2602-34-8Relevant articles and documents
Preparation method of epoxy silane coupling agent
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Paragraph 0078-0079, (2021/05/05)
The invention provides a preparation method of an epoxy silane coupling agent. The preparation method comprises the following steps: (1) synthesizing diallyl ether from chloropropene and allyl alcohol under the action of a catalyst and an alkali; (2) carrying out a hydrosilylation reaction on the diallyl ether and hydrogen-containing chlorosilane under the action of a platinum catalyst to obtain allyloxopropyl chlorosilane; (3) carrying out esterification reaction on the allyloxopropyl chlorosilane and saturated alcohol to obtain allyloxoalkoxy silane; and (4) carrying out epoxidation on the allyloxyalkoxy silane by using an oxidizing agent, so as to obtain gamma-(2, 3-epoxypropoxypropyl)alkoxy silane. The preparation method provided by the invention can be suitable for all gamma-(2, 3-epoxypropoxypropyl) epoxy silane, the used catalyst and raw materials are easy to obtain, the yield is high, and the industrial feasibility is high.
Platinum-Imidazolyl Schiff Base Complexes Immobilized in Periodic Mesoporous Organosilica Frameworks as Catalysts for Hydrosilylation
Huo, Yingpeng,Hu, Jiwen,Tu, Yuanyuan,Huang, Zhenzhu,Lin, Shudong,Hu, Yangfei,Feng, Chao
, (2020/05/18)
An imidazolyl Schiff base-containing periodic mesoporous organosilica (PMO) was synthesized via co-condensation reactions between a newly prepared bis (imidazolyl)imine-bridged bis silane and tetraethyl orthosilicate in the presence of cetyltrimethyl ammonium bromide as a soft template. The resultant as-synthesized PMO was then employed as a solid support for platinum catalysts. This complex was fully characterized via various techniques including FTIR, solid-state13C NMR, and 29Si-NMR spectroscopy, as well as N2 adsorption/desorption analysis, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) methods. In addition, the catalyst was proven to efficiently mediate hydrosilylation reactions between olefins and hydrosilanes, and it can be reused for at least five cycles without significant loss of activity.
Platinum(II) complexes bearing bulky Schiff base ligands anchored onto mesoporous SBA-15 supports as efficient catalysts for hydrosilylation
Huo, Yingpeng,Hu, Jiwen,Lin, Shudong,Ju, Xingming,Wei, Yanlong,Huang, Zhenzhu,Hu, Yangfei,Tu, Yuanyuan
, (2019/04/26)
Reported herein is an easy-to-prepare novel heterogeneous catalyst of platinum complexes bearing binary ligands of bidentate naphthalenolimine and cyclo-1,5-octadiene that are anchored onto mesoporous silica SBA-15. The presence of the binary ligands not only stabilized the platinum, but also enabled the platinum atoms to form nanoclusters with diameters of ca 1?nm, and led to high platinum loading (8.69?wt%). Moreover, the platinum catalyst exhibited high catalytic activity towards hydrosilylation of terminal alkenes and styrene with silanes under mild and solvent-free conditions, with excellent regioselectivity.
Highly-active, graphene-supported platinum catalyst for the solventless hydrosilylation of olefins
Kong, Caleb J.,Gilliland, Stanley E.,Clark, Brian R.,Gupton, B. Frank
supporting information, p. 13343 - 13346 (2018/12/13)
Herein we report the development of the first graphene-supported platinum catalyst that has demonstrated exceptional catalytic activity and stability for hydrosilylation reactions of olefins (TOF 4.8 × 106 h-1, TON = 9.4 × 106). The catalyst also exhibited functional group tolerance over a broad range of industrially relevant substrates with minimal metal leaching. In addition, the catalyst system was successfully translated into a packed bed platform for continuous hydrosilylation reactions.
Nano-dispersed platinum(0) in organically modified silicate matrices as sustainable catalysts for a regioselective hydrosilylation of alkenes and alkynes
Duke, Brett J.,Akeroyd, Evan N.,Bhatt, Shreeja V.,Onyeagusi, Chibueze I.,Bhatt, Shreya V.,Adolph, Brandy R.,Fotie, Jean
, p. 11782 - 11795 (2018/07/25)
Nano-dispersed platinum(0) particles stabilized in a range of organically modified silicate (ORMOSIL) matrices are investigated as sustainable catalysts for the hydrosilylation of alkenes and alkynes. In this study, five different siloxane matrices including triethoxysilane (HTEOS), methyltriethoxysilane (MTES), ethyltriethoxysilane (ETES), triethoxyvinylsilane (TEVS) and propyltriethoxysilane (PTES) are investigated, and the distribution of the metal particles in these materials analyzed by transition electron microscopy (TEM). The particles appeared to be generally of a small size, with a diameter of ca. 2-5 nm in each of these catalysts, however the distribution is not equally uniform from one matrix to the other. HTEOS, MTES and ETES that respectively carry a hydrogen, a methyl and an ethyl group on the triethoxysilane moiety, displayed a more uniform distribution, while particles appeared to be more scattered in the remaining matrices. Catalysts with a uniform particles distribution produced higher and consistent yields, while those with poor particles distribution produced lower and almost random yields, suggesting that the uniformity in particle distribution, and by extension the nature of the siloxane matrix, are important for the catalytic properties of these materials. The scope of the reaction was broadened to a range of olefins, with a goal of investigating the tolerability of the reaction toward a number of reactive functional groups, resulting in the preparation of 28 compounds. This catalytic system also enabled the hydrosilylation of a limited number of alkynes under the optimized reaction conditions.
Discovering Partially Charged Single-Atom Pt for Enhanced Anti-Markovnikov Alkene Hydrosilylation
Chen, Yuanjun,Ji, Shufang,Sun, Wenming,Chen, Wenxing,Dong, Juncai,Wen, Junfeng,Zhang, Jian,Li, Zhi,Zheng, Lirong,Chen, Chen,Peng, Qing,Wang, Dingsheng,Li, Yadong
supporting information, p. 7407 - 7410 (2018/06/11)
The hydrosilylation reaction is one of the largest-scale application of homogeneous catalysis and is widely used to enable the commercial manufacture of silicon products. However, considerable issues including disposable platinum consumption, undesired side reactions and unacceptable catalyst residues still remain. Here, we synthesize a heterogeneous partially charged single-atom platinum supported on anatase TiO2 (Pt1δ+/TiO2) catalyst via an electrostatic-induction ion exchange and two-dimensional confinement strategy, which can catalyze hydrosilylation reaction with almost complete conversion and produce exclusive adduct. Density functional theory calculations reveal that unexpected property of Pt1δ+/TiO2 originates from atomic dispersion of active species and unique partially positive charge Ptδ+ electronic structure that conventional nanocatalysts do not possess. The fabrication of single-atom Pt1δ+/TiO2 catalyst accomplishes a reasonable use of Pt through recycling and maximum atom-utilized efficiency, indicating the potential to achieve a green hydrosilylation industry.
DEHYDROGENATIVE SILYLATION, HYDROSILYLATION AND CROSSLINKING USING PYRIDINEDIIMINE COBALT CARBOXYLATE CATALYSTS
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Page/Page column 42; 43, (2017/02/24)
A process for producing a silylated product comprises reacting a mixture comprising (a) an unsaturated compound containing at least one unsaturated functional group, (b) a silyl hydride containing at least one silylhydride functional group, and (c) a catalyst, optionally in the presence of a solvent, to produce a dehydrogenative silylated product, a hydrosilylated product, or a combination of a dehydrogenative silylated product and a hydrosilylated product, wherein the catalyst is chosen from a pyridine diimine cobalt dicarboxylate complex or a cobalt carboxylate compound, and the process is conducted without pre-activating the catalyst via a reducing agent and/or without an initiator or promoter compound. The present catalysts have been found to be active in the presence of the silyl hydride employed in the silylation reaction.
Process for manufacturing polysiloxane microcapsules that are functionalized and are not very porous
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Page/Page column 4, (2016/09/26)
A method is provided for encapsulating products that can have lipophilic or hydrophilic, including volatile, properties in a polysiloxane membrane that is particularly impervious. A method is also provided for evaluating the imperviousness of capsules. The present method includes the following steps: a) formation of droplets by an emulsion between an oily phase containing the product to be encapsulated and an acidic aqueous phase heated to around 50° C. and in the presence of surfactants; b) addition and hydrolysis of at least one silane in order to obtain a silanol; c) increasing the pH in order to start condensation of the silanol to form a first membrane around the droplets of the product to be encapsulated; d) lowering the pH; e) increasing the pH, optionally preceded by adding a silane, in order to obtain a new condensation of silanol around the droplets of the product to be encapsulated.
Synthesis of a fumed silica-supported poly-3-(2-aminoethylamino)propylsiloxane platinum complex and its catalytic behavior in the hydrosilylation of olefins with triethoxysilane
Li, Ji,Zhang, Lei,Li, Tingting,Yang, Chunhui
, p. 728 - 733 (2016/05/09)
A novel fumed silica-supported bidentate nitrogen platinum complex was conveniently prepared from N-(2-aminoethyl)-3-aminopropyltriethoxysilane via immobilization on fumed silica followed by a reaction with hexachloroplatinic acid. The title complex was systematically characterized and analyzed by Fourier Transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and specific surface area analysis (BET). The resulting title complex was found to be efficient and stable in catalyzing the hydrosilylation reaction of olefins with triethoxysilane. Furthermore, the polymeric platinum complex could be separated by simple filtration and reused four times without any appreciable loss of catalytic activity.
Bench-Stable, Substrate-Activated Cobalt Carboxylate Pre-Catalysts for Alkene Hydrosilylation with Tertiary Silanes
Schuster, Christopher H.,Diao, Tianning,Pappas, Iraklis,Chirik, Paul J.
, p. 2632 - 2636 (2016/04/26)
High-spin pyridine diimine cobalt(II) bis(carboxylate) complexes have been synthesized and exhibit high activity for the hydrosilylation of a range of commercially relevant alkenes and tertiary silanes. Previously observed dehydrogenative silylation is suppressed with the use of sterically unencumbered ligands, affording exclusive hydrosilylation with up to 4000 TON. The cobalt precatalysts were readily prepared and handled on the benchtop and underwent substrate activation, obviating the need for external reductants. The cobalt catalysts are tolerant of epoxide, amino, carbonyl, and alkyl halide functional groups, broadening the scope of alkene hydrosilylation with earth-abundant metal catalysts.
