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.
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.
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.
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.
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).
Hoveyda-Grubbs catalyst confined in the nanocages of SBA-1: Enhanced recyclability for olefin metathesis
Yang, Hengquan,Ma, Zhancheng,Wang, Yuekui,Wang, Yunwei,Fang, Li
, p. 8659 - 8661 (2010)
Via a simple adsorption, the second generation Hoveyda-Grubbs catalyst was successfully immobilized on a mesoporous material SBA-1, leading to a highly recyclable solid catalyst for olefin metathesis.
Thermally stable, latent olefin metathesis catalysts
Thomas, Renee M.,Fedorov, Alexey,Keitz, Benjamin K.,Grubbs, Robert H.
, p. 6713 - 6717 (2011)
Highly thermally stable N-aryl, N-alkyl N-heterocyclic carbene (NHC) ruthenium catalysts were designed and synthesized for latent olefin metathesis. These catalysts showed excellent latent behavior toward metathesis reactions, whereby the complexes were inactive at ambient temperature and initiated at elevated temperatures, a challenging property to achieve with second-generation catalysts. A sterically hindered N-tert-butyl substituent on the NHC ligand of the ruthenium complex was found to induce latent behavior toward cross-metathesis reactions, and exchange of the chloride ligands for iodide ligands was necessary to attain latent behavior during ring-opening metathesis polymerization (ROMP). Iodide-based catalysts showed no reactivity toward ROMP of norbornene-derived monomers at 25 °C and upon heating to 85 °C gave complete conversion of monomer to polymer in less than 2 h. All of the complexes were very stable to air, moisture, and elevated temperatures up to at least 90 °C and exhibited a long catalyst lifetime in solution at elevated temperatures.
Continuous-flow alkene metathesis: The model reaction of 1-octene catalyzed by Re2O7/γ-Al2O3 with supercritical CO2 as a carrier
Selva, Maurizio,Guidi, Sandro,Perosa, Alvise,Signoretto, Michela,Licence, Pete,Maschmeyer, Thomas
, p. 2727 - 2737,11 (2012)
In the presence of Re2O7 supported on γ-Al 2O3, the self-metathesis of 1-octene was conveniently carried out under continuous-flow (CF) conditions using supercritical CO 2 (scCO2) as a carrier. This investigation allowed optimization of reaction parameters, the best values of which were found to be 100 °C and 90 bar, operating at flow rates of 0.05 and 1 mL min-1 for 1-octene and scCO2, respectively, the reaction proceeded with very good self-metathesis selectivity (>90%) and an average productivity of ～0.24 mL tetradecene gRe-1 min-1. Although the catalyst was completely deactivated after the first 100-150 min of reaction, it could be recycled for (at least) five subsequent reactions without any loss of performance. The results provided incontrovertible evidence that for the investigated reaction, scCO2was a superior carrier with respect to conventional liquids, such as toluene or n-hexane.
A General and Stereospecific Synthesis of Cis Alkenes via Stepwise Hydroboration: A Simple Synthesis of Muscalure, the Sex Pheromone of the Housefly (Musca domestica)
Brown, Herbert C.,Basavaiah, D.
, p. 3806 - 3808 (1982)
Base-induced iodination of the vinylborane intermediates, conveniently obtained via hydroboration of 1-alkynes with alkylbromoboranes (RBHBr*SMe2) provides cis-disubstituted alkenes in good yields.Muscalure, the insect pheromone of the housefly (Musca domestica), has been prepared in 59percent yield.
Encapsulation of an olefin metathesis catalyst in the nanocages of SBA-1: Facile preparation, high encapsulation efficiency, and high activity
Yang, Hengquan,Ma, Zhancheng,Zhou, Ting,Zhang, Wenjuan,Chao, Jianbin,Qin, Yong
, p. 2278 - 2287 (2013)
By postreducing the window size through silylation, 2nd generation Hoveyda-Grubbs catalyst was encapsulated in the nanocages of a mesoporous material SBA-1. The encapsulation efficiency of SBA-1 was up to 70%, much higher than that of other mesoporous materials such as SBA-16, FDU-12, and MCM-41 (0-43%). The successful encapsulation was confirmed by N2 sorption analysis and FTIR and diffusion reflectance UV/Vis spectroscopy. Such a SBA-1-encapsulated catalyst showed good activity in both olefin ring-closing metathesis and cross metathesis. A wide range of olefins could be transformed to the desired products with conversions of 27-100%. The encapsulated catalyst showed more sensitive temperature effects than the homogeneous counterpart, reflecting the unique properties of the encapsulated catalyst. At reaction temperatures of 40-60°C, the activity of the encapsulated catalyst was sufficiently comparable to that of the homogeneous catalyst for the cross metathesis of styrene-type substrates, probably because of the confinement effects of the nanocages. The solid catalyst could be recycled seven times. This study not only supplies a new solid catalyst for olefin metathesis but also demonstrates our improvement in immobilizing metal complex catalyst toward a green and effective level.
Z-Selective Monothiolate Ruthenium Indenylidene Olefin Metathesis Catalysts
Smit, Wietse,Ekeli, Jonas B.,Occhipinti, Giovanni,Wo?niak, Bartosz,T?rnroos, Karl W.,Jensen, Vidar R.
, p. 397 - 407 (2020)
Ru-alkylidenes bearing sterically demanding arylthiolate ligands (SAr) constitute one of only two classes of catalyst that are Z-selective in metathesis of 1-alkenes. Of particular interest are complexes bearing pyridine as a stabilizing donor ligand, [RuCl(SAr)(a? CHR)(NHC)(py)] (R = phenyl or 2-thienyl, NHC = N-heterocyclic carbene, py = pyridine), which initiate catalysis rapidly and give appreciable yields combined with moderate to high Z-selectivity within minutes at room temperature. Here, we extend this chemistry by synthesizing and testing the first two such complexes (5a and 5b) bearing 3-phenylindenylidene, a ligand known to promote stability in other ruthenium-based olefin metathesis catalysts. The steric pressure resulting from the three bulky ligands (the NHC, the arylthiolate, and the indenylidene) forces the thiolate ligand to position itself trans to the NHC ligand, a configuration different from that of the corresponding alkylidenes. Surprisingly, although this configuration is incompatible with Z-selectivity and slows down pyridine dissociation, the two new complexes initiate readily at room temperature. Although their thermal stability is lower than that of typical indenylidene-bearing catalysts, 5a and 5b are fairly stable in catalysis (TONs up to 2200) and offer up to ca. 80% of the Z-isomer in prototypical metathesis homocoupling reactions. Density functional theory (DFT) calculations confirm the energetic cost of dissociating pyridine from 5a (= M1-Py) to generate 14-electron complex M1. Whereas the latter isomer does not give a metathesis-potent allylbenzene ?-complex, it may isomerize to M1-trans and M2, which both form ?-complexes in which the olefin is correctly oriented for cycloaddition. The olefin orientation in these complexes is also indicative of Z-selectivity.
Synthesis and characterization of a homogeneous and silica supported homoleptic cationic tungsten(VI) methyl complex: Application in olefin metathesis
Dey, Raju,Samantaray, Manoja K.,Poater, Albert,Hamieh, Ali,Kavitake, Santosh,Abou-Hamad, Edy,Callens, Emmanuel,Emwas, Abdul-Hamid,Cavallo, Luigi,Basset, Jean-Marie
, p. 11270 - 11273 (2016)
A method for the synthesis of a homogeneous cationic tungsten(vi)pentamethyl complex [(WMe5)+(C6F5)3BMe-] from neutral tungstenhexamethyl (WMe6) and a silica supported cationic tungstentetramethyl complex [(Si-O-)WMe4+ (C6F5)3BMe-] from a neutral silica supported tungstenpentamethyl complex [(Si-O-)WMe5] is described. In both cases a direct demethylation using the B(C6F5)3 reagent was used. The aforesaid complexes were characterized by liquid or solid state NMR spectroscopy. Interestingly, the homogeneous cationic complex [(WMe5)+(C6F5)3BMe-] shows moderate activity whereas the supported cationic complex [(Si-O-)WMe4+(C6F5)3BMe-] exhibits good activity in olefin metathesis reactions.
Ruthenium catalyst with a chelating pyridinyl-alcoholato ligand for application in linear alkene metathesis
Jordaan, Margaritha,Vosloo, H. C. Manie
, p. 184 - 192 (2007)
The catalytic activity of ruthenium alkylidene complexes [RuCl(LX(ON)(=CHPh)] [L = H2IMes and PCy3, ON = 1-(2′-pyridinyl)cyclohexan-1-olate)], bearing a chelating pyridinyl-alcoholate ligand, was investigated for the metathesis of 1-octene in the absence of a solvent. Both systems were active for the metathesis of 1-octene yielding trans-7-tetradecene and ethene as the primary metathesis products. Although the activity of both systems increased with an increase in reaction temperature, the activity of [RuCl(H2IMes)(ON)(=CHPh)] started to decrease at temperatures above 70°C, with a simultaneous exponential increase in the secondary metathesis products due to double-bond isomerisation of the substrate. Although the initiation rates for these systems are slower compared to Grubbs 1 and Grubbs 2 for the metathesis of 1-octene at 60°C, they have a higher activity and longer lifetime.
Phosphabicyclononane-containing Ru complexes: Efficient pre-catalysts for olefin metathesis reactions
Boeda, Fabien,Clavier, Herve,Jordaan, Margaritha,Meyer, Wolfgang H.,Nolan, Steven P.
, p. 259 - 263 (2008)
(Chemical Equation Presented) The catalytic performances of three Phosphabicyclononane (Phoban)-containing ruthenium-based pre-catalysts have been evaluated for metathesis transformations. A wide screening of substrates in ring-closing metathesis reactions reveals the greater efficiency of pre-catalyst 4. Comparison of the catalytic activities of 4 with Grubbs' first-generation pre-catalyst illustrates the key role of the Phoban ligand. Additionally, a comparative study of three Phoban-containing pre-catalysts has been conducted for the self-metathesis of 1-octene at low catalyst loading (25-100 ppm).
Functionality dependent olefin activity in acyclic diene metathesis polymerization: Mass spectrometry characterization of amino acid functionalized olefins
Petkovska, Violeta I.,Hopkins, Timothy E.,Powell, David H.,Wagener, Kenneth B.
, p. 3624 - 3631 (2006)
Mass spectrometry has become an essential tool in delineating the structural properties of a new series of amino acid functionalized acyclic diene metathesis (AD-MET) polymers known as bioolefins. These measurements, coupled with the measurement of the polymers chemical and physical properties, assist in the determination of their utility as biomaterials. In the present study, a set of five polymers with different bulk size and electronic properties were chosen for structural analyses by MALDI-TOF, MALDI-FTICR, and DIOS-TOF. The obtained data show that due to the competing metathesis and isomerization during ADMET, depending on their structural properties, the olefins display different selectivity toward main metathesis or isomerized products.
Lewis acid-modified mesoporous alumina: A new catalyst carrier for methyltrioxorhenium in metathesis of olefins bearing functional groups
Oikawa, Takashi,Masui, Yoichi,Tanaka, Tsunehiro,Chujo, Yoshiki,Onaka, Makoto
, p. 554 - 561 (2007)
Lewis acid-modified mesoporous alumina was found to be an efficient carrier as well as an activator for methyltrioxorhenium (MeReO3) in olefin metathesis reactions. Especially, MeReO3 doped on zinc chloride-modified mesoporous alumina catalyzed the metathesis of olefins with functional groups such as acetoxy, alkoxycarbonyl, acyl, chlorine, and bromine groups under mild conditions. The novel heterogeneous catalytic system promoted the metathesis of not only such functionalized olefins but also simple olefins without double bond migration that was often encountered on strong solid acids. We here present a new methodology for activation of a metal complex with Lewis acidic mesoporous materials in the metathesis reactions. This novel heterogeneous catalyst would be advantageous over conventional one from the viewpoint of environmental and economical organic synthesis.
Determination of Double Bonds and Isomer Purity of Olefins
Heckelsberg, Louis F.
, p. 398 - 400 (1983)
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Kinetics of α-olefin metathesis over the heterogeneous catalytic system (MoOCL4/SiO2)-SnMe4
Bykov,Belyaev,Butenko,Finkelshtein
, p. 353 - 356 (2012)
The kinetics of 1-hexene and 1-octene metathesis over the (MoOCl4/SiO 2)-SnMe4 catalytic sys- tem at 27 and 50°C has been investigated. The rate constants of the forward and reverse reactions and the cat- alyst deactivation constants have been measured. The number of active sites has been determined to be 10- 13 mol % of the total number of molybdenum atoms. Pleiades Publishing, Ltd., 2012.
SYNTHESIS OF PHEROMONE DERIVATIVES VIA Z-SELECTIVE OLEFIN METATHESIS
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Paragraph 0222; 0233, (2021/12/28)
Disclosed herein are methods for synthesizing fatty olefin metathesis products of high Z-isomeric purity from olefin feedstocks of low Z-isomeric purity. The methods include contacting a contacting an olefin metathesis reaction partner, such as acylated alkenol or an alkenal acetal, with an internal olefin in the presence of a Z-selective metathesis catalyst to form the fatty olefin metathesis product. In various embodiments, the fatty olefin metathesis products are insect pheromones. Pheromone compositions and methods of using them are also described.
Continuous Flow Z-Stereoselective Olefin Metathesis: Development and Applications in the Synthesis of Pheromones and Macrocyclic Odorant Molecules**
Browne, Duncan L.,Colombel-Rouen, Sophie,Crévisy, Christophe,Curbet, Idriss,Mauduit, Marc,McBride, Tom,Morvan, Jennifer,Roisnel, Thierry
supporting information, p. 19685 - 19690 (2021/08/06)
The first continuous flow Z-selective olefin metathesis process is reported. Key to realizing this process was the adequate choice of stereoselective catalysts combined with the design of an appropriate continuous reactor setup. The designed continuous process permits various self-, cross- and macro-ring-closing-metathesis reactions, delivering products in high selectivity and short residence times. This technique is exemplified by direct application to the preparation of a range of pheromones and macrocyclic odorant molecules and culminates in a telescoped Z-selective cross-metathesis/ Dieckmann cyclisation sequence to access (Z)-Civetone, incorporating a serial array of continually stirred tank reactors.
Dehydrogenative alcohol coupling and one-pot cross metathesis/dehydrogenative coupling reactions of alcohols using Hoveyda-Grubbs catalysts
?zer, Halenur,Arslan, Dilan,?ztürk, Bengi ?zgün
, p. 5992 - 6000 (2021/04/12)
In this study,in situformed ruthenium hydride species that were generated from Grubbs type catalysts are used as efficient catalysts for dehydrogenative alcohol coupling and sequential cross-metathesis/dehydrogenative coupling reactions. The selectivity of Grubbs first generation catalysts (G1) in dehydrogenative alcohol coupling reactions can be tuned for the ester formation in the presence of weak bases, while the selectivity can be switched to the β-alkylated alcohol formation using strong bases. The performance of Hoveyda-Grubbs 2nd generation catalyst (HG2) was improved in the presence of tricyclohexylphosphine for the selective synthesis of ester derivatives with weak and strong bases in quantitative yields. Allyl alcohol was used as self and cross-metathesis substrate for the HG2 catalyzed sequential cross-metathesis/dehydrogenative alcohol coupling reactions to obtain γ-butyrolactone and long-chain ester derivatives in quantitative yields.
