A comparative study on p-doping behavior of polythiophenes with CH<Subscript>3</Subscript>SO<Subscript>3</Subscript>H

Four kinds of polythiophenes have been doped with CH3SO3H in CHCl3 under air, oxygen, and nitrogen. In the doping of two types of poly(3-hexylthiophene)s, P3HexTh(Zn/Ni) and P3HexTh(Fe) with different contents of a head-to-tail unit, the p-doping occurs at a similar rate. The reaction between poly(3-dodecylthiophene), P3DodTh, and the acid takes place more rapidly. P3OBuTh with a butoxy substituent undergoes more facile p-doping and receives photochemical reaction with CHCl3, and this reaction obeys a pseudo-first-order rate law with a rate constant kobs of 1.42×10-5 s-1 at room temperature.     

甲基磺酸铜制备的绿色工艺与动力学

甲基磺酸(ＭＳＡ)及其盐类能改善镀层性能,并可实现无氰电镀[1-4],本文采用空气氧化法直接由紫Ｃｕ与ＭＳＡ水溶液反应生产(ＣＨ3ＳＯ3)2Ｃｕ·5Ｈ2Ｏ,达到了工艺绿色化的要求。1　实验部分1 1　试剂与仪器70%ＭＳＡ(宝鸡科隆化工有限公司);99 9%紫铜片(沈阳冶炼厂);氧气(宝鸡有色金属加工厂氧气分厂);其余试剂均为分析纯试剂。ＡＡ7003Ａ原子吸收光谱仪(北京市东西电子技术研究所);ＰＩＣ-8型离子色谱仪(青岛普仁仪器有限公司);超级恒温槽。1 2　实验将500ｍｌ三口磨口烧瓶装于超级恒温槽中,装温度计、鼓气管,第三只磨口连续接装3支磨…     

Esterification of butyric acid with n-butanol: Kinetic study using experimental data and modeling

Present study involves the investigation of the esterification kinetics between butyric acid and n-butanol. This reaction was conducted in a batch reactor, utilizing homogeneous methanesulfonic acid (MSA) catalyst. Response surface methodology (RSM) was conducted prior to the kinetic study using “Design Expert; version-11.0” for finding the causal factors influencing the conversion of butyric acid. Most important factors identified with their limits against conversions (during optimization of the process using RSM) were taken up to critically analyze the effect of them on butyric acid conversion. Concentration and activity-based model of the process were proposed assuming second order reversible reaction scheme using homogeneous MSA catalyst. During the study of non-ideal behavior of the system, UNIFAC model was adapted for assessing the activity coefficients of species present in equilibrated liquid phase. Experimental data were used to evaluate kinetic and thermodynamic parameters such as rate constants, activation energy, enthalpy, and entropy of the system. The endothermic nature of esterification was confirmed by positive value of enthalpy obtained. The effect of various levels of causal variables like temperature (60–90°C), catalyst concentration (0.5–1.5 wt.%), and molar ratio of n-butanol to butyric acid (1–3) on conversion kinetics of butyric acid was investigated during transient and equilibrium phase of the reaction. It has been observed that molar ratio of butanol to butyric acid has the highest influence on the conversion. The rate equation derived offered a kinetic and thermodynamic framework to the generated data. It also exhibits a notable degree of conformity of predicted data to the experimental ones and effectively characterizes the system across different reaction temperatures, reactant molar ratio, and catalyst concentration.     

A direct route to polythiophenes displaying lateral substituents: Easy one‐step synthesis and polymerization of thiophene monomers substituted by a dimethylenecarboxylate (CH2CH2COOR) appendage on the 3‐position

Thiophene monomers displaying a dimethylenecarboxylate (CH₂CH₂COOR) substituent on the 3‐position of the aromatic ring can be easily obtained and in one step from the electrochemically induced reaction of 3‐bromothiophene with the corresponding acrylate (CH₂?CHCOOR). The synthesis of the ethyl ester monomer, of related 2,5‐dihalogenothiophenes, and their polymerization are reported. Despite the surprisingly low solubilities displayed by the polymers, a full spectroscopic characterization could be performed and the data fully analyzed. Oxidative polymerizations (FeCl₃ or electropolymerization) yield a regioirregular polythiophene, with 60–70% of head‐to‐tail diads. Both experimental and theoretical results suggest that the nonconjugated ester plays a very minor role—if any—in the polymerizations under oxidative conditions, but has a significant influence on the polymer properties. Preliminary attempts to polymerize the dihalogenothiophenes under reductive conditions were hampered by the even lower solubilities exhibited by the regioregular oligomers. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012     

CH3CH2,CH3CHCl,CH3CCl2与NO2反应微观动力学理论研究

运用量子化学密度泛函理论UB3LYP/6-311+G*和高级电子相关校正的偶合簇(CCSD(T)/6-311+G*)方法,对CH3CH2,CH3CHCl和CH3CCl2自由基与NO2反应的机理和动力学进行了理论研究,得到了体系的势能面信息和可能的反应机理.根据计算得到的各反应热力学参数及反应能垒,采用传统过渡态理论计算了各反应在温度T=298 K和T=700 K时的速率常数.研究结果表明,该类反应均通过1个中间体和1个过渡态生成产物,产物分别为CH3CHO+HNO,CH3CHO+ClNO和CH3CClO+ClNO.     

Solvation of complexes with strong symmetric H bonds in the methanesulfonic acid—2-pyrrolidone system

Multiple Attenuated Total Reflectance (MATR) IR spectra of solutions of methanesulfonic acid (MSA) in 2-pyrrolidone (Pyr) (0—100 % MSA) were examined at 30 °C. Depending on the ratio of components, two types of species with strong symmetric H bonds are formed: uncharged quasi-ion pairs of 1 : 1 composition and anions (AHA)^–. The solvation of quasi-ion pairs by base molecules and of the (AHA)^– anions by acid molecules was detected. The data on the influence of the hydrogen bond donor and acceptor on the IR spectra of the quasi-ion pairs and (AHA)^– anions are presented.     

H原子和(CH_3)_2SiH_2抽提反应的理论研究

采用UMP2 / 6- 3 1G(d)理论水平优化了H原子和 (CH3) 2 SiH2 抽提反应势能面上的所有驻点 ,并在此水平基础上进行了内禀反应坐标 (IRC)的计算 ,得到该反应的反应途径 (MEP) .应用变分过渡态理论及最小能量途径半经典绝热基态隧道效应校正 (MEPSAG)、小曲率半经典绝热基态隧道效应校正 (SCSAG)等方法对上述反应进行了动力学研究 ,期望从理论上提供一套温度范围较宽、精度较高的动力学数据 ,为阐明反应机理和解释实验结果提供理论依据     

Ab initio study of the complexes of first-row transition-metal ions with CH, CH_2, and CH_3

The geometries and bonding characteristics of the complexes of the first-row transition-metal ions with CH, CH_2 and CH_3 were investigated by ab initio molecular orbital theory. MCH~ and MCH_2~ are linear and coplanar, re spectively. Both of them are with obvious treble or double bond characteristics, but these multiple bonds are mostly "im perfect". The calculated bond dissociation energies of C--M~ , C=M~ and C≡M~ are mostly close to the experi mental values, and appear in similar periodic trends from Sc to Zn.     

CF3CH2CH3+OH的反应机理及动力学性质的理论研究

采用密度泛函理论BB1K/6-31+G(d,p)计算了反应CF₃CH₂CH₃+OH各反应通道上驻点的稳定结构和振动频率, 并分别在BMC-CCSD, MC-QCISD和G3(MP2)水平上进行了单点能校正. 运用变分过渡态理论, 在BMC-CCSD//BB1K, MC-QCISD//BB1K, G3(MP2)//BB1K以及BB1K水平上计算了各反应通道的速率常数, 讨论了-CH₂和-CH₃基团上H提取通道对总反应的贡献, 并与已有实验和理论结果进行了对比. 计算结果表明, BMC-CCSD水平上的速率常数与实验测量值符合得很好, 进而给出了该水平上反应在200~1000 K温度范围内速率常数k(cm³?molecule^-1?s^-1)的三参数表达式: k=1.90×10^-21T^3.21exp(-292.62/T).     

Heterogeneous reactions of gaseous methanesulfonic acid with NaCl and sea salt particles

Methanesulfonic acid (MSA) has been identified as one of the most important intermediate products of DMS reactions in the atmosphere. Although considerable amounts of MSA have been found in the marine boundary layer, little is known about the interaction of gaseous MSA with sea salt particles. To understand the fate of MSA in the atmosphere and its potential importance in atmospheric chemistry, the heterogeneous reactions of gaseous MSA with micron-scale NaCl and sea salt particles were studied using diffuse reflectance infrared Fourier transform spectrometry, X-ray photoelectron spectroscopy, and scanning electron microscopy. The CH₃SO₃Na and CH₃SO₃ ⁻ were the major products of the condensed phase of the reaction of gaseous MSA with NaCl and with sea salt particles. The steady-state uptake coefficient was determined to be (5.94±2.32)×10⁻⁷ (1 σ) for the reaction of gaseous MSA with NaCl particles and (2.23±1.25)×10⁻⁷ (1 σ) for the reaction of gaseous MSA with sea salt particles. The heterogeneous reaction of MSA with NaCl particles was found to be first-order for MSA. The reaction mechanisms were discussed. Supported by the National Natural Science Foundation of China (Grant No. 40490265) and the National Basic Research Priorities Program (Grant No. 2002CB410802)     

卤代萘与三氧化硫的磺化反应

卤代萘与三氧化硫的磺化反应林静,邹友思（厦门大学化学系,厦门,３６１００５）关键词磺化反应,三氧化硫,卤代萘甲基和甲氧基萘用三氧化硫进行的磺化反应已有报道［１～３］,而卤代萘的磺化反应迄今未见报道．本文研究了６种卤代茶在非极性溶剂二氯甲烷中用三氧化硫...     

1-氟-1,1- 二氯乙烷与氟原子反应的理论研究

利用密度泛函理论研究了CH3CCl2F与F原子的反应机理.在MPW1K水平下计算了反应物、过渡态和产物的几何构型和频率,并进一步利用内禀反应坐标理论获得了反应的最小能量路径;在G3(MP2)水平下对所有驻点进行了单点能量校正.结果表明,CH3CCl2F与F原子的反应存在两个H迁移反应通道:CH2H′CCl 2F+F→C...     

CH_3SH+CN微观反应机理的理论研究

采用BMC-CCSD//B3LYP/6-311G(d,p)方法对CH3SH+CN反应机理进行了详细的理论研究.反应中涉及的各稳定点的构型、振动频率和零点能在B3LYP/6-311G(d,p)水平下计算得到,计算结果表明,该反应存在两种反应机理,5条可能的反应通道.SN2机理由于能垒太高,与直接氢抽提机理相比可以忽略.该反应的最可行通道为CN中的C原子进攻SH中的H原子经由一个前期和一个后期分子络合物生成产物CH3S和HCN.计算得到的反应焓变与已有实验值非常吻合.     

Kinetics of esterification of the levulinic acid with n‐hexanol,n‐octanol,and 2‐ethylhexanol in the presence of methanesulfonic acid as a catalyst under nonisothermal conditions

The levulinic acid was esterified with alcohol at an alcohol to acid molar ratio of 3:1, 5:1, and 10:1 in the presence of a 0.1 wt% methanesulfonic acid catalyst. During esterification, the temperature was changed linearly from 373 to 428 K and its average change was 4.5 K/min. The authors stated that reactions were of second order and that the activation energy (E) decreased from 61 to 46 kJ/mol in the following alcohol sequence: n‐hexanol > n‐octanol > 2‐ethylhexanol. The fitting errors varied between 3.8% and 6.4%. The time of experiment carried out under nonisothermal condition is five to 15 times shorter than that conducted under isothermal conditions. A smaller number of experimental series also determines a significantly lower cost of such research. The results of such study are the precise form of the kinetic equation, which is indispensable in design and optimization of industrial‐scale chemical reactors.     

IR study of ion-molecular interactions in the system methanesulfonic acid-ethyl acetate

The complex formation in the methanesulfonic acid (MSA)—ethyl acetate (EA) system was studied by Multiple Attenuated Total Reflection (MATR) IR spectroscopy at 30°C. In solutions with excess EA, neither protonation of a base nor formation of complexes with a strong symmetrical H bond was observed. Molecular complexes EA·MSA are found in these solutions. Complexes formed by the strong symmetric H bond are observed in the system when the MSA content exceeds 50 mol.% Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2. pp. 292–294, February, 2000.     

CH3COBF4催化四氢呋喃聚合的研究

本文介绍了CH_3COBF_4催化四氢呋喃(THF)的聚合方法,讨论了THF的聚合反应机理和动力学行为。经计算表观活化能为71.68kJ/mol,0℃、6℃和15℃时的表现聚合速度常数分别为1.18、2.35和6.07×10~(-3)L·mol/s;说明反应温度对聚合速度常数有明显的影响.     

Relation between the Structure and Electrochemical Characteristics of Composites Based on 3-Substituted Polythiophenes and Carbon Materials

It was shown that the electrophysical and electrochemical characteristics of composites produced by oxidative polymerization of 3-substituted thiophenes in a dispersion of carbon materials are determined by the degree of ordering in the carbon matrix.     

Synthesis of Poly(3‐hexylthiophene) with a Narrower Polydispersity

Summary: The polymerization of 2‐bromo‐3‐hexyl‐5‐iodothiophene ( 1 ) with isopropylmagnesium chloride and Ni(dppp)Cl₂ was quenched with 5 M hydrochloric acid instead of water to yield head‐to‐tail poly(3‐hexylthiophene) (HT‐P3HT) with a very low polydispersity. The of the polymer was controlled by the feed ratio of 1 to Ni(dppp)Cl₂. Quenching with 5 M hydrochloric acid seemed to promote protonolysis of HT‐P3HT‐Ni complexes before the coupling reaction between HT‐P3HT.

GPC profiles of HT‐P3HT obtained after quenching with water and 5 M hydrochloric acid, respectively.     

Elastic properties and electronic structures of CdCNi3: A comparative study with MgCNi3

We present a first-principles investigation within the density functional theory on the structural, elastic and electronic properties of CdCNi₃ and MgCNi₃. The calculated lattice parameters of CdCNi₃ and MgCNi₃ are in good agreement with the available experimental data. The independent elastic constants are derived from the second derivative of total energy as a function of strain. Furthermore, the elastic modulus and Debye temperatures of CdCNi₃ and MgCNi₃ are predicted. The Ni-3d states play dominant roles near the Fermi levels for both the two compounds, and there is strong hybridization between Ni-3d and C-2p states. Our results also show that CdCNi₃ is quite similar in bonding characteristic to MgCNi₃. The spin-polarized calculations and the fixed spin-moment calculations indicate that both CdCNi₃ and MgCNi₃ have stable non-magnetic state.     

卤代苯和卤代萘用三氧化硫进行的磺化反应

前文报道了各种甲氧基萘用三甲硅基氯磺酸酯在非极性溶剂中进行的磺化反应。本文研究了四种卤代苯和六种卤代萘用三氧化硫在非极性溶剂中进行的磺化反应。卤代芳香化合物用氯磺酸,浓硫酸及发烟硫酸进行的磺化反应已有报道。在芳香化合物的亲电取代反应中,卤素的定位效应取决于以下两个因素。首先,负的诱导效应体现为F>Cl>Br>I,且对邻位的影响远大于对位的影响。而正的共轭效应亦体现为F>Cl>Br>I,对对位的影响最大。单取代卤苯在浓硫酸中进行磺化反应,几乎专一地发生在4—位上。说明尽管卤素降低了芳香环上的电子云密度,但仍为邻对位定位基。三氧化硫(SO_3)是最剧烈的磺化剂,溶于非极性溶剂二氯甲烷中,既减少了付反应,又可在室温下进行高效率的磺化反应。