110577-10-1Relevant academic research and scientific papers
Geminal Di(hypersilyl) compounds - The synthesis and structure of bis[tris(trimethylsilyl)silyl]methanol
Gross, Thoralf,Kempe, Rhett,Oehme, Hartmut
, p. 1709 - 1714 (1997)
Tris(trimethylsilyl)silyllithium (1) reacts with methyl formate in diethyl ether (molar ratio 2:1) to give l,2-di(hypersilyl)ethylene 13. The formation of 13 proceeds through the intermediates formyl tris(trimethylsilyl)silane (4) and lithium bis[tris(trimethylsilyl)silyl]methoxide (5). In diethyl ether, the alkoxide 5 spontaneously eliminates lithium trimethylsilanolate thereby generating l,l-bis(trimethylsilyl)-2-[tris{trimethylsilyl)silyl]silene (9), which undergoes a formal [2+2] cycloaddition with the carbonyl compound 4 to afford 13. This was verified by crossover experiments. In pentane, the alkoxide 5 is moderately stable. Thus, the intermediate 5, prepared by reaction of 1 with tert-butyl formate in pentane, was protonated with water to give the di(hypersilyl)methanol 6 in good yield. The structure of 6 was elucidated by an X-ray crystal structure analysis, which expectedly revealed tremendous distortions of the molecular skeleton. Thus, the spatial demand of the two extended hemispherical (Me3Si)3Si groups forces a widening of the Si-C-Si angle at the central sp3 carbon atom to a value of 135.5°. WILEY-VCH Verlag GmbH, 1997.
Oxidative Dehydrogenative Silylation-Alkenation Reaction of Alkyl Aromatics with Silanes
Jiang, Wei,Zhang, Yongxin,Su, Yingpeng,Bao, Xiazhen,Fu, Ying,Huo, Congde
supporting information, p. 1065 - 1069 (2020/06/25)
A Cu(OAc)2/DDQ/DTBP/Py system catalyzed oxidative dehydrogenative silylation-alkenation tandem reaction of readily available alkyl aromatic compounds with silanes was established. A variety of functionalized alkenyl organosilicon compounds were provided in good to high yields with a total β-(E) selectivity. The control experiments revealed that the transformation might proceed through a radical pathway.
Electron Donor-Acceptor Complex Enabled Decarboxylative Sulfonylation of Cinnamic Acids under Visible-Light Irradiation
Ge, Qian-Qian,Qian, Jia-Sheng,Xuan, Jun
, p. 8691 - 8701 (2019/08/30)
Visible-light-induced decarboxylative sulfonylation of cinnamic acids with aryl sulfonate phenol esters enabled by the electron donor-acceptor complex is developed. The method offers a mild and green approach for the synthesis of vinyl sulfones with excellent functional group compatibility under photocatalyst and oxidant-free conditions.
Evaluation of cyclopentyl methyl ether (CPME) as a solvent for radical reactions
Kobayashi, Shoji,Kuroda, Hiroyuki,Ohtsuka, Yuta,Kashihara, Takashi,Masuyama, Araki,Watanabe, Kiyoshi
, p. 2251 - 2259 (2013/03/29)
We have explored the potential of cyclopentyl methyl ether (CPME) as a solvent for radical reactions. Hydrostannation, hydrosilylation, hydrothiolation, and tributyltin hydride mediated reductions were successfully carried out in CPME. GC-MS analysis indicated that CPME degraded into methyl pentanoate, cyclopentanone, 2-cyclopenten-1-ol, and cyclopentanol under thermal radical conditions, albeit only slightly. We also achieved radical-containing one-pot reactions in CPME as a demonstration of its applicability to multi-step reactions.
Allylsilanes in "tin-free" oximation, alkenylation, and allylation of alkyl halides
Rouquet, Guy,Robert, Frederic,Mereau, Raphael,Castet, Frederic,Landais, Yannick
, p. 13904 - 13911 (2012/01/15)
Tin-free oximation, vinylation, and allylation of alkyl halides have been developed by using allylsilanes as di-tin surrogates. Initiation of the radical process with a peroxide provides the silyl radical, which can abstract a halogen from the corresponding alkyl halide. The resulting carbon-centered radical then adds to various acceptors, including a sulfonyloxime, a vinylsulfone, and an allylsulfone, leading to formation of the desired products along with the corresponding allylsulfone resulting from the reaction of the PhSO2 radical with the allylsilane precursor. Better results were generally obtained with methallylsilane 1b than with 1a. This observation was rationalized by invoking the higher nucleophilicity of 1b and the faster β-fragmentation of the corresponding β-silyl radical intermediate. Calculation of the energy barrier for the β-fragmentation of a series of β-silyl radicals at the DFT level supported this hypothesis. Finally, a second version of these oximation and vinylation reactions, based on the utilization of 3-tris(trimethylsilyl)silylthiopropene, was devised, affording the desired oximes and olefins in reasonable yields. This strategy allowed the title reaction to be performed under milder conditions (AIBN, benzene, 80°C), as a result of the easier β-fragmentation of the C-S bond as compared with the C-Si bond.
Different radical initiation techniques of hydrosilylation reactions of multiple bonds in water: Dioxygen initiation
Postigo, Al,Nudelman, Norma Sbarbati
scheme or table, p. 910 - 914 (2011/09/15)
The relevance of radical initiation methodologies for the classical hydrosilylation reactions of organic compounds bearing C-C multiple bonds is due to the need to come up with newer and more efficient methods to effect this reaction, on account of its ap
Vinyl tris(trimethylsilyl)silanes: substrates for Hiyama coupling
Wang, Zhizhong,Pitteloud, Jean-Philippe,Montes, Lucresia,Rapp, Magdalena,Derane, Djenny,Wnuk, Stanislaw F.
, p. 5322 - 5327 (2008/09/21)
The oxidative treatment of vinyl tris(trimethylsilyl)silanes with hydrogen peroxide in aqueous sodium hydroxide in tetrahydrofuran generates reactive silanol or siloxane species that undergo Pd-catalyzed cross-couplings with aryl, heterocyclic, and alkenyl halides in the presence of Pd(PPh3)4 and tetrabutylammonium fluoride. Hydrogen peroxide and base are necessary for the coupling to occur while activation of the silanes with fluoride is not required. The conjugated and unconjugated tris(trimethylsilyl)silanes serve as good cross-coupling substrates. The (E)-silanes undergo coupling with retention of stereochemistry while coupling of (Z)-silanes occurred with lower stereoselectivity to produce an E/Z mixture of products.
Radical chain reactions using THP as a solvent
Yasuda, Hiroshi,Uenoyama, Yoshitaka,Nobuta, Osamu,Kobayashi, Shoji,Ryu, Ilhyong
, p. 367 - 370 (2008/09/17)
THP (tetrahydropyran) has been found to show an excellent stability towards autooxidation, compared with THF. Tributyltin hydride mediated radical cyclization, when conducted in THF as a solvent, suffers from competition of hydrogen abstraction from the solvent, whereas the use of THP resulted in the course to negligible degree. Tributyltin hydride, TTMSS, and hexanethiol mediated radical reactions were carried out successfully using THP as a solvent.
Radical reactions in aqueous medium using (Me3Si)3SiH
Postigo, Al,Kopsov, Sergey,Ferreri, Carla,Chatgilialoglu, Chryssostomos
, p. 5159 - 5162 (2008/09/17)
(Chemical Equation Presented) (Me3Si)3SiH was used as a successful reagent in a variety of radical-based transformations in water. The system comprising substrate, silane, and initiator (ACCN) mixed in aqueous medium at 100°C worked well for both hydrophilic and hydrophobic substrates, with the only variation that an amphiphilic thiol was also needed in case of the water-soluble compounds.
Radical-mediated silyl- and germyldesulfonylation of vinyl and (α-fluoro)vinyl sulfones: Application of tris(trimethylsilyl)silanes and tris(trimethylsilyl)germanes in Pd-catalyzed couplings
Wnuk, Stanislaw F.,Garcia Jr., Pedro I.,Wang, Zhizhong
, p. 2047 - 2049 (2007/10/03)
Equation presented. Radical-mediated silyl- and germyldesulfonylations of various vinyl and (α-fluoro)vinyl sulfones with tris(trimethylsilyl)silane and germanium hydrides provide access to vinyl and (α-fluoro)vinyl silanes and germanes. Upon oxidative treatment with hydrogen peroxide in basic aqueous solution, the vinyl tris(trimethylsilyl)silanes and -germanes undergo Pd-catalyzed cross-couplings with aryl halides.
