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Predicting Rate Constants for nucleophilic reactions of Amines with Diarylcarbenium Ions Using an ONIOM Method

Chinese Journal of Chemical Physics 2010年第6期23卷 669-674,745页

作者：张志平王晨傅尧郭庆祥中国科学技术大学化学系合肥230026

The rate constants of the nucleophilic reactions between amines and benzhydrylium ions were calculated using first-principles theoretical methods. Solvation models including PCM, CPCM, and COSMORS, as well as different types of atomic radii including UA0, UAKS, UAHF, Bondi, and UFF, and several single-point energy calculation methods （B3LYP, B3P86, B3PW91, BHANDH, PBEPBE, BMK, M06, MP2, and ONIOM method） were examined. By comparing the correlation between experimental rate constants and the calculated values, the ONIOM（CCSD（T）/6-311＋＋G（2df,2p）：B3LYP/6-311＋＋G（2df,2p））//B3LYP/6- 31G（d）/PCM/UFF） method was found to perform the best. This method was then employed to calculate the rate constants of the reactions between diverse amines and diarylcarbenium ions. The calculated rate constants for 65 reactions of amines with diarylcarbenium ions are in agreement with the experimental values, indicating that it is feasible to predict the rate constant of a reaction between an amine and a diarylcarbenium ion through ab initio calculation.

关键词： Amine Diarylcarbenium ion nucleophilic reaction Rate constant N-layered integrated molecule orbit and molecule mechanics

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nucleophilic substitution of hydrogen in naphthalene by chloride(Cl^-)in ionic liquids

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Chinese Chemical Letters 2011年第2期22卷 147-150页

作者： Shen Yi Shi Ai Guo Kong Xin Hua Zhao Han Ming Ding Fan Yang Yong Kui Shan Department of Chemistry East China Normal UniversityShanghai 200062China

nucleophilic aromatic substitution of hydrogen in non-activated aromatic ring,a very rare phenomenon in organic chemistry,is found in ionic liquids containing Cl^- as anion under mild reaction *** reaction may be carried out by the addition of the halogen-bonding adduct（Br2Cl^-） as nucleophile to aromatic ring carbon atom,leading to the formation of the nucleophilic substitution product.

关键词： Ionic liquid Aromatic compound Naphthalene nucleophilic reaction Halogen bonding

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A high-loading and cycle-stable solid-phase conversion sulfur cathode using edible fungus slag-derived microporous carbon as sulfur host

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Nano Research 2023年第6期16卷 8360-8367页

作者： Hui Li Xiangjiang Wu Sijie Jiang Qian Zhang Yuliang Cao Hanxi Yang Feifei Cao Xinping Ai Hubei Key Laboratory of Electrochemical Power Sources College of Chemistry&Molecular ScienceWuhan UniversityWuhan 430072China College of Science Huazhong Agricultural UniversityWuhan 430070China

Developing a high sulfur(S)-loading cathode with high capacity utilization and long term cyclability is a key challenge for commercial implementation of Li-S battery *** overcome this challenge,we propose a solid-phase conversion sulfur cathode by using an edible fungus slag-derived porous carbon(CFS)as sulfur host to fabricate the S/CFS composite and meanwhile,utilizing the vinyl carbonate(VC)as co-solvent of the ether-based electrolyte to in-situ form a protective layer on the S/CFS composite surface through its nucleophilic reaction with the freshly generated lithium polysulfides(LiPSs)at the very beginning of initial discharge,thus isolating the interior sulfur from the outer electrolyte and inhibiting the further generation of soluble *** from the ultrahigh specific surface area of>3,000 m^(2)·g^(−1),ideal pore size of2.0 cm^(3)·g^(−1)of the CFS host matrix,the S/CFS cathode even with a high S-loading of 80 wt.%(based on the weight of S/CFS composite)can still operate in a solid-phase conversion manner in the VC-ether co-solvent electrolyte to exhibit a high reversible capacity of 1,557 mAh·g^(−1),a high rate capability with 50%remaining capacity at 2 A·g^(−1)and a high cycling efficiency of 99.9%over 500 *** results presented in this work suggest that a combined action of solid-phase conversion electrochemistry and nanoarchitectured host structure may provide a new path for the design and development of practical lithium-sulfur batteries.

关键词： lithium-sulfur batteries solid-phase conversion high sulfur loading cathode edible fungus slag-derived carbon nucleophilic reaction

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reactions of enamines with fluorinated acyl chlorides----Synthesis of fluorinated 1,3-diketones and 1,3-keto-aldehydes

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Chinese Journal of Chemistry 1998年第6期16卷 549-556页

作者：贺海鹰曲延玲赵成学 College of Chemistry and Chemical Technology Shanghai Jiaotong University800 Dongchuan LuShanghai 200240China

The reactions of enamines (1a–b, 4, 6) with fluorinated acyl chlorides (2a–d ) produced fluorinated 1,3-diketones (3a–f) and 1,3-keto-aldehydes (7a–c) in good yields as well as byproducts fluorinated acylamides (5a–c). It is proposed that the reactions involve nucleophilic attack by the C-atom and/or N-atom of the enamines on acyl carbon of the fluorinated acyl chlorides.

关键词： Fluorinated 1,3-dicarbonyl compounds Enamine fluorinated acyl chloride nucleophilic reaction

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Synthesis and Characterization of Multithiouracils

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有机化学 2003年第Z1期23卷 236-236页

作者： WANG Wei LIU Hui-Min ZHANG Wei ZHANG Wen-Qin Department of Chemistry Tianjin University Tianjin 300072 Department of Chemistry Tianjin University Tianjin 300072 Department of Chemistry Tianjin University Tianjin 300072 Department of Chemistry Tianjin University Tianjin 300072

　　Alkylation of bases group of nucleic acid, thymine and uracil, has attracted great attention. In order to investigate the intermolecular interactions, [1,2] and the photoreactions[3,4] between bases group of nucleic acid, many studies were focused on the synthesis of bisbases in the formation of B-(CH2)n-B (B′) in which trimethylene was commonly used as linker. Thiouracil is an important derivative of nucleic acid bases, and it can interfere with the synthesis of thyroxine, especially in the treatment of hyperthyroidism and angina. However, to our knowledge, the synthesis of bisthiouracils, even trithiouracils, using flexible or rigid linkers has not been reported. Herein, we have synthesized eight thiouracil derivatives by nucleophilic reaction between thiouracil and varied bromides. All the compounds have been characterized by IR, 1H NMR and element analysis.……

关键词： nucleic acid intermolecular interactions nucleophilic reaction element analysis

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