34074-18-5Relevant academic research and scientific papers
Tris(5,6,7,8-tetrafluoronaphthalen-2-yl)borane, a partially fluorinated boron lewis acid with fluorination distal to the boron atom
Mohr, Jens,Durmaz, Mustafa,Irran, Elisabeth,Oestreich, Martin
, p. 1108 - 1111 (2014)
Typical congeners of the boron Lewis acid tris(pentafluorophenyl)borane, B(C6F5)3, are fluorinated at the aryl groups directly attached to the boron atom. The chemistry of related electron-deficient boranes with fluorinati
Phosphirenium ions as masked phosphenium Catalysts: Mechanistic evaluation and application in synthesis
Gasperini, Danila,Neale, Samuel E.,Mahon, Mary F.,MacGregor, Stuart A.,Webster, Ruth L.
, p. 5452 - 5462 (2021/06/01)
The utilization of phosphirenium ions is presented; optimized and broadened three-membered ring construction is described together with the use of these ions as efficient pre-catalysts for metal-free carbonyl reduction with silanes. Full characterization of the phosphirenium ions is presented, and initial experimental and computational mechanistic studies indicate that these act as a "masked phosphenium"source that is accessed via ring opening. Catalysis proceeds via associative transfer of {Ph2P+} to a carbonyl nucleophile, Ha'SiR3 bond addition over the C=O group, and associative displacement of the product by a further equivalent of the carbonyl substrate, which completes the catalytic cycle. A competing off-cycle process leading to vinyl phosphine formation is detailed for the hydrosilylation of benzophenone for which an inverse order in [silane] is observed. Experimentally, the formation of side products, including off-cycle vinyl phosphine, is favored by electrondonating substituents on the phosphirenium cation, while catalytic hydrosilylation is promoted by electron-withdrawing substituents. These observations are rationalized in parallel computational studies.
Study of CoCu Alloy Nanoparticles Supported on MOF-Derived Carbon for Hydrosilylation of Ketones
Christensen, David B.,Mortensen, Rasmus L.,Kramer, S?ren,Kegn?s, S?ren
, p. 1537 - 1545 (2019/12/24)
Abstract: Carbonized zeolitic imidazolate frameworks (ZIFs) show potential as mesoporous heterogeneous catalysts with high metal loadings. ZIF-67 and ZIF-8 were used to create mono- and bimetallic CoCu particles supported on nitrogen-doped carbon via self
Re-Silane complexes as frustrated lewis pairs for catalytic hydrosilylation
Abrahamse, Michael,Brown, Caleb A.,Ison, Elon A.
supporting information, p. 11403 - 11411 (2020/09/02)
A pathway for the catalytic hydrosilylation of carbonyl substrates with M(C6F5)3 (M = B, Al and Ga) was calculated by DFT (B3PW91-D3) and it was shown that in the case of the Al reagent, the carbonyl substrate binds irreversibly and inhibits catalysis by
Cationic Ru-Se Complexes for Cooperative Si-H Bond Activation
Irran, Elisabeth,Klare, Hendrik F. T.,Oberling, Marvin,Oestreich, Martin,Ohki, Yasuhiro
supporting information, p. 4747 - 4753 (2020/12/22)
The preparation and structural characterization of mononuclear tethered ruthenium(II) complexes of type [(DmpSe)Ru(PR3)]+BArF4- (DmpSe = 2,6-dimesitylphenyl selenolate, ArF = 3,5-bis(trifluoromethyl)phenyl) are described. Unlike relevant known selenolate
Air- and water-stable Lewis acids: Synthesis and reactivity of P-trifluoromethyl electrophilic phosphonium cations
Fasano,LaFortune,Bayne,Ingleson,Stephan
supporting information, p. 662 - 665 (2018/02/06)
A new class of electrophilic phosphonium cations (EPCs) containing a -CF3 group attached to the phosphorus(v) center is readily accessible in high yields, via a scalable process. These species are stable to air, water, alcohol and strong Br?nsted acid, even at raised temperatures. Thus, P-CF3 EPCs are more robust than previously reported EPCs containing P-X moieties (X = F, Cl, OR), and despite their reduced Lewis acidity they function as Lewis acid catalysts without requiring anhydrous reaction conditions.
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.
Rhodium-Catalyzed Dehydrogenative Silylation of Acetophenone Derivatives: Formation of Silyl Enol Ethers versus Silyl Ethers
Garcés, Karin,Lalrempuia, Ralte,Polo, Víctor,Fernández-Alvarez, Francisco J.,García-Ordu?a, Pilar,Lahoz, Fernando J.,Pérez-Torrente, Jesús J.,Oro, Luis A.
, p. 14717 - 14729 (2016/10/03)
A series of rhodium–NSiN complexes (NSiN=bis (pyridine-2-yloxy)methylsilyl fac-coordinated) is reported, including the solid-state structures of [Rh(H)(Cl)(NSiN)(PCy3)] (Cy=cyclohexane) and [Rh(H)(CF3SO3)(NSiN)(coe)] (coe=cis-cyclooctene). The [Rh(H)(CF3SO3)(NSiN)(coe)]-catalyzed reaction of acetophenone with silanes performed in an open system was studied. Interestingly, in most of the cases the formation of the corresponding silyl enol ether as major reaction product was observed. However, when the catalytic reactions were performed in closed systems, formation of the corresponding silyl ether was favored. Moreover, theoretical calculations on the reaction of [Rh(H)(CF3SO3)(NSiN)(coe)] with HSiMe3and acetophenone showed that formation of the silyl enol ether is kinetically favored, while the silyl ether is the thermodynamic product. The dehydrogenative silylation entails heterolytic cleavage of the Si?H bond by a metal–ligand cooperative mechanism as the rate-determining step. Silyl transfer from a coordinated trimethylsilyltriflate molecule to the acetophenone followed by proton transfer from the activated acetophenone to the hydride ligand results in the formation of H2and the corresponding silyl enol ether.
Efficient hydrosilylation of carbonyl compounds by 1,1,3,3-tetramethyldisiloxane catalyzed by Au/TiO2
Vasilikogiannaki, Eleni,Titilas, Ioannis,Gryparis, Charis,Louka, Anastasia,Lykakis, Ioannis N.,Stratakis, Manolis
, p. 6106 - 6113 (2014/12/10)
1,1,3,3-Tetramethyldisiloxane (TMDS) is a highly reactive reducing reagent in the Au/TiO2-catalyzed hydrosilylation of carbonyl compounds relative to monohydrosilanes. The reduction of aldehydes or ketones with TMDS can be performed on many occasions at ambient conditions within short reaction times and at low loading levels of gold, whereas typical monohydrosilanes require excess heating and prolonged time for completion. The product yields are excellent, while almost stoichiometric amounts of carbonyl compounds and TMDS can be used. It is postulated that the enhanced reactivity of TMDS is attributed to the formation of a gold dihydride intermediate. This intermediate is also supported by the fact that double hydrosilylation of carbonyl compounds by TMDS is a negligible pathway.
Efficient hydrosilylation of carbonyl compounds by 1,1,3,3-tetramethyldisiloxane catalyzed by Au/TiO2
Vasilikogiannaki, Eleni,Titilas, Ioannis,Gryparis, Charis,Louka, Anastasia,Lykakis, Ioannis N.,Stratakis, Manolis
, p. 6106 - 6113 (2015/03/30)
1,1,3,3-Tetramethyldisiloxane (TMDS) is a highly reactive reducing reagent in the Au/TiO2-catalyzed hydrosilylation of carbonyl compounds relative to monohydrosilanes. The reduction of aldehydes or ketones with TMDS can be performed on many occ
