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DFT Investigation on the Mechanism of Pd(0) Catalyzed sonogashira Coupling reaction

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Chinese Journal of Structural Chemistry 2011年第9期30卷 1289-1297页

作者：陈丽萍陈慧萍 School of Environment & Chemical Engineering Nanchang University Department of Chemistry College of Basic Science East China Jiaotong University

Based on DFT calculations, the catalytic mechanism of palladium（0） atom, commonly considered as the catalytic center for sonogashira cross-coupling reactions, has been analyzed in this study. In the cross-coupling reaction of iodobenzene with phenylacetylene without co-catalysts and bases involved, mechanistically plausible catalytic cycles have been computationally identified. These catalytic cycles typically occur in three stages： 1） oxidative addition of an iodobenzene to the Pd（0） atom, 2） reaction of the product of oxidative addition with phenylacetylene to generate an intermediate with the Csp bound to palladium, and 3） reductive elimination to couple the phenyl group with the phenylethynyl group and to regenerate the Pd（0） atom. The calculations show that the first stage gives rise to a two-coordinate palladium （Ⅱ） intermediate （ArPdI）. Starting from this intermediate, the second oxidative stage, in which the C–H bond of acetylene adds to Pd（Ⅱ） without co-catalyst involved, is called alkynylation instead of transmetalation and proceeds in two steps. Stage 3 of reductive elimination of diphenylacetylene is energetically favorable. The results demonstrate that stage 2 requires the highest activation energy in the whole catalysis cycle and is the most difficult to happen, where co-catalysts help to carry out sonogashira coupling reaction smoothly.

关键词： sonogashira reaction mechanism study DFT calculations palladium atom

sonogashira Coupling reaction with Palladium Powder and Potassium Fluoride in Methanol

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Chinese Journal of Chemistry 2003年第4期21卷 474-476页

作者：王磊李品华 Department of Chemistry Huaibei Coal Teachers College State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

A sonogashira coupling reaction of aromatic halides with terminal alkynes in the presence of palladium powder, potassium fluoride, cuprous iodide and triphenylphosphine in methanol, giving the corresponding coupling p... 详细信息

关键词： sonogashira reaction palladium powder potassium fluoride terminal alkyne aryl alkyne

Copper and amine free sonogashira cross-coupling reaction catalyzed by efficient diphosphane-palladium catalyst

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Chinese Chemical Letters 2011年第10期22卷 1175-1178页

作者： Ting He Lei Lei Wu Xing Li Fu Hai Yan Fu Hua Chen Rui Xiang Li Key lab of Green Chemistry and Technology Ministry of Education College of Chemistry Sichuan University Chengdu 610064 China Guangxi Vocational ＆ Technical Institute of Industry Nanning 530001 China

The commercially available diphosphane ligand MeO-BIPHEP was first investigated in the palladium-catalyzed sonogashira reaction in the absence of copper and *** coupling of various aryl bromides and aryl chlorides wit... 详细信息

关键词： MeO-BIPHEP sonogashira reaction Diphosphane ligand Palladium complex

Synthesis, Structure and Photophysical Properties of Silole-Oxadiazole Copolymers

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Chinese Journal of Chemistry 2013年第6期31卷 779-786页

作者： Tingting Zhang Chaoqiang Zhu Yuwen Ma Chengyun Wang Yongjia Shen Key Laboratory for Advanced Materials and Institute of Fine Chemicals East China University of Science and Technology 130 Meilong Road Shanghai 200237 China

A new conjugated copolymer （PTST-DyOXD） derived from 1,1-dimethyl-3,4-diphenyl-2,5-bis（5-bromo-2- thienyl）-silole （TST） and 2,5-bis（4-ethynylphenyl）-l,3,4-oxadiazole （DyOXD） was synthesized by Pd（0）-catalyzed sonogashira coupling reaction. For comparison, another copolymer without acetenyl group （PTST-OXD） was also synthesized by Pd（0）-catalyzed Suzuki coupling reaction. Chemical structures and optoelectronic properties of the copolymers were characterized by IH NMR, 13C NMR, IR, UV-vis absorption, photoluminescence and cyclic voltammetry. The number-average molecular weight （Mn） is 4010 Da for PTST-DyOXD and 3890 Da for PTST-OXD, respectively. The thermogravimetric analysis （TGA） measurements show that they have good thermal stability with decomposition temperature at 312 and 318 ~C, respectively. The optical band gap is 2.21 eV for PTST-DyOXD and 2.10 eV for PTST-OXD based on the absorption onset. CV analysis revealed the LUMO level of PTST-DyOXD is -3.04 eV, lower than that of PTST-OXD （about -2.89 eV）, which is attributed to the introduction of acetylene group in PTST-DyOXD, increasing the system of the conjugate chain length.

关键词： 2,5-bis(5-bromo-2-thienyl)silole 2,5-bis(4-ethynylphenyl)-1,3,4-oxadiazole sonogashira reaction Suzuki reaction conjugated polymer

Synthesis and properties of a luminescent organic material with triphenylamine and pentiptycene units

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Chinese Chemical Letters 2007年第7期18卷 820-822页

作者： Qing Guo He Xi Peng Guo Jian Gong Cheng Feng Lian Bai Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai 200050 China Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China

A donor-bridge-donor compound for blue light-emitting with triphenylamine as donor and pentiptycene derivative units as bridge was synthesized via sonogashira reaction. The chemical structure was confirmed by NMR and MALDI-TOF MS. It emits blue light peaked at 442 nm with a FWHM of 59 nm in CH2Cl2. Fluorescent quantum efficiency in THF is 82% relative to 9,10-diphenylanthracene. A slight hypsochromic shift was found in its drop-cast film. Cyclic voltammetry revealed that it has high HOMO level corresponding to hole transporting character.

关键词： Triphenamine Pentiptycene sonogashira reaction Blue light Hole transport

One-Pot Synthesis of 1,2,3-Triazoles using Polymer-Supported Propyne in Aqueous Solution

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Chinese Journal of Chemistry 2007年第8期25卷 1202-1206页

作者：商永嘉任连兵王冬梅 College of Chemistry and Materials Science Anhui Normal University Wuhu Anhui 241000 China Anhui Key Laboratory of Functional Molecular Solids Wuhu Anhui 241000 China

A practical and efficient liquid-phase synthesis of 1,2,3-triazoles using poly（ethylene glycol） as support in aqueous solution was described. The title compounds, 1,2,3-triazoles 5 were obtained by a one-pot three-component 1,3-dipolar cycloaddition reaction in middle yields. In addition, a series of unexpected products 7 of sonogashira reaction were also formed under the same condition.

关键词： 1,2,3-triazole poly(ethylene glycol) 1,3-dipolar cycloaddition sonogashira reaction

Synthesis of Conjugated Aryleneethynylenesiloles Dendron

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Chinese Journal of Chemistry 2012年第12期30卷 2861-2868页

作者： Liu Jie Yan Chenxu Li Shanshan Wang Chengyun Shen Yongjia Key Laboratory for Advanced Materials and Institute of Fine Chemicals East China University of Science and Technology Shanghai 200237 China

Three routes were designed to synthesize a n-conjugated aryleneethynylenesiloles dendron. With the desilylation of the disilole mono（silylethynyl） derivative in the presence of potassium carbonate （K2CO3）, the silole-containing oligomer has been successfully synthesized without impact on the Si-（CH3）2 group. The disilole mono- （silylethynyl） derivative was prepared by means of the sonogashira heterocoupling reaction between the diacetylene compound and asymmetrical silole, catalyzed by the dichloro bis（triphenylphosphine）palladium, in a divergent synthesis. Due to their steric effect and triethynylbenzene self-coupling Glaser reaction, the endeavour to prepare the dendron by controlling the molar ratio of asymmetrical silole and 1,3,5-triethynylbenzene was failed. The another attempt to prepare the dendron by different desilylation condition of triisopropylsilyl group and trimethylsilyl group was also failed, the desilylation of Si-（CH3）2 group in silacyclopentadiene unit was also easily accomplished in the presence of tetrabutylammonium fluoride（Bu4NF）, whereas no reaction occurred when K2CO3 was used instead of Bu4NF.

关键词： heterocycles dendrimers silole sonogashira reaction desilylation

Ethynylene-Linked Oligomers Based on Benzodithiophene:Synthesis and Photoelectric Properties

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Chinese Journal of Chemistry 2014年第4期32卷 298-306页

作者： Songyang Jiang Yuwen Ma Yingyi Wang Chengyun Wang Yongjia Shen Key Laboratory for Advanced Materials and Institute of Fine Chemicals East China University of Science and TechnologyShanghai 200237China

Two conjugated ethynyl-linked oligomers,oligo(benzodithiophene-ethynylene-benzothiadiazole)(O1)and oligo(benzodithiophene-ethynylene-carbazole)(O2),were synthesized by sonogashira coupling *** de-grees of polymerization were 7 and 10,*** photophysical and electrochemical properties were in-vestigated.O1 exhibitd two strong absorption bands at 404 nm and 483 nm,and O2 at 401 nm and 429 *** re-sults of UV-Vis,cyclic voltammetry(CV)and theoretical calculations showed that O1 has a narrower band gap than *** conductivities of O1 and O2 were 1.05×10^(−15) and 6.98×10^(−16) S/cm,respectively,and would increase to 1.23×10^(−10) and 1.05×10^(−10) S/cm after doping with iodine.

关键词： benzodithiophene conjugated polymer sonogashira reaction photoelectric property conductivity

Organic–Inorganic Hybrid Material Immobilised TransitionMetals as Highly Efficient and Recyclable Catalysts for Carbon-Carbon Bond Formation

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Organic–Inorganic Hybrid Material Immobilised TransitionMet...