3221-61-2Relevant academic research and scientific papers
Chemical and Spectroscopic Studies on Copper Iodide Derived Organocuprates: New Insight into the Composition of Gilman's Reagent
Lipshutz, Bruce H.,Kozlowski, Joseph A.,Breneman, Curt M.
, p. 3197 - 3204 (1985)
Both 1H and 7Li NMR spectroscopy at high field have served to reveal that the addition of ethereal MeLi to MeCu/THF, in the absence of LiI, leads to unprecedented equilibria (Keq ca. 11) between Me2CuLi and MeLi plus Me3Cu2Li.From a series of spectra at -70 degC, a scheme is proposed to account for the signals observed in solutions of varying MeLi:MeCu ratios.These data lead to the conclusion that not only Gilman's reagent but also "Me3CuLi2" and "Me5Cu3Li2" are not discrete, but rather are composed of differing percentages of the same components.In the presence of LiI, or in Et2O solutions alone, however, this equilibrium does not exi sts for MeLi:MeCu ratios up to 1:1.Chemical tests on both ketones and esters, as well as a series of Gilman tests, fully corroborate the existence of various forms of Gilman's reagent.
FURTHER INSIGHT INTO LOWER ORDER CUPRATE CHEMISTRY; ON THE USE OF CuBr*Me2S VS CuI EN ROUTE TO R2CuLi
Lipshutz, Bruce H.,Whitney, Scott,Kozlowski, Joseph A.,Breneman Curt M.
, p. 4273 - 4276 (1986)
Both (1)H and (7)Li NMR experiments show that 2MeLi + either CuBr*Me2S or CuI in THF afford the same species, Me2CuLi (+ LiX).However, use of the former source of Cu(I), depending upon its purity and especially handling, can lead to significantly decreased chemical yields.The reasons behind these observations and the implications for cuprate couplings are discussed.
Insight into decomposition of formic acid to syngas required for Rh-catalyzed hydroformylation of olefins
Liu, Lei,Chen, Xiao-Chao,Yang, Shu-Qing,Yao, Yin-Qing,Lu, Yong,Liu, Ye
, p. 406 - 415 (2020/12/07)
Formic acid (FA) is one kind of important bulk chemicals, which is recognized as a sustainable and eco-friendly energy carrier to transport H2 via dehydrogenation or CO via decarbonylation. Expectantly, FA upon decomposition into H2 and CO could be used as the syngas alternative for hydroformylation. In this paper, the behaviors of FA to release H2 as well as CO following the distinct pathways were carefully investigated for the first time, and then established a new hydroformylation protocol free of syngas. It was found that the atmospheric hydroformylation of olefins with formic acid (FA) as syngas alternative was smoothly fulfilled over Xantphos (L1) modified Rh-catalyst under mild conditions (80 °C, Rh concentration 1 mol %, 14 h), resulting in >90% conversion of the olefins along with the high selectivity to the target aldehydes (>93%). By using FA as syngas source, the side-reaction of olefin-hydrogenation was greatly depressed. The in situ FT-IR and the high-pressure 1H NMR spectroscopic analyses were applied to reveal how FA behaves dually as CO surrogate and hydrogen source over L1-Rh(acac)(CO)2 catalytic system, based on which the deeply insight into the catalytic mechanism of hydroformylation of olefins with FA as syngas alternative was offered.
High-Quality Gasoline Directly from Syngas by Dual Metal Oxide–Zeolite (OX-ZEO) Catalysis
Li, Na,Jiao, Feng,Pan, Xiulian,Chen, Yuxiang,Feng, Jingyao,Li, Gen,Bao, Xinhe
supporting information, p. 7400 - 7404 (2019/05/10)
Despite significant efforts towards the direct conversion of syngas into liquid fuels, the selectivity remains a challenge, particularly with regard to high-quality gasoline with a high octane number and a low content of aromatic compounds. Herein, we show that zeolites with 1D ten-membered-ring (10-MR) channel structures such as SAPO-11 and ZSM-22 in combination with zinc- and manganese-based metal oxides (ZnaMnbOx) enable the selective synthesis of gasoline-range hydrocarbons C5–C11 directly from syngas. The gasoline selectivity reached 76.7 % among hydrocarbons, with only 2.3 % CH4 at 20.3 % CO conversion. The ratio of isoparaffins to n-paraffins was as high as 15, and the research octane number was estimated to be 92. Furthermore, the content of aromatic compounds in the gasoline was as low as 16 %. The composition and structure of ZnaMnbOx play an important role in determining the overall activity. This process constitutes a potential technology for the one-step synthesis of environmentally friendly gasoline with a high octane number from a variety of carbon resources via syngas.
UPGRADING 5-NONANONE
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Paragraph 0104-0108, (2018/04/20)
Provided are fuel components, a method for producing fuel components, use of the fuel components and fuel containing the fuel components based on 5-nonanone.
Fischer–Tropsch synthesis with cobalt catalyst and zeolite multibed arrangement
Asalieva, E. Yu.,Kul’chakovskaya,Sineva,Mordkovich,Bulychev
, p. 275 - 280 (2016/06/09)
The role of zeolite in transformations of hydrocarbons produced from CO and H2 over a Fischer–Tropsch cobalt catalyst under the conditions of multibed arrangement of the cobalt catalyst and the zeolite has been determined. Hydrocarbon conversion over the HBeta zeolite occurs via the bimolecular mechanism, as evidenced by a low methane yield and a high yield of unsaturated gaseous and liquid hydrocarbons. The conversion over the CaA zeolite obeys the unimolecular mechanism, as evidenced by the formation of increased amounts of methane and saturated gaseous C2–C4 hydrocarbons.
Production of liquid hydrocarbon fuels with acetoin and platform molecules derived from lignocellulose
Zhu, Chenjie,Shen, Tao,Liu, Dong,Wu, Jinglan,Chen, Yong,Wang, Linfeng,Guo, Kai,Ying, Hanjie,Ouyang, Pingkai
supporting information, p. 2165 - 2174 (2016/04/19)
Acetoin, a novel C4 platform molecule derived from new ABE (acetoin-butanol-ethanol) type fermentation via metabolic engineering, was used for the first time as a bio-based building block for the production of liquid hydrocarbon fuels. A series of diesel or jet fuel range C9-C14 straight, branched, or cyclic alkanes were produced in excellent yields by means of C-C coupling followed by hydrodeoxygenation reactions. Hydroxyalkylation/alkylation of acetoin with 2-methylfuran was investigated over a series of solid acid catalysts. Among the investigated candidates, zirconia supported trifluoromethanesulfonic acid showed the highest activity and stability. In the aldol condensation step, a basic ionic liquid [H3N+-CH2-CH2-OH][CH3COO-] was identified as an efficient and recyclable catalyst for the reactions of acetoin with furan based aldehydes. The scope of the process has also been studied by reacting acetoin with other aldehydes, and it was found that abnormal condensation products were formed from the reactions of acetoin with aromatic aldehydes through an aldol condensation-pinacol rearrangement route when amorphous aluminium phosphate was used as a catalyst. And the final hydrodeoxygenation step could be achieved by using a simple and handy Pd/C + H-beta zeolite system, and no or a negligible amount of oxygenates was observed after the reaction. Excellent selectivity was also observed using the present system, and the clean formation of hydrocarbons with a narrow distribution of alkanes occurred in most cases.
Activation and isomerization of hydrocarbons over WO3/ZrO2 catalysts. II. Influence of tungsten loading on catalytic activity: Mechanistic studies and correlation with surface reducibility and tungsten surface species
Di Gregorio, Francois,Keller, Nicolas,Keller, Valerie
, p. 159 - 171 (2008/09/21)
We studied the correlation among the catalytic behavior of WO3/ZrO2 samples toward unsaturated and saturated hydrocarbons transformation, tungsten surface species oxidation states, and the crystallographic structure of the zirconia support. Different tungsten-loaded catalysts were studied, from 9 wt% (near-monolayer coverage) to 30 wt%. The resulting WO3/ZrO2 materials were obtained by impregnation of a tungsten salt on either a commercially available monoclinic zirconia or an amorphous hydroxide, ZrOx(OH)4-2x, followed by a calcination step (according to the Hino and Arata procedure), leading to a tetragonal structure. In contrast to previous works, here we demonstrate that the crystallographic structure of zirconia has no influence on catalytic properties. Correlations with XPS analyses revealed two aspects of catalytic behavior that depend strongly on the catalyst reducibility and thus on the W surface species oxidation states. First, on hardly reducible (tungsten loadings a purely acidic monomolecular mechanism for both isomerization (largely predominant) and cracking reactions, associated with W6+ and W5+ surface species, was demonstrated. Second, on easily reducible (tungsten loadings >15 wt%) or deeply reduced (over 723 K) surfaces, a bifunctional mechanism associating dehydrogenating/hydrogenating properties occurring on metallic tungsten and acidic isomerization and cracking on W5+ and W6+ surface species was observed. However, in this last case, we could not exclude the participation of a purely metallic isomerization mechanism occurring through σ-alkyl adsorbed species on the β-W metallic phase. A more pronounced reduction then led to an increase in the extensive hydrogenolysis mechanism, causing catalyst deactivation.
Alkene oligomerization process
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Page 4-5, (2008/06/13)
A process for oligomerising alkenes having from 3 to 6 carbon atoms which comprises contacting a feedstock comprising a) one or several alkenes having x carbon atoms, and, b) optionally, one or several alkenes having y carbon atoms, x and y being different, with a catalyst containing a zeolite of the MFS structure type, under conditions to obtain selectively oligomeric product containing predominant amounts of certain oligomers. The process is carried out at a temperature comprised between 125 and 175° C. when the feedstock contains only alkenes with 3 carbon atoms and between 140 and 240° C., preferably between 140 and 200° C. when the feedstock contains comprises at least one alkene with 4 or more carbon atoms.
