3047-74-3Relevant academic research and scientific papers
A novel photosensitive silicone ladder polymer: Synthesis, photochemical, and thermal characteristics
Yasuda, Naoki,Yamamoto, Shigeyuki,Adachi, Hiroshi,Nagae, Suguru,Wada, Yuji,Yanagida, Shozo
, p. 991 - 996 (2001)
A negative working photosensitive silicone ladder polymer (PVSQ) based on polyphenylsilsesquioxane with vinyl groups as a reactive substituents in the side chain, and 2,6-bis(azidobenzylidene)4-methylcyclohexanone (BA) as a photocrosslinker, has been developed. The monodisperse PVSQ was synthesized by co-polymerization of trichlorophenylsilane and trichloro(vinyl)silane with potassium hydroxide in isobutyl methyl ketone. The PVSQ film showed excellent transparency above 280 nm and high solubility in organic solvents. The photosensitive PVSQ containing 3 wt% of BA showed the sensitivity of 40 mJ cm-2 when it was exposed to 365 nm light (i-line) followed by development with a mixture solution of anisole and xylene at 25 °C. The photosensitive PVSQ film also showed high thermal stability (decomposition temperature: 520 °C) and low dielectric constant (3.2/1 MHz), demonstrating a high potential for application to LSI production.
Structural Control of Fully Condensed Polysilsesquioxanes: Ladderlike vs Cage Structured Polyphenylsilsesquioxanes
Choi, Seung-Sock,Lee, Albert S.,Hwang, Seung Sang,Baek, Kyung-Youl
, p. 6063 - 6070 (2015)
Through fine-tuning of the myriad of reaction conditions for an aqueous base-catalyzed hydrolysis-polycondensation reaction, a facile synthesis of structurally controlled polyphenylsilsesquioxanes was developed. Mechanism and kinetic studies indicated that the condensation reaction proceeded through a T1 structured dimer, which was quantitatively and in situ formed through mild hydrolysis of a phenyltrimethoxysilane (PTMS) monomer, to give either the cage-structured polyhedral oligomeric silsesquioxanes (POSS) or the corresponding ladderlike silsesquioxane (LPSQ) with excellent yields. Ladderlike and POSS materials were selectively achieved at higher and lower initial concentrations of PTMS, respectively, and an in-depth spectroscopic analysis of both compounds clearly revealed their structural differences with different molecular weights.
Transparent red -emitting silicone resin for color conversion and encapsulation of NUV light-emitting diodes
Chen, Hong,Wang, Yao,Lin, Jianhui,Shuai, Minmin,Zhu, Haidi,Zhang, Wengong,Ling, Qidan
, p. 2718 - 2726 (2019)
Herein, a novel transparent phenyl vinyl silicone resin nanocomposite containing exfoliated fluorescent Eu-containing hydrotalcite-like compound (EFHSN) is developed to serve as a dual role of color conversion and encapsulation material. Excited by near-NUV light, the EFHSN emits a strong characteristic red light (614?nm). Meanwhile, the EFHSN shows not only excellent transparency (T?>?95%) in the UV-Vis region and high refractive index (1.46) but also superior thermal stability, which could meet the need of commercial encapsulation materials and optical application. Therefore, the EFHSN is expected to be used in InGaN-based NUV light-emitting diodes and flexible optoelectronic device.
Ruthenacyclic Carbamoyl Complexes: Highly Efficient Catalysts for Organosilane Hydrolysis
Barik, Chandan Kr,Ganguly, Rakesh,Li, Yongxin,Leong, Weng Kee
, p. 4982 - 4986 (2018)
The ruthenacyclic carbamoyl complexes [RuX{2-NHC(O)C5H3NR}(CO)2(NCMe)] (R = H and Me; X = Br and SC6H3-o,o-Me2) are excellent catalysts for the hydrolysis of organosilanes, particularly towards primary silanes, generating hydrogen under ambient conditions within seconds. These complexes are structural mimics of the [Fe]-hydrogenase active site and like the natural enzyme, a labile ligand at the sixth coordination site is essential to the catalytic activity.
Kinetics and Mechanism of Hydrolysis of a Silicate Triester, Tris(2-methoxyethoxy)phenylsilane
McNeil, K. J.,DiCaprio, J. A.,Walsh, D. A.,Pratt, R. F.
, p. 1859 - 1865 (1980)
The kinetics of hydrolysis in dilute aqueous solution of tris(2-methoxyethoxy)phenylsilane to phenylsilanetriol have been studied.The hydrolysis exibits specific acid and general base catalysis, the latter with a Broensted β value of 0.7.The specific acid catalysis mechanism is probably A-2 (kH3O+/D3O+ = 1.24, ΔS = -39 cal deg-1 mol-1).At high pH (>10) the rate of appearance of the triol is limited by the rate of hydrolysis of one of the intermediates in the hydrolysis sequence, bis(2-methoxyethoxy)phenylsilanol, which, under these conditions, forms an inert anion.At lower pH the hydrolysis of bis(2-methoxyethoxy)phenylsilanol is several times faster than that of tris(2-methoxyethoxy)phenylsilane while that of the second intermediate, 2-methoxyethoxyphenylsilanediol, is probably faster than the above two hydrolyses at all pHs.It is argued that the form of general base catalysis observed suggests that the base-catalyzed reactions involve either an SN2**-Si or SN2*-Si mechanism with formation of a pentacoordinate intermediate.Generalization of the argument used here is explored.
METHOD FOR PRODUCING SILANOLS AND NOVEL SILANOLS
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Paragraph 0053-0054; 0059; 0087-0088, (2021/08/13)
PROBLEM TO BE SOLVED: To provide a method for efficiently producing silanols useful as functional chemicals, and to provide novel silanols. SOLUTION: There is provided a method for producing silanols including a reaction step of reacting alkoxysilanes having Si-OR bonds (R represents a hydrocarbon group having 1 to 6 carbon atoms) with water or heavy water in the presence of a catalyst, wherein a method for producing silanols having an Si-OR' bond (R' represents a hydrogen atom or a deuterium atom) is characterized in that the catalyst is an inorganic solid acid catalyst having a regular pore structure. There is also provided novel silanols obtained thereby. SELECTED DRAWING: None COPYRIGHT: (C)2021,JPOandINPIT
Synthesis of a Gold–Metal Oxide Core–Satellite Nanostructure for In Situ SERS Study of CuO-Catalyzed Photooxidation
Bai, Lu,Fan, Chenghao,Hu, Yanfang,Li, Yonglong,Liu, Jun,Shi, Faxing,Xie, Wei,Yang, Ling,Zhang, Kaifu,Zhao, Yaran
, p. 18003 - 18009 (2020/08/21)
This work reports on an assembling–calcining method for preparing gold–metal oxide core–satellite nanostructures, which enable surface-enhanced Raman spectroscopic detection of chemical reactions on metal oxide nanoparticles. By using the nanostructure, we study the photooxidation of Si?H catalyzed by CuO nanoparticles. As evidenced by the in situ spectroscopic results, oxygen vacancies of CuO are found to be very active sites for oxygen activation, and hydroxide radicals (*OH) adsorbed at the catalytic sites are likely to be the reactive intermediates that trigger the conversion from silanes into the corresponding silanols. According to our finding, oxygen vacancy-rich CuO catalysts are confirmed to be of both high activity and selectivity in photooxidation of various silanes.
Endogenous X-C=O species enable catalyst-free formylation prerequisite for CO2reductive upgrading
Dai, Wenshuai,Li, Hu,Saravanamurugan, Shunmugavel,Wu, Hongguo,Yang, Song
supporting information, p. 5822 - 5832 (2020/10/21)
CO2, the main component of greenhouse gas, is currently developed as a promising surrogate of carbon feedstock. Among various conversion routes, CO2undergoing catalytic reduction can furnish hydrogen/energy carriers and value-added chemicals, while specific metal-containing catalysts or organocatalysts are often prerequisite for smooth proceeding of the involved reaction processes. In this work, both formic acid and N-containing benzoheterocyclic compounds (including various benzimidazoles, benzothiazole, and benzoxazole) along with silanols could be synthesized with high yields (>90%) from catalyst-free reductive upgrading of CO2under mild conditions (50 °C). The endogenous X-CO species, derived from the N-methyl-substituted amide-based solvent [Me2N-C(O)-R], especially PolarClean, and O-formyl group [O-C(O)-H] of in situ formed silyl formate, were found to play a prominent promotional role in the activation of the used hydrosilane for reductive CO2insertion, as demonstrated by density functional theory (DFT) calculations and isotopic labeling experiments. Moreover, reaction mechanisms and condition-based sensitivity assessment were also delineated.
Silanol Compound, Composition, and Method for Producing Silanol Compound
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Paragraph 0182; 0184; 0188-0194; 0196; 0200; 0208, (2017/07/14)
The purpose of the present invention is to provide silanol compounds that can be used as raw materials of siloxane compounds and the like, and a composition of the silanol compounds, as well as to provide a production method that makes it possible to produce silanol compounds at excellent yield. A composition comprising 5 mass % to 100 mass % of a silanol compound represented by Formulas (A) to (C) can be prepared by devising to produce silanol compounds under water-free conditions, to produce silanol compounds in a solvent having the effect of suppressing the condensation of silanol compounds, and to perform other such processes, the composition being able to be used as a raw material or the like of siloxane compounds because the silanol compounds can be stably present in the resulting composition.
Trapping Aluminum Hydroxide Clusters with Trisilanols during Speciation in Aluminum(III)–Water Systems: Reproducible, Large Scale Access to Molecular Aluminate Models
Lokare, Kapil Shyam,Frank, Nicolas,Braun-Cula, Beatrice,Goikoetxea, Itziar,Sauer, Joachim,Limberg, Christian
supporting information, p. 12325 - 12329 (2016/10/13)
To gain molecular level insights into the properties of certain functions and units of extended oxides/hydroxides, suitable molecular model compounds are needed. As an attractive route to access such compounds the trapping of early intermediates during the hydrolysis of suitable precursor compounds with the aid of stabilizing ligands is conceivable, which was tested for the aluminum(III)/water system. Indeed, trisilanols proved suitable trapping reagents: their presence during the hydrolysis of AliBu2H in dependence on the amount of water used allowed for the isolation of tri- and octanuclear aluminum hydroxide cluster complexes [Al3(μ2-OH)3(THF)3(PhSi(OSiPh2O)3)2] (1) and [Al8(μ3-OH)2(μ2-OH)10(THF)3(p-anisylSi(OSiPh2O)3)4] (2). 1 can be regarded as the Al(OH)3cyclic trimer, where six protons have been replaced by silyl residues. While 2 features a unique [Al8(μ3-OH)2(μ2-OH)10]12+core. In contrast to most other known aggregates of this type, 1 and 2 can be readily prepared at reasonable scales, dissolve in common solvents, and retain an intact framework even in the presence of excessive amounts of water. This finding paves the way to future research addressing the reactivity of the individual functional groups.
