- Ferrocenylalanes: Solid-state and solution structures of some new aluminum-bridged ansa-ferrocenes
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Addition of dilithiated ferrocene to AlEt2Cl and Al(κ2-C, NNMe2CH2C6H 4)Cl2 yields the trimeric ferrocenyl derivative 1 and the dimeric [1,1′]-ferrocenophane 2, respectively. Sol
- Braunschweig, Holger,Burschka, Christian,Clentsmith, Guy K. B.,Kupfer, Thomas,Radacki, Krzysztof
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- Trialkylaluminum N-Heterocyclic Olefin (NHO) Adducts as Catalysts for the Polymerization of Michael-Type Monomers
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The synthesis of new trialkylaluminum adducts with N-heterocyclic olefin (NHO) ligands is described. These well-defined complexes can catalyze the polymerization of various Michael-type monomers, such as 2-vinylpyridine, methylacrylate, and dimethylacryla
- Watson, Ian C.,Zhou, Yuqiao,Ferguson, Michael J.,Kr?nzlein, Moritz,Rieger, Bernhard,Rivard, Eric
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supporting information
p. 547 - 551
(2020/02/20)
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- Process for synthesis of triethyl (by machine translation)
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The invention discloses a process for synthesis of triethyl, comprising the following steps: the percentage pondere the aluminum powder and titanium powder mixed, under the protection of inert gas, is added to the aluminum is provided with three reaction kettle as seed, in 120-130 °C and 8-12MPa under the reaction conditions, to carry out hydrogenation reaction 6-7 hours, in 0.2-0.3 MPa pressure of the ethylene is injected continuously in the reaction kettle, 5-6 hours to get crude reaction is completed within three b aluminum, product through distillation, ethylene purification of final products. This invention, in order to triethyl aluminum seed material as the main body of a dispersion medium catalytic reaction, the reaction temperature and the pressure is low, the yield of the obtained product can reach 90% or more. (by machine translation)
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Paragraph 0010
(2016/11/21)
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- The synthesis and deep purification of GaEt3. Reversible complexation of adducts MAlk3 (M = Al, Ga, In; Alk = Me, Et) with phenylphosphines
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Optimal parameters of organomagnesium technique of synthesis of triethylgallium have been defined. Various techniques of deep purification of triethylgallium to the extent required in metalorganic vapor-phase epitaxy MOVPE have been studied: by way of residue ether displacement through high-performance rectification and interaction with high pure aluminum and gallium trichloride, and by way of reversible complexation with triphenylphosphine, 1,3-bis(diphenylphosphine)propane and 1,5- bis(diphenylphosphine)pentane. Advantages and disadvantages of each technique have been identified. We have shown high performance of adduct purification technique covering trimethyl and triethyl derivatives of aluminum, gallium and indium. The structure of donor-acceptor complexes between metal alkyls and the above-mentioned phosphines have been verified using H and 31P NMR spectroscopy and X-ray studies, as well as quantum chemical calculations. Thermal stability of triethylgallium and oxidation of its adducts with phosphines have been studied.
- Shatunov,Korlyukov,Lebedev,Sheludyakov,Kozyrkin,Orlov, V.Yu.
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p. 2238 - 2251
(2011/06/22)
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- Synthesis of trialkylaluminum derivatives by the reaction of non-solvated aluminum hydride with α-olefins
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Hydroalumination of α-olefins by non-solvated polymeric aluminum hydride (AlH3)n occurs at 120-140°C. Mechanochemical activation accelerates this reaction. The addition of catalytic amounts of the prepared R3Al forms to the reaction system decreases the temperature of the process to 90-100°C. The greatest initiation effect is observed when ate-complexes of the MAlR4 type (M = Li, Na) are used: the reaction occurs with a higher rate already at 60-90°C affording R3Al free of admixtures of carbalumination products and dimers of α-olefins.
- Gavrilenko
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p. 1161 - 1163
(2007/10/03)
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- Transition metal compound having indenyl-containing metallocene
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The novel transition metal compound of the invention is represented by the following formula (I): STR1 wherein M is a transition metal; R1 is a hydrocarbon group of 2 to 6 carbon atoms, R2 is an aryl group of 6 to 16 carbon atoms; X1 and X2 are each a halogen atom or the like; and Y is a divalent hydrocarbon group, a divalent silicon-containing group or the like. An olefin polymerization catalyst component of the present invention comprises the aforementioned transition metal compound.
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- Hydrocarbon solutions of alkylaluminoxane compounds
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A hydrocarbon solvent solution of alkylaluminoxane comprises a hydrocarbon solvent having dissolved therein methylaluminoxane and an effective amount to solubilize the methylaluminoxane in the solvent of a tri-n-alkylaluminum wherein the alkyl groups each contain at least two carbon atoms.
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- Interaction of trialkylaluminum reagents with metal-bound ethylene and carbon monoxide. The molecular structure of (η5-C5Me5)2Ta(H)(C 2H4·AlEt3)
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The compounds (η5-C5Me6)2M(H) (C2H4) and (η5-C5Me5)2M(H)(CO) (M = Nb, Ta) reversibly bind trialkylaluminum reagents to give 1:1 adducts in which the aluminum is bonded to the metal-bound ethylene or carbonyl oxygen in preference to the hydride ligand. The mixed-ring compound (η5-C5Me5) (η5-C5H5)Ta(H)(CO), in contrast, binds aluminum at the hydride ligand. The nature of the interactions has been established by IR and NMR studies and by determination of the molecular structure of (η5-C5Me5)2Ta(H)(C 2H4·AlEt38) at reduced temperature [P21/c, a = 14.877 (5) A?, b = 12.455 (7) A?, c = 15.017 (4) A?, β = 101.08 (13)°, V = 2730 (2) A?3, T = 220 K, Z = 4, 2496 reflections, S (goodness-of-fit) = 2.75, 283 parameters, R = 0.054 (2033 reflections, I > 3σI)]. This structure displays an unusual ethylene bridge between the aluminum and tantalum centers. The significance of these adducts in the context of Ziegler-Natta catalysis and migratory insertion is discussed.
- McDade, Christine,Gibson, Vernon C.,Santarsiero, Bernard D.,Bercaw, John E.
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- 37Al NMR spectroscopy of triethylaluminum. A direct method to the determination of the proportion of monomer in solution
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The sole 27Al NMR signal of triethylaluminum (TEA) is shifted significantly to lower field with: (1) decreasing concentration; (2) increasing temperature; and (3) increasing polarity of the solvent; that is, in each case with an increase in the amount of the monomeric form. 27Al NMR chemical shifts of Al2Et6 and AlEt3 are estimated as 153 +/- 2 and 265 +/- 10 ppm, respectively.By use of these and observed values, thermodynamic data Kd, ΔHd and ΔSd were calculated for the dissociation of Al2Et6.The dependence of the monomer-dimer equilibria on the concentration of TEA in the solvents used indicated the participation of an intermolecular process in the exchange of bridging and terminal ethyl groups not only in aromatic solvents but also, in contrast to previous reports, in aliphatic hydrocarbons.
- Cerny, Z.,Hermanek, S.,Fusek, J.,Kriz, O.,Casensky, B.
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- Aluminum Dichloride and Dibromide. Preparation, Spectroscopic (Including Matrix Isolation) Study, Reactions, and Role (Together with Alkyl(aryl)aluminum Monohalides) in the Preparation of Organoaluminum Compounds
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Anhydrous aluminum trichloride or bromide when heated in a 2:1 molar ratio with aluminum powder as a suspension in dry n-heptane or methylcyclohexane was found to be partially reduced to aluminum dichloride or dibromide.Ultrasound treatment (sonication) significantly promotes the reaction.Aluminum dichloride in higher purity was obtained by the reaction of the gaseous aluminum trichloride with aluminum metal in a high-vacuum reactor, allowing subsequent investigation by IR spectroscopy.An aluminum sub-halide of the form Al2(i-Bu)4-xClx was also prepared through the reaction of the tetraisobutyldialane and HCl at room temperature.Both materials were investigated by IR spectroscopy and compared to AlCl2 prepared and isolated through the codeposition of aluminum atom and molecular chlorine in a solid argon matrix.The matrix study characterized AlCl2 together with AlCl and AlCl3, which were also formed in the system.The paramagnetic aluminum dihalides, i.e.AlCl2 and AlBr2, are associated in the condensed state (except under matrix isolation conditions where they are monomeric).An ESR study of the pyridinium complex of AlCl2 was carried out and showed its paramagnetic nature.In the present study, for simplicity, the reactions of the aluminum dihalide are considered as those of the dimers but could involve higher associated oligomers.MNDO calculation on the heats of formation of several possible isomeric structures of Al2Cl4 indicate the preference for both halogen bridging and significant Al-Al bonding in the dimer.Reaction of AlCl3 + Al with ethylene, the Hall and Nash reaction, was reinvestigated by 13C and 27Al NMR spectroscopy.The reaction was found to give, besides ethylaluminum sesquichloride, 1,2- and 1,1-bis(dichloroaluminio)ethanes.Cyclohexene in a similar reaction gives although less readily, 1,2-bis(dichloroaluminio)cyclohexane.The reaction are indicative of addition of (AlCl2)2 to the olefins.Aklyl- and arylaluminum monohalides are intermediately formed in the reaction of alkyl halides or halobenzenes with active aluminum powder.These divalent aluminum halides are also considered to be dimeric in nature and immediately react with excess of the alkyl (aryl) halides to form the corresponding sesquihalides.In contrast, aluminum dihalides formed in the aluminum trihalide-aluminum metal systems react with alkyl or aryl halides to give alkyl(aryl)aluminum dihalides.Sonication was found to significantly promote these reactions.
- Olah, George A.,Farooq, Omar,Farnia, S. Morteza F.,Bruce, Mark R.,Clouet, Francoise L.,et. al.
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p. 3231 - 3238
(2007/10/02)
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- Variable-temperature NMR study of dynamic exchange in sodium (μ-fluoro)bis(triethylaluminate)
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Variable-temperature 13C studies and 1H and 27Al NMR studies have been carried out on mixtures of Na[Al2Et6F] and Al2Et6. We observe that Na[Al2Et6F] undergoes facile exchange of AlEt3 with Al2Et6 in contrast to previously published work. The exchange process has been shown to involve a dissociative mechanism. A ΔH?of 20.4 kcal mol-1 (85.4 kJ mol-1) and ΔS? of 18.7 eu were determined. The value of ΔH? closely approximates the bond dissociation energy for the Al-F bond in Et3Al-F-AlEt3. This is the first reported bond dissociation energy for the Al-F bond in this unusual class of compounds.
- Harrison, James J.,Beach, David L.,Young, Donald C.,Seshadri, Kalkunte S.,Nelligan, John D.
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p. 343 - 346
(2008/10/08)
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