110-71-4Relevant articles and documents
EFFECT OF MODIFIED ADDITIVES ON THE SELECTIVITY OF TRANSFORMATION OF METHANOL INTO AROMATIC HYDROCARBONS OR LOWER OLEFINS IN THE PRESENCE OF PENTASILS
Vasina, T. V.,Isaev, S. A.,Preobrazhenskii, A. V.,Rostanin, N. N.,Konoval'chikov, L. D.,et al.
, (1987)
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CONVERSION OF METHANOL INTO HYDROCARBONS IN THE PRESENCE OF MODIFIED HIGH-SILICON ZEOLITE CATALYSTS
Vasina, T. D.,Khelkovskaya-Sergeeva, E. G.,Rostanin, N. N.,Konoval'chikov, B. K.,Nefedov, B. K.,Bragin, O. V.
, p. 1347 - 1351 (1986)
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Niobia-modified aluminas prepared by impregnation with niobium peroxo complexes for dimethyl ether production
Rocha, Angela S.,Da S. Forrester, Aline M.,Lachter, Elizabeth R.,Faro Jr., Arnaldo C.,Sousa-Aguiar, Eduardo F.
, p. 104 - 111,8 (2012)
Use of a water-soluble niobium peroxo complex allowed the preparation of niobium-modified aluminas containing up to 90% of the theoretical niobia monolayer in one impregnation step. There was a maximum in the density of surface Lewis acid sites at 45% of the theoretical monolayer. FTIR of adsorbed pyridine and adsorbed CO2 suggest the vertical growth of the Nb 2O5 layer for the largest niobium contents. The addition of 22.5% of the theoretical monolayer eliminated about 80% of the basic surface hydroxyls, inhibiting the adsorption of gas phase CO2 by the samples. The niobia/alumina catalysts suffered less inhibition by CO2 than the pure alumina in the methanol dehydration reaction, confirming that Nb 2O5 is mainly deposited on sites where the CO2 adsorption is stronger, leaving free sites that are active in catalytic dehydration and less inhibited by CO2, however none of the niobia/aluminas was more active than the pure alumina. Nevertheless, in the direct syngas to DME conversion using a mixed catalyst system comprised of a CuZnAl methanol synthesis catalyst and a methanol dehydration component, the activity was significantly larger with a niobia/alumina as a dehydrating component than with the pure alumina.
Carbonylation of methanol to acetic acid using homogeneous Ru complex catalyst
Kelkar, Ashutosh A.,Kolhe, Devidas S.,Chaudhari, Raghunath V.
, p. 111 - 116 (1992)
Carbonylation of methanol to give acetic acid catalysed by Ru complexes such as trans-Ru(CO)2Cl2(PPh3)2, cis-Ru(CO)2Cl2(PPh3)2 and H2Ru(CO)(PPh3)3 is reported.The highest activity and selectivity were obtained with H2Ru(CO)(PPh3)3 as the catalyst precursor.Hydrogen increases the activity and selectivity of catalysts such as trans-Ru(CO)2Cl2(PPh3)2, cis-Ru(CO)2Cl2(PPh3)2, but has no influence on the activity and selectivity in the case of H2Ru(CO)(PPh3)3.
Marcus,Darwent,Steacie
, p. 993 (1948)
C-C Bond Formation from Dimethil Ether via a Radical Mechanism in the Presence of Strong Acid
Choukroun, Henri,Brunel, Daniel,Germain, Alain
, p. 6 - 7 (1986)
The selective radical dimerization of dimethyl ether by peroxodisulphuryl difluoride in fluorosulphuric acid, suggests that a radical intermediate for initial C-C bond formation in the conversion of methanol into hydrocarbons is a possibility.
Visualizing Element Migration over Bifunctional Metal-Zeolite Catalysts and its Impact on Catalysis
Cheng, Kang,Wang, Genyuan,Wang, Ye,Wang, Yuhao,Zhang, Qinghong,de Jong, Krijn P.,van der Wal, Lars I.
, p. 17735 - 17743 (2021)
The catalytic performance of composite catalysts is not only affected by the physicochemical properties of each component, but also the proximity and interaction between them. Herein, we employ four representative oxides (In2O3, ZnO, Cr2O3, and ZrO2) to combine with H-ZSM-5 for the hydrogenation of CO2 to hydrocarbons directed by methanol intermediate and clarify the correlation between metal migration and the catalytic performance. The migration of metals to zeolite driven by the harsh reaction conditions can be visualized by electron microscopy, meanwhile, the change of zeolite acidity is also carefully characterized. The protonic sites of H-ZSM-5 are neutralized by mobile indium and zinc species via a solid ion-exchange mechanism, resulting in a drastic decrease of C2+ hydrocarbon products over In2O3/H-ZSM-5 and ZnO/H-ZSM-5. While, the thermomigration ability of chromium and zirconium species is not significant, endowing Cr2O3/H-ZSM-5 and ZrO2/H-ZSM-5 catalysts with high selectivity of C2+ hydrocarbons.
Synthesis, characterization and molecular structures of barium(II) trichloroacetate DME/1,4-dioxane compounds
Singh, Sukhjinder,Saini, Deepika,Mehta,Kaur, Ravneet,Ferretti, Valeria
, p. 202 - 209 (2012)
Two new barium(II) trichloroacetate compounds, [Ba(H2O)(DME) (μ-O2CCCl3)2]n (1) and [{Ba(H2O)2(diox)0.5(μ-O2CCCl 3)2}(diox)]n (2) were synthesized and characterized by elemental analyses, physiochemical studies, FT-IR, 1H NMR, thermogravimetric analyses (TG/DTG/DSC) and single crystal X-ray studies. The reaction of hydrated barium(II) trichloroacetate monohydrate with excess DME (1,2-dimethoxyethane) and diox (1,4-dioxane) in methanol at room temperature led to the isolation of the novel compounds 1 and 2, respectively. Bridging trichloroacetate groups are anticipated on the basis of FT-IR studies and this was confirmed by the X-ray studies. Both compounds dissociate to produce ions in water, as shown by molar conductance values. 1H NMR spectroscopy confirms that DME and 1,4-dioxane are coordinated to the metal ion in these compounds. Single crystal X-ray diffraction studies reveal that the barium cation is coordinated to nine O atoms in a deformed coordination polyhedron in both compounds. Structural data of barium(II) trichloroacetates compounds have been obtained for the first time in the present investigation.
The Ionic Hydrogen Bond. 2. Multiple NH+...O and CH?+...O Bonds. Complexes of Ammonium Ions with Polyethers and Crown Ethers
Meot-Ner (Mautner), Michael
, p. 4912 - 4915 (1983)
Complexes of ammonium ions RNH3+ (R = CH3, c-C6H11), (CH3)3NH+, and pyridineH+ with polyethers and crown ethers are observed in the gas phase in the abscence of the solvent effects.The dissociation energies, ΔH0D, of the RNH3+ polyether complexes range from 29.4 kcal mol-1 (for RNH3+*CH3OCH2CH2OCH3) to 46 kcal mol-1 (RNH3+*18-crown-6).The large ΔH0D values for complexes of polydentate ligands indicate multiple -NH+...O-hydrogen bonding.Such mutiple bonding can contribute up to 18 kcal mol-1 to the bonding in RNH3+*CH3(OCH2CH2)3OCH3 and 21 kcal mol-1 in RNH3+*18-crown-6.Multiple interactions are also evident in the (CH3)3NH+*polyether complexes where -CH?+...O-hydrogen bonding seems to occur; and consecutive -CH?+...O-bonds contribute approximately 6, 4, and 2 kcal/mol-1 respectively for up to three such bonds.Total ΔH0D values in the (CH3)3NH+*polyether complexes thus range from 26.7 kcal mol-1 in (CH3)3NH+*CH3O(CH2)2OCH3 to 41 kcal mol-1 in (CH3)3NH+*18-crown-6.Multiple interaction effects, possibly including van der Waals dispersion forces, are observed also in pyridineH+*polyether complexes.Large negative entropies in RNH3+*acyclic polyether complexes vs.RNH3+*cyclic crown ethers make the acyclic polyethers less efficient ligands.
Alkali Metal Adducts of an Iron(0) Complex and Their Synergistic FLP-Type Activation of Aliphatic C-X Bonds
Tinnermann, Hendrik,Sung, Simon,Csókás, Dániel,Toh, Zhi Hao,Fraser, Craig,Young, Rowan D.
supporting information, p. 10700 - 10708 (2021/07/31)
We report the formation and full characterization of weak adducts between Li+ and Na+ cations and a neutral iron(0) complex, [Fe(CO)3(PMe3)2] (1), supported by weakly coordinating [BArF20] anions, [1·M][BArF20] (M = Li, Na). The adducts are found to synergistically activate aliphatic C-X bonds (X = F, Cl, Br, I, OMs, OTf), leading to the formation of iron(II) organyl compounds of the type [FeR(CO)3(PMe3)2][BArF20], of which several were isolated and fully characterized. Stoichiometric reactions with the resulting iron(II) organyl compounds show that this system can be utilized for homocoupling and cross-coupling reactions and the formation of new C-E bonds (E = C, H, O, N, S). Further, we utilize [1·M][BArF20] as a catalyst in a simple hydrodehalogenation reaction under mild conditions to showcase its potential use in catalytic reactions. Finally, the mechanism of activation is probed using DFT and kinetic experiments that reveal that the alkali metal and iron(0) center cooperate to cleave C-X via a mechanism closely related to intramolecular FLP activation.
PROCESSES FOR FORMING GLYCOLS
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Paragraph 0096, (2020/05/28)
This disclosure provides processes for forming glycols by upgrading hydrocarbons. In one embodiment, a process for forming a glycol includes introducing a first ether to a dihydrocarbyl peroxide to form a diether and a first alcohol. The process includes introducing the diether to water to form a glycol and a second alcohol. Processes of this disclosure may include one or more of: introducing a hydrocarbyl hydroperoxide to a third alcohol to form the dihydrocarbyl peroxide; oxidizing a first feed stream comprising a branched hydrocarbon to form the hydrocarbyl hydroperoxide and the first alcohol; and/or introducing the second alcohol to a catalyst to form a second ether.
