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Approach to synthesis of novel chiral 3-chloro-2.5H)- furanone and its application in asymmetric reactions

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Chinese science Bulletin 2000年第8期45卷 711-716页

作者： HUANG Hui & CHEN Qinghua1. department of chemistry, Tonghua {2.’s College, Tonghua 134002. China 2. department of chemistry, Beijing Normal university, Beijing 100875, China department of chemistry Tonghua Teacher’s College Tonghua China department of chemistry Beijing Normal University Beijing China

The synthetic method of the novel chiral synthon, 5-/-menthyloxy-3-chloro-2.(5H)-furanone 5a and its application in asymmetric reactions were investigated. 5a is easily obtained in highly optical purity, and acts as a stable acceptor of Michael addition with oxygen nucleophiles in tandem double Michael addition / internal nucieophilic substitution to offer the spiro-cyclopropane derivative containing four stereogenic centers 8, which it is difficult to obtain by routine methods. The synthetic methods for 5a and 8 are reported in detail and the new compounds are identified on the basis of their analytical data and spectroscopic data, such as UV, IR, H NMR,13 C NMR, Ms and elementary analysis. The absolute configuration of the interesting spiro-cyclopropanes, spiro [1-chloro-4-(/-menthyloxy)-5-oxo-6-oxa-biscyclo[3.1.0]hexane-2.3i(4’-/-menthyloxy-5’-/-menthyloxy- butyrolactone)] 8 was established by X-ray crystallography. This result can provide important synthetic strategy in synthesis of some complex

关键词： new chiral synthon. 5-l-menthyloxy-3-chloro-2.(5H)-furanone absolute configuration spiro-cyclopropane derivative containing multiple chiral centers.

Resolution of α-cyclohexyl-mandelic acid enantiomers by two-phase (O/W) recognition chiral extraction

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science China chemistry 2007年第6期50卷 764-769页

作者： TANG KeWen1,2. ZHANG GuoLi2. HUANG KeLong2. LI Yuanjian3 & YI JianMin1,2.1 department of chemistry and {2. engineering, Hunan Institute of science and Technology, Yueyang 414000, China 2.College of chemistry and {2. engineering, Central south university, Changsha 410083, China 3 College of Pharmaceutical science, Central south university, Changsha 410078, China department of chemistry and {2. engineering Hunan Institute of Science and TechnologyYueyang 414000China College of chemistry and chemical {2. Central South UniversityChangsha 410083China

This paper presents a new chiral separation technology:two-phase(O/W)recognition chiral *** behavior of alpha-cyclohexyl-mandelic acid enantiomers was studied in the extraction system with D(L)-isobutyl tartrate in 1,2.dichloroethane organic phase and beta-CD derivatives in aqueous phase,and the influence of the kind and concentration of extractant and pH on extraction performance was *** experimental results indicate that two-phase(O/W)recognition chiral extraction is of strong chiral separation ***-^-CD,HE-beta-CD and Me-beta-CD have higher recognition ability for s-CHMA than that for R-CHMA,among which HP-beta-CD has the strongest ability;whereas,D-isobutyl tartrate has reversed recognition ability for *** the extraction system containing HP-beta-CD and D-isobutyl tartrate,e.e.% of s-CHMA in aqueous phase reached 2..6% by one stage extraction,and the distribution ratio for R-CHMA(k_R)and for s-CHMA(k_s)and separation factor(alpha)are 2.44,0.89 and 2.49,***,pH and concentration of extractant have great effects on chiral separation ***-phase(O/W)recognition chiral extraction has great significance for preparative separation of racemic compounds.

关键词： two-phase(W/0)recognition chiral extraction alpha-cyclohexyl-mandelic acid enantiomers

Effects of water phase concentration on the emulsion polymerization of polyaniline

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Journal of Central south university of Technology 2001年第2期8卷 140-142页

作者： PAN Chun yue 1,CHEN Zhen hua 2.HUANG Yong li 1,HUANG Ke long 1 (1.College of chemistry and chemical {2., Central south university, Changsha 410083, China 2.department of Materials science and {2., Central south university, Cha 1. College of chemistry and chemical {2. Central South University 410083 Changsha China 2. department of Materials science and engineering Central South University 410083 Changsha China

The emulsion polymerization of aniline in three phase system of xylene functionalized protonic acid water was carried out using (NH 4) 2. 2. 4 as oxidant. The influences of water phase concentration on the viscosity, conductivity, transmittance of polyaniline(PAN) latex and its powders were studied. The results show that the properties of PAN prepared through the emulsion polymerization are influenced by the amount of water used in the polymerization. The morphology of PAN varies with the water phase concentration used in the polymerization, which may result in the change of properties of PAN latex and its powders. When the volume fraction of water (φ) is about 2.% 30%, the prepared PAN powder has higher conductivity, and the PAN latex has appropriate viscosity and particle size. The consumption of xylene was reduced at high φ value.

关键词： polyaniline emulsion polymerization water concentration property

supporting of Nickel(Ⅱ) Acenaphthenediimine with Free Amino Group for Ethylene Polymerization

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Journal of Wuhan university of Technology(Materials science) 2010年第2期25卷 260-264页

作者：胡扬剑 department of chemistry and {2. engineering Huaihua College

Bis （4-（4-amino-3, 5-diethylbenzyl）-2. 6-diethylphenylimino） acenaphthene] di- chloronickel （NiLCl2. was prepared and supported on siO2.modified by methyl trichlorsilane（s-1） and on siO2.MgCl2.TiCl4 （s-2. respectively. Two supported catalysts s-1 and s-2.used as catalysts for ethylene polymerization were studied and the influences of various polymerization conditions, including the polymerization temperature, cocatalysts, Al/Ni molar ratio on the catalytic activity, branching degree and branch length of PE were also investigated. The experimental results show that the supported catalysts exhibit higher catalytic activity for ethylene polymerization, the highest catalytic activity of s-1 using AlEt2.l as cocatalyst at 50 ℃, reaching 5.8×10^5gPE/molNi·h, and needed lower Al/Ni molar ratio compared to homogeneous analogue.

关键词： nickel diimine complex supported catalyst branched polyethylene diethylaluminium chloride

Biological decomposition of Na_2._2._3 into sulfur by a newly isolated facultative thermophilic alkaline desulphuricant strain

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science China chemistry 2009年第2期52卷 226-230页

作者： ZHANG JianBin1,ZHANG Tong2.MA Kai2.ZHANG PengYan2.LI Qiang2.& WEI XiongHui1 1 department of Applied chemistry,College of chemistry & Molecular engineering,Peking university,Beijing 100190,China 2.College of chemical engineering,Inner Mongolia university of Technology,Huhhot 010051,China 1. department of Applied chemistry College of Chemistry & Molecular Engineering Peking University Beijing 100190 China 2. College of chemical engineering Inner Mongolia University of Technology Huhhot 010051 China

A facultative thermophilic alkaline desulphuricant strain named GDJ-3 was isolated from neutral soils,enriched on sulfur synthetic medium,and detected in previous *** and chemotax-onomic analyses and 16s RNA gene sequencing showed that the strain was in good agreement with Alpha proteobacterium sp.(97%) and ochrobactrum sp.(98%).The regenerative processes of the solu-tion containing sulfur compounds(sCs) from the strain through an orthogonal test were investigated to get the optimum regenerative *** results showed that regenerative temperature,air flow,and stirring speed of the agitator were the main three variables influencing the regenerative processes of the *** optimum regenerative efficiency of the sCs from the strain was obtained when tem-perature,air flow,and stirring speed of the agitator were 318.2.K,3.0 L/min,and zero r/min,*** this condition,when the cell concentration of the strain was adjusted to 107/mL,the concentra-tions of Na2.2.3 and Na2. in the sCs decreased from 112.68 g/L to 96.88 g/L and from 0.87 g/L to 0.11 g/L in 9.5 ***,XRD spectrum shows that sulfur was formed in the regeneration *** results suggest that the strain has potential application to the regeneration of the industrial so-lution containing sulfur compounds.

关键词： bio-desulfurization thermophiles optimization biocomposition orthogonal test

studies on photo-electro-chemical catalytic degradation of acid scarlet 3R dye

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science China chemistry 2005年第4期48卷 297-304页

作者： LI Mingyu1,XIONG Lin1,CHEN Yunyun2.ZHANG Na1,ZHANG Yuanming2.& YIN Hua1 1.department of Environmental engineering,Jinan {2.,Guangzhou 510630,China 2.department of chemistry,Jinan {2.,Guangzhou 510630,China 1. department of Environmental engineering Jinan University 510630 Guangzhou China 2. department of chemistry Jinan University 510630 Guangzhou China

A new type of photo-electro-chemical catalytic reactor was *** and anode of the new reactor were made of high-purity graphite and titanium dioxide electrode re-spectively.A saturated calomel electrode (sCE) was used as the reference *** the condition of ultraviolet radiation and anodic bias-voltage,acid scarlet 3R was degraded by the process of photoelectrocatalysis with titanium dioxide electrode in anodic compartment,while it was degraded by electrogenerated Fenton’s reagent and hydrogen peroxide through reducing dissolved oxygen with graphite electrode in *** new reactor made the best use of photogenerated holes and photogenerated charge on the anode of the new reactor,which achieved the purpose of degrading acid scarlet 3R in the cathodic and anodic compartments simultaneously,i.e.“two electrodes and double effect”.The experimental results showed that,compared with other photoelectrocatalysis reactors (“two electrodes and single effect” reactor),the new reactor has obviously enhanced the degradation of acid scarlet 3R *** the con-centration of the dye being 30 mg·L?1 in water,under the operating conditions that when the inert supporting electrolyte concentration was 0.02.mol·L?1 sodium sulfate,initial solution pH = 3,and cathodic potential ?Ec = 0.66 V,the highest decolorizing efficiency of 92. was accomplished in cathodic compartment,and that of 60% in anodic compartment.

关键词： photo-electro-chemical catalysis, graphite electrode, photoelectrocatalysis, acid scarlet 3R.

Molecular dynamics simulations on the structures and properties of ε-CL-2.-based PBXs ——Primary theoretical studies on HEDM formulation design

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science China chemistry 2007年第6期50卷 737-745页

作者： XU XiaoJuan1,2. XIAO JiJun1, HUANG Hui3, LI Jinshan3 & XIAO HeMing1 1 department of chemistry, Nanjing {2. of science and Technology, Nanjing 2.0094, China 2.department of chemistry, Yancheng teacher’s College, Yancheng 2.4002. China 3 Institute of chemical Materials, China Academy of engineering Physics, Mianyang 62.900, China department of chemistry Nanjing University of Science and TechnologyNanjing 210094China department of chemistry Yancheng Teacher''s CollegeYancheng 224002China Institute of chemical Materials China Academy of Engineering PhysicsMianyang 621900

Five polymer bonded explosives(PBXs)with the base explosive epsilon-CL-2.(hexanitrohexaazaisowurtzi-tane),the most important high energy density compound(HEDC),and five polymer binders(Estane 5703,GAP,HTPB,PEG,and F_(2.14))were *** dynamics(MD)method was employed to investigate their binding energies(E_(bind))safety,mechanical properties,and energetic *** information and rules were reported for choosing better binders and guiding formulation design of high energy density material(HEDM).According to the calculated binding energies,the ordering of compatibility and stability of the five PBXs was predicted as epsilon-CL-2./PEG silon-CL-2./ Estane5703 ≈ epsilon-CL-2./GAP silon-CL-2./HTPB silon-CL-2./F_(2.14).By pair correlation function g(r)analyses,hydrogen bonds and vdw are found to be the main interactions between the two *** elasticity and isotropy of PBXs based epsilon-CL-2. can be obviously improved more than pure epsilon-CL-2. *** is not by changing the molecular structures of epsilon-CL-2. for each binder to affect the *** safety and energetic properties of these PBXs are mainly influenced by the thermal capability(C_p^(deg))and density(p)of binders,respectively.

关键词： high energy density material (HEDM), hexanitrohexaazaisowurtzitane (CL-2.), polymer bonded explosives (PBXs), molecular dynamics (MD), compatibility, safety properties, mechanical properties, energetic properties

A whisker-like carbon composite for the immobilization of laccase and its bioelectrochemistry

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science China chemistry 2010年第6期53卷 1332-1336页

作者： MA GuoXian1,2.ZHONG QingDong2.& LU TianHong3 1department of chemical {2.,shanghai Institute of Technology,shanghai 2.02.3,China 2.chool of Materials science and {2.,shanghai university,shanghai 2.0072.China 3department of chemistry,Nanjing Normal university,Nanjing 2.0097,China 1. department of chemical {2. Shanghai Institute of Technology Shanghai 200233 China2. School of Materials Science and Engineering Shanghai University Shanghai 200072 China3. Department of Chemistry Nanjing Normal University Nanjing 210097 China

A novel mesoporous carbon/whisker-like carbon (MCWC) composite was used for the immobilization of laccase (Lac) and its bioelectrochemical behaviors were *** was confirmed by XPs that Lac was strongly adsorbed on the surface of the MCWC *** cyclic voltammetric results showed that the immobilized Lac underwent a direct quasi-reversible electrochemical *** value of the electron transfer rate constant ks was estimated to be 0.770 s-1,indicating a reasonably fast electron transfer between the immobilized Lac and the underlying *** surface concentration (I-) of Lac was estimated to be 2.730 × 10-12.mol/*** experimental results showed that the immobilized Lac displayed an appreciable electrocatalytic activity to the electrochemical reduction of *** properties could be attributed to the particular structure of loosely packed nanometer-scale carbon whiskers and the existence of a large amount of oxygen-containing *** immo- bilization method and the novel carrier (MCWC) may find new applications in fabricating the biocatalysts for biofuel cells.

关键词： laccase whisker-like carbon composite direct electrochemical reaction oxygen bioelectrochemistry

structure and Pozzolanic Activity of Calcined Coal Gangue during the Process of Mechanical Activation

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Journal of Wuhan university of Technology(Materials science) 2009年第2期24卷 326-329页

作者：郭伟 department of Material engineering Yancheng Institute of Technology Institute of Material science and engineering Nanjing University of Technology

On the basis of analyzing coal gangue＇s chemical and mineral compositions, the structure change of coal gangue during the mechanical activation was investigated by XRD, FTIR, NMR, and the mechanical strength of the cement doped coal gangue with various specific surface area was tested. The experimental results indicate that, the lattice structure of metakaolin in coal gangue samples calcined at 700 ℃ disorganizes gradually and becomes disordered, and the lattice structure of α-quartz is distorted slightly. The pozzolanic activity of the coal gangue increases obviously with its structural disorganization.

关键词： coal gangue mechanical activation structure NMR tetrahedron