617-51-6Relevant articles and documents
Bi-Functional Magnesium Silicate Catalyzed Glucose and Furfural Transformations to Renewable Chemicals
Kumar, Abhinav,Srivastava, Rajendra
, p. 4807 - 4816 (2020/08/24)
Bio-refinery is attracting significant interest to produce a wide range of renewable chemicals and fuels from biomass that are alternative to fossil fuel derived petrochemicals. Similar to petrochemical industries, bio-refinery also depends on solid zeolite catalysts. Acid-base catalysis plays pivotal role in producing a wide range of chemicals from biomass. Herein, the Mg framework substituted MTW zeolite is synthesized and explored in the valorisation of glucose and furfural. Bi-functional (acidic and basic) characteristics are confirmed using pyridine adsorbed FT?IR analysis and NH3 and CO2 temperature-programmed desorption techniques. Textural properties and morphological information are retrieved from N2-sorption, X-ray photoelectron spectroscopy, and electron microscopy. The activity of the catalyst is demonstrated in the selective isomerisation of glucose to fructose in ethanol. Glucose is converted to methyl lactate in high yield using the same catalyst. Further, the bi-functional activity of this catalyst is demonstrated in the production of fuel precursor by the reaction of furfural and isopropanol. Mg?MTW zeolite exhibits excellent activity in the production of all these chemicals and fuel derivative. The catalyst exhibits no significant loss in the activity even after five recycles. One simple catalyst affording three renewable synthetic intermediates from glucose and furfural will attract significant attention to catalysis researchers and industrialists.
ANTIVIRAL PRODRUGS OF TENOFOVIR
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Page/Page column 30; 34; 35, (2018/09/26)
Compounds of Formula I: and pharmaceutically acceptable salts and co-crystals thereof are useful for the inhibition of HIV reverse transcriptase. The compounds may also be useful for the prophylaxis or treatment of infection by HIV and in the prophylaxis, delay in the onset or progression, and treatment of AIDS. The compounds and their salts can be employed as ingredients in pharmaceutical compositions, optionally in combination with other antiviral agents, immunomodulators, antibiotics or vaccines.
Method of synthesizing acid ester
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Paragraph 0052-0054, (2017/02/23)
PROBLEM TO BE SOLVED: To provide a method for manufacturing lactate without the corrosion of a reactor nor trouble of waste liquid processing, using glycerol separated and generated from various oil-and-fats, including glycerol by-produced in the manufacture of a biodiesel fuel.SOLUTION: In the method, the lactate is synthesized from the glycerol in the presence of a solid basic catalyst, using alcohol in a high-temperature and high-pressure state as a reaction medium.
Dynamic kinetic resolution of α-substituted β-ketoesters catalyzed by Baeyer-Villiger monooxygenases: Access to enantiopure α-hydroxy esters
Rioz-Martínez, Ana,Cuetos, Aníbal,Rodríguez, Cristina,De Gonzalo, Gonzalo,Lavandera, Iván,Fraaije, Marco W.,Gotor, Vicente
supporting information; experimental part, p. 8387 - 8390 (2011/10/09)
BVMOs make a play: The dynamic kinetic resolution of racemic α-alkyl-β-ketoesters was performed through a selective Baeyer-Villiger oxidation employing different Baeyer-Villiger monooxygenases (BVMOs) in mild basic media. The product diesters were obtained with excellent yields and enantioselectivities, and used as precursors for optically active α-hydroxy esters.
Organosoluble zirconium phosphonate nanocomposites and their supported chiral ruthenium catalysts: The first example of homogenization of inorganic-supported catalyst in asymmetric hydrogenation
Chen, Taotao,Ma, Xuebing,Wang, Xiaojia,Wang, Qiang,Zhou, Jinqin,Tang, Qian
experimental part, p. 3325 - 3335 (2011/05/13)
In this article, we report the synthesis, structure, morphologies, and asymmetric catalytic properties of a series of novel organosoluble zirconium phosphonate nanocomposites and their supported chiral ruthenium catalysts, which have a good organosolubility (0.1-0.5 g mL-1) in various solvents and mesoporous, filiform, and layered structures. Due to the organosoluble properties in various organic solvents, the first homogenization of zirconium phosphonate-supported catalyst was realized in the field of catalysis. In the asymmetric hydrogenation of substituted α-ketoesters, enantioselectivities (74.3-84.7% ee) and isolated yields (86.7-93.6%) were higher than the corresponding homogeneous Ru(p-cymene)(S-BINAP)Cl2 due to the confinement effect caused by the remaining mesopores in the backbone of the zirconium phosphonate. After completing the reaction, the supported catalyst can be readily recovered in quantitative yield by adding cyclohexane and centrifugation, and reused for five consecutive runs without significant loss in catalytic activity.
Hydroxyapatite supported lewis acid catalysts for the transformation of trioses in alcohols
Zhang, Zehui,Zhao, Zongbao
experimental part, p. 70 - 73 (2011/10/05)
We prepared hydroxyapatite-supported tin(II) chloride and tin(IV) chloride Lewis acid catalysts. These catalysts showed catalytic activity for the transformation of trioses in alcohols to yield alkyl lactates. Under optimal conditions, n-butyl lactate was obtained in 73.5 yield when dihydroxyacetone and n-butanol were treated with hydroxyapatite-supported tin(II) chloride.
Zeolite-catalysed conversion of C3 sugars to alkyl lactates
Pescarmona, Paolo P.,Janssen, Kris P. F.,Delaet, Chloe,Stroobants, Christophe,Houthoofd, Kristof,Philippaerts, An,De Jonghe, Chantal,Paul, Johan S.,Jacobs, Pierre A.,Sels, Bert F.
experimental part, p. 1083 - 1089 (2010/08/20)
The direct conversion of C3 sugars (or trioses) to alkyl lactates was achieved using zeolite catalysts. This reaction represents a key step towards the efficient conversion of bio-glycerol or formaldehyde to added-value chemicals such as lactate derivatives. The highest yields and selectivities towards the desired lactate product were obtained with Ultrastable zeolite Y materials having a low Si/Al ratio and a high content of extra-framework aluminium. Correlating the types and amounts of acid sites present in the different zeolites reveals that two acid functions are required to achieve excellent catalysis. Bronsted acid sites catalyse the conversion of trioses to the reaction intermediate pyruvic aldehyde, while Lewis acid sites further assist in the intramolecular rearrangement of the aldehyde into the desired lactate ester product. The presence of strong zeolitic Bronsted acid sites should be avoided as much as possible, since they convert the intermediate pyruvic aldehyde into alkyl acetals instead of lactate esters. A tentative mechanism for the acid catalysis is proposed based on reference reactions and isotopically labelled experiments. Reusability of the USY catalyst is demonstrated for the title reaction.
ZEOLITE-CATALYZED PREPARATION OF ALPHA-HYDROXY CARBOXYLIC ACIDS AND ESTERS THEREOF
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Page/Page column 3, (2010/06/11)
A process for the production of lactic acid and 2-hydroxy-3-butenoic acid or esters thereof by conversion of glucose, fructose, sucrose, xylose and glycolaldehyde dissolved in a solvent in presence of a solid Lewis acidic catalyst.
Zeolite-catalyzed preparation of alpha-hydroxy carboxylic acid compounds and esters thereof
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Page/Page column 6, (2010/06/11)
A process for the production of lactic acid and 2-hydroxy-3-butenoic acid or esters thereof by conversion of glucose, fructose, sucrose, xylose and glycolaldehyde dissolved in a solvent in presence of a solid Lewis acidic catalyst.
Synthesis of alkyl (R)-lactates and alkyl (S,S)-O-lactyllactates by alcoholysis of rac-lactide using Novozym 435
Jeon, Nan Young,Ko, Sung-Jin,Won, Keehoon,Kang, Han-Young,Kim, Bum Tae,Lee, Yeon Soo,Lee, Hyuk
, p. 6517 - 6520 (2007/10/03)
Enzymatic alcoholysis of rac-lactide for kinetic resolution was carried out in organic solvents. Effects of organic solvent, reaction temperature, and alcohol as a nucleophile were also investigated in Novozym 435-catalyzed alcoholysis of rac-lactide. Both alkyl (R)-lactate and alkyl (S,S)-O-lactyllactate were simultaneously obtained in high yields (>45%) and high enantiopurities (>97% ee) through Novozym 435-catalyzed ring-opening of rac-lactide and subsequent enantioselective alcoholysis of the resultant alkyl O-lactyllactate.
