626-95-9Relevant academic research and scientific papers
Partially biobased polymers: The synthesis of polysilylethers via dehydrocoupling catalyzed by an anionic iridium complex
Zhai, Xiao-Yong,Wang, Xiao-Qing,Ding, Yi-Xuan,Zhou, Yong-Gui
, p. 1197 - 1200 (2020)
Partially biobased polysilylethers (PSEs) are synthesized via dehydrocoupling polymerization catalyzed by an anionic iridium complex. Different types (AB type or AA and BB type) of monomers are suitable. Levulinic acid (LA) and succinic acid (SA) have been ranked within the top 10 chemicals derived from biomass. BB type monomers (diols) derived from LA and SA have been applied to the synthesis of PSEs. The polymerization reactions employ an air-stable anionic iridium complex bearing a functional bipyridonate ligand as catalyst. Moderate to high yields of polymers with number-average molecular weights (Mn) up to 4.38 × 104 were obtained. A possible catalytic cycle via an Ir-H species is presented. Based on the results of kinetic experiments, apparent activation energy of polymerization in the temperature range of 0–10 °C is about 38.6 kJ/mol. The PSEs synthesized from AA and BB type monomers possess good thermal stability (T5 = 418 °C to 437 °C) and low glass-transition temperature (Tg = ?49.6 °C).
Tunable copper-catalyzed chemoselective hydrogenolysis of biomass-derived γ-valerolactone into 1,4-pentanediol or 2-methyltetrahydrofuran
Du, Xian-Long,Bi, Qing-Yuan,Liu, Yong-Mei,Cao, Yong,He, He-Yong,Fan, Kang-Nian
, p. 935 - 939 (2012)
Direct conversion of γ-valerolactone, which is one of the most significant cellulose-derived compounds, into 1,4-pentanediol was carried out by chemoselective hydrogenolysis catalyzed by a simple yet versatile copper-zirconia catalyst. Depending on the reaction conditions, 2-methyltetrahydrofuran could also be obtained in excellent yields.
Transformation of γ-valerolactone into 1,4-pentanediol and 2-methyltetrahydrofuran over Zn-promoted Cu/Al2O3catalysts
Arai, Masahiko,Cheng, Haiyang,Lin, Weiwei,Liu, Ke,Liu, Qiang,Shi, Ruhui,Wang, Zhuangqing,Wu, Peixuan,Zhang, Chao,Zhao, Fengyu,Zhao, Zhenbo
, p. 4412 - 4423 (2020)
The transformation of γ-valerolactone (GVL) into 1,4-pentanediol (1,4-PDO) and 2-methyltetra-hydrofuran (2-MTHF) in the presence of H2, one of the useful biomass conversion and utilization processes, was investigated with monometallic Cu/Al2O3 and bimetallic ZnCu/Al2O3 catalysts. A 10 wt% Cu-loaded monometallic catalyst produced 1,4-PDO and 2-MTHF in comparable quantities at a medium conversion (～50%). When Zn was added in a range of Zn/Cu molar ratios of up to 2, in contrast, the catalysts yielded 1,4-PDO in a high selectivity of about 97% at low and high conversion levels. In addition, the 1,4-PDO selectivity over the ZnCu/Al2O3 catalysts remained almost unchanged during recycled runs. That is, the addition of Zn to Cu/Al2O3 switched the product selectivity and improved the catalyst stability and reusability. Furthermore, the physicochemical properties of the catalysts were characterized by several methods including XRD, TEM, TPR, XPS, FTIR of adsorbed pyridine, and so on. On the basis of those results, the relationships between the catalytic performance (activity, selectivity, and reusability) and the catalyst structural features were discussed.
Properties of Novel Polyesters Made from Renewable 1,4-Pentanediol
Stadler, Bernhard M.,Brandt, Adrian,Kux, Alexander,Beck, Horst,de Vries, Johannes G.
, p. 556 - 563 (2020)
Novel polyester polyols were prepared in high yields from biobased 1,4-pentanediol catalyzed by non-toxic phosphoric acid without using a solvent. These oligomers are terminated with hydroxyl groups and have low residual acid content, making them suitable for use in adhesives by polyurethane formation. The thermal behavior of the polyols was studied by differential scanning calorimetry, and tensile testing was performed on the derived polyurethanes. The results were compared with those of polyurethanes obtained with fossil-based 1,4-butanediol polyester polyols. Surprisingly, it was found that a crystalline polyester was obtained when aliphatic long-chain diacids (>C12) were used as the diacid building block. The low melting point of the C12 diacid-based material allows the development of biobased shape-memory polymers with very low switching temperatures (0 °C), an effect that has not yet been reported for a material based on a simple binary polyester. This might find application as thermosensitive adhesives in the packaging of temperature-sensitive goods such as pharmaceuticals. Furthermore, these results indicate that, although 1,4-pentanediol cannot be regarded as a direct substitute for 1,4-butanediol, its novel structure expands the toolbox of the adhesives, coatings, or sealants formulators.
Manganese-Catalyzed Hydrogenation of Sclareolide to Ambradiol
Zubar, Viktoriia,Lichtenberger, Niels,Schelwies, Mathias,Oeser, Thomas,Hashmi, A. Stephen K.,Schaub, Thomas
, (2021/11/16)
The hydrogenation of (+)-Sclareolide to (?)-ambradiol catalyzed by a manganese pincer complex is reported. The hydrogenation reaction is performed with an air- and moisture-stable manganese catalyst and proceeds under relatively mild reaction conditions at low manganese and base loadings. A range of other esters could be successfully hydrogenated leading to the corresponding alcohols in good to quantitative yields using this easy-to-make catalyst. A scale-up experiment was performed leading to 99.3 % of the isolated yield of (?)-Ambradiol.
METHOD FOR PRODUCING ALCOHOL
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Paragraph 0103-0111; 0124-0127; 0133-0137, (2022/02/05)
The present invention provides a method for selectively producing an alcohol by efficiently hydrogenating a lactone. The present invention is a method for producing an alcohol, the method including hydrogenating a substrate lactone represented by Formula (1), in the presence of a catalyst described below, to produce an alcohol that is represented by Formula (2). In the formulae, R represents a divalent hydrocarbon group which may have a hydroxyl group. The catalyst comprises: metal species including M1 and M2; and a support supporting the metal species, and wherein M1 is rhodium, platinum, ruthenium, iridium, or palladium; M2 is tin, vanadium, molybdenum, tungsten, or rhenium; and the support is hydroxyapatite, fluorapatite, hydrotalcite, or ZrO2.
Synthesis and characterisation of a range of Fe, Co, Ru and Rh triphos complexes and investigations into the catalytic hydrogenation of levulinic acid
Omoruyi, Uwaila,Page, Samuel J.,Apps, Samantha L.,White, Andrew J.P.,Long, Nicholas J.,Miller, Philip W.
, (2021/01/19)
The coordination chemistry of the N-triphos ligand (NP3Ph, 1b) has been investigated with a range of Fe, Co and Rh precursors and found to form either tridentate or bidentate complexes. Reaction of NP3Ph with [Rh(COD)(CH3CN)2]BF4 resulted in the formation of the tridentate complex [Rh(COD)(κ3-NP3Ph)]BF4 (3) in the solid state, however, in solution a bidentate complex predominates in more polar solvents. Reaction of NP3Ph with Fe carbonyl precursors revealed the formation of the bidentate complexes [Fe(CO)3(κ1,κ2-NP3Ph)Fe(CO)4] (4) and [Fe(CO)3(κ2-NP3Ph)] (5), while reaction with FeBr2 resulted in the paramagnetic bidentate complex [Fe(Br)2(κ2-NP3Ph)] (6). Reaction of NP3Ph with CoCl2 gave a dimeric Co species [(κ2-NP3Ph)CoCl(κ1,κ2-NP3Ph)CoCl3] (7), while Zn powder reduction of NP3Ph Co halides resulted in the formation of the tridentate complexes of the type: [Co(X)(κ3-NP3Ph)]. The related triphos Ru complex, [Ru(CO3)(CO)(κ3-CP3Ph)] (2), has also been isolated and characterised. Preliminary catalytic hydrogenation of levulinic acid (LA) was conducted with 2 and 3. The Ru complex was found to be catalytically active, giving high conversions of LA to form gamma-vvvalerolactone (GVL) and 1,4-pentanediol (1,4-PDO), while 3 was found to be catalytically inactive. In situ catalytic testing with 1b and Fe(BF4)2.6H2O resulted in low conversions of LA while a combination of 1b and Co(BF4)2.6H2O gave high conversions to GVL.
Chemoselective and Site-Selective Reductions Catalyzed by a Supramolecular Host and a Pyridine-Borane Cofactor
Morimoto, Mariko,Cao, Wendy,Bergman, Robert G.,Raymond, Kenneth N.,Toste, F. Dean
supporting information, p. 2108 - 2114 (2021/02/06)
Supramolecular catalysts emulate the mechanism of enzymes to achieve large rate accelerations and precise selectivity under mild and aqueous conditions. While significant strides have been made in the supramolecular host-promoted synthesis of small molecules, applications of this reactivity to chemoselective and site-selective modification of complex biomolecules remain virtually unexplored. We report here a supramolecular system where coencapsulation of pyridine-borane with a variety of molecules including enones, ketones, aldehydes, oximes, hydrazones, and imines effects efficient reductions under basic aqueous conditions. Upon subjecting unprotected lysine to the host-mediated reductive amination conditions, we observed excellent ?-selectivity, indicating that differential guest binding within the same molecule is possible without sacrificing reactivity. Inspired by the post-translational modification of complex biomolecules by enzymatic systems, we then applied this supramolecular reaction to the site-selective labeling of a single lysine residue in an 11-amino acid peptide chain and human insulin.
A green solvent diverts the hydrogenation of γ–valerolactone to 1,4 - pentandiol over Cu/SiO2
Campisi, Sebastiano,Cappelletti, Giuseppe,Cavuoto, Denise,Gervasini, Antonella,Marelli, Marcello,Ravasio, Nicoletta,Scotti, Nicola,Zaccheria, Federica
, (2021/10/25)
A new process for the selective hydrogenation of γ-valerolactone (GVL) to 1,4-pentanediol (1,4-PDO), interesting biobased monomer, has been set up. It relies on the use of a non-noble, nontoxic metal such as Cu on a very simple oxide support, namely silica in a green solvent such as Cyclopentyl Methyl Ether (CPME). The role of the solvent was not only to ensure more sustainable experimental conditions but also to influence the activity and selectivity of the catalyst by tuning the surface acidity. Thus, the activity of Cu catalysts supported on different types of silica was found to depend on some parameters, such as: the support wettability, determined through contact angle and TGA measurements, Cu-dispersion, determined by X-ray photoelectron spectroscopy (XPS) and, in particular, on the nature and effective number of the acid sites on the surface. The last ones were measured through volumetric liquid-solid acid-base titrations with 2-phenylethylamine probe carried out in different reaction solvents and pyridine titrations by Fourier-transform infrared spectroscopy (FT-IR), respectively. Once the best silica support in terms of wettability, in turn affecting Cu dispersion, was identified, CPME was found to be able to boost the catalyst activity and selectivity by modifying the number and strenght of surface acidic sites. The use of this solvent and the fine tuning of the hydrophilic/hydrophobic properties of the silica allowed to reach 78% yield in 1,4-PDO at 160 °C and P(H2) of 50 bar.
Synthesis method of pentanediol, and synthesis method for preparing biomass-based pentadiene through conversion of levulinic acid and derivatives of levulinic acid
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Paragraph 0178-0181; 0186-0189; 0202-0205, (2021/04/07)
The invention provides a synthesis method of pentanediol, and the method comprises the following steps: carrying out conversion reaction on a mixed solution obtained by mixing levulinic acid and/or levulinic acid derivatives, a catalyst and an organic solvent in a hydrogen-containing atmosphere to obtain the pentanediol. According to the method, a large amount of cheap and easily available bio-based chemical levulinic acid or derivatives thereof can be utilized, pentanediol is obtained through catalytic conversion, and m-pentadiene is further obtained. The raw materials are derived from renewable resources, the m-pentadiene is prepared through hydrogenation and dehydration, and particularly, a green and sustainable process route for synthesizing the m-pentadiene is finally obtained through a dehydration reaction route and construction of a dehydration catalyst. The invention provides a method for green and sustainable synthesis of linear pentadiene based on bio-based chemical conversion, and the method has the advantages of simple operation, short flow, no need of harsh experimental conditions, easy preparation of raw materials and catalysts, and large-scale synthesis prospect.
