75-78-5Relevant articles and documents
A General and Selective Synthesis of Methylmonochlorosilanes from Di-, Tri-, and Tetrachlorosilanes
Naganawa, Yuki,Nakajima, Yumiko,Sakamoto, Kei
supporting information, p. 601 - 606 (2021/01/13)
Direct catalytic transformation of chlorosilanes into organosilicon compounds remains challenging due to difficulty in cleaving the strong Si-Cl bond(s). We herein report the palladium-catalyzed cross-coupling reaction of chlorosilanes with organoaluminum reagents. A combination of [Pd(C3H5)Cl]2 and DavePhos ligand catalyzed the selective methylation of various dichlorosilanes 1, trichlorosilanes 5, and tetrachlorosilane 6 to give the corresponding monochlorosilanes.
PROCESS FOR THE STEPWISE SYNTHESIS OF SILAHYDROCARBONS
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Page/Page column 54; 58, (2021/12/08)
The invention relates to a process for the stepwise synthesis of silahydrocarbons bearing up to four different organyl substituents at the silicon atom, wherein the process includes at least one step a) of producing a bifunctional hydridochlorosilane by a redistribution reaction, selective chlorination of hydridosilanes with an ether/HCI reagent, or by selective chlorination of hydridosilanes with SiCI4, at least one step b) of submitting a bifunctional hydridochloromonosilane to a hydrosilylation reaction, at least one step c) of hydrogenation of a chloromonosilane, and a step d) in which a silahydrocarbon compound is obtained in a hydrosilylation reaction.
Method for preparing methylchlorosilanes
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Paragraph 0040-0056, (2020/10/29)
The present invention relates to a method for producing methylchlorosilane by a direct synthesis method and, more specifically, to a method for preparing dimethyldichlorosilane with an improved output of methylchlorosilane (M2) and trimethylchlorosilane (M3). According to the present invention, the method for preparing methylchlorosilane comprises the step of reacting a contact composition including metal silicon, aluminum, a catalyst and a cocatalyst with methyl chloride, wherein the contact composition includes 0.1 to 0.2 parts by weight based on 100 parts by weight of metal silicon.(AA) MCS+ECM+Unreacted MC(BB) ECM+Unreacted MC(CC) FBR(MCS Reactor)(DD) ECM(By-product)(EE) Unreacted MCCOPYRIGHT KIPO 2021
Disilane Cleavage with Selected Alkali and Alkaline Earth Metal Salts
Santowski, Tobias,Sturm, Alexander G.,Lewis, Kenrick M.,Felder, Thorsten,Holthausen, Max C.,Auner, Norbert
supporting information, p. 13202 - 13207 (2019/10/22)
The industry-scale production of methylchloromonosilanes in the Müller–Rochow Direct Process is accompanied by the formation of a residue, the direct process residue (DPR), comprised of disilanes MenSi2Cl6-n (n=1–6). Great research efforts have been devoted to the recycling of these disilanes into monosilanes to allow reintroduction into the siloxane production chain. In this work, disilane cleavage by using alkali and alkaline earth metal salts is reported. The reaction with metal hydrides, in particular lithium hydride (LiH), leads to efficient reduction of chlorine containing disilanes but also induces disproportionation into mono- and oligosilanes. Alkali and alkaline earth chlorides, formed in the course of the reduction, specifically induce disproportionation of highly chlorinated disilanes, whereas highly methylated disilanes (n>3) remain unreacted. Nearly quantitative DPR conversion into monosilanes was achieved by using concentrated HCl/ether solutions in the presence of lithium chloride.
DISILANE-, CARBODISILANE-AND OLIGOSILANE CLEAVAGE WITH CLEAVAGE COMPOUND ACTING AS CATALYST AND HYDROGENATION SOURCE
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Page/Page column 48; 50, (2019/04/16)
The invention relates to a process for the manufacture of monosilanes of formula (I): MexSiHyClz (I), comprising: the step of subjecting a silane substrate (methyldisilanes, methyloligosilanes, or carbodisilanes) to a cleavage reaction of the silicon-silicon bond(s) or the silicon- carbon bonds in silane substrates the reaction involving a cleavage compound selected from a quaternary Group 15 onium compound R4 QX, a heterocyclic amine, a heterocyclic ammonium halide, or a mixture of R3P and RX. The starting material disilanes to be cleaved has the formula (II): MemSi2HnClo (II) The starting material oligosilanes to be cleaved have the general formula (III): MepSiqHrCIs (II I), The starting material carbodisilanes to be cleaved have the general formula (IV): (MeaSiHbCle)-CH2-(MecSiHdClf) (IV)
PROCESS FOR THE PRODUCTION OF ORGANOHYDRIDOCHLOROSILANES FROM HYDRIDOSILANES
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Page/Page column 44; 45, (2019/04/16)
The invention relates to a process for the manufacture of organomonosilanes bearing both hydrogen and chlorine substituents at the silicon atom by subjecting one or more organomonosilanes to the reaction with one or more di- or carbodisilanes in the presence of one or more compounds (C) acting as a redistribution catalyst, wherein at least one of the silanes has only hydrogen and organic residues at the silicon atoms.
Synthesis of Functional Monosilanes by Disilane Cleavage with Phosphonium Chlorides
Santowski, Tobias,Sturm, Alexander G.,Lewis, Kenrick M.,Felder, Thorsten,Holthausen, Max C.,Auner, Norbert
supporting information, p. 3809 - 3815 (2019/02/13)
The Müller–Rochow direct process (DP) for the large-scale production of methylchlorosilanes MenSiCl4?n (n=1–3) generates a disilane residue (MenSi2Cl6?n, n=1–6, DPR) in thousands of tons annually. This report is on methylchlorodisilane cleavage reactions with use of phosphonium chlorides as the cleavage catalysts and reaction partners to preferably obtain bifunctional monosilanes MexSiHyClz (x=2, y=z=1; x,y=1, z=2; x=z=1, y=2). Product formation is controlled by the reaction temperature, the amount of phosphonium chloride employed, the choice of substituents at the phosphorus atom, and optionally by the presence of hydrogen chloride, dissolved in ethers, in the reaction mixture. Replacement of chloro by hydrido substituents at the disilane backbone strongly increases the overall efficiency of disilane cleavage, which allows nearly quantitative silane monomer formation under comparably moderate conditions. This efficient workup of the DPR thus not only increases the economic value of the DP, but also minimizes environmental pollution.
Neutral-Eosin-Y-Photocatalyzed Silane Chlorination Using Dichloromethane
Fan, Xuanzi,Xiao, Pin,Jiao, Zeqing,Yang, Tingting,Dai, Xiaojuan,Xu, Wengang,Tan, Jin Da,Cui, Ganglong,Su, Hongmei,Fang, Weihai,Wu, Jie
supporting information, p. 12580 - 12584 (2019/08/16)
Chlorosilanes are versatile reagents in organic synthesis and material science. A mild pathway is now reported for the quantitative conversion of hydrosilanes to silyl chlorides under visible-light irradiation using neutral eosin Y as a hydrogen-atom-transfer photocatalyst and dichloromethane as a chlorinating agent. Stepwise chlorination of di- and trihydrosilanes was achieved in a highly selective fashion assisted by continuous-flow micro-tubing reactors. The ability to access silyl radicals using photocatalytic Si?H activation promoted by eosin Y offers new perspectives for the synthesis of valuable silicon reagents in a convenient and green manner.
Technique and device for synthesizing methyl chlorosilane
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Paragraph 0014; 0015; 0016, (2017/07/01)
The invention provides a technique and device for synthesizing methyl chlorosilane. The method comprises the following steps: a sand bath temperature control device is started to increase the temperature in a stirred bed reactor to the preset temperature; the weighed silicon powder and catalyst are uniformly mixed and pressed into the stirred bed under the action of nitrogen through a charging device on the upper part of the stirred bed reactor, and a magnetic stirring device is started; methyl chloride in a methyl chloride storage tank is vaporized by a methyl chloride vaporizer and enters the sand bath temperature control device through a fluidized bed inlet flowmeter to control the methyl chloride inlet reaction flow rate; and the reaction product is condensed by the product condenser and collected from the lower part of a product collector, and the uncondensed gas enters a tail gas buffer tank to be collected, is absorbed by an NaOH solution tank and discharged to the outside. The reaction temperature, reaction pressure, methyl chloride quality, silicon powder quality, catalyst quality and other reaction conditions in the methyl chlorosilane production process have favorable evaluation effects, thereby greatly lowering the industrial plant adjustment risks and enhancing the production efficiency.
B(C6F5)3-Catalyzed Selective Chlorination of Hydrosilanes
Chulsky, Karina,Dobrovetsky, Roman
supporting information, p. 4744 - 4748 (2017/04/11)
The chlorination of Si?H bonds often requires stoichiometric amounts of metal salts in conjunction with hazardous reagents, such as tin chlorides, Cl2, and CCl4. The catalytic chlorination of silanes often involves the use of expensive transition-metal catalysts. By a new simple, selective, and highly efficient catalytic metal-free method for the chlorination of Si?H bonds, mono-, di-, and trihydrosilanes were selectively chlorinated in the presence of a catalytic amount of B(C6F5)3 or Et2O?B(C6F5)3 and HCl with the release of H2 as a by-product. The hydrides in di- and trihydrosilanes could be selectively chlorinated by HCl in a stepwise manner when Et2O?B(C6F5)3 was used as the catalyst. A mechanism is proposed for these catalytic chlorination reactions on the basis of competition experiments and density functional theory (DFT) calculations.
