18162-48-6Relevant articles and documents
The recycling of organosilyl protecting species used in organic synthesis and the water binding ability of the silanol tBuMe2SiOH
Lickiss, Paul D.,Stubbs, Katharine M.
, p. 171 - 174 (1991)
The silanols formed on the cleavage of organosilyl protecting groups from organic compounds can be efficiently reconverted into the chlorosilanes used in the initial silylation reaction by treatment with SOCl2.The silanol tBuMe2SiOH is very readily removed from organic reaction mixtures as its remarkably volatile hemihydrate tBuMe2SiOH>2 * H2O.
First gas-phase generation of a cis chloroiminoarsane ClAs NSiMe and a cis chloroiminophosphane ClP NSiMe Bu. Characterization by photoelectron spectroscopy
Miqueu,Sotiropoulos,Pfister-Guillouzo,Romanenko
, p. 930 - 938 (2001)
Photoelectron spectroscopy-flash vacuum thermolysis in the gas phase allowed us to synthesize, for the first time, the cis forms of two weakly hindered, low-coordinate arsenic and phosphorus compounds (ClPn NSiR3; Pn = P, As), as well as to characterize them by their ionization energies. In order to assign the different bands in the PE spectra and to estimate the effect of the substituents SiMe3 and Cl on the electronic and structural properties of these compounds, we performed calculations using density functional theory (hybrid functional B3LYP) with the basis set 6-311G(d,p). The thermodynamic stabilization of these halogenated systems appears in the important antiperiplanar interactions between the nitrogen lone pair nNand the σ*AsCl (or σ*PCl) orbital. For these two compounds, in spite of a poor 2pπ(N)-3pπ(P)/4pπ(As) overlap, it was observed that the substitution of a chlorine atom on the pnictogen (As,P) and a silyl group on nitrogen (negative hyperconjugation) leads to a relatively high ionization energy for the πPn N orbital [IE(πPn N ≈ 10 eV].
Oxidation of Triorganosilanes and Related Compounds by Chlorine Dioxide
Grabovskiy, S. A.,Kabal’nova, N. N.
, p. 2391 - 2402 (2022/01/22)
Abstract: Oxidation of triethylsilane, tert-butyldimethylsilane, dimethylphenylsilane, triphenylsilane, 1,1,1,2tetramethyl-2-phenyldisilane, tris(trimethylsilyl)silane, hexamethyldisilane, tetrakis(trimethylsilyl)silane, 1,1,3,3tetraisopropyldisiloxane with chlorine dioxide was carried out. The reaction products of studied triorganosilanes with chlorine dioxide in an acetonitrile solution were the corresponding silanols and siloxanes. A mechanism explaining the formation of products and the observed regularities of the oxidation of silanes with chlorine dioxide has been proposed. A thermochemical analysis of some possible pathways in the gas phase using methods G4, G3, M05, and in an acetonitrile solution by the SMD-M05 method was carried out. The oxidation process can occur both with the participation of ionic and radical intermediates, depending on the structure of the oxidized substrate and medium.
Hexachloroethane: a highly efficient reagent for the synthesis of chlorosilanes from hydrosilanes
Pongkittiphan, Veerachai,Theodorakis, Emmanuel A.,Chavasiri, Warinthorn
scheme or table, p. 5080 - 5082 (2009/12/01)
A new and efficient chlorination protocol is presented for the preparation of chlorosilanes from hydrosilanes. A variety of chlorinating agents in combination with palladium(II) chloride as the catalyst are examined. Among them, hexachloroethane is found to be the best choice, furnishing the desired product in good to quantitative yields under mild conditions. Various hydrosilanes are used as starting materials to explore the scope of this reaction.
The synthesis of chlorosilanes from alkoxysilanes, silanols, and hydrosilanes with bulky substituents
Masaoka, Shin,Banno, Tadashi,Ishikawa, Mitsuo
, p. 174 - 181 (2007/10/03)
We have found that commercially important trialkylchlorosilanes can readily be synthesized by the reaction of alkoxysilanes, silanols, and hydrosilanes with aqueous concentrated hydorochloric acid. Treatment of trialkylalkoxysilanes bearing the bulky alkyl substituents, such as the i-Pr, sec-Bu, tert-Bu, and cyclo-Hex group, with 35% aqueous hydrochloric acid afforded the corresponding trialkylchlorosilanes in excellent yields. Similar treatment of trialkylsilanols with 35% aqueous hydrochloric acid also gave trialkylchlorosilanes in almost quantitative yields. The reaction of methyltrichlorosilane and dimethyldichlorosilane with alkyl-Grignard reagents bearing a bulky alkyl group, followed by treatment of the resulting mixtures with aqueous concentrated hydrochloric acid, produced the respective dialkylmethyl- and alkyldimethylchlorosilanes in high yields. Treatment of trialkylhydrosilanes with concentrated hydrochloric acid in the presence of a palladium catalyst afforded trialkylchlorosilanes in high yields.
Production processes for triorganomonoalkoxysilanes and triorganomonochlorosilanes
-
Page/Page column 27, (2008/06/13)
A silane containing a bulky hydrocarbon group or groups R therein and having the formula (III) [in-line-formulae]R3-(x+y)(R1)x(R2)ySi(OR3) [/in-line-formulae] can be produced by reacting a silane of the formula (I) [in-line-formulae](R1)x(R2) ySiCl3-(x+y)(OR3) [/in-line-formulae] with a Grignard reagent of the formula (II) [in-line-formulae]RMgX [/in-line-formulae] Further, a tri-organo-chlorosilane of the formula (XIIa) [in-line-formulae](R1)(R2)(R3)SiCl [/in-line-formulae] can be produced by reacting a tri-organo-silane of the formula (XIa) [in-line-formulae](R1)(R2)(R3)SiZ1 [/in-line-formulae] with hydrochloric acid. Furthermore, a tri-organo-monoalkoxysilane of the formula (XXIII) [in-line-formulae]R3-(x+y)(R1)x(R2)ySi(OR3) [/in-line-formulae] can be produced when a silane of the formula (XXI) [in-line-formulae](R1)x(R2)ySiCl4-(x+y) [/in-line-formulae] is reacted with a Grignard reagent of the formula (XXII) [in-line-formulae]RMgX [/in-line-formulae] with addition of and reaction with an alcohol or an epoxy compound during the reaction.
Selective synthesis of halosilanes from hydrosilanes and utilization for organic synthesis
Kunai, Atsutaka,Ohshita, Joji
, p. 3 - 15 (2007/10/03)
Selective synthesis of halosilanes has been examined. Various types of halosilanes and halohydrosilanes, such as R3SiX, R2SiHX, R2SiX2, RSiH2X, RSiHX2 (X=Cl, Br, F), were obtained by the reactions of the corresponding hydrosilanes with Cu(II)-based reagents selectively in high yields. This method could be also applied to the synthesis of chlorofluorosilanes and chlorohydrogermanes. On the other hand, iodo- and bromosilanes and germanes were obtained by Pd- or Ni-catalyzed hydride-halogen exchange reactions of hydrosilanes with alkyl or allyl halides. Their synthetic applications have been demonstrated by using iodo- and bromosilanes and chlorofluorosilanes.
Fluorescein-based metal sensors, and methods of making and using the same
-
, (2008/06/13)
The present invention is directed, in part, to fluorescein-based ligands for detection of metal ions, and methods of making and using the same.
Process for the preparation of silanes, with a tertiary hydrocarbon group in the a-position relative to the silicon atom
-
, (2008/06/13)
The invention relates to a process for the preparation of silanes of the general formula 1 by reaction of Grignard reagents of the general formula 2 with silanes of the general formula 3 wherein R denotes C1 - to C10 -hydrocarbon radicals optionally substituted by fluorine, chlorine or cyano radicals, R1, in the α-position relative to the silicon atom, denotes tertiary C4 - to C30 -hydrocarbon radicals optionally substituted by fluorine, chlorine or cyano radicals, X and X1 each denote chlorine, bromine or iodine, m denotes the values 2 or 3 and n denotes the values 1 or 2, in the presence of a transition metal catalyst and an inert, aprotic, and chelating compound.
Method for preparation of tertiary-hydrocarbylsilyl compounds
-
, (2008/06/13)
A method for the preparation of tertiary-hydrocarbylsilyl compounds. The method comprises contacting a mixture comprising diethylene glycol dibutyl ether, and a Grignard reagent described by formula RMgX with a silicon compound described by formula R1a SiX4-a, where R is a tertiary-hydrocarbyl group comprising four to about 20 carbon atoms, each R1 is an independently selected substituted or unsubstituted monovalent hydrocarbon group comprising one to about 20 carbon atoms, each X is an independently selected halogen atom, and a is an integer with a value of zero to three, in the presence of an effective amount of a copper compound catalyst. The present invention provides a method for making sterically hindered organosilicon intermediates useful in the pharmaceutical industry.
