3429-76-3Relevant articles and documents
On the mechanism of the naphthalene-catalysed lithiation: The role of the naphthalene dianion
Yus, Miguel,Herrera, Raquel P,Guijarro, Albert
, p. 3455 - 3458 (2001)
Kinetic and distribution product studies on naphthalene-catalysed lithiation reactions of chlorinated precursors have shown the probable participation of a naphthalene dianion (dilithium naphthalene) as the very active electron carrier agent in the chlorine-lithium exchange process.
PROCESS FOR FUNCTIONALIZATION OF ORGANO-METAL COMPOUNDS WITH SILYL-BASED FUNCTIONALIZATION AGENTS AND SILYL-FUNCTIONALIZED COMPOUNDS PREPARED THEREBY
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Paragraph 0085; 0086, (2019/10/15)
A process to functionalized organo-metal compounds with silyl-based electrophiles. The process includes combining an organo-metal compound, a silyl-based functionalization agent, and an optional solvent. Functionalized silanes and silyl-terminated polyolefins can be prepared by this process.
Hydrosilane synthesis via catalytic hydrogenolysis of halosilanes using a metal-ligand bifunctional iridium catalyst
Beppu, Teruo,Sakamoto, Kei,Nakajima, Yumiko,Matsumoto, Kazuhiro,Sato, Kazuhiko,Shimada, Shigeru
, p. 75 - 80 (2018/06/20)
Hydrogenolysis of various halosilanes was catalysed by iridium amido complexes to produce hydrosilanes. Selective monohydrogenolysis of di- and trichlorosilanes similarly proceeded, resulting in the formation of chlorohydrosilanes (R2SiHCl or RSiHCl2) as synthetically important building blocks for various organosilicon compounds. A mechanistic study supported the in-situ formation of an iridium hydride species as a key intermediate, which could transfer the hydride to the silicon atom through a metal–ligand bifunctional mechanism. One-pot hydrotrimethylsilylation of olefins was achieved via successive hydrogenolysis and hydrosilylation reactions starting from Me3SiCl.
Utilization of a Trimethylsilyl Group as a Synthetic Equivalent of a Hydroxyl Group via Chemoselective C(sp3)-H Borylation at the Methyl Group on Silicon
Torigoe, Takeru,Ohmura, Toshimichi,Suginome, Michinori
, p. 2943 - 2956 (2017/03/23)
A conversion of trimethylsilylalkanes into the corresponding alcohols is established based on an iridium-catalyzed, chemoselective C(sp3)-H borylation of the methyl group on silicon. The (borylmethyl)silyl group formed by C(sp3)-H borylation is treated with H2O2/NaOH, and the resulting (hydroxymethyl)silyl group is converted into a hydroxyl group by Brook rearrangement, followed by oxidation of the resulting methoxysilyl group under Tamao conditions. An alternative route proceeding through the formylsilyl group formed from a (hydroxymethyl)silyl group by Swern oxidation is also established. The method is applicable to substituted trimethylsilylcycloalkanes and 1,1-dimethyl-1-silacyclopentane for conversion into the corresponding stereodefined cycloalkyl alcohols and 1,4-butanediol.
Cyclohexa-1,3-diene-based dihydrogen and hydrosilane surrogates in B(C6F5)3-catalysed transfer processes
Yuan, Weiming,Orecchia, Patrizio,Oestreich, Martin
supporting information, p. 10390 - 10393 (2017/09/25)
The cyclohexa-1,3-diene motif is introduced as an equally effective alternative to the cyclohexa-1,4-diene platform in B(C6F5)3-catalysed transfer processes. The transfer hydrogenation of alkenes is realised with α-terpinene and the related transfer hydrosilylation is achieved with 5-trimethylsilyl-substituted cyclohexa-1,3-diene. Both yields and substrate scope are comparable with the prior systems.
Use of cyclohexa-2,5-dien-1-yl-silanes as precursors for gaseous hydrosilanes
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Paragraph 0034; 0035; 0037, (2015/03/18)
The invention relates to the use of cyclohexa-2,5-dien-1-yl-silanes of general formula I for generation of hydrosilanes in solution using a strong Lewis acid. This way, e.g., alkenes can be hydrosilylated in good yields using the cyclohexa-2,5-dien-1-yl-silanes of general formula I as transfer hydrosilylating agents in the presence of a strong Lewis acid as catalyst with concomitant formation of an arene solvent.
USE OF CYCLOHEXA-2,5-DIEN-1-YL-SILANES AS PRECURSORS FOR GASEOUS HYDROSILANES
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Page/Page column 11; 12, (2015/03/28)
The invention relates to the use of cyclohexa-2,5-dien-1 -yl-silanes of general formula (I), for generation of hydrosilanes in solution using a strong Lewis acid. This way, e.g., alkenes or carbonyl compounds can be hydrosilylated in good yields using the cyclohexa-2,5-dien-1 - yl-silanes of general formula I as transfer hydros! lylating agents in the presence of a strong Lewis acid as catalyst with concomitant formation of an arene solvent.
3-silylated cyclohexa-1,4-dienes as precursors for gaseous hydrosilanes: The B(C6F5)3-catalyzed transfer hydrosilylation of alkenes
Simonneau, Antoine,Oestreich, Martin
supporting information, p. 11905 - 11907 (2013/11/19)
Set Me3SiH free! The strong Lewis acid B(C6F 5)3 catalyzes the release of hydrosilanes from 3-silylated cyclohexa-1,4-dienes with concomitant formation of benzene. Subsequent B(C 6F5)3
Aliphatic organolithiums by fluorine-lithium exchange: n-octyllithium
Yus, Miguel,Herrera, Raquel P.,Guijarro, Albert
, p. 5025 - 5027 (2007/10/03)
The reaction of 1-fluorooctane (1) with an excess of lithium powder (4-10 equiv.) and DTBB (2-4 equiv.) in THP at 0°C for 5 min gives a solution of the corresponding 1-octyllithium (2), which reacts then with different electrophiles at 0°C (D2O, MeSiCl, ButCHO, Et2CO), or -78°C [ClCO2Me, (PhCH2S)2] or -40°C (CO2) to room temperature to give, after hydrolysis, the expected products (3). The same process applied to 2-fluorooctane gives mainly octane as reaction product, independently on the electrophile used, resulting from a proton abstraction by 2-lithiooctane formed from the reaction medium before addition of the electrophilic reagent.
On the mechanism of arene-catalyzed lithiation: The role of arene dianions - Naphthalene radical anion versus naphthalene dianion
Yus, Miguel,Herrera, Raquel P.,Guijarro, Albert
, p. 2574 - 2584 (2007/10/03)
The use of lithium and a catalytic amount of an arene is a well-established methodology for the preparation of organolithium reagents that manifest greater reactivity than the classical lithium-arene solutions. In order to rationalize this conduct, the participation of a highly reduced species, the dianion, is proposed and its reactivity explored. Studies of kinetics and of distribution of products reveal that the electron-transfer (ET) reactivity profile of dilithium naphthalenide in its reaction with organic chlorides excludes alternative mechanisms of halogen- lithium exchange. The process generates organolithium compounds. The dianion thus emerges along with the radical anion as a suitable candidate for catalytic cycles in certain processes. Endowed with a higher redox potential than its radical anion counterpart, dilithium naphthalene displays a broader spectrum of reactivity and so increases the range of substrates suitable for lithiation. The reaction of dilithium naphthalene with THF is one example of the divergent reactivity of the radical anion and the dianion, which has been the source of apparent misinterpretation of results in the past and has now been appropriately addressed.
