4461-48-7Relevant academic research and scientific papers
Synthesis of 6-Adamantyl-2-pyridone and Reversible Hydrogen Activation by the Corresponding Bis(perfluorophenyl)borane Complex
Wech, Felix,Müller, Tizian,Becker, Jonathan,Gellrich, Urs
, p. 666 - 672 (2021)
We herein describe the two-step synthesis of 6-Adamantyl-2-pyridone from 1-Acetyladamantane. The borane complex derived from 6-Adamantyl-2-pyridone and the Piers borane liberates dihydrogen at 60 °C. The reverse reaction, hydrogen activation by the formed pyridonate borane is accomplished under mild conditions. The mechanism of the hydrogen activation is studied by DFT computations.
Nickel Hydride Complexes Supported by a Pyrrole-Derived Phosphine Ligand
Collett, Joel D.,Guan, Hairong,Krause, Jeanette A.
, p. 345 - 353 (2022/02/16)
The synthesis of two nickel hydride complexes bearing the pyrrole-derived phosphine ligand CyPNH (2-(dicyclohexylphosphino)methyl-1H-pyrrole) was developed, namely, (κP-CyPNH)(κP,κN-CyPN)NiH and the acid-stable trans-(κP-CyPNH)2Ni(OAc)H·HOAc. (κP-CyPNH)(κP,κN-CyPN)NiH stoichiometrically reduces benzaldehyde and acetophenone in a metal-ligand cooperative manner and catalytically dimerizes ethylene and cycloisomerizes 1,5-cyclooctadiene and 1,5-hexadiene. trans-(κP-CyPNH)2Ni(OAc)H·HOAc, available from the protonation of (κP-CyPNH)(κP,κN-CyPN)NiH with acetic acid, catalyzes the cycloisomerization of 1,5-cyclooctadiene more effectively and produces the less thermodynamically favored cycloisomers of 1,5-cyclooctadiene.
Merging Halogen-Atom Transfer (XAT) and Cobalt Catalysis to Override E2-Selectivity in the Elimination of Alkyl Halides: A Mild Route towardcontra-Thermodynamic Olefins
Zhao, Huaibo,McMillan, Alastair J.,Constantin, Timothée,Mykura, Rory C.,Juliá, Fabio,Leonori, Daniele
supporting information, p. 14806 - 14813 (2021/09/18)
We report here a mechanistically distinct tactic to carry E2-type eliminations on alkyl halides. This strategy exploits the interplay of α-aminoalkyl radical-mediated halogen-atom transfer (XAT) with desaturative cobalt catalysis. The methodology is high-yielding, tolerates many functionalities, and was used to access industrially relevant materials. In contrast to thermal E2 eliminations where unsymmetrical substrates give regioisomeric mixtures, this approach enables, by fine-tuning of the electronic and steric properties of the cobalt catalyst, to obtain high olefin positional selectivity. This unprecedented mechanistic feature has allowed access tocontra-thermodynamic olefins, elusive by E2 eliminations.
METHOD OF PRODUCING TERMINAL DOUBLE BOND-CONTAINING COMPOUND
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Paragraph 0044-0048, (2020/10/09)
SOLUTION: A method of producing a terminal double bond-containing compound includes: reacting a compound represented by the following general formula (I) under a pressure of 0 MPa-G or lower in the presence of a metal oxide catalyst to produce a terminal double bond-containing compound represented by the following general formula (II). In formula (I) and formula (II), R1 and R2 represent hydrocarbon groups, and R1 and R2 may bond each other to form a ring together with carbon atoms by which R1 and R2 bond. EFFECT: According to the present invention, a terminal double bond-containing compound can be safely and easily produced with high selectivity. SELECTED DRAWING: None COPYRIGHT: (C)2020,JPOandINPIT
Olefin oligomerization via new and efficient Br?nsted acidic ionic liquid catalyst systems
Wang, Guoqin,Song, Heyuan,Li, Ruiyun,Li, Zhen,Chen, Jing
, p. 1110 - 1120 (2018/05/28)
Olefin oligomerization reaction catalyzed by new catalyst systems (a Br?nsted-acidic ionic liquid as the main catalyst and tricaprylylmethylammonium chloride as the co-catalyst) has been investigated. The synthesized Br?nsted acidic ionic liquids were characterized by Fourier transform infrared spectroscopy (FT-IR), ultraviolet-visible spectroscopy (UV), 1H nuclear magnetic resonance (NMR), and 13C NMR to analyze their structures and acidities. The influence of different ionic liquids, ionic liquid loading, different co-catalysts, catalyst ratios (mole ratio of ionic liquid to co-catalyst), reaction time, pressure, temperature, solvent, source of reactants, and the recycling of catalyst systems was studied. Among the synthesized ionic liquids, 1-(4-sulfonic acid)butyl-3-hexylimidazolium hydrogen sulfate ([HIMBs]HSO4) exhibited the best catalytic activity under the tested reaction conditions. The conversion of isobutene and selectivity of trimers were 83.21% and 35.80%, respectively, at the optimum reaction conditions. Furthermore, the catalyst system can be easily separated and reused; a feasible reaction mechanism is proposed on the basis of the distribution of experimental products.
METHOD FOR PRODUCING 4-METHYL-1-PENTENE
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Paragraph 0024, (2018/05/05)
PROBLEM TO BE SOLVED: To provide a method for producing 4-methyl-1-pentene that can inhibit the by-production of olefins other than 4-methyl-1-pentene and is relatively safe. SOLUTION: A method for producing 4-methyl-1-pentene includes the step of dehydrating 4-methyl-1-pentanol in the presence of a solid acid catalyst. SELECTED DRAWING: None COPYRIGHT: (C)2018,JPOandINPIT
Selective Dimerization of Propylene with Ni-MFU-4l
Comito, Robert J.,Metzger, Eric D.,Wu, Zhenwei,Zhang, Guanghui,Hendon, Christopher H.,Miller, Jeffrey T.,Dinc?, Mircea
supporting information, p. 1681 - 1683 (2017/05/15)
We report the selective dimerization of propylene to branched hexenes using Ni-MFU-4l, a solid catalyst prepared by cation exchange. Analysis of the resulting product distribution demonstrates that the selectivity arises from 2,1-insertion and slow product reinsertion, mechanistic features reproduced by a molecular nickel tris-pyrazolylborate catalyst. Characterization of Ni-MFU-4l by X-ray absorption spectroscopy provides evidence for discrete, tris-pyrazolylborate-like coordination of nickel, underscoring the small-molecule analogy that can be made at metal-organic framework nodes.
Hydrogenation of ketones over bifunctional Pt-heteropoly acid catalyst in the gas phase
Alharbi,Kozhevnikova,Kozhevnikov
, p. 457 - 462 (2015/10/05)
Gas-phase hydrogenation of a wide range of ketones to alkanes, including hydrogenation of aliphatic ketones and acetophenone, was investigated using bifunctional metal-acid catalysis. The catalysts were comprised of a metal (Pt, Ru, Ni, and Cu) supported on acidic caesium salt of tungstophosphoric heteropoly acid Cs2.5H0.5PW12O40 (CsPW). The reaction occurred via a sequence of steps involving hydrogenation of ketone to alcohol on metal sites followed by dehydration of alcohol to alkene on acid sites and finally hydrogenation of alkene to alkane on metal sites. Catalyst activity decreased in the order: Pt > Ru >> Ni > Cu. Pt/CsPW showed the highest catalytic activity, giving almost 100% alkane yield at 100 °C and 1 bar pressure. Evidence is provided that the reaction with Pt/CsPW at 100 °C is limited by ketone-to-alcohol hydrogenation, whereas at lower temperatures (≤60 °C) by alcohol dehydration yielding alcohol as themain product. The catalyst comprised of a physical mixture of Pt/C + CsPW was found to be highly efficientas well, which indicates that the reaction is not limited by migration of intermediates between metal andacid sites in the bifunctional catalyst.
Ethylene-bridged C1-symmetric ansa-(3-R-indenyl)(fluorenyl) zirconocene complexes for propylene dimerization or polymerization: The effect of R group
Wang, Yan,Huang, Wenzhong,Ma, Haiyan,Huang, Jiling
, p. 81 - 93 (2014/05/06)
A series of ethylene-bridged C1-symmetric ansa-(3-R-indenyl) (fluorenyl) zirconocene complexes 3a-i (R = 2-[2-(4-methylphenyl)propyl], 3a; R = 2-[2-(3,5-dimethylphenyl)propyl], 3b; R = 2-(2-benzylpropyl), 3c; R = 2-methylbenzyl, 3d; R = 2-(2-cyclohexylpropyl), 3e; R = 2-[2-(1-cyclohexenyl) propyl], 3f; R = 2-(2-n-butylpropyl), 3g; R = cyclohexyl, 3h; R = iPr, 3i) were synthesized by a salt metathesis method and characterized by NMR spectroscopy, elemental analysis (or HRMS) and X-ray diffraction (3e and 3h). Upon activation with methylaluminoxane, most of these zirconocene complexes exhibited sufficient catalytic activities up to 2.5 × 105 g C6/(mol-Zr·h) and high selectivities up to 99% toward propylene dimerization, affording 2-methyl-1-pentene as the major isomer which was confirmed by gas chromatography. Remarkably, the selectivity and activity of complexes 3a-i were significantly influenced by the structural features of the substituent on the 3-position of indenyl ring: a pendant aryl or alkyl group linked by a quaternary carbon bridge provided the complex with high selectivities in the range of 89.9-99.0% for 2-methyl-1-pentene and low to moderate catalytic activities; the lack of a quaternary carbon bridge within the substituent would lead to mainly polypropylenes of low molecular weight. The steric hindrance around the active metal center induced by the pendant group might be responsible for the catalytic dimerization behavior, and the presumed mechanism was discussed. In addition, for complexes 3h and 3i, the selectivity for propylene dimerization could also be enhanced with the increase of reaction temperature. Noticeably, most of these ansa-zirconocene complexes exhibit excellent thermal stability at 100 °C, which is important with regard to industrial application. 2014 Elsevier Ltd. All rights reserved.
SELECTIVE DEHYDRATION OF ALCOHOLS TO DIALKYLETHERS AND INTEGRATED ALCOHOL-TO-GASOLINE PROCESSES
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Paragraph 0045, (2013/04/24)
The invention involves an integrated process for converting a C1-C4 alcohol to gasoline and/or diesel boiling tinge product, said process comprising: contacting a C1-C4 alcohol feed under selectively dehydrating conditions with a catalyst comprising γ-alumina which is substantially free of terminal hydroxyl groups on tetrahedrally coordinated aluminum sites of the catalyst to form a dialkylether dehydration product; and contacting the dialkylether dehydration product with a zeolite conversion catalyst under conversion conditions to form the gasoline and/or diesel boiling range hydrocarbon product.
