2351-34-0Relevant articles and documents
Benzocyclobutene/vinylphenyl-introduced polycarbosilanes with low dielectric constant, high temperature performance and photopatternability
Hu, Huan,Liu, Lili,Li, Zheng,Zhao, Cuijiao,Huang, Yawen,Chang, Guanjun,Yang, Junxiao
, p. 58 - 66 (2015)
With the development of microelectronic industry, low dielectric-constant insulating materials with high temperature performance and photopatternability have aroused interest. In this work, a kind of benzocyclobutene/vinylphenyl-introduced polycarbosilane
Infrared and Raman spectra, conformational stability, normal coordinate analysis, ab initio calculations, and vibrational assignment of 1-fluoro-1-methylsilacyclobutane
Guirgis, Gamil A.,Gounev, Todor K.,Zhen, Pengqian,Durig, James R.
, p. 2753 - 2769 (1999)
The infrared (3500-40 cm-1) spectra of gaseous and solid 1-fluoro-1-methylsilacyclobutane, c-C3H6SiF(CH3), have been recorded. Additionally, the Raman spectrum (3500-30 cm-1) of the liquid has been recorded and quantitative depolarization values have been obtained. Both the axial and equatorial (with respect to the methyl group) conformers have been identified in the fluid phases. Variable temperature (-55--100 °C) studies of the infrared spectra of the sample dissolved in liquid xenon have been carried out. From these data, the enthalpy difference has been determined to be 267±10 cm-1 (3.19±0.12 kJ mol-1), with the axial conformer being the more stable form and the only conformer remaining in the polycrystalline solid. A complete vibrational assignment is proposed for the axial conformer and many of the fundamentals for the equatorial conformer have also been identified. The vibrational assignments are supported by normal coordinate calculations utilizing ab initio force constants. Complete equilibrium geometries have been determined for both rotamers by ab initio calculations employing the 6-31G* and 6-311++G** basis sets at the 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.
Rhodium-Catalyzed Intermolecular Silylation of Csp?H by Silacyclobutanes
He, Tao,Li, Bin,Liu, Lichuan,Ma, Wenpeng,He, Wei
supporting information, p. 5648 - 5652 (2021/03/08)
The signature reactivity of silacyclobutane (SCB) is their cycloaddition reactions with various π bonds. Recently, the first cases were disclosed where SCBs reacted with both Csp2?H and Csp3?H σ bonds in an intramolecular fashion. Herein, it is reported that SCB is also an efficient reagent for Csp?H bond silylation. Thus, rhodium-catalyzed intermolecular reactions between SCBs and terminal alkynes produced a series of symmetrical and unsymmetrical tetraorganosilicons bearing a Csp?Si functionality. Preliminary studies suggested that the reaction did not involve a cycloaddition pathway, but instead a direct activation of Csp?H bonds.
Metallocene compounds, metallocene catalysts including the compounds and methods of polymerizing olefins with the catalysts
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, (2008/06/13)
There are disclosed new metallocene compounds and catalysts for olefin polymerization. The metallocene compound is a complex of transition metal and cyclopentadienyl-type ligands substituted with silacycloalkyl group. The metallocene catalyst comprises the above metallocene compound and at least one activator such as aluminoxanes, aromatic boron compounds substituted with fluoride, and modified clays. The metallocene catalyst can be used for polymerization of olefin in liquid phase, slurry phase or gas phase process.
