17915-17-2Relevant academic research and scientific papers
Mild synthesis of silyl ethers: Via potassium carbonate catalyzed reactions between alcohols and hydrosilanes
Delucia, Nicholas A.,Das, Nivedita,Vannucci, Aaron K.
, p. 3415 - 3418 (2018/05/23)
A method has been developed for the silanolysis of alcohols using an abundant and non-corrosive base K2CO3 as a catalyst. Reactions between a variety of alcohols and hydrosilanes generate silyl ethers under mild conditions. The use of hydrosilanes leads to the formation of H2 as the only byproduct thus avoiding the formation of stoichiometric strong acids. The mild conditions lead to a wide scope of possible alcohol substrates and good functional group tolerance. Selective alcohol silanolysis is also observed in the presence of reactive C-H bonds, lending this method for extensive use in protection group chemistry.
HYDROXIDE-CATALYZED FORMATION OF SILICON-OXYGEN BONDS BY DEHYDROGENATIVE COUPLING OF HYDROSILANES AND ALCOHOLS
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Paragraph 0148; 0176, (2017/02/28)
The present disclosure is directed to methods for dehydrogenatively coupled hydrosilanes and alcohols, the methods comprising contacting an organic substrate having at least one organic alcohol moiety with a mixture of at least one hydrosilane and sodium and/or potassium hydroxide, the contacting resulting in the formation of a dehydrogenatively coupled silyl ether. The disclosure further described associated compositions and methods of using the formed products.
N-Methyl-Benzothiazolium Salts as Carbon Lewis Acids for Si?H σ-Bond Activation and Catalytic (De)hydrosilylation
Fasano, Valerio,Radcliffe, James E.,Curless, Liam D.,Ingleson, Michael J.
supporting information, p. 187 - 193 (2017/01/09)
N?Me-Benzothiazolium salts are introduced as a new family of Lewis acids able to activate Si?H σ bonds. These carbon-centred Lewis acids were demonstrated to have comparable Lewis acidity towards hydride as found for the triarylboranes widely used in Si?H σ-bond activation. However, they display low Lewis acidity towards hard Lewis bases such as Et3PO and H2O in contrast to triarylboranes. The N?Me-benzothiazolium salts are effective catalysts for a range of hydrosilylation and dehydrosilylation reactions. Judicious selection of the C2 aryl substituent in these cations enables tuning of the steric and electronic environment around the electrophilic centre to generate more active catalysts. Finally, related benzoxazolium and benzimidazolium salts were found also to be active for Si?H bond activation and as catalysts for the hydrosilylation of imines.
One-step chemoselective conversion of tetrahydropyranyl ethers to silyl-protected alcohols
Bergueiro, Julian,Montenegro, Javier,Saa, Carlos,Lopez, Susana
, p. 14475 - 14479 (2014/04/17)
Aluminium trichloride catalyses the expeditious direct conversion of tetrahydropyranyl ethers to silyl ethers. This one-step transformation is chemoselective versus deprotection of the acetal and hydrosilylation of unsaturated carbon-carbon bonds, and can also be applied to linear acetals. A possible mechanism is tentatively proposed. This journal is the Partner Organisations 2014.
N-Methylacridinium Salts: Carbon Lewis Acids in Frustrated Lewis Pairs for σ-Bond Activation and Catalytic Reductions
Clark, Ewan R.,Ingleson, Michael J.
supporting information, p. 11306 - 11309 (2016/02/19)
N-methylacridinium salts are Lewis acids with high hydride ion affinity but low oxophilicity. The cation forms a Lewis adduct with 4-(N,N-dimethylamino)pyridine but a frustrated Lewis pair (FLP) with the weaker base 2,6-lutidine which activates H2, even in the presence of H2O. Anion effects dominate reactivity, with both solubility and rate of H2 cleavage showing marked anion dependency. With the optimal anion, a N-methylacridinium salt catalyzes the reductive transfer hydrogenation and hydrosilylation of aldimines through amine-boranes and silanes, respectively. Furthermore, the same salt is active for the catalytic dehydrosilylation of alcohols (primary, secondary, tertiary, and ArOH) by silanes with no observable over-reduction to the alkanes.
N-heterocyclic carbene organocatalysts for dehydrogenative coupling of silanes and hydroxyl compounds
Gao, Dongjing,Cui, Chunming
supporting information, p. 11143 - 11147 (2013/09/02)
Go organic! N-Heterocyclic carbene (NHC) 1,3-diisopropyl-4,5- dimethylimidazol-2-ylidene (IiPr) has been found to be an efficient and selective catalyst for the dehydrogenative coupling of a wide range of silanes and hydroxyl groups to form Si-O bonds under mild and solvent-free conditions (see scheme). Mechanistic studies indicated that the activation of hydroxyl groups by the NHC is the most plausible initial step for the process. Copyright
Using the nonaqueous electrolytic solution and secondary battery
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, (2007/10/12)
PROBLEM TO BE SOLVED: To provide nonaqueous electrolyte solution capable of improving at least either large-current charge/discharge characteristics or charge/discharge capacity, and a nonaqueous electrolyte solution secondary battery using it. SOLUTION: Electrolyte solution that is liquid electrolyte is immersed in a separator 23. The electrolyte solution contains a liquid solvent, for instance, a nonaqueous solvent such as an organic solvent, and electrolyte salt dissolved in the nonaqueous solvent. Further, as additives, it contains at least one type selected from tris (penta-fluorophenyl) borane (TPFPB) and tris-borate (2H-hexafluoro isopropyl) (THFPB), and at least one type selected from vinylene carbonate (VC) and vinyl ethylene carbonate (VEC). COPYRIGHT: (C)2008,JPO&INPIT
Cationic silane δ-complexes of ruthenium with relevance to catalysis
Gutsulyak, Dmitry V.,Vyboishchikov, Sergei F.,Nikonov, Georgii I.
supporting information; experimental part, p. 5950 - 5951 (2010/07/05)
Hydrosilylation of carbonyls catalyzed by 2 goes via intermediate formation of cationic silane σ-complexes 4 which undergo nucleophilic abstraction of the silylium cation studied by DFT calculations.
An Efficient Catalyst for the Conversion of Hydrosilanes to Alkoxysilanes
Lorenz, Catrin,Schubert, Ulrich
, p. 1267 - 1270 (2007/10/03)
The copper(I) hydride 6 is an efficient catalyst for the alcoholysis of primary and secondary silanes.The reactions proceed at room temperature within a few hours and give the alkoxysilanes in high yields.Only with bulky alcohols or silanes are longer reaction times and/or increased temperatures required.The presence of air accelarates the reactions and gives rise to higher yields of alkoxysilanes, particularly with bulky alcohols.Diols react with PhRSiH2 (R = Me, Ph) to afford 1,3-dioxo-2-silacycloalkanes and with tertiary silanes to furnish the bissilylated diols.When unsaturated alcohols (2-propen-1-ol or 2-propyn-1-ol) are employed, the double or triple bond is retained. - Keywords: Catalytic silane alcoholysis; Alkoxysilanes
Conversion of hydrosilanes to alkoxysilanes catalyzed by Cp2TiCl2/nBuLi
Bedard, Thomas C.,Corey, Joyce Y.
, p. 315 - 333 (2007/10/02)
The combination of Cp2TiCl2 and nBuLi provides an effective catalyst for alcoholysis of the model silanes n-HexSiH3, PhMeSiH2, Ph2SiH2 and PhMe2SiH by ethanol, isopropanol, t-butyl alcohol and phenol.Increasing the steric bulk of the substituents on either the alcohol or the silane generally requires longer reaction periods and/or increasing temperature.All SiH bonds are converted to SiOEt groups by ethanol and a single SiH bond in secondary silanes and two SiH bonds in tertiary silanes are replaced by t-butyl alcohol.Diols including pinacol, 2,4-pentanediol and 2,5-hexanediol react with PhRSiH2 (R = Me, Ph) to give 1,3-dioxa-2-silacyclopentanes, -hexanes and -heptanes, respectively.Attempts to form caged structures by condensation of primary silanes and triols was unsuccessful.Hydrolysis of PhRSiH2 is promoted by Cp2TiCl2/n-BuLi and the siloxane is produced in quantitative yield when R = Ph and a mixture of linear disiloxanes and trisiloxanes in addition to cyclopolysilanes are produced when R = Me.Other protic reagents including acids, mercaptans, amines and enolizable ketones did not react.The effects of reaction parameters such as temperature, silane to catalyst ratio, solvent, transition metal and replacements for nBuLi were also determined.
