10374-74-0Relevant articles and documents
Untersuchungen von Polymerisation- und Metathese-Reaktionen XIV. Darstellung heterogener, bimetallischer Metathese-Katalysatoren durch Reaktionen von Carbin-Wolfram-Komplexen des Fischer-Typs mit reduziertem Phillips-Katalysator
Weiss, Karin,Denzner, Michael
, p. 273 - 280 (1988)
Reactions of Fischer-type carbyne tungsten complexes X(CO)nWCPh (X=Cl, Br, I, n=4; X=Cp, n=2) with reduced Phillips catalyst, a chromium(II) compound surface-bound to silica, yield heterogeneous bimetallic metathesis catalysts for alkenes.The reactions probably proceed via a cycloaddition of the WC-carbyne bond with the chromium(II) atoms to give dimetallacyclopropene derivatives.The bimetallic catalysts formed by reaction with the halogeno substituted carbyne complexes are very active alkene metathesis catalysts, as demonstrated by the reaction with 1-octene.The original polymerisation activity towards 1-alkenes of the surface-bound chromium(II) atoms disappeared after reaction with carbyne complexes.
A remarkable Mo catalyst for olefin metathesis: Hexagonal mesoporous silica-supported molybdenum oxide (MoO3/HMS)
Ookoshi, Tooru,Onaka, Makoto
, p. 2399 - 2400 (1998)
Hexagonal mesoporous silica-supported molybdenum oxide exhibits much higher catalytic activity for the metathesis of oct-1-ene in the liquid phase, compared with MoO3 on normal porous silica and MoO3 on γ-alumina.
Olefin hydroformylation and kinetic studies using mono- and trinuclear N,O-chelate rhodium(I)-aryl ether precatalysts
Siangwata, Shepherd,Breckwoldt, Nicholas C.C.,Goosen, Neill J.,Smith, Gregory S.
, (2019)
Rh(I)-salicylaldimine-triazole mononuclear (6) and trinuclear (7) complexes based on an aryl-ether scaffold were investigated as precatalysts in the rhodium-catalysed hydroformylation of the terminal olefin, 1-octene, and internal olefins, 7-tetradecene and 4-octene. The complexes generally show good catalytic activity in the hydroformylation of 1-octene at temperatures ranging from 75 °C to 95 °C and syngas pressures of 20 to 40 bar. The precatalysts have excellent stability and could be reused several times using organic solvent nanofiltration under optimum conditions of 85 °C and 40 bar. Kinetic studies using catalyst precursor 6 were investigated by evaluating the effect of temperature, syngas total pressure and catalyst loading on the rate of hydroformylation. The activation energy for the hydroformylation of 1-octene was calculated to be 62 kJ mol?1 and the experimental rate constants were found to be in good agreement with the predicted rate data obtained using a modified fundamental mechanism-based rate model.
First Neutral and Cationic Tungsten Imido Alkylidene N-Heterocyclic Carbene Complexes
Imbrich, Dominik A.,Elser, Iris,Frey, Wolfgang,Buchmeiser, Michael R.
, p. 2996 - 3002 (2017)
The synthesis of W(NAr′)(NHC)(=CHR)(2,5-Me2pyr)2 (1; Ar′: 2,6-iPr2C6H3; NHC: 1,3-diisopropylimidazol-2-ylidene; 2,5-Me2pyr: 2,5-dimethylpyrrolide; R: CMe2Ph), W(NAr′)(NHC)(=CHR)(2,5-Me2pyr)(OC6F5) (2), W(NAr′)(NHC)(=CHR)(OSiPh3)2 (3), [W(NAr′)(NHC)(=CHR)(OSiPh3))(MeCN)+][B(ArF)4 ?] (4; B(ArF)4 ?: B(3,5-(CF3)2C6H3)4 ?), [W(NAr′)(NHC)(=CHR)(2,5-Me2pyr))+][B(ArF)4 ?] (5), [W(NAr′)(NHC)(=CHR)(OC6F5))(tBuCN)+][B(ArF)4 ?] (6), W(NAr′)(NHC)(=CHR)(OtBu)2 (7), [W(NAr′)(NHC)(=CHR)(OtBu)+][B(ArF)4 ?] (8), and W(NAr′)(NHC)(=CHR)(OCMe(CF3)2)2 (9) is described, and the reactivity of the complexes in olefin metathesis and cyclopolymerization is reported. The cationic complexes 4, 5, and 6 showed high productivity and activity in olefin metathesis reactions, with turnover numbers of up to 40 000 and turnover frequencies (TOF5min) of up to 31 s?1, and also substantial functional group tolerance toward esters, nitriles, alcohols, and sulfides, particularly in the cyclopolymerization of α,ω-diynes.
Molybdenum and Tungsten Alkylidene Complexes That Contain a 2-Pyridyl-Substituted Phenoxide Ligand
Sues, Peter E.,John, Jeremy M.,Bukhryakov, Konstantin V.,Schrock, Richard R.,Müller, Peter
, p. 3587 - 3593 (2016)
In the interest of preparing molybdenum and tungsten alkylidene complexes for olefin metathesis that are longer-lived at high temperatures (～150 °C or above), we synthesized complexes that contain a phenoxide ligand with a 2-pyridyl in one ortho position and a mesityl (Mes) or 2,4,6-i-Pr3C6H2 (Trip) in the other ortho position ([MesON]- or [TripON]-, respectively). The alkylidene (neophylidene) complexes that were prepared include W(O)(CHCMe2Ph)(Me2Pyr)(RON) (R = Mes or Trip), Mo(NC6F5)(CHCMe2Ph)(RON)Cl, Mo(N-2,6-Me2C6H3)(CHCMe2Ph)(RON)Cl, Mo(N-t-Bu)(CHCMe2Ph)(RON)Cl, and M(N-2,6-i-Pr2C6H3)(CHCMe2Ph)(TripON)(OTf) (M = Mo or W). The reaction between Mo(NAr)(CHCMe2Ph)(TripON)(OTf) and ethylene yielded an ethylene complex, Mo(NAr)(C2H4)(TripON)(OTf)(ether). All neophylidene complexes were essentially unreactive toward terminal olefins at 22 °C and showed modest homocoupling activity (at 80 or 100 °C) and alkane metathesis activity (at 150 and 200 °C). W(O)(CHCMe2Ph)(Me2Pyr)(MesON) also stereoselectively polymerized several substituted norbornadienes at 100 °C.
A one-pot tandem olefin isomerization/metathesis-coupling (ISOMET) reaction
Dobereiner, Graham E.,Erdogan, Gulin,Larsen, Casey R.,Grotjahn, Douglas B.,Schrock, Richard R.
, p. 3069 - 3076 (2014)
A tandem catalytic reaction has been developed as part of a process to discover tungsten-based olefin metathesis catalysts that have a strong preference for terminal olefins over cis or trans internal isomers in olefin metathesis. This tandem isomerization/terminal olefin metathesis reaction (ISOMET) converts Cn trans internal olefins into C2n-2cis olefins and ethylene. This reaction is made possible with Ru-based "alkene zipper" catalysts, which selectively isomerize trans olefins to an equilibrium mixture of trans and terminal olefins, plus tungsten-based metathesis catalysts that react relatively selectively with terminal olefins to give Z homocoupled products. The most effective catalysts are W(NAr)(C3H6)(pyr)-(OHIPT) (Ar = 2,6-diisopropylphenyl; pyr = pyrrolide; OHIPT = O-2,6-(2,4,6-i-Pr3C6H2)2C6H3) and various [CpRu(P - N)(MeCN)]X (X-= [B(3,5-(CF3)2C6H3)4]-, PF6-, B(C6F5)4-) isomerization catalysts.
An efficient route to biscardanol derivatives and cardanol-based porphyrins via olefin metathesis
Guo, Ying-Cen,Mele, Giuseppe,Martina, Francesca,Margapoti, Eleonora,Vasapollo, Giuseppe,Xiao, Wen-Jing
, p. 5383 - 5390 (2006)
Ru-catalyzed olefin metathesis has been successfully applied to the synthesis of biscardanol derivatives and cardanol-based porphyrins. Using Hoveyda-Grubbs catalyst (C627), the reactions were performed with various cardanol derivatives (2, 5, 7, and 9) to make novel biscardanol derivatives. With the use of the second-generation Grubbs catalyst (C848) and Ti(OiPr)4, the ring-closing metathesis of cardanol-based porphyrin 11 was carried out to afford cyclic cardanol-based porphyrin derivative 12.
Divergent Approach to a Family of Tyrosine-Derived Ru-Alkylidene Olefin Metathesis Catalysts
Gleeson, Ellen C.,Wang, Zhen J.,Jackson, W. Roy,Robinson, Andrea J.
, p. 7205 - 7211 (2015)
A simple and generic approach to access a new family of Ru-alkylidene olefin metathesis catalysts with specialized properties is reported. This strategy utilizes a late stage, utilitarian Hoveyda-type ligand derived from tyrosine, which can be accessed via a multigram-scale synthesis. Further functionalization allows the catalyst properties to be tuned, giving access to modified second-generation Hoveyda-Grubbs-type catalysts. This divergent synthetic approach can be used to access solid-supported catalysts and catalysts that function under solvent-free and aqueous conditions.
Z-selective olefin metathesis reactions promoted by tungsten Oxo alkylidene complexes
Peryshkov, Dmitry V.,Schrock, Richard R.,Takase, Michael K.,Mueller, Peter,Hoveyda, Amir H.
, p. 20754 - 20757 (2011)
Addition of LiOHMT (OHMT = O-2,6-dimesitylphenoxide) to W(O)(CH-t-Bu)(PMe2Ph)2Cl2 led to WO(CH-t-Bu)Cl(OHMT)(PMe2Ph) (4). Subsequent addition of Li(2,5-Me2C4H2N) to 4 yielded yellow W(O)(CH-t-Bu)(OHMT)(Me2Pyr)(PMe2Ph) (5). Compound 5 is a highly effective catalyst for the Z-selective coupling of selected terminal olefins (at 0.2% loading) to give product in >75% yield with >99% Z configuration. Addition of 2 equiv of B(C6F5)3 to 5 afforded a catalyst activated at the oxo ligand by B(C6F 5)3. 5·B(C6F5)3 is a highly active catalyst that produces thermodynamic products (～20% Z).
Olefin metathesis in air using latent ruthenium catalysts: Imidazole substituted amphiphilic hydrogenated ROMP polymers providing nano-sized reaction spaces in water
?ztürk, Bengi ?zgün,Durmu?, Burcu,Karabulut ?ehito?lu, Solmaz
, p. 5807 - 5815 (2018)
Imidazole substituted hydrogenated amphiphilic ROMP polymers were used as both surfactants and ligand precursors for olefin metathesis reactions in water. Amphiphilic ROMP polymers were synthesized using a two-step procedure. Firstly, dimethyl-5-norbornene-2,3-dicarboxylate was polymerized using ring-opening metathesis polymerization (ROMP)/cross-metathesis (CM) in the presence of allyl-PEG5000 methyl ether and a Grubbs 3rd generation (G3) catalyst. Secondly, a one-pot hydrogenation/aminolysis protocol was used for the post-polymerization modification of PEG end-capped polynorbornene derivatives. Hydrogenation reactions were carried out using residual G3 in the presence of formic acid/sodium formate in THF at 70 °C. The aminolysis reaction was carried out without isolation of the hydrogenated polymer, using triazabicyclodecene (TBD) and 1-(3-aminopropyl)-imidazole, forming imidazole substituted hydrogenated amphiphilic ROMP polymers (mod-Amph1) in an efficient manner. G1-mod-Amph1 formed micelle structures in water with an average particle size of 85.95 (±35) nm as determined by transmission electron microscopy (TEM) and dynamic light scattering (DLS) analysis. The diffusion of Grubbs 1st generation (G1) catalyst into the micelle structure has led to the formation of nano-sized catalysts which exhibited a latent characteristic. The diffusion of hydrophobic olefinic substrates into the nano-reaction spaces, followed by activation of the catalyst with HCl led to a very efficient catalytic system for ring-closing metathesis reactions. RCM reactions of various hydrophobic dienes can run in non-degassed water under an air atmosphere. The catalyst system exhibits similar performance under an air atmosphere even in tap water, reaching a conversion value of 90% for RCM of diethyl diallylmalonate with a catalytic loading of 1% Ru.
