- One-Step Synthesis of Siloxanes from the Direct Process Disilane Residue
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The well-established Müller–Rochow Direct Process for the chloromethylsilane synthesis produces a disilane residue (DPR) consisting of compounds MenSi2Cl6?n(n=1–6) in thousands of tons annually. Technologically, much effort is made to retransfer the disilanes into monosilanes suitable for introduction into the siloxane production chain for increase in economic value. Here, we report on a single step reaction to directly form cyclic, linear, and cage-like siloxanes upon treatment of the DPR with a 5 m HCl in Et2O solution at about 120 °C for 60 h. For simplification of the Si?Si bond cleavage and aiming on product selectivity the grade of methylation at the silicon backbone is increased to n≥4. Moreover, the HCl/Et2O reagent is also suitable to produce siloxanes from the corresponding monosilanes under comparable conditions.
- Neumeyer, Felix,Auner, Norbert
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supporting information
p. 17165 - 17168
(2016/11/23)
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- Method of purifying organosilicon compositions used as precursors in chemical vapor deposition
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The present invention provides a method for purifying an organosilicon composition comprising an alkoxysilane or a carboxysilane and a basic impurity, the method comprising the steps of: contacting the organosilicon composition with an acid gas to form a precipitate comprising a salt of the acid gas upon reaction with the basic impurity; and removing the salt of the acid gas to form a purified organosilicon product.
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Page/Page column 7-8
(2008/12/07)
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- REDUCTION SELECTIVE DE COMPOSES CARBONYLES PAR CATALYSE HETEROGENE A LA SURFACE DES SELS
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The reduction of carbonyl compounds carried out with ethoxyhydrogenosilanes and alkali metal fluorides as catalysts and without solvent is highly selective.The reactivity order is aldehyde> ketone> ester.The reduction of aldehydes is possible in the presence of ketones, and of ketones in the presence of esters.The keto-group in a keto-ester can be selectively reduced.The high selectivity of this system is due to three factors: hydrogenosilane reactivity (EtO)2SiMeH (EtO)3SiH, nature of the salt (KFCsF) and temperature.Chlorides, amides, anhydrides and ethylenic, bromo, nitro groups are not reduced.This enables the selective reduction of the carbonyl group in bifunction compounds.
- Boyer, J.,Corriu, R. J. P.,Perz, R.,Reye, C.
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p. 2165 - 2172
(2007/10/02)
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