18849-30-4Relevant academic research and scientific papers
Synthesis and Structural Diversity of Triaryl(phenylethyl)silanes
Linnemannst?ns, Marvin,Mitzel, Norbert W.,Neumann, Beate,Stammler, Hans-Georg
, p. 1025 - 1034 (2020)
Starting from trichloro(phenylethyl)silane, six differently fluorinated triaryl(phenylethyl)silanes were synthesized by salt elimination reactions and their structures were determined by X-ray diffraction analysis. Tris(pentafluorophenyl)(phenylethyl)silane reveals a folded structure due to intramolecular π-stacking interactions, while those with a lower degree of fluorination show either intermolecular π-stacking or no interplay between the aryl groups. A similar folded structure was observed for (4-methylphenethyl)tris(pentafluorophenyl)silane and [2-(naphth-2-yl)ethyl]tris(pentafluorophenyl)silane, both generated from the corresponding trichlorosilanes. In contrast, the inversely fluorinated [2-(pentafluorophenyl)ethyl]triphenylsilane only revealed intermolecular π-stacking interactions. Compounds with tetrafluoropyridyl substituents behave differently; with these compounds, π-stacking is only observed between the fluorinated units. All compounds were analyzed by NMR and IR spectroscopy, elemental analyses and single-crystal X-ray diffraction, and found to have strong H/C/N/F···F and N···C contacts.
Rhodium-catalyzed anti-Markovnikov hydrosilylation of alkenes
Liu, Wei,Lu, Wenkui,Wu, Xiaoyu,Yang, Liqun,Zhang, Zhaoguo
supporting information, (2022/02/01)
Rh-catalyzed anti-Markovnikov hydrosilylation of terminal alkenes and tertiary silanes using readily-available PPh3 as the ligand was reported. This method facilitated the effective synthesis of alkylsilanes with a wide substrate scope and high
Visible-Light Decatungstate/Disulfide Dual Catalysis for the Hydro-Functionalization of Styrenes
Prieto, Alexis,Taillefer, Marc
supporting information, p. 1484 - 1488 (2021/03/08)
We describe an efficient photoredox system, relying on decatungstate/disulfide catalysts, for the hydrofunctionalization of styrenes. In this methodology the use of disulfide as a cocatalyst was shown to be crucial for the reaction efficiency. This photoredox system was employed for the hydro-carbamoylation, -acylation, -alkylation, and -silylation of styrenes, giving access to a large variety of useful building blocks and high-value molecules such as amides and unsymmetrical ketones from simple starting materials.
[Rh(Cod)Cl]2/Pph3?catalyzed dehydrogenative silylation of styrene derivatives with NBE as a hydrogen acceptor
Li, Chengyang,Lu, Wenkui,Wu, Xiaoyu,Xie, Xiaomin,Zhang, Zhaoguo
, p. 3780 - 3788 (2020/11/23)
Direct synthesis of arylalkenylsilanes by [Rh(COD)Cl]2/ PPh3-catalyzed dehydrogenative silylation of styrene derivatives with R3SiH (R = alkyl, alkoxy, aryl) was realized, in which norbornene (NBE) and PPh3 play a key role in achieving excellent selectivity in the formation of dehydrogenative silylation products. Moreover, this high-yielding transformation exhibits a broad substrate scope and good functional group tolerance.
Highly selective hydrosilylation of olefins and acetylenes by platinum(0) complexes bearing bulky N-heterocyclic carbene ligands
Zak,Bo?t,Kubicki,Pietraszuk
supporting information, p. 1903 - 1910 (2018/02/17)
Platinum complexes bearing bulky N-heterocyclic carbene (NHC) ligands, i.e., [Pt(IPr?)(dvtms)] (where, IPr? = 1,3-bis{2,6-bis(diphenylmethyl)-4-methylphenyl}imidazol-2-ylidene) and [Pt(IPr?OMe)(dvtms)] (where, IPr?OMe = 1,3-bis{2,6-bis(diphenylmethyl)-4-m
Well-defined NHC-rhodium hydroxide complexes as alkene hydrosilylation and dehydrogenative silylation catalysts
Truscott, Byron J.,Slawin, Alexandra M. Z.,Nolan, Steven P.
, p. 270 - 276 (2013/02/25)
Alkene hydrosilylation and dehydrogenative silylation reactions, mediated by [Rh(cod)(NHC)(OH)] complexes (cod = 1,5-cyclooctadiene; NHC = N-heterocyclic carbene) are described. The study details a comparison of the catalytic activity and steric characteristics of four rhodium complexes bearing different NHC ligands. The novel [Rh(cod)(Ii-PrMe)(OH)] complex (Ii-PrMe = 1,3-diisopropyl-4,5-dimethylimidazol-2-ylidine) was designed to improve the reactivity of Rh(i)-hydroxides and proved to be a successful promoter of hydrosilylation and dehydrogenative silylation, displaying good stereo- and regiocontrol. The Royal Society of Chemistry 2013.
Highly efficient B(C6F5)3-catalyzed hydrosilylation of olefins
Rubin, Michael,Schwier, Todd,Gevorgyan, Vladimir
, p. 1936 - 1940 (2007/10/03)
A convenient and highly efficient method for the Lewis acid-catalyzed trans-selective hydrosilylation of alkenes has been developed. The mechanism of this novel protocol operates via direct addition of silylium type species across C=C bond followed by trapping of the resultant carbenium ion with boron-bound hydride. A number of diversely substituted silanes possessing both aryl and alkyl groups at silicon atom were efficiently prepared using this hydrosilylation methodology. The possibility to employ aryl-containing hydrosilanes in this reaction opens broad capabilities for the synthesis of alcohols via a trans-selective hydrosilylation/Tamao - Fleming oxidation sequence, complementary to the existing cis-selective hydroboration/oxidation protocol.
Synthesis of alkenylsilanes via palladium(0)-catalyzed silylation of alkenyl iodides with hydrosilane
Murata, Miki,Watanabe, Shinji,Masuda, Yuzuru
, p. 9255 - 9257 (2007/10/03)
Various alkenyl iodides were silylated with hydrosilanes in the presence of KOAc and a catalytic amount of Pd2(dba)3·CHCl3 to afford the corresponding regio- and stereodefined (E)-alkenylsilanes in high yields.
Homogeneous catalytic hydrosilylation of the C=C double bond with platinum catalysts
Skoda-Foeldes, Rita,Kollar, Laszlo,Heil, Balint
, p. 275 - 280 (2007/10/02)
Hydrosilylation of vinyl- and vinylidene-type olefins (styrene (1a), 2-phenyl-propene (1b), methyl methacrylate (6)) has been carried out with either PtCl2 (dissolved in the substrate) or a platinum-phosphine catalyst prepared in situ.The activity and regioselectivity of the platinum-phosphine catalysts depend strongly on the phosphine structure and the metal/ligand ratio.Complexes involving chelating phosphines are inactive.Although mainly linear regioisomers are formed (2 and 7 respectively) in the reaction of 6, some 1,4-addition of the silane to the conjugated system also takes place to give a silyl ketene acetal derivative (8).A marked decrease in the reaction rate is observed if Ph3SiH instead of Et3SiH is used as the hydrosilylating agent.
HOMOGENEOUS CATALYSIS. IX. HYDROSILYLATION USING TRIS(PENTANEDIONATO)RHODIUM(III)-TRIALKYLALUMINIUM AS CATALYST
Cornish, Andrew J.,Lappert, Michael F.
, p. 153 - 168 (2007/10/02)
The two component (Ziegler) catalyst -AlEt3 (or an analogue with an alternative cocatalyst) has been investigated for the hydrosilylation by SiHX3 of alkynes, dienes, alkenes, styrene, or allylbenzene at 60 deg C.Terminal alkynes did not yield adducts, but internal alkynes RCCR' gave products of cis-addition with SiHEt3 or SiHEt2Me (but not SiH(OEt)3), without regiospecificity for the case of R R'.Acyclic dienes gave 1/1 adducts with SiHX3 (X = Me, Et, OEt or OSiMe3; but not X = Ph), predominantly (or, for penta-1,3-diene, exclusively) the products of 1,4-addition.Among cyclic dienes, only cyclohexa-1,3- (or -1,4)-diene was hydrosilylated with SiHEt3 to yield cyclohex-2-enyltriethylsilane; cycloocta-1,3-diene was merely rearranged to the 1,5-isomer, norbornadiene was polymerised, and no reaction was observed with 2,5-dimethylhexa-2,4-diene.Internal straight-chain alkenes RR'C=CHR'', RR'C=CR''R''', or cyclohexene proved unreactive; however disubstituted olefins RCH=CHR' gave the terminal (isomerised) 1/1-adducts, e.g., n-C5H11SiEt3 from MeCH=CHEt and SiHEt3.Likewise terminal alkenes RCH=CH2 gave RCH2CH2SiX3 (X = Ph or OEt) or (X = Et) a mixture of isomeric 1/1 adducts.With styrene and SiHEt3, or to a lesser extent SiH(OR)3 (R = Me or Et), the dehydrogenative hydrosilylated material, the vinylsilane PhCH=CHSiX3, was the principial product with isomeric 1/1 adduct byproducts; with allylbenzene, likewise, PhCH2CH=CHSiX3 was a significant, but less important, component of the reaction mixture.Mechanistic pathways are proposed; for the dehydrogenative hydrosilylation of styrene, crucial steps are styrene insertion into a RhIII-SiX3 bond and a subsequent intramolecular hydrogen transfer, which are consistent with both a labelling experiment using SiDEt3 and the lack of dehydrogenation (under the reaction conditions) of PhCH2CH2SiEt3.
