- Trimethylsilyl Derivatives for the Study of Silicate Structures. Part 7. Calcium Silicate Structures
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A detailed study was made of the yield and products of trimethylsilylation of calcium orthosilicate (Ca2), rankinite (Ca3), and pseudowollastonite (Ca3) under various experimantal conditions.With hexamethyldisiloxane, chlorotrimethylsilane, and isopropylalcohol as reagents, in the absence of added water Ca2 yielded predominantly SiO4(SiMe3)x(Pri)4-x (x = 1-4) and a lesser amount of Si2O7(SiMe3)x(Pri)6-x (x = 2-6), Ca3 gave predominantly Si2O7(SiMe3)x(Pri)6-x (x = 2-6), and Ca3 gave predominantly Si3O9(SiMe3)x(Pri)6-x (x = 2-6) and Si3O10(SiMe3)x(Pri)8-x (x = 3-8).Mixed trimethylsilyl-isopropyl derivatives were converted to the fully trimethylsilylated derivatives SiO4(SiMe3)4, Si2O7(SiMe3)6, and Si3O10(SiMe3)8 on treatment with Amberlyst 15 ion-exchange resin in the presence of hexamethyldisiloxane.In the trimethylsilylation of Ca2 reaction of mineral itself is complete within ca. 6 min at room temparature, under the conditions employed, and the majority of unwanted side reactions which yield Si2O7 and Si3O10 derivatives occur during the first 3-4 min.Side reactions may be suppressed by increasing the proportion of isopropyl alcohol and decreasing that of Ca2 in the reagents.The presence of both isopropyl alcohol and chlorotrimethylsilane is necessary for reaction to occur.Isopropyl alcohol may be replaced by either ethyl alcohol or water, altough the yield is reduced.When isopropyl alcohol is replaced by water, only the fully trimethylsilylated derivatives are formed.The mechanism of the reaction is discussed and experimental conditions are described which gives highest yields of the desired products.
- Calhoun, Harry P.,Masson, Charles R.
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- O-Metalation of silanols and POSS silanols over Amberlyst-15 catalyst: A facile route to unsymmetrical siloxanes, borasiloxanes and germasiloxanes
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A simple and highly practical Amberlyst-catalyzed direct O-metalation of silanols, POSS silanols and alkoxysilanes under mild conditions is proposed. This protocol can be applied to the synthesis of a wide range of important organosilicon derivatives such as siloxanes, germasiloxanes, borasiloxanes and functionalized silsesquioxanes. It is worth noting that Amberlyst-15 can be reused for further experiments and its catalytic activity in this process is well-preserved for several recycling steps.
- Kuciński, Krzysztof,Hreczycho, Grzegorz
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supporting information
p. 261 - 266
(2019/03/27)
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- MANUFATURING METHOD FOR TETRAKIS(TRIALKYLSILYLOXY) SILANE, SEMICONDUCTOR THIN FILM HAVING POLYMER DERIVED FROM TETRAKIS(TRIALKYLSILYLOXY) SILANE, AND MANUFATURING METHOD FOR SEMICONDUCTOR THIN FILM
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Provided by the present invention are: a method for producing tetrakis (trialkylsilyloxy) silane represented by chemical formula 3, Si(OSiR^2_3)_4, including reaction between a compound represented by chemical formula 1, Si(OR^1)_n(OSiR^2_3)_(4-n), and a compound represented by chemical formula 2, SiX(R^2)_3; a semiconductor thin film including a polymer derived from tetrakis (trialkylsilyloxy) silane; and a method of producing a semiconductor thin film. The definitions of formulas 1 and 2 are as described in the specification. The present invention is able to produce tetrakis (trialkylsilyloxy) silane having high purity.COPYRIGHT KIPO 2019
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Paragraph 0064; 0097-0102; 0104
(2019/10/11)
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- A four (three-siloxy) silicon synthetic method (by machine translation)
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This invention relates to a four (three-siloxy) silicon synthetic method, which belongs to the technical field of fine chemicals. The invention is firstly to silicon tetrachloride and trimethylchlorosilane according to the proportion in the input to the reactor, adding catalyst, stirring ice-[...] water reaction reactant layered, washing, drying and then distilled, to obtain four (three-siloxy) silicon product. The invention four (three-siloxy) silicon product content is high, the yield is high, production cost is very low, few by-products, environmental pollution is small. (by machine translation)
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Paragraph 0009; 0010; 0011; 0012; 00013; 0014; 0015-0022
(2018/03/28)
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- Synthetic process of tetra-(trimethyl silica group) silane
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The invention relates to a synthetic process of tetra-(trimethyl silica group) silane and belongs to the field of organic synthetic chemistry. According to the invention, tetra-(trimethyl silica group) silane is produced by reaction under the condition of an acid catalyst by taking silicon tetrachloride and hexamethyldisiloxane as materials. After reaction is ended, vacuum filtration and standingfor layering are performed, an upper-layer solution is collected, trimethylchlorosilane is distilled out at normal pressure, and then reduced pressure distillation is performed to obtain an excessivehexamethyldisiloxane material and a tetra-(trimethyl silica group) silane product. The synthetic process has the advantages of being simple in operation of the production process, low in production cost, easy for separation, high in yield and good in quality, and having product content reaching 99.0% or above, tri-substituted byproduct content reaching 0.1% or below, and mole yield reaching 96.8%or above.
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Paragraph 0013-0020
(2018/05/15)
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- BRANCHED ORGANOSILOXANES USED AS HEAT TRANSFER FLUID
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The invention relates to a method for operating a system at an operating temperature of between 300° C. and 500° C., using a heat transfer fluid comprising branched siloxanes of general formula (I) (R3SiO1/2), (SiO4/2) in which w represents integral values of between 4 and 20, z represents integral values of between 1 and 15, and R represents a methyl group, the sum of the fractions of all siloxanes of general formula (1) being at least 95 mass %, in relation to the whole heat transfer fluid.
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Paragraph 0036; 0037; 0048; 0049
(2018/02/06)
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- Protecting and Leaving Functions of Trimethylsilyl Groups in Trimethylsilylated Silicates for the Synthesis of Alkoxysiloxane Oligomers
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The concept of protecting groups and leaving groups in organic synthesis was applied to the synthesis of siloxane-based molecules. Alkoxy-functionalized siloxane oligomers composed of SiO4, RSiO3, or R2SiO2 units were chosen as targets (R: functional groups, such as Me and Ph). Herein we describe a novel synthesis of alkoxysiloxane oligomers based on the substitution reaction of trimethylsilyl (TMS) groups with alkoxysilyl groups. Oligosiloxanes possessing TMS groups were reacted with alkoxychlorosilane in the presence of BiCl3 as a catalyst. TMS groups were substituted with alkoxysilyl groups, leading to the synthesis of alkoxysiloxane oligomers. Siloxane oligomers composed of RSiO3 and R2SiO2 units were synthesized more efficiently than those composed of SiO4 units, suggesting that the steric hindrance around the TMS groups of the oligosiloxanes makes a difference in the degree of substitution. This reaction uses TMS groups as both protecting and leaving groups for SiOH/SiO? groups.
- Yoshikawa, Masashi,Tamura, Yasuhiro,Wakabayashi, Ryutaro,Tamai, Misa,Shimojima, Atsushi,Kuroda, Kazuyuki
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supporting information
p. 13990 - 13994
(2017/10/31)
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- Method for producing polyimidesiloxane
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PROBLEM TO BE SOLVED: To provide a method for synthesizing siloxanes at will in good yield while maintaining high structural controllability, which can be applied to substrates having various substituents.SOLUTION: The method comprises reacting benzyloxysilanes and silicon halides in the absence of hydrogen using a catalyst comprising a transition metal or a compound thereof, preferably a metal of group 9 or group 10 of the periodic table or a compound thereof. Thereby, corresponding siloxanes can be produced safely and simply in high yield under a mild reaction condition accompanied by elimination of a benzyl halide. Especially, by using an active carbon-supported catalyst as a heterogeneous catalyst, the target siloxanes can be separated easily.
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Paragraph 0039
(2018/10/16)
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- An efficient catalytic approach for the synthesis of unsymmetrical siloxanes
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The potential for expanding the variety of catalytic methods for siloxane bond formation is explored. Alkoxysilanes react with methylallylsilanes in the presence of scandium(III) trifluoromethanesulfonate to yield disiloxanes and isobutene. The reaction p
- Hreczycho, Grzegorz
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- In a method of manufacturing a condition anhyride silanolated
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PROBLEM TO BE SOLVED: To provide a method capable of synthesizing silanol under an anhydrous condition and a mild condition, adapting to substrates having various substituents, and producing siloxanes freely at an excellent yield, while having high structure controllability.SOLUTION: By a hydrogen addition reaction in which benzyloxy-substituted silanes are used as a silanol precursor, and a metal in the group 9 or 10 on the periodic table or a metal compound is used as a catalyst, corresponding silanols can be produced safely and easily at a high yield under an anhydrous condition and a mild condition, and especially object silanols can be isolated easily by using a carbon-carrying catalyst.
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Paragraph 0035
(2018/03/24)
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- Pd/C-catalyzed cross-coupling reaction of benzyloxysilanes with halosilanes for selective synthesis of unsymmetrical siloxanes
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A new protocol for the nonhydrolytic synthesis of unsymmetrical siloxanes has been developed. The cross-coupling reaction of benzyloxysilanes with halosilanes catalyzed by Pd/C afforded various unsymmetrical siloxanes with co-production of benzyl halides. the Partner Organisations 2014.
- Igarashi, Masayasu,Kubo, Keiko,Matsumoto, Tomohiro,Sato, Kazuhiko,Ando, Wataru,Shimada, Shigeru
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p. 19099 - 19102
(2014/05/20)
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- Silylation of silanols with vinylsilanes catalyzed by a ruthenium complex
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A new ruthenium complex-catalyzed O-silylation of silanols with vinylsilanes leading to siloxane bond formation with the evolution of ethylene is described. A maximum conversion of silanol is reached using an excess of vinylsilane to also yield the product of the homo-coupling of the latter. Under the optimum conditions, when vinylsilane with at least one ethoxy substituent is used, the reaction gives exclusively unsymmetrical siloxanes.
- Marciniec, Bogdan,Pawlu?, Piotr,Hreczycho, Grzegorz,Macina, Anna,Madalska, Martyna
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p. 1310 - 1313
(2008/09/18)
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- COSMETIC PREPARATION
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A cosmetic, wherein the cosmetic comprises tetraquistrimethylsiloxysilane represented by the formula (1)[(CH)SiO]Si The cosmetic has an excellent sensory properties and stability.
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Page/Page column 14-16
(2010/02/15)
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- Preparation of branched siloxane
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By reacting a branched siloxane compound of formula (2) containing compounds of formula (1) as an impurity with a disiloxane compound of formula (3) in the presence of an acid compound, there is prepared a branched siloxane of formula (2) containing a reduced level of compounds of formula (1).R1?nSi(OSiR2?3)3-n(OR3)R1?nSi(OSiR2?3)4-nR2?3SiOSiR2?3 R1 is a monovalent hydrocarbon group, R2 and R3 are H or monovalent hydrocarbon groups, and n is 0 or 1.
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Page/Page column 13-14
(2010/02/10)
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- Titanium Alkoxy Derivatives as Catalysts of Heterofunctional Condensation of Alkoxy- and Acyloxysilanes
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The catalytic activity of titanium alkoxy derivatives of various structures in heterofunctional condensation of alkoxy- and acyloxysilanes was studied by the kinetic method. The correlation between the catalytic activity and chemical transformations of the titanium compounds in the course of the reaction was demonstrated.
- Suvorov,Khonina,Kozlov,Kochneva
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p. 589 - 592
(2007/10/03)
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- TRIMETHYLSILYLATION OF SYNTHETIC SILICATES WITH ACETOXYTRIMETHYLSILANE
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It was shown that acetoxytrimethylsilane can be used as a silylating agent in the preparation of oligoorganosilicates from natural and synthetic silicates.The optimum medium for conducting the silylation of silicates is an acetic acid solution of DMF, and the yield of the target product is inversely proportional to the amount of silicate in the reaction mixture.
- Kalmychkov, G. V.,Yarosh, N. K.,Mirskov, R. G.,Voronkov, M. G.,Rakhlin, V. I.
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p. 506 - 509
(2007/10/02)
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- TRIMETHYLSILYLATION OF SYNTHETIC SILICATES WITH TRIMETHYLACETOXYSILANE
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It is shown that trimethylacetoxysilane can be used as a silylating agent for the preparation of oligoorganosilicates from natural and synthetic silicates.Acetic acid solutions of dimethylformamide are optimum media for the silylation of the silicates, the yield of the products being in inverse proportion to the amount of the silicate in the reaction mixture.
- Kalmychkov, G. V.,Yarosh, N. K.,Mirskov, R. G.,Voronkov, M. G.,Rakhlin, V. I.
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p. 1881 - 1883
(2007/10/02)
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- Process for preparing organosiloxanes
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Organosiloxanes (1) of the general formula in which R is the same or different and represents a hydrogen atom or a monovalent hydrocarbon radical having from 1 to 18 carbon atom(s) per radical or a substituted monovalent hydrocarbon radical having from 1 to 18 carbon atom(s) per radical, R1 represents R or a chlorine atom, and n is 3 or 4, are prepared by reacting organodisiloxanes (2) of the general formula with chlorosilanes (3) of the general formula in which R and n are the same as above, in the presence of phosphonitrile chlorides (4) and cocatalysts (5), in which the cocatalysts (5) are used concomitantly with the phosphonitrile chlorides (4) and are selected from the group consisting of amides of the general formula in which R2 is the same or different and represents a hydrogen atom or a monovalent hydrocarbon radical having from 1 to 8 carbon atom(s) per radical or a substituted monovalent hydrocarbon radical having from 1 to 8 carbon atom(s) per radical, and X reresents a radical of the formula R22 N- or STR1 where R2 is the same as above, R3 represents a divalent hydrocarbon radical having from 5 to 7 carbon atoms per radical, urea or urea derivatives of the general formula where X is the same as above and cyanuric acid.
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- Siloxane basicity toward strong acid in nonpolar solution
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The relative basicities of ten siloxanes and an ether were studied in benzene by determining from visible spectroscopic measurements the thermodynamic constants for the competition between the substrate and a reference base (4-chloro-2-nitroaniline) for acid (trifluoromethanesulfonic acid): RB-HA + S ? RB + S·HA. The Keq values were considered as a measure of basicity with the following order established and explained by inductive effects in the protonated species: permethyl linear siloxanes (Me3Si(OSiMe2)nOSiMe3, n = 0-3) > dibutyl ether > HMe2SiOSiMe2H > branched siloxanes ((Me3SiO)3SiMe, (Me3SiO)4Si) > cyclic siloxanes ((Me2SiO)n, n = 3-5). The ΔH and ΔS values were positive and increased with higher basicity; this behavior was attributed to differential solvation of ion pairs.
- Shepherd, Brian D.
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p. 5581 - 5583
(2007/10/02)
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- Method for the cleavage of organic siloxanes, and products and applications thereof
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A method for the cleavage of organosiloxanes with chlorosilanes in the presence of ferric chloride and hydrogen chloride as catalysts resulting in chloroalkyl silanes or chloroaryl silanes, and organosiloxanes, which are characterized by one or more --O--Si--R3 groups, (R=alkyl or aryl), which are directly bound to a silicon atom which in turn is bound either to the same grouping or to an alkyl or aryl moiety.
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- Treatment of Tetraalkoxysilanes with Amberlyst 15 Cation-Exchange Resin in Presence of Hexamethyldisiloxane
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Tetraalkoxysilanes were treated with Amberlyst 15 cation-exchange resin in hexamethyldisiloxane at 40 deg C in order to substitute the trimethylsilyl group for the alkyl group in a tetraalkoxysilane partially.Tetramethoxy-, ethoxy-, propoxy-, and butoxysilanes were used for the experiments.After the treatment, SiO4R(4-n)Xn (1 /= n /= 4, R = CH3, C2H5, n-C3H7, and n-C4H9, X = Si(CH3)3) were detected by gas chromatography-mass spectrometry.The degree of trimethylsilylation of tetraalkoxysilane changed with the molar ratio of hexamethyldisiloxane to tetraalkoxysilane and quantities of the reaction products in the system depended mainly on the ratio.
- Hasegawa, Isao,Sakka, Sumio
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p. 4313 - 4316
(2007/10/02)
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- Preparation of Alkyl-substituted Partial Trimethylsilyl Silicates from Olivine
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The direct trimethylsilylation reaction of olivine has yielded partial trimethylsilyl derivatives of ortho- and di-silicates whose unsilylated silanol groups have been esterified with the alcohol used as the organic solvent in the trimethylsilylating reagent.Gas chromatographic-mass spectroscopic measurements indicate the presence of the tri-, di-, and mono-alkyl-substituted trimethylsilyl derivatives of monosilicic acid in addition to the fully silylated monomeric derivative .Dimeric derivatives have also been detected which contain both the completely trimethylsilylated derivative and alcohol-esterified derivatives .The ratio of the esterified products varies with the volume of alcohol or water in the silylating reagent as well as the reaction time.
- Kuroda, Kazuyuki,Koike, Tetsuhiro,Kato, Chuzo
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p. 1957 - 1960
(2007/10/02)
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