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Theoretical study on thermal decomposition of azoisobutyronitrile in ground state

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Science china chemistry 2004年第5期47卷 373-380页

作者： SUN Chengke1,2, ZHAO Hongmei1 & LI Zonghe1 1. department of chemistry, Beijing normal University, Beijing 100875, china 2. department of chemistry, qujing normal College, qujing 655000, china 1. department of chemistry Beijing Normal University 100875 Beijing China 2. department of chemistry Qujing Normal College 655000 Qujing China

The thermal decomposition mechanisms of azoisobutyronitrile (AIBN) in the ground state have been investigated systematically. Based on the potential energy surfaces (PES) of various possible dissociation paths obtained using the semiempirical AM1 method with partial optimization, the density function theory B3LYP/6-311G* method was employed to optimize the geometric parameters of the reactants, the intermediates, the products and the transition states, which were further confirmed by the vibrational analysis. The obtained results show that the re- action process of the two-bond (three-body) simultaneous cleavage Me2(CN)C─ N=N─ C(CN)Me2? 2Me2(CN)C?+N2 is much more favorable than the reaction process of the two one- bond asynchronous cleavage Me2(CN)CN=N─C(CN)Me2 ? Me2(CN)CN=N?+ Me2(CN)C?? Me2(CN)C?+ N2. It was suggested that the electron shrinking effect of double bond (─N=N─) in AIBN and the stabilities of the Me2(CN)C?radical as well as N2 molecule are main factors of leading to the reaction proceeding in the former pathway. The calculation results were consistent with all the experimental facts.

关键词： azoisobutyronitrile, radicals, thermal decomposition, density function theory (DFT).

Kinetic model of transesterification of diphenyl carbonate and 1,4.butyldiol

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Journal of Natural Gas chemistry 2010年第4期19卷 436-440页

作者： Liping Wang1,2,3,4.Bin Xiao1,2,4.Gongying Wang1,2 1.Chengdu Institute of Organic chemistry,Chinese Academy of Science,Chengdu 61004.,Sichuan,china 2.Changzhou Key Laboratory of Green and Technology,Changzhou Institute of chemistry,Changzhou 213164.Jiangsu,china 3.{4. of chemistry,qujing normal College,qujing 655000,yunnan,china 4.Graduate School of Chinese Academy of Science,Beijing 100039,china [a] Chengdu Institute of Organic chemistry Chinese Academy of Science Chengdu 610041 Sichuan China [b] Changzhou Key Laboratory of Green and Technology Changzhou Institute of Chemistry Changzhou 213164 Jiangsu China [c] Department of Chemistry Qujing Normal College Qujing 655000 Yunnan China [d] Graduate School of Chinese Academy of Science Beijing 100039 China

The transesterification of diphenyl carbonate （DPC） with 1,4.butyldiol （BD） was kinetically investigated in the presence of lithium acetate catalyst at 4.5 *** reaction was followed by the measurement of the quantity of phenol which was distilled from the *** experiments supported the assumption that the phenyl ester groups in DPC and phenyl hdroxybutyl carbonate （PHBH） had the same reactivity,and the transesterification obeyed first-order kinetics with respect to DPC and BD,and a rate equation was *** reaction rate was found to be first order with respect to the catalyst concentration as *** those data were incorporated in the rate equation,excellent agreement between calculated values and the observed ones was recognized over a wide range.

关键词： transesterification diphenyl carbonate 1,4.butyldiol lithium acetate kinetics

ADSORPTION OF GALLIUM WITH N_503LEVEXTREL RESIN

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中国有色金属学会会刊：英文版 1994年第3期4卷 36-40页

作者： Chen, Jianrong Hu, Jianhua Peng, Chaoqun(department of chemistry,Zhe jiang normal University,Jinhua 32100 4.

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关键词： gallium adsorption N503 levextrel resin

Synthesis and Crystal Structure of CoCl(ieaa)(C_(10)H_7-ieai)(C_(10)H_7NH_2)

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Chinese Journal of Structural chemistry 2002年第1期21卷 22-25页

作者： FENG Yun-Long (department of chemistry, Zhejiang normal University Jinhua 231004.china) department of chemistry Zhejiang Normal University Jinhua 231004

The title complex CoCl(ieaa)(C10H7-ieai)(C10H7NH2), C32H32ClCoN4.7, Mr= 679.00; (ieaa- and C10H7-ieai- are the anions of isonitrosoethylacetoacetate and its N-a- naphthylamine derivative of Schiff base, respectively, C10H7NH2 is a-naphthylamine), crystallizes in the monoclinic system, space group P21/n with a=11.84.(2), b=23.912(5), c=12.783(3)? b=116.54.3), V=3239(1)?, Dc=1.392g/cm3, F(000)=14.8, Mr=679.00, m(MoKa)=0.665mm-1, Z=4. final R=0.0584.and wR=0.1388 for 4.77 observed reflections (I ≥ 2s(I)). A nitrogen atom of the ieaa- ligand and two nitrogen atoms of the C10H7-ieai- ligand define one of the triangular faces in the distorted octahedral geometry about the cobalt atom. The title complex contains isonitroso-b-ketoimine.

关键词： cobalt complex isonitroso-b-ketoimine Schiff base crystal structure

Origin of the Red Earth sequence on the northeastern Tibetan Plateau and its implications for regional aridity since the middle Miocene

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Science china Earth Sciences 2006年第5期49卷 505-517页

作者： WANG Xianyan1,7, LU Huayu1,2, JI Junfeg3, WANG Xiaoyong1,7, ZHAO Jingbo4. HUANG Baochun5 & LI Zhen6 1. SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710075, china 2. department of Urban and Resources Sciences, Nanjing University, Nanjing 210093, china 3. department of Earth Sciences, Nanjing University, Nanjing 210093, china 4. department of Geography, Shaanxi normal University, Xi’an 710062, china 5. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, china 6 department of Geography, Qinghai normal University, Xining 810008, china 7. Graduate School of the Chinese Academy of Sciences, Beijing 100039, china 1. SKLLQG Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China 7. Graduate School of the Chinese Academy of Sciences Beijing 100039 China 2. department of Urban and Resources Sciences Nanjing University Nanjing 210093 China 3. department of Earth Sciences Nanjing University Nanjing 210093 China 4. department of Geography Shaanxi Normal University Xi’an 710062 China 5. Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China 6. department of Geography Qinghai Normal University Xining 810008 China

The Red Earth deposit around Xining, northeastern Tibetan Plateau, has beenstudied in terms of soil micro-structure, grain-size distribution, major- and trace-elementchemistry and magne-tostratigraphy. Field investigations indicate that the Red Earth sequenceconsists of 25 visually definable yellow-brown and weakly-developed soils interbedded with reddishstrongly-developed soils, and has a similar structure to the aeolian Red Clay deposit on the ChineseLoess Plateau. Grain-size analysis shows that the Red Earth deposit is very fine-grained with anegligible sand fraction ( > 63 μm). Thin-section observations under light microscopy show that thedeposit has a clayey texture and the coarse fraction ( > 10 μm) mainly consists of quartz,feldspar and micas. Pyroxene and hornblende were also observed. This mineralogical composition ofthe coarse fraction is similar to that of the Quaternary loess. In addition, all of the mineralgrains are semi angular semi-angular and are generally finer than 63 μm. There is a good agreementbetween the major and minor trace element chemistry of loess-soil units and the Red Earth *** REE distributions of the loess-soil and the Red Earth deposit are similar in shape, withenriched LREE and fairly flat HREE profiles and a clear negative Eu anomaly. The geochemicalcharacteristics of the Red Earth deposit are also identical to those of upper continental crust,thus indicating a wind-blown origin. Magnetostratigraphic investigation shows that onset of the RedEarth deposition predates 11.4.Ma BP (13.6 Ma at a nearby site). The distribution of the reportedMiocene aeolian loess at Qin''an of the Loess Plateau is still unknown. Our results indicate thatthis aeolian deposit had extended to the northeastern Tibetan Plateau by at least the middleMiocene. The similarity of the element geochemistry between the Red Earth deposit and the overlyingloess shows that they may have similar sources and dynamic transport system, and may indicate thatthe

关键词： Red Earth deposit, Northeastern Tibetan Plateau, aeolian deposit, aridity of Asia, the middle Miocene.

Molecular orbital study on antiferromagnetic coupling mechanism in a silver (I) complex

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Science Bulletin 2005年第18期 33-38页

作者： ZHANG Guiqin1,2, HUANG Jiangen1,3, HUANG Yuanhe1, FANG Decai1 & ZHANG Deqing4.1. department of chemistry, Beijing normal University, Beijing 100875, china 2. department of Physics, qujing normal College, qujing 655000, china 3. department of chemistry, Jinggangshan College, Ji’an 34.009, china 4. Organic Solids Laboratory, Center for Molecular Sciences, Institute of chemistry, Chinese Academy of Sciences, Beijing 100080, china

The mechanism of antiferromagnetic coupling in an Ag (I) complex of nitronyl nitroxide is investigated by means of the broken-symmetry approach within the density functional method (DFT-BS). The magneto-structural corre-lation and the single-occupied molecular orbital (SOMO) analysis reveal the existence of the antiferromagnetic cou-pling pathway along nitronyl nitroxide units via Ag (I) ion, and that the Ag (I) ion plays an important bridge role. The spin population analysis also shows the existence of spin de-localization along the ONCNO-Ag-ONCNO chain. It is found that the non-typical covalent bonds with major ionic charac-ter between Ag (I) ions and oxygen atoms of nitronyl nitrox-ide units can be used to mediate the spin-spin interaction of nitronyl nitroxides.

关键词： nitronyl nitroxide Ag (I) complex antiferromagnetic coupling density function theory molecular orbital method.

The Nature of Bonding in IrC

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Chinese Chemical Letters 1998年第12期9卷 0-0,0-0页

作者： Xiao Guang XIE Huai CAO (Modem Biological Center, yunnan University, Kunming 650091)Xian Jun BI (department of chemistry, yunnan {4. University, Kunming 650092)Shu Shan Dai (department of chemistry, yunnan University, Kunndng 650091) yunnan Univ Modern Biol Ctr Kunming 650091 Peoples R China yunnan normal Univ Dept Chem Kunming 650092 Peoples R China yunnan Univ Dept Chem Kunming 650091 Peoples R China

The nature of bonding in the title compound has been stUdied by using CASSCF andFOCI techniques. The ground state of IrC has been found to be 2△ arising primarilyfrom:.. 1σ2 2σ2 1π4.1δ3 3σ2 configuration, which forms a triple bond between Ir and C atoms (one σ;two π). The lowest quartet state is 4. state which has the configuration:... 1σ2 2σ2 1π4.1δ3 2π1 3σ2 andlies higher than the ground state by 1 .25eV. The molecular constants of the ground state calculatedat CASSCF level by using Morse's mode are: Re=1.6904., De=4.86eV, We=1139cm-1, andB0=0.5219cm-1 comparable with the spectrum values (Re=1 .6858A, De=6.4. eV, We=1051cm-1and B0=0.5251 cm-1).

关键词： Nature of bonding IrC molecular constants CASSCF

The Nature of Bonding in PtN

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Chinese Chemical Letters 1998年第7期9卷 687-690页

作者： Xiao Guang XIE Xian Jun BI Huai CAO Shu Shan DAI (Modem Biological Center, yunnan University, Kunming 650091)(department of chemistry, yunnan {4. University, Kunming 650092)(department of chemistry, yunnan University, Kunming 650091) yunnan Univ Modern Biol Ctr Kunming 650091 Peoples R China yunnan normal Univ Dept Chem Kunming 650092 Peoples R China yunnan Univ Dept Chem Kunming 650091 Peoples R China

The nature of bonding in the title compound has been studed by using CASSCF techniques. The ground state of PtN is found to be (2)Pi state arising primarily from: 1 sigma(2)2 sigma(2)1 pi(4.1 delta(4.3 sigma(2)2 pi(1) configuration, which forms triple bond between Pt and N atoms tone sigma, two pi). The lowest quartet state is (4.Sigma(-) State which has the configuration: ...1 sigma(2)2 sigma(2)1 pi(4.1 delta(4.3 sigma(1)2 pi(2) and lies higher than the ground state by 0.4.eV.

关键词： PtN nature of bonding molcular constants CASSCF

Regioselective aminohalogenation of β-nitrostyrenes using NCS and NBS as nitrogen/halogen sources

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Science china chemistry 2010年第1期53卷 140-146页

作者： ZHI SanJun1,2,SUN Hao2,LIN Chen2,ZHANG GuangQian2,LI GuiGen4.& PAN Yi2,3 1 department of chemistry,Huaiyin normal University,Huai’an 221003,china 2 School of chemistry and Chemical Engineering,Nanjing University,Nanjing 210093,china 3 State Key Lab of Coordination chemistry,Nanjing University,Nanjing 210093,china 4.department of chemistry and Biochemistry,Texas Tech University,Lubbock,Texas 794.9-1061,USA 1. department of chemistry Huaiyin Normal University Huai’an 221003 China2. School of Chemistry and Chemical Engineering Nanjing University Nanjing 210093 China4. Department of Chemistry and Biochemistry Texas Tech University Lubbock Texas 79409-1061 USA3. State Key Lab of Coordination Chemistry Nanjing University Nanjing 210093 China

Aminohalogenation reaction of β-nitrostyrenes with N-halosuccinimides(N-chloro and N-bromosuccinimides) has been successfully conducted by using nickel acetate as a catalyst in the presence of potassium carbonate and succinimide as *** reaction was easily performed at room temperature under nitrogen gas protection to give dihalorinaed haloamino products in good to excellent yields(60%-98%).The structure has been confirmed by X-ray crystal structure analysis.

关键词： aminohalogenation vicinal haloamines β-nitrostyrenes NBS NCS