513-35-9Relevant articles and documents
Abe,Shobayashi
, (1929)
Tert-amyl methyl ether (TAME). Thermodynamic analysis of reaction equilibria in the liquid phase
Datta,Egleston,Syed
, p. 319 - 323 (2000)
Ethers obtained from C5 olefin streams provide a good mix of octane-enhancing and CO-reducing qualities. They are considered as a replacement for the more common isobutylene-derived fuel additives, e.g., MTBE. Data on the thermodynamic reaction equilibria for the synthesis of TAME, which is produced from the etherification reaction of 2-methyl-1-butylene and 2-methyl-2-butylene with methanol, were computed by studying TAME decomposition in a recirculating batch reactor at different temperatures with activity coefficients obtained using the UNIFAC method. A comparison of experimental data and theoretical predictions showed the possibility of erroneous values reported in the literature for the standard Gibbs free energy of TAME formation. Expressions for the thermodynamic equilibrium constants as a function of temperature were developed. A corrected value for the Gibbs free energy of formation for TAME was also provided.
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Shapiro,Swinbourne
, p. 465 (1967)
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Duncan,Cvetanovic
, p. 3593 (1962)
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DEHYDRATION OF 2-METHYL-2-BUTANOL ON ZEOLITES
Maksimov, A. I.,Levitskii, I. I.,Minachev, Kh. M.
, p. 2275 - 2278 (1981)
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Novel synthesis of isoprene from 3-methylbutan-2-one using phosphate catalysts
Hutchings, Graham J.,Hudson, Ian D.,Bethell, Donald,Timms, Don G.
, p. 1489 - 1490 (1999)
AlPO4 and BPO4 catalyse the conversion of 3-methylbutan-2-one to isoprene in high yields via 2-methylbut-2-en-1-ol as an intermediate.
Mitsutomi
, p. 1693 (1961)
Kinetics of the Thermal Isomerization of 1,1-Dimethylcyclopropane
Kalra, Bansi L.,Lewis, David K.
, p. 853 - 858 (2001)
Rate constants for the unimolecular thermal isomerization of gaseous 1,1-dimethylcyclopropane to isomeric methylbutenes have been measured, and Arrhenius parameters determined, over a wide temperature range, 683 - 1132 K, using a single-pulse shock tube and a static reactor. For the overall reaction, Ea = 61.8 +/- 0.4 kcal/mol, and log10(A, s-1) = 15.04 +/- 0.10. These values are in good agreement with previously reported values obtained over a much narrower temperature range. Rate constants for formation of the two major products, 2-methylbut-2-ene and 3-methylbut-1-ene, are given by Ea = 61.9 kcal/mol, logA = 14.80 and Ea = 61.1 kcal/mol, logA = 14.54, respectively. A comparison of the activation parameters for structural isomerizations of cyclopropane, methylcyclopropane, and 1,1-dimethylcyclopropane confirms a trend toward lower activation energy values as hydrogen atoms in cyclopropane are replaced by CH3 groups.
Enthalpy of combustion and enthalpy of vaporization of 2-ethyl-2-methoxypropane and thermodynamics of its gas-phase synthesis from (methanol + a 2-methylbutene)
Rozhnov, A. M.,Safronov, V. V.,Verevkin, S. P.,Sharonov, K. G.,Alenin, V. I.
, p. 629 - 635 (1991)
Equilibrium constants the gas-phase synthesis reaction of 2-ethyl-2-methoxypropane (EMOP) from methanol and a 2-methylbutene have been found at the temperatures: 373 K, 399 K, and 413 K.The molar enthalpy of combustion was determined calorimetrically. ΔvapHmdeg(298.15 K) = (35.3 +/- 1.5) kJ * mol-1 and ΔfHmdeg(298.15 K, g) = -(305.4 +/- 1.8) kJ * mol-1 were found for EMOP both on the basis of the results obtained in the present work and literature values.
Catalytic dehydrogenation of isopentane with iridium catalysts
Alt, Helmut G.,Boehmer, Ingrid K.
, p. 2619 - 2621 (2008)
(Graph Presented) Activation by adding PPh3: The catalytic dehydrogenation of isopentane to give isopentene and hydrogen with iridium catalysts ona silica gel support at 450°C proceeds with impressive conversion whenthe support is impregnated w
Hexaruthenium carbido carbonyl methyl cluster as catalyst precursor for hydrogenation of olefins. Syntheses and structures of unsaturated and saturated hexaruthenium hydrido clusters and
Chihara, T.,Yamazaki, H.
, p. 273 - 284 (1994)
Cluster (2) has been found to be catalytic active for the hydrogenation and isomerization of olefins at 60 deg C after an induction period.Reaction of 2 or with dihydrogen at 130 deg C gives an unsaturated hydrido cluster (6), which behaves as the catalyst at ambient temperature.The structure of 6 has a carbon-centered octahedral geometry of ruthenium atoms which is surrounded by fifteen carbonyl ligands, two terminal ones for each ruthenium atom and three bridging ones, and a bridging hydrido ligand.Treatment of 6 with carbon monoxide yields a saturated hydrido cluster (5), which is also prepared by protonation of 2.X-ray analysis of 5 shows the cluster anion is disordered between two sites in the ratio of 8 to 2.The major one contains a carbon centered octahedron of six ruthenium atoms with two terminal carbonyl ligands for each ruthenium atom, with four bridging carbonyl ligands, and a terminal hydrido ligand. Key words: Ruthenium; Carbide; Carbonyl; Cluster; Catalyst precursor
Sorption, acid, and catalytic properties of a sulfonic cation exchanger supported on the carbon fiber
Egiazarov,Shachenkova,Radkevich,Cherches,Gorbatsevich,Ermolenko
, p. 1761 - 1764 (2004)
Distribution in strength of the acid centers in sulfonic cation in the form of exchanger granules and fibers was studied by the novel modification of the thermal desorption method.
Homogeneous Unimolecular Gas-Phase Elimination Kinetics of 2-Chloro-2-alkylpropanes. The Electronic Effect of Alkyl Substituents on the α-Carbon of Tertiary Chlorides
Chuchani, Gabriel,Martin, Ignacio
, p. 3188 - 3190 (1980)
The pyrolysis kinetics of 2-chloro-2-methylbutane and 2-chloro-2,3-dimethylbutane have been investigated, in a static system and seasoned vessel, over the pressure range of 50-280 torr and the temperature range of 260-320 deg C.The reactions are homogeneous and unimolecular, follow a first-order law, and are invariable to the presence of a cyclohexene inhibitor.The temperature dependence of the rate coefficients is given by the following Arrhenius equations: for 2-chloro-2-methylbutane, logk1 (s-1)=(13.77 +/- 0.25)-(184.1 +/- 2.6) kJ mol-1 (2.303RT)-1; for 2-chloro-2,3-dimethylbutane, logk1(s-1)=(13.33 +/- 0.18)-(175.3 +/- 1.9) kJ mol-1 (2.303RT)-1.The distribution of the olefin products from these reactions has been quantitatively determined and reported in details.The alkyl series ((CH3)3C, (CH3)2CH, CH3CH2, CH3, and H) in the tertiary halides, 2-chloro-2-alkylpropanes, influence the rate of elimination by electronic effect.This is similar to those obtained with α- and β-alkyl-substituted ethyl chlorides.The plot of log k/k0 vs. ?*(R) gives a very good straight line with ρ*=-4.75, r=0.994, and intercept=0.048 at 300 deg C.The previous and present results reveal that, if a reaction center at the transition state of an organic molecule is markedly polar, the +I inductive electron release of alkyl substituents may affect gas-phase elimination processes.
Selectivity patterns in heterogeneously catalyzed hydrogenation of conjugated ene-yne and diene compounds
Bridier, Blaise,Perez-Ramirez, Javier
, p. 165 - 175 (2011)
Selectivity control in heterogeneously catalyzed hydrogenation of conjugated hydrocarbons (ene-yne and diene compounds) is a challenging task. Available studies on the topic mainly encircle 1,3-butadiene as the substrate and palladium as the catalyst, while more elaborated playground molecules and other metals remain largely unexplored. This study investigates the gas-phase hydrogenation of valylene (2-methyl-1-butene-3-yne) and isoprene (2-methyl-1,3-butadiene) over Pd, Pb-poisoned Pd, CO-modified Pd, Cu, Ni, and bimetallic CuNi catalysts. Chemoselectivity, regioselectivity, full hydrogenation, and CC bond formation/scission footprints of the catalytic systems at different inlet hydrogen-to-hydrocarbon ratios and conversion degrees have been rationalized. Complementary studies of 3-methylbutyne and 1-penten-4-yne hydrogenation were carried out in order to analyze (i) the impact of isomerization on the observed mono-olefin distribution in valylene/isoprene hydrogenation and (ii) the conjugation issue in partial ene-yne hydrogenation. Our results lead to an improved understanding of hydrogenation of polyunsaturated hydrocarbons and open doors to design more selective heterogeneous catalysts and related processes for this practically important class of reactions.
A Novel Cationic Optically Active Complex of Platinum(II) Containing 2-Methyl-2-butene and o-Benzenediamine. The Circular Dichroism Spectrum and Kinetics of Olefin Exchange
Miya, Shin'ya,Kashiwabara, Kazuo,Saito, Kazuo
, p. 2309 - 2312 (1981)
An optically active cationic olefin complex, B(C6H5)4 was obtained for the first time as crystal stable in air at room temperature.It deteriorates slightly in solution, but is still stable enough to be characterized.Comparison of its CD spectrum with that of related complexes disclosed that the coordinating atoms at the cis sites to the olefin have a dominant influence upon the CD pattern in the region 20000-35000 cm-1, as compared with those at the trans site.Substitution of cis-1,2-dichloroethylene for the coordinated (S)-2-methyl-2-butene (S-mbn) proceeds in accordance with the second order rate law; there is no contribution of the solvent path.The second order rate constant is smaller than that of trans-.The steric effect of the o-benzenediamine at the transition state seems responsible for the small rate rather than the basicity of the ligand at the trans site to mbn.
Participation of Surface Radical Species with Base Catalytic Activity of Na Metal Doped MgO
Matsuhashi, Hiromi,Arata, Kazushi
, p. 11178 - 11181 (1995)
Participation of F+ centers with the formation of superbase sites was studied.Two kinds of ESR signals were observed with Na metal doped MgO, which was thermally activated at 773, 873, and 973 K.A relationship was found between double bond migration activity of 3-methyl-1-butene and ESR signal intensity which was observed at low magnetic field.This radical species was assigned to an F+ center formed on an unstable MgO surface.The maximum activity was obtained when two electrons were trapped in an anion vacancy.It was concluded that the F+ and F centers played the most important role for the formation of superbase sites.
The study of alkene isomerization catalyzed by the system: Rhodium dimeric complex-tertiary phosphine-tin dichloride
Permin,Petrosyan
, p. 1104 - 1106 (1997)
Rhodium(I) dimeric complexes, [(Ph3P)4Rh2Cl2] and [(C2H4)4Rh2Cl2], form active catalysts for alkenes isomerization on interaction with tertiary phosphine and tin dichloride in CH2Cl2. Besides 2-methylbut-2-ene, which is the normal product of 1,2-double bond migration, 3-methylbut-1-ene gives the product of unusual 1,3-double bond migration, 2-methylbut-1-ene, which is formed at early stages of the reaction under kinetic control in over-equilibrium quantities. The proposed mechanism for 1,3-double bond migration includes the methyl C-H bond activation, followed by intramolecular transfer hydrogenation.
Non-electrophilic Behaviour of Alkyl-substituted Metaphosphates in the Gas Phase: Formation of Alkenes by an Unusual 1,2-Methyl Shift induced by Hydrogen Abstraction-A Methyl Analogue of the Neophyl Ester Rearrangement
Banks, Malcolm R.,Cadogan, J. I. G.,Gosney, Ian,Hodgson, Philip K. G.,Jack, Audrey G. C.,Rodger, David R.
, p. 1033 - 1034 (1989)
Pyrolytic expulsion of ethylene from 2-neopentoxy-1,3,2-dioxaphospholane in the gas phase yields a virtually quantitative mixture of 2-methylbut-1-ene and its more stable isomer, 2-methylbut-2-ene in the ratio 2:1; this can be rationalised, using deuterium-labelling studies, as being formed from a thermally generated metaphosphate by a cyclic, concerted elimination reaction involving, as the key step, an unusual 1,2-methyl shift induced by competing α- and γ-hydrogen abstraction reactions with loss of metaphosphoric acid.
DEHYDRATION OF 3-METHYL-2-BUTANOL ON ZEOLITES
Levitskii, I. I.,Maksimov, A. I.,Mishin, I. V.,Minachev, Kh. M.
, p. 238 - 242 (1987)
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Gorton,Walsh
, p. 782 (1972)
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Catalysis by coke deposits: Synthesis of isoprene over solid catalysts
Ivanova, Irina,Sushkevich, Vitaly L.,Kolyagin, Yury G.,Ordomsky, Vitaly V.
, p. 12961 - 12964 (2013)
A help rather than a hindrance: Carbonaceous deposits have been found to play a key role in the selective synthesis of isoprene from formaldehyde and isobutene over solid catalysts. They accumulate on the catalyst surface during the induction period and promote the interaction of the substrates at the steady state. The proposed mechanism (see scheme) shows the way forward for the design of efficient solid catalysts for the synthesis of isoprene. Copyright
Etherification of tert-amyl alcohol with methanol over ion-exchange resin
Yadav,Joshi
, p. 408 - 414 (2001)
tert-Amyl methyl ether (TAME) is a proven high octane additive. The synthesis of tert-amyl methyl ether from tert-amyl alcohol and methanol has been carried out in the presence of a variety of solid acid catalysts. Amberlyst-36 was found to be very effective in comparison with other solid acids. A complete theoretical and experimental analysis is presented for the model studies of tert-amyl alcohol with methanol. The parallel reactions of tert-amyl alcohol adsorbed on the sites were found to control the overall rate of reaction, which led to the formation of TAME, 2-methyl-1-butene (2MB1), and 2-methyl-2-butene (2MB2). The reaction follows pseudo-first-order kinetics at a fixed catalyst loading. The individual rate constants for the formation of TAME, 2MB1, and 2MB2 were also evaluated from the same data.
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Brown,Moritani
, p. 455 (1954)
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METHOD FOR THE PREPARATION OF A COMPOSITION ENRICHED IN 2-METHYL-BUT-2-ENE AND USE FOR MAKING A POLYMER
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Page/Page column 14, (2021/04/01)
Method for the preparation of a composition enriched in 2-methyl-but-2-ene and use for making a polymer.
CATALYTIC HYDROCARBON DEHYDROGENATION
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Paragraph 0056; 0122; 0123, (2021/03/13)
A catalyst for dehydrogenation of hydrocarbons includes a support including zirconium oxide and Linde type L zeolite (L-zeolite). A concentration of the zirconium oxide in the catalyst is in a range of from 0.1 weight percent (wt. %) to 20 wt. %. The catalyst includes from 5 wt. % to 15 wt. % of an alkali metal or alkaline earth metal. The catalyst includes from 0.1 wt. % to 10 wt. % of tin. The catalyst includes from 0.1 wt. % to 8 wt. % of a platinum group metal. The alkali metal or alkaline earth metal, tin, and platinum group metal are disposed on the support.