.7% at the molar ratio of [TPPDS]/[TPPTS] = 0.5.
Catalysis for One‐step Synthesis of Dimethyl Ether from Hydrogenation of CO
Authors: Zheng Xiao‐Ming , Fei Jin‐Hua , Hou Zhao‐Yin
Published: September 2010

In this paper, a new catalyst system Cu‐Mn‐(M)/γ‐Al2O3 was developed for the directly synthesis dimethyl ether (DME) from synthesis gas in a fixed‐bed reactor. The catalysts with different n (Cu) : n (Mn) ratios, several promoter M (M is one of Zn, Cr, W, Mo, Fe, Co or Ni) were prepared and tested. The results showed the catalysts have a high conversion of CO and a high DME selectivity. The DME yield in tail gas reached 46.0% (at 63.27% conversion of CO) at 2.0 MPa, 275°C, 1500 h−1 with the Cu2Mn4Zn/γ‐Al2O3 catalyst.
An Unusual Variation of Surface Tension with Concentration of Mixed Cationic‐anionic Surfactants
Authors: Xiao Jin‐Xin , Bao Yan‐Xia
Published: September 2010

There are two platforms in the surface tension vs. concentration curve (γ‐lgC curve) of cationic‐anionic surfactant mixtures. The first platform is the same as that of common surfactant solution, and the cross point is the CMC. After the CMC, the mixtures form precipitate. At higher concentration, the mixtures form homogeneous solution again. When the mixtures form homogeneous solution at high concentration, surface tension increases with concentration, then becomes constant. So the γ‐lgC curve exhibits the second platform. The surface tension at the second platform increases by increasing molar ratio of two surfactants and polar group size of surfactants, and decreases with adding inorganic salts.
Photosensitization of Nanocrystalline TiO2 Electrode Modified with C60 Carboxylic Acid Derivatives
Authors: Zhang Wen , Shi Ya‐Ru , Gan Liang‐Bing , Huang Chun‐Hui , Wang Yan‐Qin , Cheng Hu‐Min
Published: September 2010

C60 carboxylic acid derivatives can be readily adsorbed on the surface of nanocrystalline TiO2 film. The C60 carboxylic acids adsorbed on nanocrystalline TiO2 films act as charge‐transfer sensitizer. The electron transport from TiO2 to the C60 derivatives results in the generation of the cathodic photocurrent. The short‐circuit photocurrent of a C60 tetracarboxylic acid is 0.45 μA/cm2 under 464 nm light illumination. The photoelectric behaviour of ITO electrodes modified by the same C60 carboxylic acids is different from that of the modified TiO2 electrodes, and shows anodic photocurrent.
A Novel Domino Reaction of 1, 1'‐bi‐2‐Naphthol Catalyzed by Copper (II)‐amine Complexes
Authors: Tan Duan‐Ming , Li Hui‐Hua , Wang Bo , Liu Han‐Biao , Xu Zun‐Le
Published: September 2010

1,1′‐Bi‐2‐naphthol (1) was oxidized into q‐oxo‐13c‐alkyloxy‐l,13c‐dihydro‐dibenzo [a,kl]‐xanthenes (2–11) with high isolated yields (58–94%) in alcohol solvents under the catalysis of copper(II)‐amine complexes in the presence of oxygen. The conversion of 1 to 2–11 belongs to Domino‐reaction.
Highly Enantioselective Microbial Hydrolysis of cis‐2‐Arylcyclopropanecarbonitriles
Authors: Feng Guo‐Qiang , Wang Mei‐Xiang
Published: September 2010

Hydrolysis of racemic cis‐2‐arylcyclopropanecarbonitriles catalyzed by Rhodococcus sp. AJ270 whole cells proceeded enantioselectively to afford the corresponding amide and acid with enantiomeric excess higher than 99%.
Application of Sm0/Auxiliary and Sm0/MCln System in Organic Synthesis
Authors: Zhang Yong‐Min , Liu Yun‐Kui
Published: September 2010

Application of Sm0/auxiliary and Sm0/MCln system in organic synthesis was reviewed.
A Novel Way to Prepare TiO2 and γ‐Al2O3 Supported Catalysts with Large Surface Areas
Authors: Zhu Yue‐Xiang , Zhao Bi‐Ying , Zhou Chang‐Jun , Wang Rong‐Qiu , Xie You‐Chang
Published: September 2010

Several TiO2 and γ‐Al2O3 supported catalyst systems were prepared by a novel way and characterized by X‐ray diffraction, Raman spectroscopy and BET surface area measurement. The results show: (1) all the samples, including MoO3/TiO2, WO3/TiO2, V2O5/TiO2, FeSO4/γ‐Al2O3, Al2 (SO4)3/γ‐Al2O3, K2CO3/‐Al2O3 and so on, prepared by impregnating TiO2·H2O or pseudo‐boehmite AlO(OH) with the active components then calcining at a high temperature exhibit much larger surface areas than that of pure TiO2 or γ‐Al2O3 calcined at the same temperature; (2) the surface area of the sample increases with the increase in the coverage of active component on the surface of the support; (3) when the content of active component reaches its utmost monolayer dispersion capacity, the surface area of the sample is the largest, and then decreases when the content of active component exceeds its dispersion threshold.
Hydrotrope‐Solubilization Action of Urea in CTAB/n‐C5H11‐OH/H2O System
Authors: Guo Rong , Zou Ai‐Hua , Yang Han‐Min
Published: September 2010

Urea can enhance the aqueous solubility of surfactant CTAB (hexadecyltrimethylammonium bromide) when it shows the hydrotrope action. It will show the hydrotrope‐solubilization action when the solubilized amount of n‐C5H11OH in O/W microemulsion and that of water in W/O microemulsion are increased. The mechanism of the hydrotrope‐solubilization action of urea is the increase of the stability of W/O and O/W microemulsion and structural transition from the lamellar liquid crystalline phase to the bicontinuous structure.
Supramolecular Complexation Behavior of Novel Cyclotriveratrylene Derivatives with Benzoate Pendants with C60
Authors: Zhan Hao‐Qiang , Jiang Xi‐Kui , Li Zhan‐Ting
Published: September 2010

Four novel cyclotriveratrylene (CTV) derivatives with three benzoate pendants bearing different aliphatic chains have been prepared in good yields, starting from CTV. The complexation behavior of these CTV derivatives towards C60 in arene solvents has been measured by UV‐visible spectroscopy and high complexation constants are obtained. It is observed that the complexation is promoted pronouncedly by introducing methyl ester groups to the aromatic pendants, while this promoting effect is reduced when the methyl groups are replaced by longer alkyl groups.
EPR Study on the Complex Formed by Charge‐Transfer Process between Ground‐state Acceptor 2, 3‐Dicyano‐5, 6‐dichloro‐1, 4‐benzoquinone and Some Donors and on Cation Radical of Perylene (or Pyrene)
Authors: Shi Ji‐Liang , Zhou Cheng‐Ming , Zhao Xin , Xu Jia‐Yi , Jiang Xi‐Kui
Published: September 2010

EPR study showed that the semi‐quinone radical anion of 2,3‐dicyano‐5,6‐dichloro‐1,4‐benzoquinone (DDQ) was formed in a charge transfer process between ground‐state DDQ as acceptor and each one of following ground state donors, i.e., 4‐methyl‐4′‐tridecyl‐2, 2′‐bipyridyl; 4‐methyl‐4′‐nonyl‐2, 2′‐bipyridyl; bis (2,2′‐bipyridyl) (4‐methyl‐4′‐heptadecyl‐2, 2′‐bipyridyl)ruthenium(2+) perchlorate and perylene. EPR study also showed that there are perylene cation radical and pyrene cation radical in the following experimental conditions: (a) in 98% sulfuric add. (b) 10−3 mol/L perylene (or pyrene) was dissolved in trifluoroacetic acid‐nitrobenzene (1: 1 V/V).
Asymmetric Photochemical Synthesis of Chiral 5‐(R)‐(l)‐Menthyloxy‐4‐Cycloaminobutyrolactones
Authors: Wang Zhao‐Yang , Jian Tian‐Ying , Chen Qing‐Hua
Published: September 2010

Through photocatalysed regiospecific and stereoselective additions of cycloamines to 5‐(R)‐(l)‐menthyloxy‐2 (5H)‐furanone (3), chiral 5‐(R)‐(l)‐menthyloxy‐4‐cycloaminobutyrolactones were synthesized. In the new asymmetric photoaddition of compound 3, the N‐methyl cyclic amines (4) gave novel chiral CC photoadducts (5) in 24–50% isolated yields with d. e. ≥ 98%. However, the secondary cyclic amines (6) afforded optically active NC photoadducts (7) in 34–58% isolated yields with d. e. ≥ 98% under the same condition. All the synthesized optically active compounds were identified on the basis of their analytical data and spectroscopic data, such as [α]58920, IR, 1H NMR, 13C NMR, MS and elementary analysis. The photosynthesis of chiral butyrolactones and its mechanism were discussed in detail.