F:Flammable;111-65-9Relevant articles and documents
Production of Alcohols from Olefins via One-Pot Tandem Hydroformylation-Acetalization-Hydrogenolysis over Bifunctional Catalyst Merging RuIII-P Complex and RuIII Lewis Acid
Wang, Peng,Wang, Dong-Liang,Liu, Huan,Zhao, Xiao-Li,Lu, Yong,Liu, Ye
, p. 2404 - 2411 (2017)
A novel three-step tandem hydroformylation-acetalization-hydrogenolysis was first proposed to produce alcohols (derivatives) from olefins, and the developed unique Ru(III)-complex [Ru(III)-L2] ligated by the ionic diphosphine (L2) proved efficient toward this tandem reaction. In Ru(III)-L2, the strong π-acceptor nature of L2 guaranteed Ru-center remaining in +3 valence state without redox reaction. Hence, Ru(III)-L2 was able to behave as a bifunctional catalyst merging RuIII-P complex and RuIII Lewis acid, which acted not only as a transition metal catalyst responsible for hydroformylation of olefins and hydrogenolysis of (hemi)acetals but also as a Ru3+ Lewis acid in charge of acetalization of aldehydes [to form (hemi)acetals]. The easily performed acetalization served as a bridge step to get through the pathway from aldehydes to alcohols instead of the direct hydrogenation.
Alkyne hydrogenation using Pd-Ag hybrid nanocatalysts in surface-immobilized dendrimers
Karakhanov, Edward A.,Maximov, Anton L.,Zolotukhina, Anna V.,Yatmanova, Nadezhda,Rosenberg, Edward
, p. 777 - 784 (2015)
A series of Pd-Ag mixed-metal nanocatalysts were prepared by reduction of Pd-Ag salts in the presence of poly(propylene imine) dendrimers, which were covalently bound to the surface of a silica polyamine composite, BP-1 (polyallylamine covalently bound to a silanized amorphous silica gel). Three different Pd-to-Ag ratios were evaluated (50:50, catalyst 1; 40:60, catalyst 2; 60:40, catalyst 3) with the goal of determining how the amount of Ag effects selectivity, rate and conversion in the selective reduction of alkynes, such as phenylacetylene and 1- or 4-octyne, to the corresponding alkenes. Conditions for the catalysis are reported where there is improved selectivity without a serious reduction in rate when compared with the analogous Pd-only catalysts. Catalyst 2 worked best for phenylacetylene and catalyst 3 worked best for the octynes. The catalysts could be reused seven times without loss of activity.
Catalytic and supported Barton-McCombie deoxygenation of secondary alcohols: A clean reaction
Boussaguet, Paul,Delmond, Bernard,Dumartin, Gilles,Pereyre, Michel
, p. 3377 - 3380 (2000)
Secondary alcohols were deoxygenated using a new version of the Barton- McCombie process involving a catalytic amount of supported tin hydride in the presence of trimethoxysilane. The products are then easily separated from the catalyst by a simple filtration avoiding pollution by toxic tin by-products. (C) 2000 ElSevier Science Ltd.
Ashby et al.
, p. 3695 (1977)
Mechanism of the isomerization of 1-alkene during iron-catalyzed Fischer-Tropsch synthesis
Shi, Buchang,O'Brien, Robert J.,Bao, Shiqi,Davis, Burtron H.
, p. 202 - 208 (2001)
The deuterium/hydrogen exchange reaction was conducted under iron-catalyzed Fischer-Tropsch reaction conditions using a mixture of deuterated octane, nonane, decane, tridecane, and pentadecane as the probes. The deuterium/hydrogen exchange did not occur in alkanes under these conditions. Under the same reaction conditions, 1-octene-d16 was used as the probe to study the isomerization of 1-alkene. The 1-octene-d16 was reduced to deuterated octane, and isomerized to deuterated trans-2-octene and cis-2-octene with nearly equal amounts of the two isomers. Products from cracking and isomerization to internal octenes other than the 2-octene isomers did not occur to a measurable extent. When 1-octene-d16 was used as the probe, there was H/D exchange in octenes and octane; the lowest deuterium-containing isomer products were the d11 isotopomers, and there were no d16 isomers in the 2-octenes.
Hydrogenation of dienes by a recyclable poly(ethylene oxide)-rhodium phosphineless catalytic system
Tavares, Aline,Wolke, Silvana I.,da Rosa, Ricardo Gomes
, p. 374 - 382 (2008)
The monocationic complex [(η5-Cp*)2Rh2(μ2-Cl)3]PF6 in poly(ethylene oxide) (PEO) 3350/MeOH has proven to be a very efficient catalyst for 1,7-octadiene, 1,9-decadiene, and 1,5-cyclooctadiene hydrogenation. This system allows perfect product separation and catalyst phase recycling, resulting in thousands of catalytic cycles (TON ≈ 9000). Even at room temperature, turnover frequencies as high as 5000 h-1 are attained (50 bar), which makes this one of the most active catalytic systems for diene hydrogenation. Kinetic studies reveal that the reaction rate is second-order in H2 pressure and first-order in both rhodium and diene concentrations. Typical tests suggest that, despite the reductive reaction conditions, which could lead to colloidal metal dispersion, the reduction of dienes is catalyzed by molecular species.
A SIMPLE, EFFICIENT METHOD FOR THE PURIFICATION OF POTASSIUM HYDRIDE AND ITS ROLE IN NEW BOROHYDRIDE CHEMISTRY
Soderquist, John A.,Rivera, Isaac
, p. 3195 - 3196 (1988)
KH can be purified with LiAlH4 in THF providing a highly active material wich quantitatively converts even hindered trialkylboranes to the corresponding borohydrides, borinate esters to dialkylborohydrides and reduces, with a catalytic amount of a trialkylborane, 1-bromoalkanes.
Hypervalent iodine in carbon-carbon bond forming reactions. A new reaction of hypervalent iodine compounds and organolithium reagents
Barton,Jaszberenyi Cs.,Lessmann,Timar
, p. 8881 - 8890 (1992)
Hypervalent iodine compounds react with organolithium reagents instantaneously even at -80°C resulting in the formation of hydrocarbons. Our findings indicate that the carbon-carbon bond formation is the result of ligand exchange and second displacement on the carbon bonded to iodine.
Improvement on the catalytic performance of Mg-Zr mixed oxides for furfural-acetone aldol condensation by supporting on mesoporous carbons
Faba, Laura,Diaz, Eva,Ordonez, Salvador
, p. 463 - 473 (2013)
A new procedure for improving the performance of the most common catalysts used in aqueous-phase aldol condensation (Mg-Zr mixed oxides) reactions is presented. This reaction is of interest for upgrading carbohydrate feedstocks. The procedure involves supporting Mg-Zr oxides on non-microporous carbonaceous materials, such as carbon nanofibers (CNFs) or high-surface-area graphites (HSAGs), using either incipient wetness or coprecipitation procedures. The use of HSAGs together with the coprecipitation method provides the best performance. Results obtained for the cross-condensation of acetone and furfural at 323K reveal that the catalyst performance is greatly improved compared to the bulk oxides (96.5 % conversion vs. 81.4 % with the bulk oxide; 87.8 % selectivity for C13 and C8 adducts vs. 76.2 % with the bulk oxide). This difference is even more prominent in terms of rates per catalytically active basic site (four and seven times greater for C8 and C13 adducts, respectively). The improved performance is explained in terms of a more appropriate basic site distribution and by greater interaction of the reactants with the carbon surface. In addition, deactivation behavior of the catalyst is improved by tuning the morphology of the carbonaceous support. An important enhancement of the catalytic stability can be obtained selecting a HSAG with an appropriate pore diameter. With HSAG100 the activity decreased by less than 20 % between successive reaction cycles and the selectivity for the condensation products remained almost unaltered. The decrease is greater than 80 % for the bulk oxides tested at these conditions, with important increases in the selectivity for by-product formation. Copyright
Tailorable synthesis of porous organic polymers decorating ultrafine palladium nanoparticles for hydrogenation of olefins
Li, Liuyi,Zhao, Huaixia,Wang, Ruihu
, p. 948 - 955 (2015)
Two 1,2,3-triazolyl-containing porous organic polymers (CPP-C and CPP-Y) were readily synthesized through click reaction and Yamamoto coupling reaction, respectively. The effects of synthetic methods on the structures and properties of CPP-C and CPP-Y were investigated. Their chemical compositions are almost identical, but their physical and texture properties are different from each other. Ultrafine palladium nanoparticles can be effectively immobilized in the interior cavities of CPP-C and CPP-Y. The interactions between polymers and palladium are verified by IR, solid-state NMR, XPS, and EDS. Their catalytic performances are evaluated by hydrogenation of olefins. Pd@CPP-Y exhibits higher catalytic activity and recyclability than Pd@CPP-C. Hot filtration and the three-phase test indicate that hydrogenation functions in a heterogeneous pathway. (Figure Presented).
Synthetic and structural studies of NHC-Pt(dvtms) complexes and their application as alkene hydrosilylation catalysts (NHC = N-heterocyclic carbene, dvtms = divinyltetramethylsiloxane)
Berthon-Gelloz, Guillaume,Buisine, Olivier,Brière, Jean-Fran?ois,Michaud, Guillaume,Stérin, Sébastien,Mignani, Gérard,Tinant, Bernard,Declercq, Jean-Paul,Chapon, David,Markó, István E.
, p. 6156 - 6168 (2005)
The synthesis and structural characterization of a series of platinum complexes, bearing N-heterocyclic carbenes (NHC) and divinyltetramethylsiloxane (dvtms) as supporting ligands, are described. The reaction of commercially available Karstedt's catalyst
Fast Halogen Abstraction from Alkyl Halides by Alkyl Radicals. Quantitation of the Processes Occurring in and a Caveat for Studies Employing Alkyl Halide Mechanistic Probes
Newcomb, Martin,Sanchez, Robert M.,Kaplan, Jere
, p. 1195 - 1199 (1987)
Second-order rate constants for halogen atom transfer (kRX) in benzene at 50 deg C were determined for reactions of octyl radical with tert-butyl, isopropyl, and cyclohexyl iodides and bromides and with ethyl iodide, n-butyl bromide, tert-butyl chloride, and carbon tetrachloride using two methods.In method A, an aklyl iodide and tributylstannane were allowed to compete for octyl radical in radical-chain reactions; in method B, an alkyl halide competed with 1-(oxononoxy)-2(1H)-pyridinethione (1) for octyl radical.The values for kRX were calculated from the product distributions, the reactant ratios, and the known rate constants for reaction of tributylstannane or 1 with octyl radical.The possibility that rearranged products can be formed in reactions of alkyl halide mechanistic probes with nucleophiles via a sequence involving radical-chain isomerization that converts the probe halide into a rearranged halide followed by nucleophilic attack on the isomerized halide is discussed as are possible chain-terminating reactions.The conclusion is reached that the percentage of rearranged substitution products formed in reactions of alkyl halide mechanistic probes with nucleophiles can give misleading information about the number of radical-initiating events.
Reactions fo Alkyllithium and Grignard Reagents with Benzoquinone: Evidence for and Electron-Transfer Mechanism
McKinley, Jason,Aponick, Aaron,Raber, Jaffrey C.,Fritz, Christine,Montgomery, David,Wigal, Carl T.
, p. 4874 - 4876 (1997)
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Truitt et al.
, p. 1107 (1957)
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Dinuclear Ruthenium Complexes as Active Catalyst Precursors for the Low Pressure Hydroformylation of Alkenes into Aldehydes
Jenck, Jean,Kalck, Philippe,Pinelli, Eric,Siani, Michel,Thorez, Alain
, p. 1428 - 1430 (1988)
Di-μ-acetato diruthenium complexes catalyse the low pressure hydroformylation of alkenes to give the corresponding aldehydes with high selectivities.
Reducing Alkyl Halides Using a Polymer-Bound Crown Ether/Tin Hydride Cocatalyst
Blanton, James R.,Salley, Joseph M.
, p. 490 - 491 (1991)
In this paper the synthesis and application of a novel macromolecular cocatalyst in which both reactive sites are on the same polymer matrix is described.Using this macromolecular cocatalyst, it was found that alkyl halide groups could be conveniently transformed into the corresponding hydrocarbon moiety in moderate yields.
DIRECT PHOTOLYSIS AT 185 nm OF 1-ALKENES IN SOLUTION. MOLECULAR ELIMINATION OF TERMINAL HYDROGENS
Inoue, Yoshihisa,Mukai, Toshio,Hakushi, Tadao
, p. 1725 - 1728 (1984)
Direct irradiations at 185 nm of 1-octene and 2-methyl-1-pentene in pentane gave alkylidene carbenes through the molecular elimination of terminal hydrogens, as well as double-bond migration products via 1,3-shift of allylic hydrogen and radical-derived products.
In Situ Generation and Immobilization of an Activated Rh Complex Catalyst in a Metal–Organic Framework for Hydrogenation at Low H2 Pressure
Takashima, Yohei,Fukuhara, Yoshimasa,Sato, Yasushi,Tsuruoka, Takaaki,Akamatsu, Kensuke
, p. 5344 - 5349 (2017)
Hydrogenation reactions under low-pressure H2 atmosphere are highly relevant from the safety viewpoint, because H2 gas is highly flammable in air and explosions can be triggered by spark, heat, or sunlight. In this work, an Rh complex/MOF hybrid was synthesized and used as catalyst for the hydrogenation of alkene substrates. Thanks to the activation of the Rh complex catalyst during the immobilization process and the intrinsic gas-condensation property of MOFs, the resulting composite showed much higher catalytic activity than the complex catalyst itself. Moreover, the composite can maintain its catalytic activity even at low H2 pressures that cannot support the reaction with the complex catalyst alone. Furthermore, in contrast to the complex catalyst, the composite maintained its catalytic activity even without solvent, and thus provides an environmentally friendly approach to catalysis.
Kinetics of hydrodeoxygenation of octanol over supported nickel catalysts: A mechanistic study
Chandra Sekhar Palla, Venkata,Shee, Debaprasad,Maity, Sunil K.
, p. 41612 - 41621 (2014)
The hydrodeoxygenation (HDO) of 1-octanol as a model aliphatic alcohol of bio-oil was investigated in a continuous down-flow fixed-bed reactor over γ-Al2O3, SiO2, and HZSM-5 supported nickel catalysts in the temperature range of 488-533 K. The supported nickel catalysts were prepared by incipient wetness impregnation method and characterized by BET, XRD, TPR, TPD, H2pulse chemisorption, and UV-vis spectroscopy. Characterization of supported nickel (or nickel oxide) catalysts revealed existence of dispersed as well as bulk nickel (or nickel oxide) depending on the extent of nickel loading and the nature of the support. The acidity of γ-Al2O3supported nickel catalysts decreased with increasing the nickel loading on γ-Al2O3. n-Heptane, n-octane, di-n-octyl ether, 1-octanal, isomers of heptene and octene, tetradecane, and hexadecane were identified as products of HDO of 1-octanol. The C7hydrocarbons were observed as primary products for catalysts with active metal sites such as γ-Al2O3and SiO2supported nickel catalysts. However, C8hydrocarbons were primarily formed over acidic catalysts such as pure HZSM-5 and HZSM-5 supported nickel catalyst. The 1-octanol conversion increased with increasing nickel loading on γ-Al2O3, and temperature and decreasing pressure and WHSV. The selectivity to products was strongly influenced by temperature, nickel loading on γ-Al2O3, pressure, and types of carrier gases (nitrogen and hydrogen). The selectivity to C7hydrocarbons was favoured over catalysts with increased nickel loading on γ-Al2O3at elevated temperature and lower pressure. A comprehensive reaction mechanism of HDO of 1-octanol was delineated based on product distribution under various process conditions over different catalysts. This journal is
Noble metal-free catalytic decarboxylation of oleic acid to n-heptadecane on nickel-based metal-organic frameworks (MOFs)
Yang,McNichols,Davidson,Schweitzer,Gómez-Gualdrón,Trewyn,Sellinger,Carreon
, p. 3027 - 3035 (2017)
Nickel based metal organic frameworks (Ni-MOFs) were successfully synthesized using new conjugated carboxylic acid linkers. These conjugated carboxylic acid linkers were synthesized using mild Heck coupling that led to the incorporation of functional groups not possible by traditional synthetic methods. Control of linker size allows for porosity tuning of the crystalline network and high surface area, that, in theory, results in the increased accessibility to Ni metal centers for catalysis. The resultant crystalline Ni-MOFs displayed BET areas as high as ～314 m2 g-1. To investigate their catalytic activity for conversion of oleic acid to liquid hydrocarbons, Ni-MOFs were grown on zeolite 5A beads that served as catalytic supports. The resultant catalysts displayed heptadecane selectivity as high as ～77% at mild reaction conditions, one of the highest yields for non-noble metal containing catalysts. The catalytic activity correlated to the concentration of acid sites. A slight decrease in catalytic activity was observed after catalysts recycling.
Oligomerization of 1-butene with a homogeneous catalyst system based on allylic nickel complexes
Behr,Bayrak,Peitz,Stochniol,Maschmeyer
, p. 41372 - 41376 (2015)
The oligomerization of 1-butene with a nickel-based catalyst system constitutes an elegant synthesis method for obtaining linear octenes from readily available chemicals. It is well known that the bis-(cyclooctadiene)nickel(0)-complex (Ni(COD)2) can be used in combination with 1,1,1,5,5,5-hexafluoroacetylacetone (hfacac) forming [Ni-1] as a catalyst for the dimerization of 1-butene, which produces a linear octene yield of 75-83% at reaction temperatures between 70-80 °C. We are the first to demonstrate that it is also possible to use allylic nickel complexes in combination with hfacac to produce linear octenes with a selectivity of 70% under very mild reaction conditions and at low catalyst concentrations. Additionally the catalyst can be formed simply by adding the activator hfacac to a solution of the allylic nickel complex. No complicated synthesis or purification is needed.
Activation of Reducing Agents. Sodium Hydride Containing Complex Reducing Agents. 15. Reduction and Selective Reduction of Organic Halides
Vanderesse, Regis,Brunet, Jean-Jacques,Caubere, Paul
, p. 1270 - 1277 (1981)
The reduction of alkyl and vinyl halides with a reducing system composed of NaH, alkoxides, and metal salts ("complex reducing agents", CRA) has been investigated.The reagent system efficiently converts primary, secondary, and tertiary alkyl iodides, bromides, and chlorides to the corresponding hydrocarbons.Alkyl tosylates are less readily attacked, and fluorides are inert.Benzyl, allyl, and vinyl halides are also reduced.The latter react stereospecifically without double bond isomerization.Selective reductions of mixtures of alkyl halides are possible with eitherNi CRA or Zn CRA, and the reagents are inert toward a number of other functional groups, allowing selective reductions to be achieved.Finally, the reduction may be achieved by using catalytic amounts of nickel salts.Possible structures for the complex reducing agents are discussed, as well as suggested mechanisms for halide reductions.
Promotional effect of Fe on performance of Ni/SiO2 for deoxygenation of methyl laurate as a model compound to hydrocarbons
Yu, Xinbin,Chen, Jixiang,Ren, Tianyu
, p. 46427 - 46436 (2014)
Ni/SiO2, Fe/SiO2 and bimetallic FeNi/SiO2 catalysts with different Fe/Ni weight ratios were prepared by incipient-wetness impregnation method for the deoxygenation of methyl laurate to hydrocarbons. It was found that a suitable amount of Fe enhanced the activity of Ni/SiO2 for the deoxygenation of methyl laurate, and FeNi(0.25)/SiO2 with a Fe/Ni weight ratio of 0.25 showed the best activity. Moreover, the addition of Fe to Ni/SiO2 significantly promoted the hydrodeoxygenation pathway to produce more C12 hydrocarbon and suppressed the activity for C-C hydrogenolysis. The effect of Fe on the performance of Ni/SiO2 is ascribed the formation of the NiFe alloy particles, particularly with the Fe-enriched surface at low Fe content, and the existence of oxygen vacancies in Fe oxides. A mechanism is proposed to explain the promoting effect of Fe, which involves the synergism between iron sites with strong oxophilicity and nickel sites with high ability to activate hydrogen. Besides, the effect of reaction conditions and catalyst stability were also investigated.
Flitcroft et al.
, p. 784,788 (1957)
Decarboxylation of Oleic Acid to Heptadecane over Pt Supported on Zeolite 5A Beads
Yang, Liqiu,Tate, Kirby L.,Jasinski, Jacek B.,Carreon, Moises A.
, p. 6497 - 6502 (2015)
The synthesis of Pt supported on zeolite 5A beads for the decarboxylation of oleic acid to heptadecane is demonstrated. The use of a microporous ZIF-67 crystalline layer on zeolite 5A beads not only improved the heptadecane selectivity but also, most importantly, improved the stability of the resultant catalyst. Heptadecane yields as high as ～81% were observed for the fresh catalysts. The catalysts displayed only low to moderate loss of catalytic activity after two rounds of recycle. To our best knowledge, the catalytic performance of these catalysts is superior to those of the state-of-the-art catalysts at mild reaction conditions. In addition, as compared to powders, beads are much easier to recycle, can be fully recovered, and are more amenable for potential scale-up. The resultant catalysts are promising for the catalytic conversion of fatty acid molecules into gasoline/diesel-range hydrocarbons.
Photo-Initiated Cobalt-Catalyzed Radical Olefin Hydrogenation
Sang, Sier,Unruh, Tobias,Demeshko, Serhiy,Domenianni, Luis I.,van Leest, Nicolaas P.,Marquetand, Philipp,Schneck, Felix,Würtele, Christian,de Zwart, Felix J.,de Bruin, Bas,González, Leticia,V?hringer, Peter,Schneider, Sven
, p. 16978 - 16989 (2021/08/09)
Outer-sphere radical hydrogenation of olefins proceeds via stepwise hydrogen atom transfer (HAT) from transition metal hydride species to the substrate. Typical catalysts exhibit M?H bonds that are either too weak to efficiently activate H2 or too strong to reduce unactivated olefins. This contribution evaluates an alternative approach, that starts from a square-planar cobalt(II) hydride complex. Photoactivation results in Co?H bond homolysis. The three-coordinate cobalt(I) photoproduct binds H2 to give a dihydrogen complex, which is a strong hydrogen atom donor, enabling the stepwise hydrogenation of both styrenes and unactivated aliphatic olefins with H2 via HAT.
Steric and Electronic Effects of Phosphane Additives on the Catalytic Performance of Colloidal Palladium Nanoparticles in the Semi-Hydrogenation of Alkynes
Staiger, Lena,Kratky, Tim,Günther, Sebastian,Tomanek, Ondrej,Zbo?il, Radek,Fischer, Richard W.,Fischer, Roland A.,Cokoja, Mirza
, p. 227 - 234 (2020/10/14)
We report on the influence of phosphanes on the catalytic activity and selectivity of colloidal, tetraoctylammonium bromide (TOAB) stabilised palladium nanoparticles (NPs) in the semi-hydrogenation of alkynes to olefins. Full characterisation of the catalytic system (HRTEM, EDX, XPS, IR, NMR) confirmed the formation of spherical particles with a narrow size distribution (1.9±0.5 nm). The catalytic performance of the Pd NPs in the semi-hydrogenation of 1-octyne, 2-octyne and phenylacetylene to the respective olefins and the influences on the selectivity was investigated. The system shows high activities and selectivities at mild conditions (0 °C and 1.0 bar H2 pressure). It was shown that generally, phosphanes lead to an increase of both the reaction rate and selectivity towards the olefin where both steric and electronic effects of the ligand play a crucial role for the catalyst performance. A moderate steric demand of the ligand with a rather weak σ-donating ability turned out to give the highest catalytic performance.
