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cyclotrimerization of Aliphatic Aldehydes Catalyzed by Ionic Liquids

Chinese Journal of Chemistry 2006年第8期24卷 1066-1068页

作者：于心玉刘彩华杨建国何鸣元 Shanghai Key Laboratory of Green Chemistry and Chemical Process East China Normal University Shanghai 200062

Aliphatic aldehydes such as ethanal, propanal, n-butanal, isobutyraldehyde, n-valeraldehyde, isovaleraldehyde, n-hexanal and n-octanal were converted into the corresponding 2.4,6-trialkyl-1,3,5-trioxanes through cyclotrimerization in the presence of the ferric chloride based ionic liquids at room temperature without solvent in high selectivity. The effects of different ionic liquids, acidity of ionic liquids and temperature on cyclotrimerization were also studied. The results showed that the ferric chloride based ionic liquids （apparent molar fraction of FeCl3 （x（FeCl3）= 0.62）） were a kind of efficient catalysts for the cyclotrimerization of aliphatic aldehyde which could be separated conveniently from the reaction mixture and recycled without loss of catalytic activity. The conversion of isobutyraldehyde and the selectivity to 2,4,6-triisopropyl-1,3,5-trioxane were 91.1% and 99.8% respectively under optimum reaction condition （isobutyraldehyde 25.0 g, [Et3NH]Cl/FeCl3 （x（FeCl3）=0.62） 1.0 g, 25 ℃ for 1 h）.

关键词： aliphatic aldehyde cyclotrimerization 2,4,6-trialkyl-1,3,5-trioxane ionic liquid

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A Regioselective Method for the Synthesis of Benzene Derivatives:Palladium-Catalyzed cyclotrimerization of Ethyl Propiolate

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Chinese Journal of Chemistry 2003年第3期21卷 361-364页

作者：程金生江焕峰等 LaboratoryofCelluloseandLignocellulosicsChemistry GuangzhouInstituteofChemistryChineseAcademyofSciencesGuangzhouGuangdong510650China StateKeyLaboratoryofOrgnometallicChemistry Sh

An NEt 3 ‐induced palladium complex PdL 2 Cl 2 catalyzed cyclotrimerization reaction of ethyl propiolate (EP) is reported for the first time. The reaction proceeded readily in a regioselective manner under mild conditions to give cyclotrimerization product 1,2,4‐triethyl benzenetricarboxylate as well as its 1,3,5‐isomer in good yields. Influences of the ligands, NEt 3 , solvents, oxidants as well as temperature are studied, and a possible mechanism is also proposed.

关键词： ethyl propiolate palladium complex cyclotrimerization regioselectivity

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Novel Role of Carbon Dioxide as a Selective Agent in Palladium-Catalyzed cyclotrimerization of Alkynes

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Chinese Journal of Chemistry 2004年第12期22卷 1421-1424页

作者：李金恒谢叶香 Key Laboratory of Chemical Biology & Traditional Chinese Medicine Research College of Chemistry and Chemi-cal Engineering Hunan Normal University Changsha Hunan 410081 China

Carbon dioxide was found as a selective agent to promote the palladium-catalyzed cyclotrimerization of alkynes in water. Both aryl and alkylacetylenes afforded the corresponding cyclotrimerization products regioselectively in high yields using PdCl2, CuCl2, and CO2 as the catalytic system. However, tert-butylacetylene bearing a bulky group gave a dimerization product. Mechanism of this reaction was also discussed.

关键词： carbon dioxide a selective agent palladium cyclotrimerization alkyne

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Amine-catalyzed polycyclotrimerization of arylene bipropiolate:A metal-free and regioselective route to hyperbranched polymer

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Science China Chemistry 2008年第8期51卷 705-708页

作者： JIM Cathy K W LAM Jacky W Y HAEUSSLER Matthias Department of Chemistry The Hong Kong University of Science & TechnologyClear Water BayKowloonHong KongChina

This paper presents a new synthetic route to hyperbranched polymer. An arylene bipropiolate monomer,dimethylmethylenebis(1,4-phenylene) bipropiolate,was prepared by a one-step esterification reaction of bisphenol A with propiolic acid. Polycyclotrimrtization of the monomer was effected by reflux in dimethylformamide(DMF),producing a soluble hyperbranched poly(aroxycarbonylphenylene) in a good yield. The polymer was perfectly branched with a degree of branching of 100%.

关键词： cyclotrimerization regioselectivity hyperbranched polymer

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Nickel-Catalyzed Electroreductive Syntheses of Triphenylenes Using ortho-Dihalobenzene-Derived Benzynes

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Chinese Journal of Chemistry 2022年第19期40卷 2335-2344页

作者： Zhao-Ming Li Bin Shuai Cong Ma Ping Fang Tian-Sheng Mei State Key Laboratory of Organometallic Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of Sciences345 Lingling RoadShanghai200032 China

Electrochemical nickel-catalyzed syntheses of triphenylenes by a)reductive trimerization of ortho-dibromobenzenes or ortho-bromoarylsulfurofluoridates,or b)reductive cross-coupling of ortho-dibromobenzenes to 2,2’-diiodobiphenyls,are *** former provides a practical means for the construction of triphenylene derivatives in up to 87%isolated yield at room *** 1,2-dihalo-3-methylbenzenes and related ortho-trisubstituted substrates,trimerizations proceed with high substrate-controlled regioselectivity for the non-C3h symmetric triphenylene isomer.

关键词： Electrochemistry Ni catalysis Benzyne cyclotrimerization Cross coupling

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Surface-Assisted Two-Dimensional Diyne Polycyclotrimerization: Direct Visualization and the Mechanism

Surface-Assisted Two-Dimensional Diyne Polycyclotrimerizatio...

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中国化学会第29届学术年会

作者： Shixuan Du Institute of Physics CAS

cyclotrimerization of alkynes to aromatics represents a promising approach to fabricate two-dimensional conjugated networks due to its single-reactant and atom-economy attributes,in comparison with other multicomponent coupling ***,related reaction mechanism of alkyne cyclotrimerization has not been well understood due to technical *** this work,we take a surface chemical reaction approach to study fundamental polymerization mechanism by using a diyne monomer named 4,4’-diethynyl-1,1’-biphenyl as a test *** have succeeded in directly characterizing reactant,intermediates and its reaction products by using scanning tunneling microscopy,which allows us to gain mechanistic insights into the reaction *** result reveals experimentally for the first time that the polycyclotrimerization is a two-step[2+2+2]cyclization *** work provides an in-depth understanding of polycyclotrimerization process at the atomic level,offering a new avenue to design and construct of single-atom-thick conjugated networks.

关键词： cyclotrimerization diyne surface-assisted reaction first principle calculation STM

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The Synthesis of 2,4,6-Triisopropyl-1, 3,5-trioxane Catalyzed by Ionic Liquids

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Chinese Chemical Letters 2005年第3期16卷 299-302页

作者： JianGuoYANG XinYuYU HaiHongWU ZhiLinCHENG YueMingLIU MingYuanHE ShanghaiKeyLaboratoryofGreenChemistryandChemicalProcesses EastChinaNormalUniversityShanghai200062

The synthesis of 2, 4, 6-triisopropyl-1, 3, 5-trioxane with high yield and desirable selectivity from solvent-free cyclotrimerization of isobutyraldehyde catalyzed by ionic liquids was reported in this work.

关键词： Isobutyraldehyde cyclotrimerization 2 4 6-triisopropyl-1 3 5-trioxane ionic liquids.

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Key Growth Mechanism of Metal Clusters on a Graphene/Ru(0001) Template

Key Growth Mechanism of Metal Clusters on a Graphene/Ru(0001...

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中国真空学会2014学术年会

作者： Lizhi Zhang Yanfang Zhang Shixuan Du Hongjun Gao

Using first-principles calculations combined with scanning tunneling microscopy experiments,we investigated the adsorption configurations,electronic structures and the corresponding growth mechanism of several transition metal(TM)atoms(Pt,Ru,Ir,Ti,Pd,Au,Ag,and Cu)on a graphene/Ru(0001)moire template(G/Ru(0001))at low *** find that Pt,Ru,Ir,and Ti selectively adsorb on the fcc region of G/Ru(0001)and form ordered dispersed metal *** behavior is due to the unoccupied d orbital of the TM atoms and the strong sp hybridization of carbon atoms in the fcc region of G/Ru(0001).Pd,Au,Ag,and Cu form nonselective structures because of the fully occupied d *** mechanism can be extended to metals on a graphene/Rh(111)*** using Pt as an example,we provide a layer by layer growth path for Ptnanoclusters in the fcc region of the G/Ru(0001).The simulations of growth mechanism agree well with the experimental ***,they also provide guidance for the selection of suitable metal atoms toform ordered dispersed metal nanoclusters on similar templates.

关键词： cyclotrimerization diyne surfaceassisted reaction first principle calculation STM

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异氰酸根环三聚制备高性能高分子材料

异氰酸根环三聚制备高性能高分子材料

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2014年全国高分子材料科学与工程研讨会

作者：朱士洋张先明陈文兴冯连芳浙江理工大学先进纺织材料与制备技术教育部重点实验室浙江大学化学工程国家重点实验室化学工程与生物工程学系

聚合物材料的热膨胀系数较大,提高其耐热性成为开发高性能高分子材料的一个重要目标。对异氰酸根基聚合物热稳定的提高主要通过引入耐热性高的杂化基团来生成含有尿烷,恶唑烷酮和异氰脲酸酯结构的复合物,其中异氰脲酸酯基聚合物的耐热... 详细信息

聚合物材料的热膨胀系数较大,提高其耐热性成为开发高性能高分子材料的一个重要目标。对异氰酸根基聚合物热稳定的提高主要通过引入耐热性高的杂化基团来生成含有尿烷,恶唑烷酮和异氰脲酸酯结构的复合物,其中异氰脲酸酯基聚合物的耐热性最好

关键词： Isocyanates cyclotrimerization isocyanurate

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