F+:Highly flammable;
75-31-0Relevant articles and documents
Reductive amination of isopropanol to monoisopropylamine over Ni-Fe/Γ-Al2O3 catalysts: Synergetic effect of Ni-Fe alloy formation
Hong, Eunpyo,Bang, Seonu,Cho, Jun Hee,Jung, Kwang Deog,Shin, Chae-Ho
, p. 146 - 153 (2017)
We herein reported the syntheses of 17?wt% Ni-xFe/γ-Al2O3 catalysts containing different Fe/Ni molar ratios (x?=?0–0.7) via an incipient wetness impregnation method, followed by subsequent investigation of their catalytic properties in the reductive amination of isopropanol (IPA). We attempted to reveal the synergetic effect of bimetallic Ni-Fe on γ-Al2O3 support through characterization of the catalysts by N2-sorption, X-ray diffraction, H2-temperature-programmed reduction, and X-ray photoelectron spectroscopy. We found that conversion and selectivity to monoisopropylamine (MIPA) through the reductive amination of IPA was influenced by the reducibility of the catalysts. In addition, the surface Ni0 content increased upon the addition of Fe species, with a maximum Ni0 content being reached at a Fe/Ni molar ratio of 0.3. This molar ratio also yielded the highest conversion and MIPA selectivity, and no deactivation was observed for 100?h on stream in the presence of hydrogen gas. In addition, reaction parameters, such as the partial pressures of H2 and NH3, the space velocity, and the reaction temperature were also examined to optimize the experimental conditions.
A Lewis Base Nucleofugality Parameter, NFB, and Its Application in an Analysis of MIDA-Boronate Hydrolysis Kinetics
García-Domínguez, Andrés,Gonzalez, Jorge A.,Leach, Andrew G.,Lloyd-Jones, Guy C.,Nichol, Gary S.,Taylor, Nicholas P.
supporting information, (2022/01/04)
The kinetics of quinuclidine displacement of BH3 from a wide range of Lewis base borane adducts have been measured. Parameterization of these rates has enabled the development of a nucleofugality scale (NFB), shown to quantify and predict the leaving group ability of a range of other Lewis bases. Additivity observed across a number of series R′3-nRnX (X = P, N; R′ = aryl, alkyl) has allowed the formulation of related substituent parameters (nfPB, nfAB), providing a means of calculating NFB values for a range of Lewis bases that extends far beyond those experimentally derived. The utility of the nucleofugality parameter is explored by the correlation of the substituent parameter nfPB with the hydrolyses rates of a series of alkyl and aryl MIDA boronates under neutral conditions. This has allowed the identification of MIDA boronates with heteroatoms proximal to the reacting center, showing unusual kinetic lability or stability to hydrolysis.
Development and Application of Efficient Ag-based Hydrogenation Catalysts Prepared from Rice Husk Waste
Unglaube, Felix,Kreyenschulte, Carsten Robert,Mejía, Esteban
, p. 2583 - 2591 (2021/04/09)
The development of strategies for the sustainable management and valorization of agricultural waste is of outmost importance. With this in mind, we report the use of rice husk (RH) as feedstock for the preparation of heterogeneous catalysts for hydrogenation reactions. The catalysts were prepared by impregnating the milled RH with a silver nitrate solution followed by carbothermal reduction. The composition and morphology of the prepared catalysts were fully assessed by IR, AAS, ICP-MS, XPS, XRD and STEM techniques. This novel bio-genic silver-based catalysts showed excellent activity and remarkable selectivity in the hydrogenation of nitro groups in both aromatic and aliphatic substrates, even in the presence of reactive functionalities like halogens, carbonyls, borate esters or nitriles. Recycling experiments showed that the catalysts can be easily recovered and reused multiple times without significant drop in performance and without requiring re-activation.
Rapid and Quantitative Profiling of Substrate Specificity of ω-Transaminases for Ketones
Han, Sang-Woo,Shin, Jong-Shik
, p. 3287 - 3295 (2019/06/21)
ω-Transaminases (ω-TAs) have gained growing attention owing to their capability for asymmetric synthesis of chiral amines from ketones. Reliable high-throughput activity assay of ω-TAs is essential in carrying out extensive substrate profiling and establishing a robust screening platform. Here we report spectrophotometric and colorimetric methods enabling rapid quantitation of ω-TA activities toward ketones in a 96-well microplate format. The assay methods employ benzylamine, a reactive amino donor for ω-TAs, as a cosubstrate and exploit aldehyde dehydrogenase (ALDH) as a reporter enzyme, leading to formation of benzaldehyde detectable by ALDH owing to concomitant NADH generation. Spectrophotometric substrate profiling of two wild-type ω-TAs of opposite stereoselectivity was carried out at 340 nm with 22 ketones, revealing subtle differences in substrate specificities that were consistent with docking simulation results obtained with cognate amines. Colorimetric readout for naked eye detection of the ω-TA activity was also demonstrated by supplementing the assay mixture with color-developing reagents whose color reaction could be quantified at 580 nm. The colorimetric assay was applied to substrate profiling of an engineered ω-TA for 24 ketones, leading to rapid identification of reactive ketones. The ALDH-based assay is expected to be promising for high-throughput screening of enzyme collections and mutant libraries to fish out the best ω-TA candidate as well as to tailor enzyme properties for efficient amination of a target ketone.
Catalytic amino acid production from biomass-derived intermediates
Deng, Weiping,Wang, Yunzhu,Zhang, Sui,Gupta, Krishna M.,Hülsey, Max J.,Asakura, Hiroyuki,Liu, Lingmei,Han, Yu,Karp, Eric M.,Beckham, Gregg T.,Dyson, Paul J.,Jiang, Jianwen,Tanaka, Tsunehiro,Wang, Ye,Yan, Ning
, p. 5093 - 5098 (2018/05/23)
Amino acids are the building blocks for protein biosynthesis and find use in myriad industrial applications including in food for humans, in animal feed, and as precursors for bio-based plastics, among others. However, the development of efficient chemical methods to convert abundant and renewable feedstocks into amino acids has been largely unsuccessful to date. To that end, here we report a heterogeneous catalyst that directly transforms lignocellulosic biomass-derived α-hydroxyl acids into α-amino acids, including alanine, leucine, valine, aspartic acid, and phenylalanine in high yields. The reaction follows a dehydrogenation-reductive amination pathway, with dehydrogenation as the rate-determining step. Ruthenium nanoparticles supported on carbon nanotubes (Ru/CNT) exhibit exceptional efficiency compared with catalysts based on other metals, due to the unique, reversible enhancement effect of NH3 on Ru in dehydrogenation. Based on the catalytic system, a two-step chemical process was designed to convert glucose into alanine in 43% yield, comparable with the well-established microbial cultivation process, and therefore, the present strategy enables a route for the production of amino acids from renewable feedstocks. Moreover, a conceptual process design employing membrane distillation to facilitate product purification is proposed and validated. Overall, this study offers a rapid and potentially more efficient chemical method to produce amino acids from woody biomass components.
METHOD FOR PRODUCING N-ETHYL-DIISOPROPYLAMINE
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Paragraph 0070-0076, (2017/01/26)
A process for preparing N-ethyldiisopropylamine by reacting acetaldehyde with diisopropylamine and hydrogen at elevated temperature and under pressure in the presence of a heterogeneous hydrogenation catalyst, the catalyst being a supported transition metal catalyst comprising Pd and/or Pt as catalytically active metal, wherein the diisopropylamine used has a purity of 58% to 94% by weight and impurities as follows: 3% to 20% by weight of water, 3% to 20% by weight of isopropanol, 0% to 2% by weight of others.
O -Phthalaldehyde catalyzed hydrolysis of organophosphinic amides and other P(O)-NH containing compounds
Li, Bin-Jie,Simard, Ryan D.,Beauchemin, André M.
supporting information, p. 8667 - 8670 (2017/08/10)
Over 50 years ago, Jencks and Gilchrist showed that formaldehyde catalyses the hydrolysis of phosphoramidate through electrophilic activation, induced by covalent attachment to its nitrogen atom. Given our interest in the use of aldehydes as catalysts, this work was revisited to identify a superior catalyst, o-phthalaldehyde, which facilitates hydrolyses of various organophosphorus compounds bearing P(O)-NH subunits under mild conditions. Interestingly, chemoselective hydrolysis of the P(O)-N bonds could be accomplished in the presence of P(O)-OR bonds.
Versatile Dynamic Covalent Assemblies for Probing π-Stacking and Chirality Induction from Homotopic Faces
Ye, Hebo,Hai, Yu,Ren, Yulong,You, Lei
supporting information, p. 3804 - 3809 (2017/03/27)
Herein we report for the first time the use of dynamic covalent reactions (DCRs) for building a π-stacking model system and further quantifying its substituent effects (SEs), which remain a topic of debate despite the rich history of stacking. A general DCR between 10-methylacridinium ion and primary amines was discovered, in which π-stacking played a stabilizing role. Facile quantification of SEs with in situ competing π-stacking systems was next achieved in the form of amine exchange exhibiting structural diversity by simply varying components. The linear correlation with σm in Hammett plots indicates the dominance of purely electrostatic SEs, and the additivity of SEs is in line with the direct interaction model. With α-chiral amines π-stacking within the adduct enabled chirality transfer from homotopic faces. The strategy of dynamic covalent assembly should be appealing to future research of probing weak interactions and manipulating chirality.
A hydrogenation of acetone ammonia synthesis isopropylamine method (by machine translation)
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Paragraph 0030; 0031; 0032; 0033; 0034; 0035; 0036-0040, (2017/03/14)
The invention discloses a method for hydrogenation of acetone ammonia synthesis isopropylamine method, the reaction feeding before replace the nitrogen in the reactor of the air, and then the preheating of the hydrogen is introduced in the reactor, the catalyst in the reactor temperature is raised to 90 - 180 °C, in the reactor pressure to rise to 0.2 - 1.8 mpa; after preheating into acetone, hydrogen, and ammonia are mixed in the material into the reactor, the catalyst in the presence of 0.2 - 1.8 mpa, 90 - 180 °C hydrogenated ammoniation reaction, to get the crude product, prepared by precipitating the crude product after cooling separator for separating gas and liquid, liquid is rough isopropylamine. The invention make coarse isopropylamine in isopropylamine content is high, acetone conversion rate 100%, isopropylamine selectively in 99.7% or more. (by machine translation)
NHC-based coordination polymers as solid molecular catalysts for reductive amination of biomass levulinic acid
Sun, Zheming,Chen, Jiangbo,Tu, Tao
, p. 789 - 794 (2017/08/18)
A class of robust solid molecular NHC-based catalysts were readily fabricated via self-assembly from a p-phenylene-bridged bis-benzimidazolium salt with selected metal precursors. Among them, the NHC-Ru polymer demonstrated high catalytic activity and excellent stability as a solid molecular catalyst for the solvent-free reductive amination of biomass levulinic acid with inexpensive ammonium formate, furnishing a challenging unprotected 5-methyl-2-pyrrolidone quantitatively at a 0.15 mol% catalyst loading. The solid catalyst was readily recovered and reused for 37 runs without obvious loss of activity. Remarkably, a TON value up to 6.7 × 104 was achieved in a molar-scale reaction with a catalyst loading at 0.001 mol%. Inspired by the results of a preliminary mechanistic study, notably, one-pot tandem reductive reactions of LA with aldehydes or ketones were successfully developed, affording a variety of structurally intriguing and functional N-substituted 5-methyl-2-pyrrolidones in high chemo-selectivity with good to excellent yields.
