497-23-4Relevant articles and documents
Oxidation of Diols to Lactones by Nocardia corallina B-276
Luna, Hector,Prasad, Kapa,Repic, Oljan
, p. 303 - 306 (1994)
Several synthetically useful achiral and chiral lactones with high optical purity were prepared by whole-cell oxidation of diols with Nocardia corallina.The absolute stereochemistry of the newly created stereogenic centers was established by comparison with known compounds.In all cases the products were derived fron the oxidation of the pro-S hydroxymethylene group.
Synthesis of surfactants from furfural derived 2[5H]-furanone and fatty amines
Gassama, Abdoulaye,Ernenwein, Cedric,Hoffmann, Norbert
, p. 859 - 865 (2010)
Furfural was oxidized to 2[5H]-furanone 2 using hydrogen peroxide. Furanone 2 was transformed with two equivalents of fatty amines. A condensation and a Michael reaction occurred. Ethyl bromoacetate 5 or methyl acrylate 6 were then added to the secondary amine function. Saponification of the ester function leads to amphoteric surfactants 8a,b,c and 10a,b,c possessing two n-alkyl chains as hydrophobic part. The resulting products can also be considered as Gemini surfactants or twin-tail amphoteric surfactants. Biodegradation studies have been performed on these compounds and the surfactant properties of 8a have been determined in detail.
Reactions of complex ligands Part 91. Application of ring closing metathesis to Fischer-type carbene complexes: Synthesis and structure of medium-sized chromium oxacycloalkenylidenes
Sültemeyer, Jan,D?tz, Karl Heinz,Hupfer, Heike,Nieger, Martin
, p. 26 - 36 (2000)
Six- and seven-membered pentacarbonyl(2-oxacycloalkenylidene) chromium complexes 17 and 6 have been synthesized in moderate to good yields from alkenyloxy(methyl)carbene complex precursors applying an α-alkylation/ruthenium based ring closing metathesis sequence. The ring-closure is hampered for β-alkylated vinylcarbene complexes which may undergo competing intermolecular cross metathesis at the alkenyloxy terminus in low yield.
No-D NMR (No-Deuterium Proton NMR) spectroscopy: A simple yet powerful method for analyzing reaction and reagent solutions
Hoye, Thomas R.,Eklov, Brian M.,Ryba, Troy D.,Voloshin, Mikhail,Yao, Letitia J.
, p. 953 - 956 (2004)
(Equation presented) The title technique is a convenient and powerful method for directly monitoring or assaying any reaction mixture or reagent solution. Examples of some common processes (Fischer esterification, lithiation, butyllithium/THF compatibility, olefin metathesis, and a quantification assay), each interrogated in its native solvent, are presented. The spectral data are easy to acquire, and the information content makes a compelling case for routine use of No-D NMR spectroscopy.
Characteristic flavor formation of thermally processed N-(1-deoxy-α-D-ribulos-1-yl)-glycine: Decisive role of additional amino acids and promotional effect of glyoxal
Zhan, Huan,Cui, Heping,Yu, Junhe,Hayat, Khizar,Wu, Xian,Zhang, Xiaoming,Ho, Chi-Tang
, (2021/09/28)
The role of amino acids and α-dicarbonyls in the flavor formation of Amadori rearrangement product (ARP) during thermal processing was investigated. Comparisons of the volatile compounds and their concentrations when N-(1-deoxy-α-D-ribulos-1-yl)-glycine r
Photocatalytic valorization of furfural to value-added chemicals via mesoporous carbon nitride: a possibility through a metal-free pathway
Battula, Venugopala R.,Chauhan, Deepak K.,Giri, Arkaprabha,Kailasam, Kamalakannan,Patra, Abhijit
, p. 144 - 153 (2022/01/19)
Strategizing the exploitation of renewable solar light could undoubtedly provide new insight into the field of biomass valorization. Therefore, for the first time, we reported a heterogeneous photocatalytic oxidation route of renewable furfural (FUR) to produce industrial feedstocks maleic anhydride (MAN) and 5-hydroxy-2(5H)-furanone (HFO) under simulated solar light (AM 1.5G) using molecular oxygen (O2) as a terminal oxidant and mesoporous graphitic carbon nitride (SGCN) as a photocatalyst. SGCN showed an excellent photoconversion (>95%) of FUR with 42% and 33% selectivity to MAN and HFO, respectively. Moreover, an excellent selectivity towards MAN (66%) under natural sunlight indicates a pioneering route for the sustainable production of MAN. In addition, the underlying mechanistic route of the FUR photo-oxidation was investigated via various experiments including scavenger studies, substrate studies, and electron spin resonance (ESR) studies which constructively proved the pivotal role of singlet oxygen (1O2) and holes (h+) in FUR photo-oxidation.
Chiral Bicyclic Imidazole-Catalyzed Acylative Dynamic Kinetic Resolution for the Synthesis of Chiral Phthalidyl Esters
Zhou, Muxing,Gridneva, Tatiana,Zhang, Zhenfeng,He, Ende,Liu, Yangang,Zhang, Wanbin
supporting information, p. 1641 - 1645 (2020/11/30)
Utilizing a chiral bicyclic imidazole organocatalyst and adopting a continuous injection process, an alternative route has been developed for the efficient synthesis of chiral phthalidyl ester prodrugs via dynamic kinetic resolution of 3-hydroxyphthalides through enantioselective acylation (up to 99 % ee). The computational studies suggest a general base catalytic mechanism differing from the widely accepted nucleophilic catalytic mechanism. The structure analysis of the key transition states shows that the CH-π interactions and not the previously considered cation/π-π interactions between the catalyst and substrate is the dominant factor giving rise to the observed stereocontrol.
A Divergent Paired Electrochemical Process for the Conversion of Furfural Using a Divided-Cell Flow Microreactor
Cao, Yiran,Knijff, Jasper,Delparish, Amin,d'Angelo, Maria Fernanda Neira,Noёl, Timothy
, p. 590 - 594 (2020/12/25)
Furfural is a prominent, non-petroleum-based chemical feedstock material, derived from abundantly available hemicellulose. Hence, its derivatization into other useful biobased chemicals is a subject of high interest in contemporary academic and industrial research activities. While most strategies to convert furfural require energy-intensive reaction routes, the use of electrochemical activation allows to provide a sustainable and green alternative. Herein, a disparate approach for the conversion of furfural is reported based on a divergent paired electrochemical conversion, enabling the simultaneous production of 2(5H)-furanone via an anodic oxidation, and the generation of furfuryl alcohol and/or hydrofuroin via a cathodic reduction. Using water as solvent and NaBr as supporting electrolyte and electron-mediator, a green and sustainable process was developed, which maximizes productive use of electricity and minimizes byproduct formation.
The effect of Br- and alkali in enhancing the oxidation of furfural to maleic acid with hydrogen peroxide
Yang, Tao,Li, Wenzhi,Ogunbiyi, Ajibola T.
, (2021/03/06)
This study was focused on investigating a novel catalytic system for the selective conversion of furfural to maleic acid (MA) in an aqueous system with hydrogen peroxide as an oxidant. A series of experiments that study the impacts of catalyst species, furfural concentration, catalyst dosage, reaction temperature, residue time, hydrogen peroxide concentration, excess water content, and solvent types on the oxidation of furfural to MA was carried out. The results showed that the co-existence of Br- and alkali sites might play a vital role in furfural oxidation, which could improve the MA yield remarkably. Under 90 °C for 3 h, 72.4 % MA yield was obtained with KOH and KBr as co-catalyst in an aqueous phase. Moreover, a possible reaction pathway of furfural oxidation was proposed on the basis of our reaction system.
Metal Sub-nanoclusters Confined within Hierarchical Porous Carbons with High Oxidation Activity
Zhao, Xin,Kong, Xiangpeng,Wang, Fengliang,Fang, Ruiqi,Li, Yingwei
supporting information, p. 10842 - 10849 (2021/03/16)
Metal sub-nanoclusters (SNCs) have shown great promise for a variety of catalytic reactions. However, the fabrication of stable metal SNCs simultaneously with high dispersion and high metal contents remains a challenge. Herein, we report a novel and versatile strategy for the synthesis of various bimetal SNCs stabilized within hierarchical porous carbons (HPC). This facile synthesis only involves the self-assembly of a metal-organic framework (MOF) as the precursor, a molten salt assisted pyrolysis process and the final metal replacement. The metal SNCs (mostly less than 0.8 nm) derived from the metal nodes of the MOF are exclusively confined and homogeneously dispersed throughout the organic ligands derived HPC at high loadings (up to 11.2 wt %). The obtained Cu-Pd@HPC composite exhibits superior catalytic activity and recycling durability in the selective transformation of furfural to maleic acid, achieving 97.8 % yield of maleic acid with a TOF value as high as 20.1 h?1 under mild conditions. DFT calculations reveal that the introduction of Pd shifts the partial density of states of Cu toward the Fermi level, leading to stronger chemisorption of furfural to enhance the catalytic activity.
