2157-42-8Relevant articles and documents
Chemistry of Silicon-Nitrogen Compounds, CLXVI: Organylamino Substitutions on Hexachlorodisiloxane
Wannagat, Ulrich,Bogedain, Gabriele,Hajibegli, Hamid,Moretto, Hans-Heinrich
, p. 865 - 874 (1990)
Reaction of hexachlorodisiloxane with primary and secondary amines leads - in dependence of stoichiometry - to numerous partially and totally organylamino substituted disiloxanes.Partially aminosubstituted chlorodisiloxanes are very sensitive to moisture and can be converted into disiloxanes with different organylamino groups.Exhaustive alkanolysis substitutes amino as well as chloro groups giving hexaalkoxydisiloxanes, but partial alkanolysis may substitute amino in preference to chloro groups.Mass spectra can be interpreted by abstraction of RR'N., RR'N+, RR'NH and (RR'N minus H) units.Most of the compounds are colourless liquids but hexakis(piperidino)-disiloxane melts at 270 deg C.
A new route to silicon alkoxides from silica
Kemmitt, Tim,Henderson, William
, p. 1031 - 1035 (1998)
A novel route to tetraethoxysilane and other silicon alkoxides is described, from amorphous silica (SiO2·H2O) as the raw material. The reaction of amorphous silica with triethanolamine is enhanced by using an alkali metal hydroxide catalyst, to form a range of triethanolamine-substituted silatrane species. These can undergo alkoxide exchange in acidic alcohols to form alkoxysilatranes, tetraalkoxysilanes, hexaalkoxydisiloxanes and higher siloxanes. Reaction of triethanolamine-substituted silatranes with acetic anhydride produces acetoxysilatrane. Products were identified by multinuclear (1H, 13C and 29Si) magnetic resonance spectroscopy, electrospray mass spectrometry or high-resolution gas chromatography electron impact mass spectrometry.
BRANCHED ORGANOSILOXANES USED AS HEAT TRANSFER FLUID
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Paragraph 0036; 0037; 0050; 0051; 0052, (2018/02/06)
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.
Bis(acetylacetonato)Ni(II)/NaBHEt3-catalyzed hydrosilylation of 1,3-dienes, alkenes and alkynes
Srinivas, Venu,Nakajima, Yumiko,Ando, Wataru,Sato, Kazuhiko,Shimada, Shigeru
, p. 57 - 62 (2018/03/27)
The utility of commercially available Ni(II) salts, Ni(acac)2 (acac = acetylacetonato) (1a) and its derivatives bis(hexafluoroacetylacetonato)nickel(II) (1b) and bis(2,2,6,6-tetramethyl-3,5-heptanedionato)nickel(II) (1c) as versatile hydrosilylation catalyst precursors is described. Complexes 1a-c catalyze 1,4-selective hydrosilylation of 1,3-dienes in the presence of NaBHEt3 at ambient temperature. The reactions exhibit good regioselectivity to give the branched isomers as major products. The catalytic system also catalyzes hydrosilylation of alkenes including industriary important siloxy-, amino-, and epoxy-substituted ones as well as both terminal and internal alkynes.
