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Heterogeneously supported pseudo-single atom Pt as sustainable hydrosilylation catalyst

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Nano Research 2018年第5期11卷 2544-2552页

作者： Huachao Zai Yizhou Zhao Shanyu Chen Lei Ge Changfeng Chen Qi Chen Yujing Li State Key Laboratory of Heavy Oil Department of Materials Science and Engineering College of Science China University of Petroleum Beijing 102249 China Beijing Key Laboratory of Construction Tailorable Advanced Functional Materials and Green Applications School of Materials Science and Engineering Beijing Institute of Technology Beijing 100081 China

The identification of highly active heterogeneous catalysts to replace their homogeneous counterparts remains a challenge in the case of organic catalysts, especially polymers, in highly viscous reaction systems. In this work, we designed and synthesized a novel, solid-supported, and heterogeneous pseudo-single atom Pt catalyst with high activity and recyclability. Superparamagnetic Fe3O4-SiO2 core--shell nanoparticles （NPs） were used as the substrate. The functionalization of the SiO2 shell with silane coupling agents containing vinyl groups allows stabilizing Pt on the SiO2 surface through complexation. The as-prepared pseudosingle atom Pt displays high activity in the hydrosilylation of allyl-terminated polyether with polymethylhydrosiloxane and could be easily collected by applying a magnetic field. The Pt/vinyl/SiO2/Fe3O4 catalyst can be reused for up to four reaction cycles without appreciable decrease in activity. This work demonstrates a novel strategy for the design of pseudo-single atom noble metal catalysts for processes in high-viscosity media.

关键词： hydrosilylation superparamagnetic core-shell catalyst single-atom catalyst recyclable catalyst

Well-defined coordination environment breaks the bottleneck of organic synthesis:Single-atom palladium catalyzed hydrosilylation of internal alkynes

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Nano Research 2022年第2期15卷 1500-1508页

作者： Shicheng Ren Bochao Ye Siying Li Liping Pang Yingming Pan Haitao Tang State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources School of Chemistry and Pharmaceutical SciencesGuangxi Normal UniversityGuilin 541004China

Single-atom site(SAS)catalysts have attracted considerable attention due to their excellent ***,most of the current research models of SAS catalysts are based on inorganic catalysts,where“metal and coordination atom interaction”cannot simulate the fine-tuning effect of organic ligands on metal catalytic centers in homogeneous ***,certain chemical transformations in homogeneous catalysis cannot be perfectly ***,we used porous organic ligand polymers as the carrier,which effectively changes the charge regulation of nanoparticles and monoatomic metal *** lessons from traditional homogeneous metal/ligand catalysis,we introduced various functional groups into the ligand polymers to adjust the electronic properties,and successfully realized the hydrosilylation of internal alkynes with high catalytic *** selectivity and catalytic efficiency under the Pd@POL-1 catalyst system were improved compared with previous *** internal alkynes with various structures can complete this reaction,and the ratio of E/Zcan reach up to 100:1.

关键词： single-atom site catalysts porous organic ligand polymers palladium catalysis hydrosilylation internal alkynes

Palladium-catalyzed hydrosilylation of ynones to access siliconstereogenic silylenones by stereospecific aromatic interactionassisted Si–H activation

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Science China Chemistry 2021年第5期64卷 761-769页

作者： Jia-Le Xie Zheng Xu Han-Qi Zhou Yi-Xue Nie Jian Cao Guan-Wu Yin Jean-Philippe Bouillon Li-Wen Xu Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education Key Laboratory of Organosilicon Material Technology of Zhejiang ProvinceHangzhou Normal UniversityHangzhou 311121China State Key Laboratory for Oxo Synthesis and Selective Oxidation Suzhou Research Institute(SRI)Lanzhou Institute of Chemical Physics(LICP)University of the Chinese Academy of Sciences(UCAS)Lanzhou 730000China Normandie University INSA RouenUNIROUENCNRSCOBRA(UMR 6014)Rouen 76000France

hydrosilylation is one of the most important reactions in synthetic chemistry and ranks as a fundamental method to access organosilicon compounds in industrial and academic ***,the enantioselective construction of chiral-at-silicon compounds via catalytic asymmetric hydrosilylation remained limited and *** we report a highly enantioselective hydrosilylation of ynones,a type of carbonyl-activated alkynes,using a palladium catalyst with a chiral binaphthyl phosphoramidite *** stereospecific hydrosilylation of ynones affords a series of silicon-stereogenic silylenones with up to 94%yield,>20:1 regioselectivity and 98:2 *** density functional theory(DFT)calculations were conducted to elucidate the reaction mechanism and origin of high degree of stereoselectivity,in which the powerful potential of aromatic interaction in this reaction is highlighted by the multiple C–H-πinteraction and aromatic cavity-oriented enantioselectivitydetermining step during desymmetric functionalization of Si–H bond.

关键词： asymmetric catalysis DFT calculations hydrosilylation silicon-stereogenic vinylsilanes aromatic interaction

Trace amount of single-atom palladium-catalyzed selective hydrosilylation of allenes

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Nano Research 2022年第8期15卷 7091-7098页

作者： Li-Ping Pang Xin-Yu Li Shi-Cheng Ren Hong-Min Lin Ying-Chun Wang Ying-Ming Pan Hai-Tao Tang State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources School of Chemistry and Pharmaceutical Sciences of Guangxi Normal UniversityGuilin 541004China College of Chemistry and Chemical Engineering Jishou UniversityJishou 416000China

Using fewer catalysts to promote the chemical conversion of more substrates is the dream synthesis pursued by synthetic *** highly selective reactions using trace amounts(100:1).The catalyst could be recycled numerous... 详细信息

Using fewer catalysts to promote the chemical conversion of more substrates is the dream synthesis pursued by synthetic *** highly selective reactions using trace amounts(hydrosilylation of allenes(Pd loading was as low as 0.98 ppm).The synergistic effect of the dispersed catalytic active sites in the catalyst and supports with ligand regulation function can directionally realize the formation of specifically configured hydrosilylation *** as-fabricated single-atom catalyst(SAC;i.e.,Pd1@POL-5)showed an amazing catalytic efficiency and selectivity for hydrosilylation of allene(turnover number was up to 772,358,which was 200 times higher than previously recorded,and regioselectivity>100:1).The catalyst could be recycled numerous times in a continuous flow system without reductions in activity and *** work demonstrated the application prospect of the SAC in the synthesis of complex organic compounds and trace amount catalysis,which can lay the foundation for its large-scale and industrialized application in drug synthesis and other fields.

关键词： trace catalysis single-atom catalysts hydrosilylation allenes

SYNTHESIS OF POLYSILOXANE-SUPPORTED SELENAETHER PLATINUM COMPLEX AND ITS CATALYTIC PROPERTY FOR hydrosilylation OF OLEFINS

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Chinese Journal of Polymer Science 1996年第4期14卷 289-294页

作者：卢雪然陈臻段和平陈亦凡 Department of Chemistry Wuhan University Wuhan 430072 The Center of Analysis and Measurement Chinese Geology University Wuhan 430074

A new type of selenious polymer, silica-bound polybispropoxyethyl-selenidesilsesquinoxane, and its platinum complex were synthesized from bis-allyloxyethyl selenide via hydrosilylation with triethoxysilane, followed by immobilized on fumed silica, and then reacting with potassium chloroplatinite under nitrogen atmosphere in acetone. It was found that the platinum complex can catalyze the hydrosilylation of olefins with triethoxysilane effectively. The effects of the nature of the substrate, the amount of complex used, and the reaction temperature on the catalytic activity were investigated.

关键词： selenaether platinum hydrosilylation catalyst hydrosilylation polysiloxane

Rare-earth metal catalysts for alkene hydrosilylation

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Science China Chemistry 2019年第5期62卷 571-582页

作者： Deshuai Liu Boyu Liu Zexiong Pan Jianfeng Li Chunming Cui State Key Laboratory of Elemento-organic Chemistry and College of Chemistry Nankai University Collaborative Innovation Center of Chemical Science and Engineering (Tianjin)

Rare-earth metal catalyzed hydrosilylation of alkenes has emerged as a powerful and selective strategy for the synthesis of organosilanes. This transformation can offer distinctive catalytic sequences and reaction patterns from other catalysts because of the high electropositivity and lack of oxidative-addition process of rare-earth metal. This review summarizes the rare-earth metal catalysts for hydrosilylation of alkene according to the type of ligands. The synthesis and structure of rare-earth metal catalysts,the substrate scope as well as some preliminary structure-activity relationship and mechanism are discussed.

关键词： rare-earth metal hydrosilylation alkene catalysis mechanism

MCM-41-Supported Bidentate Phosphine Rhodium Complex： An Efficient and Recyclable Heterogeneous Catalyst for the hydrosilylation of Olefins

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Chinese Journal of Chemistry 2011年第8期29卷 1629-1634页

作者：胡荣华郝文燕蔡明中 Department of Chemistry Jiangxi Normal University Nanchang Jiangxi 330022 China Department of Chemistry Jinggangshan University Jian Jiangxi 343009 China

MCM-41-supported bidentate phosphine rhodium complex （MCM-41-2P-RhC13） was conveniently synthesized from commercially available and cheap γ-aminopropyltriethoxysilane via immobilization on MCM-41, followed by reacting with diphenylphosphinomethanol and rhodium chloride. It was found that the title complex is a highly efficient catalyst for the hydrosilylation of olefins with triethoxysilane and can be recovered and recycled by a simple filtration of the reaction solution and used for at least 10 consecutive trials without any decreases in activity.

关键词： supported catalyst hydrosilylation diphosphino-functionalized MCM-41 rhodium heterogeneous catalysis

THE hydrosilylation REACTION OF LADDERLIKE POLYVINYLSILSESQUIOXANE WITH 1, 1, 3, 3-TETRAMETHYLDISILOXANE

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Chinese Journal of Polymer Science 1998年第3期16卷 226-233页

作者：曹新宇许辉王乐天李泽曹明谢萍张榕本朱传凤王琛 PCLCC Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China Polymer Chemistry Laboratory Chinese Academy of Sciences and China Petro-Chemical Corporation Youth Laboratory of Nanoscience and Technology Chinese Academy of Sciences Beijing 100080 China

The hydrosilylation reaction of ladderlike polyvinylsilsesquioxane (Vi-T) with 1, 1, 3, 3-tetramethyldisiloxane (H-MM) catalyzed by dicyclopentadienyl-dichloroplatinium (Cp2PtCl2) was carried out well in tetrahydrofuran (THF) to produce a soluble white solid. This product was characterized by IR, H-1-NMR, C-13-NMR, Si-29-NMR, DSC, X-ray diffraction method, gel permeation chromatography (GPC), vapour pressure osmometry (VPO), atomic force microscopy (AFM) and molecular simulation. These results prove that the product contains nanoscale tubular structure.

关键词： hydrosilylation polyorganosiloxane tubular structure characterisation

Heterometallic Mg-Ni-Mg Complex Promoted hydrosilylation of Alkenes: Catalytic Performance and Intermediates Characterization

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Chinese Journal of Chemistry 2024年第18期42卷 2133-2139页

作者： Yanping Cai Shengjie Jiang Xin Xu Key Laboratory of Organic Synthesis of Jiangsu Province College of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhouJiangsu 215123China

Background and Originality Content The catalytic hydrosilylation of unsaturated hydrocarbons,facilitated by transition metal(TM),is widely recognized as a proficient technique for the synthesis of high-value organosilicon compounds'ti-4l over the past few decades,the most dominant *** in hydrosilylation processes have been constituted by pre-Ccious metar complexesroceinerecent vears omore sustainabile earth-abundant metal catalysts have received increased attentionj2-14l The classcal mechanism of transition metal-catalyzed hydrosilylation is generally accomplished through a series of fundamental processes(Scheme 1a),including(i)coordination and oxidative addition of Si-H bond to a low-valent metal center to form e.g.,o-complex or silyl metal hydride;(ii)insertion of.C-C multipe bonds intometal-hdridelsior metal-silicon bond;jiol and(ii)reductive elimination that forwards the hydrosilylated product with Markovnikov or anti-Markovnikov selectivity.

关键词： Heterometallic complex Cooperative effect hydrosilylation Magnesium Nickel hydride