527-72-0Relevant articles and documents
LIQUID-PHASE CATALYTIC OXIDATION OF 2-METHOXYMETHYLTHIOPHENE
Leichenko, A. A.,Schedrinskaya, T. V.,Volkov, M. N.
, p. 714 - 718 (1980)
The oxidation of 2-methoxymethylthiophene with molecular oxygen in the presence of a cobalt bromide catalyst in the kinetic region at 65-100 deg C was investigated.It is shown that the principal products are 2-formylthiophene and methylthiophene-2-carboxylate in a ratio of 1:2.The composition of the products does not depend on the oxidation temperature and changes as the starting concentration of 2-methoxymethylthiophene and the amount of cobalt bromide catalyst are changed.
The gas-phase elimination kinetics of ethyl 2-furoate and ethyl 2-thiophenecarboxylate
Espitia, Liliany,Meneses, Ruby,Dominguez, Rosa M.,Tosta, Maria,Herize, Armando,Lezama, Jesus,Lafont, Jennifer,Chuchani, Gabriel
, p. 145 - 152 (2009)
The gas-phase elimination kinetics of ethyl 2-furoate and 2-ethyl 2-thiophenecarboxylate was carried out in a static reaction system over the temperature range of 623.15-683.15 K (350-410°C) and pressure range of 30-113 Torr. The reactions proved to be ho
Facile production of vitamin B3 and other heterocyclic carboxylic acids using an efficient Ag/ZnO/graphene-Si hybrid nanocatalyst
Attia, Yasser A.,Vázquez, Carlos Vázquez,Mohamed, Yasser M. A.
, p. 203 - 218 (2017)
Abstract: High yield of vitamin B3 is produced using Ag/ZnO/graphene nanocomposite (1?wt%) as a nanocatalyst after its activation by a silicon precursor such as trimethylsilyl chloride(TMSCl) or tert-butyldimethylsilyl chloride (TBSCl) under visible light. TBSCl has been proved as more efficient activating agent than TMSCl in the oxidation of heterocyclic alcohol derivatives to afford their corresponding carboxylic acids. 3-Pyridinemethanol was selected to be a model substrate to test the ability of Ag/ZnO/graphene-Si nanocatalysts. The oxidation reaction of alcohols was completed in short reaction time (30–60?min) at ambient condition to yield vitamin B3 and other heterocyclic carboxylic acids in excellent yields (86–99?%). A catalytic oxidation mechanism that is based on the generation of highly active catalytic oxidation species (oxygen radicals) has been proposed. The utility of this inexpensive and recyclable catalytic system without using molecular oxygen or any oxidants make this procedure interesting from a green chemistry point of view. Graphical Abstract: [Figure not available: see fulltext.]
Photochemistry of diketones: Observation of a triplet state-oxygen adduct
Cosa, Gonzalo,Scaiano, Juan C.
, p. 8636 - 8637 (2004)
The presence of triplet state-oxygen adducts (a species previously proposed but never observed in a direct manner) is readily observed following laser flash photolysis studies of 2,2′-thenil. We report on the kinetic and spectroscopic parameters characteristic of this transient adduct. Copyright
Kinetics of the oxidation of heterocyclic aldehydes by quinolinium dichromate
Chaubey, Girija Shankar,Das, Simi,Mahanti, Mahendra Kumar
, p. 2215 - 2220 (2002)
Quinolinium dichromate in sulfuric acid oxidizes heterocyclic aldehydes (2-furaldehyde, 2-pyrrolecarbaldehyde, 2-thiophenecarbaldehyde) to the corresponding acids in a 50% (v/v) acetic acid-water medium. The kinetic data on the rates of oxidation of the substrates have been discussed with reference to the aldehyde hydration equilibria. The kinetic results support a mechanistic pathway proceeding via a rate-determining oxidative decomposition of the chromate ester of the aldehyde hydrate.
Palladium-promoted One-step Carboxylation of Aromatic Compounds with Carbon Monoxide
Fujiwara, Yuzo,Kawauchi, Tomio,Taniguchi, Hiroshi
, p. 220 - 221 (1980)
The one-step carboxylation of aromatic compounds such as benzene, toluene, anisole, chlorobenzene, furan, and thiophen has been carried out using carbon monoxide and palladium acetate; the reaction does not require oxygen and is electrophilic.
Structure and Mechanism of Pseudomonas aeruginosa PA0254/HudA, a prFMN-Dependent Pyrrole-2-carboxylic Acid Decarboxylase Linked to Virulence
Payne, Karl A. P.,Marshall, Stephen A.,Fisher, Karl,Rigby, Stephen E. J.,Cliff, Matthew J.,Spiess, Reynard,Cannas, Diego M.,Larrosa, Igor,Hay, Sam,Leys, David
, p. 2865 - 2878 (2021)
The UbiD family of reversible (de)carboxylases depends on the recently discovered prenylated-FMN (prFMN) cofactor for activity. The model enzyme ferulic acid decarboxylase (Fdc1) decarboxylates unsaturated aliphatic acids via a reversible 1,3-cycloaddition process. Protein engineering has extended the Fdc1 substrate range to include (hetero)aromatic acids, although catalytic rates remain poor. This raises the question how efficient decarboxylation of (hetero)aromatic acids is achieved by other UbiD family members. Here, we show that the Pseudomonas aeruginosa virulence attenuation factor PA0254/HudA is a pyrrole-2-carboxylic acid decarboxylase. The crystal structure of the enzyme in the presence of the reversible inhibitor imidazole reveals a covalent prFMN-imidazole adduct is formed. Substrate screening reveals HudA and selected active site variants can accept a modest range of heteroaromatic compounds, including thiophene-2-carboxylic acid. Together with computational studies, our data suggests prFMN covalent catalysis occurs via electrophilic aromatic substitution and links HudA activity with the inhibitory effects of pyrrole-2-carboxylic acid on P. aeruginosa quorum sensing.
Gram-scale synthesis of carboxylic acids via catalytic acceptorless dehydrogenative coupling of alcohols and hydroxides at an ultralow Ru loading
Chen, Cheng,Cheng, Hua,Verpoort, Francis,Wang, Zhi-Qin,Wu, Zhe,Yuan, Ye,Zheng, Zhong-Hui
, (2021/12/13)
Acceptorless dehydrogenative coupling (ADC) of alcohols and water/hydroxides is an emergent and graceful approach to produce carboxylic acids. Therefore, it is of high demand to develop active and practical catalysts/catalytic systems for this attractive transformation. Herein, we designed and fabricated a series of cyclometallated N-heterocyclic carbene-Ru (NHC-Ru) complexes via ligand tuning of [Ru-1], the superior complex in our previous work. Gratifyingly, gram-scale synthesis of carboxylic acids was efficiently enabled at an ultralow Ru loading (62.5 ppm) in open air. Moreover, effects of distinct ancillary NHC ligands and other parameters on this catalytic process were thoroughly studied, while further systematic studies were carried out to provide rationales for the activity trend of [Ru-1]-[Ru-7]. Finally, determination of quantitative green metrics illustrated that the present work exhibited superiority over representative literature reports. Hopefully, this study could provide valuable input for researchers who are engaging in metal-catalyzed ADC reactions.
Transformation of Thioacids into Carboxylic Acids via a Visible-Light-Promoted Atomic Substitution Process
Fu, Qiang,Liang, Fu-Shun,Lou, Da-Wei,Pan, Gao-Feng,Wang, Rui,Wu, Min,Xie, Kai-Jun
supporting information, p. 2020 - 2024 (2022/03/31)
A visible-light-promoted atomic substitution reaction for transforming thiocacids into carboxylic acids with dimethyl sulfoxide (DMSO) as the oxygen source has been developed, affording various alkyl and aryl carboxylic acids in over 90% yields. The atomic substitution process proceeds smoothly through the photochemical reactivity of the formed hydrogen-bonding adduct between thioacids and DMSO. A DMSO-involved proton-coupled electron transfer (PCET) and the simultaneous generation of thiyl and hydroxyl radicals are proposed to be key steps for realizing the transformation.
Mechanochemical Grignard Reactions with Gaseous CO2 and Sodium Methyl Carbonate**
Pfennig, Victoria S.,Villella, Romina C.,Nikodemus, Julia,Bolm, Carsten
supporting information, (2022/01/22)
A one-pot, three-step protocol for the preparation of Grignard reagents from organobromides in a ball mill and their subsequent reactions with gaseous carbon dioxide (CO2) or sodium methyl carbonate providing aryl and alkyl carboxylic acids in up to 82 % yield is reported. Noteworthy are the short reaction times and the significantly reduced solvent amounts [2.0 equiv. for liquid assisted grinding (LAG) conditions]. Unexpectedly, aryl bromides with methoxy substituents lead to symmetric ketones as major products.