Single step conversion of cellulose to levulinic acid using temperature-responsive dodeca-aluminotungstic acid catalysts

2016 ◽  
Vol 18 (3) ◽  
pp. 742-752 ◽  
Author(s):  
Zhong Sun ◽  
Lifang Xue ◽  
Shengtian Wang ◽  
Xiaohong Wang ◽  
Junyou Shi

A new series of heteropolyacids [(CH3)3NCH2CH2OH]nH5−nAlW12O40 are used to catalyse the single step conversion of cellulose into levulinic acid (LA). The highest reported yield of LA directly from cellulose was achieved with 74.8% yield and 98.9% conversion in one pot.

2020 ◽  
Vol 7 (1) ◽  
pp. 23-39 ◽  
Author(s):  
Kantharaju Kamanna ◽  
Santosh Y. Khatavi

Multi-Component Reactions (MCRs) have emerged as an excellent tool in organic chemistry for the synthesis of various bioactive molecules. Among these, one-pot MCRs are included, in which organic reactants react with domino in a single-step process. This has become an alternative platform for the organic chemists, because of their simple operation, less purification methods, no side product and faster reaction time. One of the important applications of the MCRs can be drawn in carbon- carbon (C-C) and carbon-heteroatom (C-X; X = N, O, S) bond formation, which is extensively used by the organic chemists to generate bioactive or useful material synthesis. Some of the key carbon- carbon bond forming reactions are Grignard, Wittig, Enolate alkylation, Aldol, Claisen condensation, Michael and more organic reactions. Alternatively, carbon-heteroatoms containing C-N, C-O, and C-S bond are also found more important and present in various heterocyclic compounds, which are of biological, pharmaceutical, and material interest. Thus, there is a clear scope for the discovery and development of cleaner reaction, faster reaction rate, atom economy and efficient one-pot synthesis for sustainable production of diverse and structurally complex organic molecules. Reactions that required hours to run completely in a conventional method can now be carried out within minutes. Thus, the application of microwave (MW) radiation in organic synthesis has become more promising considerable amount in resource-friendly and eco-friendly processes. The technique of microwaveassisted organic synthesis (MAOS) has successfully been employed in various material syntheses, such as transition metal-catalyzed cross-coupling, dipolar cycloaddition reaction, biomolecule synthesis, polymer formation, and the nanoparticle synthesis. The application of the microwave-technique in carbon-carbon and carbon-heteroatom bond formations via MCRs with major reported literature examples are discussed in this review.


2004 ◽  
Vol 69 (5) ◽  
pp. 996-1008 ◽  
Author(s):  
Steven J. Langford ◽  
Clint P. Woodward

A strategy in preparing a family of hexameric porphyrin cubes based on the interplay of Sn(IV)-O and Ru(II)-N interactions is described. In this first iteration, we have prepared the heptamer [SnIV(TPyP)·(4)2][Ru(CO)(TPP)]6 (4 = (E)-(3-(4-pyridyl)acrylate)) constituting a 5,10,15,20-tetra(4-pyridyl)porphyrin (TPyP) core and 5,10,15,20-tetraphenylporphyrin (TPP) faces and compared its formation by stepwise and "one-pot" strategies where up to nine components are assembled in a single step in a regiospecific manner. In one example, the heptamer is formed around the template [SnIV(TPyP)·(4)2] bearing pyridine groups in which the nitrogens radiate octahedrally along each vertex. The ability to modulate the axial vertex through choice of pyridine is also demonstrated. 1H NMR measurements on [SnIV(TPyP)·(4)2][Ru(CO)(TPP)]6 indicate that the protons on the core template are extremely shielded as a result of the anisotropy of the peripheral porphyrin units. Various NMR techniques, including NOESY experiments, have been used to characterise the heptamer in solution.


Nanomaterials ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 521
Author(s):  
Juan Carlos Rendón-Angeles ◽  
Zully Matamoros-Veloza ◽  
Jose Luis Rodríguez-Galicia ◽  
Gimyeong Seong ◽  
Kazumichi Yanagisawa ◽  
...  

One-pot hydrothermal preparation of Ca3Cr2Si3O12 uvarovite nanoparticles under alkaline conditions was investigated for the first time. The experimental parameters selected for the study considered the concentration of the KOH solvent solution (0.01 to 5.0 M), the agitation of the autoclave (50 rpm), and the nominal content of Si4+ (2.2–3.0 mole). Fine uvarovite particles were synthesised at 200 °C after a 3 h interval in a highly concentrated 5.0 M KOH solution. The crystallisation of single-phase Ca3Cr2Si3O12 particles proceeded free of by-products via a one-pot process involving a single-step reaction. KOH solutions below 2.5 M and water hindered the crystallisation of the Ca3Cr2Si3O12 particles. The hydrothermal treatments carried out with stirring (50 rpm) and non-stirring triggered the crystallisation of irregular anhedral particles with average sizes of 8.05 and 12.25 nm, respectively. These particles spontaneously assembled into popcorn-shaped agglomerates with sizes varying from 66 to 156 nm. All the powders prepared by the present method exhibited CIE-L*a*b* values that correspond to the Victoria green colour spectral space and have a high near infrared reflectance property. The particle size and structural crystallinity are factors affecting the Victoria pigment optical properties, such as CIE-L*a*b* values, green tonality, and near-infrared reflectance.


Catalysts ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 663
Author(s):  
Luigi di Bitonto ◽  
Valeria D’Ambrosio ◽  
Carlo Pastore

In this work, the transesterification of methyl estolides (ME) extracted from the lipid component present in the sewage scum was investigated. Methyl 10-(R)-hydroxystearate (Me-10-HSA) and Fatty Acid Methyl Esters (FAMEs) were obtained in a single step. A three-level and four factorial Box–Behnken experimental design were used to study the effects of methanol amounts, catalyst, temperature, and reaction time on the transesterification reaction using aluminum chloride hexahydrate (AlCl3·6H2O) or hydrochloric acid (HCl) as catalysts. AlCl3·6H2O was found quite active as well as conventional homogeneous acid catalysts as HCl. In both cases, a complete conversion of ME into Me-10-HSA and FAMEs was observed. The products were isolated, quantified, and fully characterized. At the end of the process, Me-10-HSA (32.3%wt) was purified through a chromatographic separation and analyzed by NMR. The high enantiomeric excess (ee > 92%) of the R-enantiomer isomer opens a new scenario for the valorization of sewage scum.


2018 ◽  
Vol 42 (2) ◽  
pp. 1423-1430 ◽  
Author(s):  
Firdaus Parveen ◽  
Tanmoy Patra ◽  
Sreedevi Upadhyayula

The catalytic conversion of biomass-derived carbohydrates to value-added chemicals, such as 5-hydroxymethylfurfural, levulinic acid, and formic acid, is a commercially important reaction and requires the use of both Lewis and Bronsted acids.


RSC Advances ◽  
2016 ◽  
Vol 6 (55) ◽  
pp. 49760-49763 ◽  
Author(s):  
Qishun Liu ◽  
Fengli Yang ◽  
Heng Yin ◽  
Yuguang Du

Bimetallic oxide catalysts WO3–Ta2O5 are active in converting saccharides into 5-hydroxymethylfurfural (HMF) and levulinic acid (LA) in one-pot reactions.


2012 ◽  
Vol 560-561 ◽  
pp. 294-299
Author(s):  
Xiao Qing Lu ◽  
Min Xing ◽  
Ai Xia Pan ◽  
Yin Yin Wu ◽  
Ji Min Xie ◽  
...  

A novel one-pot catalytic synthesis of 1-benzoylpyrene through acylation of pyrene with benzoyl chloride catalyzed by various Keggin type heteropoly acids (salts) was investigated. Pure 1-benzoylpyrene was obtained and the structure of 1-benzoylpyrene was identified by GC/MS, FT-IR and 1H NMR spectra. H3PW12O40 (PW) was found to be the most active catalyst in the acylation. The yield and the selectivity of 1-benzoylpyrene were up to 97.6 % and 100 %, respectively. The effects of experimental parameters on the catalytic acylation reaction and the recycling performance of PW catalyst were studied. PW catalyst shows well catalytic activity after running for 5 times. The facile product separation and the recycling performance of PW catalyst is expected to contribute to the development of clean and environmentally friendly strategy for the synthesis of 1-benzoylpyrene.


RSC Advances ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 241-250
Author(s):  
Rodiansono ◽  
Maria Dewi Astuti ◽  
Kamilia Mustikasari ◽  
Sadang Husain ◽  
Fathur Razi Ansyah ◽  
...  

The RANEY® Ni–Sn(x) alloy catalysed the one-pot conversion of biomass-derived furfural and levulinic acid to allow remarkable yield of 1,4-pentanediol (up to 90%) under the mild reaction conditions.


2016 ◽  
Vol 12 ◽  
pp. 1772-1777 ◽  
Author(s):  
Lena Huck ◽  
Juan F González ◽  
Elena de la Cuesta ◽  
J Carlos Menéndez

A sequential three-component process is described, starting from 3-arylmethylene-2,5-piperazinediones and involving a one-pot sequence of reactions achieving regioselective opening of the 2,5-diketopiperazine ring and diastereoselective generation of an aziridine ring. This method allows the preparation of N-unprotected, trisubstituted aziridines bearing a peptide side chain under mild conditions. Their transformation into β-trifluoroacetamido-α-ketoamide and α,β-diketoamide frameworks was also achieved in a single step.


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