7291-09-0Relevant articles and documents
Tris(hydridosilylethyl)boranes: Highly reactive synthons for polymeric silicon compounds
Weinmann, Markus,Kamphowe, Thomas W.,Fischer, Peter,Aldinger, Fritz
, p. 115 - 127 (1999)
Two methods for the synthesis of tris(hydridosilylethyl)boranes B[C2H4Si(CH3)nH3-n] 3 (C2H4 = CHCH3, CH2CH2; n = 0, 1, 2; 5a-c) are reported. In the first route, tris(chlorosilylethyl)boranes B[C2H4Si(CH3)nCl3-n] 3 (n = 0, 1, 2; 3a-c) are reacted with LiAlH4 in diethyl ether solution. Compounds 3a-c are prepared by hydroboration of the respective vinyl chlorosilanes (H2C=CH)Si(CH3)nCl3-n (n = 0, 1, 2; 1a-c) with borane dimethylsulfide, BH3·S(CH3)2. Hydroboration of hydrido vinylsilanes (H2C=CH)Si(CH3)nH3-n (n = 0, 1, 2; 6a-c) with BH3·S(CH3)2 represents an alternative route, which produces 5a-c in much higher yield. The intermediates 6a-c are obtained from 1a-c and LiAlH4 in diethyl ether solution and, because of their difficult handling, reacted in situ. Detailed NMR studies prove boron addition to the olefinic moieties to be not regioselective, since resonance signals for products formed by α- and β-boron addition to the vinyl functions are observed. The elemental constitution of 5a-c is established by high-resolution electron ionization mass spectrometry for both the molecular ion peak and a series of fragment ions. Major fragments arise from C-C bond formation in the gas phase between two of the boron side chains in the ion dipole complex.
Infrared and Raman spectra, conformational stability, barriers to internal rotation, normal-coordinate calculations and vibrational assignments for vinyl silyl bromide
Guirgis, Gamil A.,Nashed, Yasser E.,Durig, James R.
, p. 1065 - 1078 (2000)
The infrared (3200-30 cm-1) spectra of gaseous and solid, the Raman spectra (3200-30 cm-1) of the liquid and solid vinyl silyl bromide, CH2CHSiH2Br, have been recorded. Additionally, quantitative depolarization values have been obtained. Both the gauche and cis conformers have been identified in the fluid phases but only the gauche conformer remains in the solid. Variable temperature studies from 0 to -87 °C of the Raman spectrum of the liquid was carried out. From these data, the enthalpy difference has been determined to be 22±6 cm-1 (0.26±0.08 kJ/mol), with the gauche conformer being the more stable form. The predictions from the ab initio calculations up to MP2/6-311++G(2d,2p) basis set favor the gauche as the more stable form. A complete vibrational assignment is proposed for both the gauche and cis conformers based on infrared band contours, relative intensities, depolarization values and group frequencies. The vibrational assignments are supported by normal coordinate calculations utilizing the force constants from ab initio MP2/6-31G(d) calculations and the potential energy terms for the conformer interconversion have been obtained from the same calculations. Complete equilibrium geometries have been determined for both rotamers by ab initio calculations employing a variety of basis sets up to 6-311++G(2d,2p) at levels of restricted Hartree-Fock (RHF) and/or Moller-Plesset (MP) to second order. The results are discussed and compared to those obtained for some similar molecules.
Mechanism of the Thermal Decomposition of Ethylsilane
Jardine, R. E,,O'Neal, H. E.,Ring, M. A.,Beatie, M. E.
, p. 12507 - 12511 (1995)
Products and kinetics of the thermal decomposition of ethylsilane, under static system conditions, are reported.Both neat and propylene-inhibited reactions follow silylene chain mechanisms.Modeling fits to product yield and reactant loss data establish approximate values for the rate constants of the ethylsilylene decomposition to ethylene and silylene (k2 ca. 2 x 106 s-1) and the ethylsilylene isomerization to vinylsilane (k8 ca 5 x 102 s-1), both at 723 K.RRKM and thermochemical analyses of these results yield values for the high-pressure activation energy of the ethylsilylene decomposition (EtSiH C2H4 + SiH2) of E2 = 25.0 kcal/mol and a heat of formation for ethylsilylene of ΔHf(EtSiH) = 47.7 +/- 2.5 kcal/mol.An enthalpy group additivity for the methylene group in organosilanes and organosilylenes of ΔHf = -1.3 +/- 2 kcal/mol is deduced as well as the activation energy of the isomerization of ethylsilylene to vinylsilane (EtSiH CH2=CHSiH3) of E8 = 35.6 +/- 2 kcal/mol.
GASEOUS DIELECTRICS WITH LOW GLOBAL WARMING POTENTIALS
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, (2010/12/31)
A dielectric gaseous compound which exhibits the following properties: a boiling point in the range between about ?20° C. to about ?273° C.; non-ozone depleting; a GWP less than about 22,200; chemical stability, as measured by a negative standard enthalpy of formation (dHf0); a toxicity level such that when the dielectric gas leaks, the effective diluted concentration does not exceed its PEL; and a dielectric strength greater than air.
Compounds which mimic the chemical and biological properties of discodermolide
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, (2008/06/13)
Compounds which mimic the chemical and/or biological activity of discodermolide are provided and intermediates useful in their preparation.
Compounds which mimic the chemical and biological properties of discodermolide
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, (2008/06/13)
Compounds which mimic the chemical and/or biological activity of discodermolide are provided and intermediates useful in their preparation.
Synthetic techniques and intermediates for polyhydroxy, dienyl lactone derivatives
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, (2008/06/13)
Synthetic methods for lactone-containing compounds such as the discodermolides are provided, as are compounds which mimic the chemical and/or biological activity thereof, and methods and intermediates useful in their preparation.
Reaction of Hydrogen Peroxide with Organosilanes under Chemical Vapour Deposition Conditions
Moore, Darren L.,Taylor, Mark P.,Timms, Peter L.
, p. 2673 - 2678 (2007/10/03)
When a stream of vapour at low pressure which contained a mixture of H2O2 with an organosilane, RSiH3 (R = alkyl or alkenyl), impinged on a silicon wafer, deposition of oxide films of nominal composition RxSiO(2-0.5x), where x 3 or higher alkenyl groups. or higher alkenylgroups. Possible mechanism for the Si-C bond cleavage reaction are discussed, with energetic rearrangement of radical intermediates of type Si(H)(R)(OOH)' being favoured.
Synthetic techniques and intermediates for polyhydroxy, dienyl lactone derivatives
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, (2008/06/13)
Synthetic methods for lactone-containing compounds such as the discodermolides are provided, as are compounds which mimic the chemical and/or biological activity thereof, and methods and intermediates useful in their preparation.
Preparation of vinylsilane from monosilane and vinyl chloride
Itoh, Masayoshi,Iwata, Kenji,Kobayashi, Mineo
, p. 36 - 41 (2007/10/03)
Vinylsilane (CH2=CH-SiH3) was prepared by the dehydrochlorination reaction between SiH4 and vinyl chloride. The reactions were carried out in the gas phase at 450-500°C using a tube reactor, and the maximum yield of vinylsilane was 21% when the conversion of SiH4 was 32%. A small amount of CCl4 and CH3NO2 accelerated the reaction. A reaction mechanism involving :SiH2, which was generated by the thermal decomposition of SiH4, was proposed.
