- Mechanistic study of alkene hydrosilylation catalyzed by a β-dialdiminate cobalt(i) complex
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Alkene hydrosilylation is a large-scale process that typically uses precious-metal catalysts. A new generation of highly selective catalysts is based on inexpensive metals, which may have a high-spin electronic configuration and thus may follow novel mech
- Chen, Chi,Holland, Patrick L.,Kim, Daniel,Mercado, Brandon Q.,Weix, Daniel J.
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Read Online
- Geometrically Constrained Cationic Low-Coordinate Tetrylenes: Highly Lewis Acidic σ-Donor Ligands in Catalytic Systems
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A novel non-innocent ligand class, namely cationic single-centre ambiphiles, is reported in the phosphine-functionalised cationic tetrylene Ni0 complexes, [PhRDippENi(PPh3)3]+ (4 a/b (Ge) and 5 (Sn); PhRDipp={[Ph2PCH2SiR2](Dipp)N}?; R=Ph, iPr; Dipp=2,6-iPr2C6H3). The inherent electronic nature of low-coordinate tetryliumylidenes, combined with the geometrically constrained [N?E?Ni] bending angle enforced by the chelating phosphine arm in these complexes, leads to strongly electrophilic EII centres which readily bind nucleophiles, reversibly in the case of NH3. Further, the GeII centre in 4 a/b readily abstracts the fluoride ion from [SbF6]? to form the fluoro-germylene complex PhRDippGe(F)Ni(PPh3)3 9, despite this GeII centre simultaneously being a σ-donating ligand towards Ni0. Alongside the observed catalytic ability of 4 and 5 in the hydrosilylation of alkynes and alkenes, this forms an exciting introduction to a multi-talented ligand class in cationic single-centre ambiphiles.
- Keil, Philip M.,Hadlington, Terrance J.
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supporting information
(2022/01/13)
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- Nickel-Catalyzed Hydrosilylation of Terminal Alkenes with Primary Silanes via Electrophilic Silicon-Hydrogen Bond Activation
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We report a simple and effective nickel-based catalytic system, NiCl2·6H2O/tBuOK, for the electrophilically activated hydrosilylation of terminal alkenes with primary silanes. This protocol provides excellent performance under mild reaction conditions: ex
- Wu, Xiaoyu,Ding, Guangni,Lu, Wenkui,Yang, Liqun,Wang, Jingyang,Zhang, Yuxuan,Xie, Xiaomin,Zhang, Zhaoguo
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supporting information
p. 1434 - 1439
(2021/02/16)
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- Thermally Stable Rare-Earth Metal Complexes Supported by Chelating Silylene Ligands
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The use of N-heterocyclic silylenes (NHSi) as ligands is a rapidly developing field. However, only a handful of f-element silylene complexes have been disclosed so far. Herein, we report the synthesis and characterization of a series of thermally stable d
- Kraetschmer, Frederic,Roesky, Peter W.,Simler, Thomas,Sun, Xiaofei
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p. 2100 - 2107
(2021/07/20)
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- Method of manufacturing organic silicon compound (by machine translation)
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[Problem] to efficiently producing method of an organic silicon compound. The hydrosilane compounds in the presence of the catalyst in a reaction step [a] an alkene containing an organic silicon compound which, in the reaction process, the catalyst used is iron complex compound represented by the formula. R1 And R2 C each independently1 - C6 The hydrocarbon group, which may have a substituent C1 - C12 The aromatic hydrocarbon group, or a halogen atom, R3 C each independently1 - C12 Alkyl group, or a substituent which may be C6 - C12 The aromatic hydrocarbon group, X is independently a halogen atom, C1 - C12 Alkoxy, - OC (O) R6 (R6 C is1 - C12 The hydrocarbon group), or a trialkylsilyl group which may have a C1 - C12 Hydrocarbon group, is an integer of 0 - 4 n1, is an integer of 0 - 5 n2. [Drawing] no (by machine translation)
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Paragraph 0059-0061
(2020/05/07)
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- Bench-Stable Cobalt Pre-Catalysts for Mild Hydrosilative Reduction of Tertiary Amides to Amines and Beyond
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The readily synthesized and bench-stable cobalt dichloride complex (dpephos)CoCl2 is employed as a pre-catalyst for a diversity of silane additions to unsaturated organic molecules, including the normally challenging reduction of amides to amines. With regard to hydrosilative reduction of amides even more effective and activator free catalytic systems can be generated from the bench-stable, commercially available Co(acac)2 and Co(OAc)2 with dpephos and PPh3 ligands. These systems operate under mild conditions (100 °C), with many examples of room temperature transformations, presenting a first example of mild cobalt-catalyzed hydrosilylation of amides.
- Nurseiit, Alibek,Janabel, Jaysan,Gudun, Kristina A.,Kassymbek, Aishabibi,Segizbayev, Medet,Seilkhanov, Tulegen M.,Khalimon, Andrey Y.
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p. 790 - 798
(2019/01/09)
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- Magnesium hydride alkene insertion and catalytic hydrosilylation
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The dimeric β-diketiminato magnesium hydride, [(BDI)MgH]2, reacts at 80 °C with the terminal alkenes, 1-hexene, 1-octene, 3-phenyl-1-propene and 3,3-dimethyl-butene to provide the respective n-hexyl, n-octyl, 3-phenylpropyl and 3,3-dimethyl-but
- Garcia, Lucia,Dinoi, Chiara,Mahon, Mary F.,Maron, Laurent,Hill, Michael S.
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p. 8108 - 8118
(2019/09/19)
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- Multimetallic Alkaline-Earth Hydride Cations
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Reactions of dimeric β-diketiminato (BDI) magnesium and calcium hydrides with [(BDI)Mg]+[Al{OC(CF3)3}4]- provide ionic multimetallic hydride derivatives, which have been characterized by single-crysta
- Garcia, Lucia,Mahon, Mary F.,Hill, Michael S.
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p. 3778 - 3785
(2019/11/13)
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- Preparation method and application of 2, 9-diaryl-substituted phenanthroline and 2, 9-diaryl-substituted phenanthroline iron complex
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The present invention relates to a preparation method and application of 2, 9-diaryl-substituted phenanthroline and a 2, 9-diaryl-substituted phenanthroline iron complex. Specifically, the substitutedphenanthroline is prepared by Suzuki coupling reaction
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Paragraph 0142; 0143; 0144; 0145; 0146; 0147; 0148; 0149
(2018/04/02)
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- A β-diketiminate manganese catalyst for alkene hydrosilylation: Substrate scope, silicone preparation, and mechanistic insight
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The dimeric β-diketiminate manganese hydride compound, [(2,6-iPr2PhBDI)Mn(μ-H)]2, was prepared by treating [(2,6-iPr2PhBDI)Mn(μ-Cl)]2 with NaEt3BH. This compound was characterized by single crystal X-
- Mukhopadhyay, Tufan K.,Flores, Marco,Groy, Thomas L.,Trovitch, Ryan J.
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p. 7673 - 7680
(2018/10/24)
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- Synthesis of divalent ytterbium terphenylamide and catalytic application for regioselective hydrosilylation of alkenes
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The dimeric heteroleptic ytterbium amido complex [(2,6-(3,5-Me2C6H3)2C6H3NH)Yb(N(SiMe3)2)]2 (1) has been prepared and characterized. This divalent terphenyl
- Shi, Yinghua,Li, Jianfeng,Cui, Chunming
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p. 10957 - 10962
(2017/09/01)
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- Cobalt-Catalyzed Regiodivergent Hydrosilylation of Vinylarenes and Aliphatic Alkenes: Ligand- and Silane-Dependent Regioselectivities
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We report a regiodivergent hydrosilylation of alkenes catalyzed by catalysts generated in situ from bench-stable Co(acac)2 and phosphine- or nitrogen-based ligands. A wide range of vinylarenes and aliphatic alkenes reacted to afford either branched (45 examples) or linear (37 examples) organosilanes in high isolated yields (average: 84%) and high regioselectivities (from 91:9 to >99:1). This transformation tolerates a variety of functional groups including ether, silyloxy, thioether, epoxide, halogen, amine, ester, boronic ester, acetal, cyano, and ketone moieties. Mechanistic studies suggested that the hydrosilylation of alkenes catalyzed by the cobalt/bisphosphine system follows the Chalk-Harrod mechanism (with a Co-H intermediate), and the hydrosilylation of alkenes catalyzed by the cobalt/pyridine-2,6-diimine system follows the modified Chalk-Harrod mechanism (with a Co-Si intermediate). Systematic studies with sterically varied silanes revealed that the steric properties of silanes play a pivotal role in controlling the regioselectivity of vinylarene hydrosilylation and the chemoselectivity of the reactions of aliphatic alkenes and silanes catalyzed by the cobalt/pyridine-2,6-diimine system.
- Wang, Chao,Teo, Wei Jie,Ge, Shaozhong
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p. 855 - 863
(2017/06/07)
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- Efficient and selective catalysis for hydrogenation and hydrosilation of alkenes and alkynes with PNP complexes of scandium and yttrium
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Scandium and yttrium congeneric complexes, supported by a monoanionic PNP ligand, were studied as catalysts for alkene hydrogenation and hydrosilation, and alkyne semihydrogenation and semihydrosilation. The yttrium congener was found to be much more acti
- Levine, Daniel S.,Tilley, T. Don,Andersen, Richard A.
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supporting information
p. 11881 - 11884
(2017/11/06)
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- Variable coordination geometries: Via an amine-tethered-enamidophosphinimine ligand on cobalt
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The synthesis of two new amine-tethered enamidophosphinimine donor sets is described and their coordination chemistry with cobalt(ii) detailed. Deprotonation of the enamine tautomers of each system generates the lithium derivatives that are used in metath
- Suzuki, Tatsuya,Masuda, Hideki,Fryzuk, Michael D.
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p. 6612 - 6622
(2017/07/10)
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- Activation of Ene-Diamido Samarium Methoxide with Hydrosilane for Selectively Catalytic Hydrosilylation of Alkenes and Polymerization of Styrene: An Experimental and Theoretical Mechanistic Study
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Samarium methoxide incorporating the ene-diamido ligand L(DME)Sm(μ-OMe)2Sm(DME)L (1; L = [DipNC(Me)C(Me)NDip]2-, Dip = 2,6-iPr2C6H3, and DME = 1,2-dimethoxyethane) has been prepared and structurally c
- Li, Jianfeng,Zhao, Chaoyue,Liu, Jinxi,Huang, Hanmin,Wang, Fengxin,Xu, Xiufang,Cui, Chunming
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p. 9105 - 9111
(2016/11/15)
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- Aryl-substituted BIAN complexes of iron dibromide: Synthesis, X-ray and electronic structure, and catalytic hydrosilylation activity
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Anhydrous iron dibromide complexes bearing bidentate α-diimine ligands ArN=C(Me)-(Me)C=NAr and ArBIAN (BIAN = bis(imino)acenaphthene; Ar = dpp and Mes; dpp = 2,6-diisopropylphenyl; Mes = 2,4,6-trimethylphenyl) have been pr
- Supej, Michael J.,Volkov, Alexander,Darko, Louisa,West, Ryan A.,Darmon, Jonathan M.,Schulz, Charles E.,Wheeler, Kraig A.,Hoyt, Helen M.
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p. 403 - 414
(2016/07/06)
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- Rapid, Regioconvergent, Solvent-Free Alkene Hydrosilylation with a Cobalt Catalyst
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Alkene hydrosilylation is typically performed with Pt catalysts, but inexpensive base-metal catalysts would be preferred. We report a Co catalyst for anti-Markovnikov alkene hydrosilylation that can be used without added solvent at low temperatures with l
- Chen, Chi,Hecht, Maxwell B.,Kavara, Aydin,Brennessel, William W.,Mercado, Brandon Q.,Weix, Daniel J.,Holland, Patrick L.
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supporting information
p. 13244 - 13247
(2015/11/09)
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- Titanium and zirconium complexes of the N,N′-bis(2,6-diisopropylphenyl)-1,4-diaza-butadiene ligand: Syntheses, structures and uses in catalytic hydrosilylation reactions
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We report here a number of dianionic 1,4-diaza-1,3-butadiene complexes of titanium and zirconium synthesised by a salt metathesis reaction. The reaction of either CpTiCl3 or Cp2TiCl2 with the dilithium salt of N,N′-bis(2,6
- Anga, Srinivas,Naktode, Kishor,Adimulam, Harinath,Panda, Tarun K.
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supporting information
p. 14876 - 14888
(2015/02/19)
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- Structural and mechanistic investigation of a cationic hydrogen-substituted ruthenium silylene catalyst for alkene hydrosilation
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The cationic ruthenium silylene complex [Cp*(iPr 3P)Ru(H)2(SiHMes)][CB11H6Br 6], a catalyst for olefin hydrosilations with primary silanes, was isolated and characterized by X-ray crystallography. Relatively strong interactions between the silylene Si atom and Ru-H hydride ligands appear to reflect a highly electrophilic silicon center. The mechanism of olefin hydrosilation was examined by kinetics measurements and other experiments to provide the first experimentally determined mechanism for the catalytic cycle. This mechanism involves a fast, initial addition of the Si-H bond of the silylene complex to the olefin. Subsequent elimination of the product silane produces an unsaturated intermediate, which can be reversibly trapped by olefin or intercepted by the silane substrate. The latter reaction pathway involves activation of the reactant silane by Si-H oxidative addition and α-hydrogen migration to regenerate the key silylene intermediate.
- Fasulo, Meg E.,Lipke, Mark C.,Tilley, T. Don
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p. 3882 - 3887
(2013/09/23)
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- Catalytic hydrosilylation of alkenes by iron complexes containing terpyridine derivatives as ancillary ligands
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Iron complexes formulated as Fe(terpy)X2 (terpy = 2,2′:6′,2 -terpyridine derivatives; X = Cl, Br) were prepared and their catalytic activities for hydrosilylation of olefin with hydrosilane were examined. Although Fe(terpy)X2 did not
- Kamata, Kouji,Suzuki, Atsuko,Nakai, Yuta,Nakazawa, Hiroshi
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scheme or table
p. 3825 - 3828
(2012/07/02)
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- Iron-copper cooperative catalysis in the reactions of alkyl grignard reagents: Exchange reaction with alkenes and carbometalation of alkynes
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Iron-copper cooperative catalysis is shown to be effective for an alkene-Grignard exchange reaction and alkylmagnesiation of alkynes. The Grignard exchange between terminal alkenes (RCH=CH2) and cyclopentylmagnesium bromide was catalyzed by FeCl3 (2.5 mol %) and CuBr (5 mol %) in combination with PBu3 (10 mol %) to give RCH2CH 2MgBr in high yields. 1-Alkyl Grignard reagents add to alkynes in the presence of a catalyst system consisting of Fe(acac)3, CuBr, PBu3, and N,N,N″,N″-tetramethylethylenediamine to give β-alkylvinyl Grignard reagents. The exchange reaction and carbometalation take place on iron, whereas copper assists with the exchange of organic groups between organoiron and organomagnesium species through transmetalation with these species. Sequential reactions consisting of the alkene-Grignard exchange and the alkylmagnesiation of alkynes were successfully conducted by adding an alkyne to a mixture of the first reaction. Isomerization of Grignard reagents from 2-alkyl to 1-alkyl catalyzed by Fe-Cu also is applicable as the first 1-alkyl Grignard formation step.
- Shirakawa, Eiji,Ikeda, Daiji,Masui, Seiji,Yoshida, Masatoshi,Hayashi, Tamio
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supporting information; experimental part
p. 272 - 279
(2012/03/07)
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- Olefin hydrosilylation catalysts based on allyl Bis(phenolato) complexes of the early lanthanides
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Non-metallocene allyl complexes of early lanthanides (lanthanum, cerium, neodymium, and samarium), that contain a sulfur-linked bis(phenolate) ligand, catalyze the regioselective hydrosilylation of styrene. Copyright
- Abinet, Elise,Spaniol, Thomas P.,Okuda, Jun
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supporting information; experimental part
p. 389 - 391
(2011/10/09)
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- Rare-earth metal alkyl, amido, and cyclopentadienyl complexes supported by Lmidazolin-2-iminato ligands: Synthesis, structural characterization, and catalytic application
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The rare earth metal dichlorides [(1)MCl2(THF)3] (2a, M = Sc; 2b, M = Y; 2c, M = Lu) and the gadolinium complex [(1)GdCl 2(THF)2]·[LiCl(THF)2] (2d), containing the 1,3-bis(2,6-diisopropylphenyl)imidazolin-2-iminato ligand 1, proved to be versatile starting materials for the preparation of trimethylsilylmethyl ("neosilyl") and bis(thmethylsilyl)amido complexes [(1)M(CH 2SiMe3)2(THF)2] (3a-3d) and [(1)M(HMDS)2(THF)] [4a-4d, HMDS = hexamethyldisilazide, N(SiMe 3)2] and for the preparation of the benzyl complex [(1)Lu(CH2Ph)2(THF)2] (5c) by the reaction with LiCH2SiMe3, Na[N(SiMe3)2], and KCH2Ph, respectively. Treatment of 2a-2c with KCp* afforded the mono(pentamethylcyclopentadienyl) complexes [(1)Sc(Cp*)Cl(THF)] (6a), [(1)Y(Cp*)Cl(THF)2] (6b), and [(1)Lu(Cp*)Cl(THF)] (6c). In contrast, the gadolinocene complex [(1)Gd(Cp*)2(THF)] (7) was isolated from the reaction of 2d with 2 equiv of KCp*. The molecular structures of 3a-3d, 4b-THF, 4d, 5c, 6a, 6c, and 7-THF were determined by X-ray diffraction analyses, revealing the presence of exceptionally short metal-nitrogen bonds. The neosilyl complexes 3b and 3c showed high catalytic activity in the intramolecular hydroamination of aminoalkenes and aminoalkynes and in the hydrosilylation of 1-hexene and 1-octene with PhSiH3.
- Trambitas, Alexandra G.,Panda, Tarun K.,Jenter, Jelena,Roesky, Peter W.,Daniliuc, Constantin,Hrib, Cristian G.,Jones, Peter G.,Tamm, Matthias
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experimental part
p. 2435 - 2446
(2010/05/15)
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- Fe-Cu cooperative catalysis in the isomerization of alkyl Grignard reagents
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Alkyl Grignard reagents were found to be isomerized to more stable ones in high isomerization ratios (>99%) under cooperative catalysis by iron and copper, which promote isomerization of alkyl groups and transmetalation between Fe-Mg, respectively. The Ro
- Shirakawa, Eiji,Ikeda, Daiji,Yamaguchi, Shigeru,Hayashi, Tamio
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p. 1214 - 1216
(2008/12/21)
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- Alkene hydrosilation by a cationic hydrogen-substituted iridium silylene complex
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A cationic hydrogen-substituted iridium silylene complex [(PNP)(H)Ir=Si(Mes)H][B(C6F5)4] (2) was synthesized via hydride abstraction from the corresponding neutral iridium silyl hydride complex. DFT calculations for 2 indicate that the cationic charge is localized at the silicon center and depict a LUMO with predominant silicon p-orbital character. Notably, complex 2 reacts rapidly with unhindered alkenes at ambient temperatures to afford disubstituted silylene complexes via Si-C bond formation. Complex 2 is also the catalyst for alkene hydrosilation of primary silanes with a high degree of anti-Markovnikov selectivity. Copyright
- Calimano, Elisa,Tilley, T. Don
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supporting information; body text
p. 9226 - 9227
(2009/02/02)
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- Rare-earth metal alkyl and hydride complexes stabilized by a cyclen-derived [NNNN] macrocyclic ancillary ligand
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A trinuclear rare-earth metal hydride complex was synthesized from the dialkyl complex supported by a monoanionic [NNNN] macrocycle and shown to catalyze the hydrosilylation of olefins efficiently. Copyright
- Ohashi, Masato,Konkol, Marcin,Del Rosal, Iker,Poteau, Romuald,Maron, Laurent,Okuda, Jun
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p. 6920 - 6921
(2008/12/20)
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- Bis(phosphinimino)methanide rare earth amides: Synthesis, structure, and catalysis of hydroamination/cyclization, hydrosilylation, and sequential hydroamination/hydrosilylation
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A series of yttrium and lanthanide amido complexes [Ln{N-(SiHMe 2)2}2{CH(PPh2NSiMe3) 2}] (Ln = Y, La, Sm, Ho, Lu) were synthesized by three different pathways. The title compounds can be obtained either from [Ln{N(SiHMe 2)2}3(thf)2] and [CH 2(PPh2NSiMe3)2] or from KN-(SiHMe2)2 and [Ln(CH(PPh2NSiMe 3)2}-Cl2]2, while in a third approach the lanthanum compound was synthesized in a one-pot reaction starting from K{CH(PPh2NSiMe3)2}, LaCl3, and KN-(SiHMe2)2. All the complexes have been characterized by single-crystal X-ray diffraction. The new complexes, [Ln{N(SiHMe 2)2}2{CH(PPh2NSiMe3) 2}], were used as catalysts for hydroamination/cyclization and hydrosilylation reactions. A clear dependence of the reaction rate on the ionic radius of the center metal was observed, showing the lanthanum compound to be the most active one in both reactions. Furthermore, a combination of both reactions - a sequential hydroamination/hydrosilylation reaction - was also investigated.
- Rastaetter, Marcus,Zulys, Agustino,Roesky, Peter W.
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p. 3606 - 3616
(2008/02/10)
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- Lutetium alkyl and hydride complexes in a non-cyclopentadienyl coordination environment
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Lutetium alkyl complexes [Lu(L)(CH2SiMe3)(THF) n], which contain a sulfur-linked bis(phenolato) ligand such as 2,2′-thiobis(6-tert-butyl-4-methylphenolate) (L = tbmp, 1) or 1,4-dithiabutanediyl-bis(6-tert-butyl-4-methylphe
- Konkol, Marcin,Spaniol, Thomas P.,Kondracka, Malgorzata,Okuda, Jun
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p. 4095 - 4102
(2008/03/12)
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- A bis(phosphinimino)methanide lanthanum amide as catalyst for the hydroamination/cyclisation, hydrosilylation and sequential hydroamination/ hydrosilylation catalysis
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[La{N(SiHMe2)2}2{CH(PPh 2NSiMe3)2}], which was obtained via an amine elimination starting from [CH2(PPh2NSiMe3) 2] and [La{N(SiHMe2)2}3(THF) 2], was used as catalyst for the hydroamination/cyclisation, the hydrosilylation and the sequential hydroamination/hydrosilylation reaction. The Royal Society of Chemistry 2006.
- Rastaetter, Marcus,Zulys, Agustino,Roesky, Peter W.
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p. 874 - 876
(2008/02/08)
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- Preparation and molecular and electronic structures of iron(0) dinitrogen and silane complexes and their application to catalytic hydrogenation and hydrosilation
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Reduction of the five-coordinate iron(II) dihalide complexes ( iPrPDI)FeX2 (iPrPDI = ((2,6-CHMe 2)2C6H3N=CMe)2C 5H3N; X = Cl, Br) with sodium amalgam under 1 atm of dinitrogen afforded the square pyramidal, high spin iron(0) bis(dinitrogen) complex (iPrPDI)Fe(N2)2. In solution, ( iPrPDI)Fe(N2)2 loses 1 equiv of N2 to afford the mono(dinitrogen) adduct (iPrPDI)Fe(N2) 2. Both dinitrogen compounds serve as effective precatalysts for the hydrogenation and hydrosilation of olefins and alkynes. Effecient catalytic reactions are observed with low catalyst loadings (≤0.3 mol %) at ambient temperature in nonpolar media. The catalytic hydrosilations are selective in forming the anti-Markovnikov product. Structural characterization of a high spin iron(0) alkyne and a bis(silane) σ-complex has also been accomplished and in combination with isotopic labeling studies provides insight into the mechanism of both catalytic C-H and catalytic C-Si bond formation.
- Bart, Suzanne C.,Lobkovsky, Emil,Chirik, Paul J.
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p. 13794 - 13807
(2007/10/03)
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- Synthesis and characterization of alkyllanthanum biphenolate complexes as catalysts for hydroamination/cyclization and hydrosilylation
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The homochiral, dimeric biphenolate alkyllanthanum complex [La{(R)-Biphen){CH(SiMe3)2)]2 can be prepared by facile alkane elimination starting from [La(CH(SiMe3)2}3] and enantiopure (R)-3,3′-di-tert-butyl-5, 5′,6,6′-tetramethyl-1,1′-biphenyl-2,2′-diol [H 2{(R)-Biphen}]. Single-crystal X-ray diffraction revealed that the two La{(A)-Biphen}(CH(SiMe3)2} fragments are connected through bridging phenolate groups of the biphenolate ligands. The two different phenolate groups undergo an intramolecular exchange process in solution leading to their equivalence on the NMR timescale. The biphenolate alkyl complex shows high catalytic activity for hydroamination/cyclization of aminoalkenes, similar to previously known lanthanocene catalysts, but only low enantioselectivity. Addition of THF to [La{(R)-Biphen}(CH(SiMe3)2}] 2 leads to a monomeric tris-THF adduct [La{(R)-Biphen}{CH(SiMe 3)2}(THF)3] with higher catalytic activity than the THF-free homochiral dimer in the cyclization of 2,2-dimethylpent-4- enylamine, suggesting that the dimeric structure of the catalyst system prevails under catalytic conditions in the absence of THF. Addition of HN(SiHMe 2)2 to [La{(R)-Biphen}{CH(SiMe3) 2}(THF)3] results in the formation of [La{(R)-Biphen} (N(SiHMe2)2}(THF)3] which is in equilibrium with its homochiral dimer [La{(R)-Biphen}{N(SiHMe2) 2)(THF)]2 at elevated temperatures. The biphenolate alkyl complexes exhibit good catalytic activity and diastereoselectivity in the hydrosilylation of styrene. Hydrosilylation of 1-hexene and norbornene also proceeds with high diastereoselectivity but rather low activity. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004.
- Gribkov, Denis V.,Hampel, Frank,Hultzsch, Kai C.
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p. 4091 - 4101
(2007/10/03)
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- Catalytic Hydrosilylation of Alkenes by a Ruthenium Silylene Complex. Evidence for a New Hydrosilylation Mechanism
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Novel ruthenium and osmium silylene species containing Si?H bonds have been synthesized and characterized by NMR spectroscopy. The ruthenium complex [Cp*(iPr3P)(H)2Ru=Si(H)Ph·Et2O][B(C6F5)
- Glaser, Paul B.,Tilley, T. Don
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p. 13640 - 13641
(2007/10/03)
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- Rare earth alkyl and hydride complexes bearing silylene-linked cyclopentadienyl-phosphido ligands. Synthesis, structures, and catalysis in olefin hydrosilylation and ethylene polymerization
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A series of silylene-linked cyclopentadienyl-phosphido rare earth alkyl and hydride complexes of type Me2Si(C5Me 4)(PR′)LnR (Ln=Y, Yb, Lu; R′=Ph, Cy, C6H 2tBu3-2,4,6; R=CH2
- Tardif, Olivier,Nishiura, Masayoshi,Hou, Zhaomin
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p. 10525 - 10539
(2007/10/03)
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- Synthesis, structures, and alkene hydrosilation activities of neutral tripodal amidozirconium alkyls
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Aminolysis of Zr(CH2C6H5)4 with CH[(CH3)2SiNHAr]3 (Ar = para-tolyl and para-fluorophenyl) affords CH[(CH3)2-SiNAr]3ZrCH2C 6
- Jia, Li,Zhao, Jiquan,Ding, Errun,Brennessel, William W.
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p. 2608 - 2615
(2007/10/03)
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- Hydrosilylation of olefins with monosilane in the presence of lithium aluminum hydride
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Hydrosilylation reactions of 1-hexene and ethylene with SiH4 occurs in the presence of LiAlH4 as a catalyst. Hexylsilane and dihexylsilane were produced from 1-hexene and SiH4. Ethylsilane was produced from ethylene and SiH4. The reaction mechanism involving SiH4 and the alkyl anion, which is formed by the interaction between LiAlH4 and the olefin, has been proposed.
- Kobayashi, Mineo,Itoh, Masayoshi
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p. 1013 - 1014
(2007/10/03)
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