- PROCESSES FOR SYNTHESIZING UNSYMMETRICAL DISILOXANES
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Described herein are methods for making alkenyl disiloxanes, comprising combining an alkenyl halosilane with an alkyl halosilane and adding the mixture to water, an acidic aqueous solution, or a basic aqueous solution. The ratio of the alkenyl halosilane to the alkyl halosilane is about 10:1 to about 1:10. The alkenyl halosilane and the alkyl halosilane are mixed at about 20 °C to about 45 °C. The reaction product is separated and washed with saturated alkali carbonate solution.
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Paragraph 0047-0048
(2021/06/22)
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- Preparation method of 1-vinyl-1,1,3,3,3-pentamethyldisiloxane
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The invention relates to a preparation method of 1-vinyl-1,1,3,3,3-pentamethyldisiloxane, prepared by: using 1,3-divinyl-1,1,3,3,-tetramethyldisiloxane ad 1,1,1,3,3,3-hexamethyldisiloxane as materials, carrying out rearrangement reaction under the catalytic action of a complexing catalyst KOH/18-crown ether-6; neutralizing the catalyst, filtering, and distilling filtrate. The macromolecular ring compound 18-crown ether-6 and KOH form the complexing agent; the compound reaction helps improve catalyst activity and efficiently catalyzes for rearrangement reaction. The macromolecular ring compound18-crown ether-6 and KOH form a complexing catalyst; complexing reaction is performed to obtain improved catalyst activity, and rearranging reaction is efficiently catalyzed. In addition, the preparation method is simple, the reacting is fast and stable, and the preparation method has the advantages of high yield, good safety, good environmental friendliness and the like.
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Paragraph 0039-0041
(2018/09/11)
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- Reaction of 1-hydrohexafluoroisobutenyloxytrimethylsilane with fluoride ion sources. 2,2,2′,2′-Tetrakis(trifluoromethyl)divinyl ether
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The reaction of 1-hydrohexafluoroisobutenyloxytrimethylsilane (2a) with cesium fluoride in diglyme leads to elimination of trimethylfluorosilane to form the 1-hydrohexafluoroisobutenolate anion (3), which is silylated with trialkylchlorosilanes at the oxygen atom. In the presence of bis(trifluoromethyl)ketene N,N,O-trimethylaminoacetal or N-(α,α- difluoroalkyl)-dialkylamines, silane 2a is transformed into 2,2,2′, 2′-tetrakis(trifluoromethyl)divinyl ether. The reaction of trifluoroacetic anhydride with N-(1,1,2,2-tetrafluoroethyl)diethylamine affords trifluoroacetyl fluoride in quantitative yield.
- Volkonskii,Kagramanova,Mysov,Mysova
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p. 2774 - 2781
(2007/10/03)
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