104-20-1Relevant articles and documents
Palladium Catalysis for Aerobic Oxidation Systems Using Robust Metal–Organic Framework
Li, Jiawei,Liao, Jianhua,Ren, Yanwei,Liu, Chi,Yue, Chenglong,Lu, Jiaming,Jiang, Huanfeng
, p. 17148 - 17152 (2019)
Described here is a new and viable approach to achieve Pd catalysis for aerobic oxidation systems (AOSs) by circumventing problems associated with both the oxidation and the catalysis through an all-in-one strategy, employing a robust metal–organic framework (MOF). The rational assembly of a PdII catalyst, phenanthroline ligand, and CuII species (electron-transfer mediator) into a MOF facilitates the fast regeneration of the PdII active species, through an enhanced electron transfer from in situ generated Pd0 to CuII, and then CuI to O2, trapped in the framework, thus leading to a 10 times higher turnover number than that of the homogeneous counterpart for Pd-catalyzed desulfitative oxidative coupling reactions. Moreover, the MOF catalyst can be reused five times without losing activity. This work provides the first exploration of using a MOF as a promising platform for the development of Pd catalysis for AOSs with high efficiency, low catalyst loading, and reusability.
Activity and selectivity of W110A secondary alcohol dehydrogenase from Thermoanaerobacter ethanolicus in organic solvents and ionic liquids: Mono- and biphasic media
Musa, Musa M.,Ziegelmann-Fjeld, Karla I.,Vieille, Claire,Phillips, Robert S.
, p. 887 - 892 (2008)
The asymmetric reduction of hydrophobic phenyl-ring-containing ketones and the enantiospecific kinetic resolution of the corresponding racemic alcohols catalyzed by Thermoanaerobacter ethanolicus W110A secondary alcohol dehydrogenase were performed in mono- and biphasic systems containing either organic solvents or ionic liquids. Both yield and enantioselectivity for these transformations can be controlled by changing the reaction medium. The enzyme showed high tolerance to both water-miscible and -immiscible solvents, which allows biotransformations to be conducted at high substrate concentrations. The Royal Society of Chemistry.
Synthesis of α-Tertiary Amine Derivatives by Intermolecular Hydroamination of Unfunctionalized Alkenes with Sulfamates under Trifluoromethanesulfonic Acid Catalysis
Fei, Jun,Wang, Zhen,Cai, Zheren,Sun, Hao,Cheng, Xu
, p. 4063 - 4068 (2015)
An efficient and mild trifluoromethanesulfonic acid-catalyzed hydroamination of unfunctionalized alkenes to afford α-tertiary amine derivatives at temperatures as low as room temperature is reported. 2,2,2-Trifluoroethyl sulfamate was found to be the optimal nitrogen source because its good solubility in both organic solvents and water facilitated both conversion and purification. The reaction conditions were compatible with a variety of substrate functional groups and afforded moderate to good yields. The desired amine compounds could be obtained easily by means of a mild, one-pot, redox-neutral deprotection procedure. Caryolane amine was synthesized with excellent chemo- and regioselectivities by means of a cascade hydroamination reaction of β-caryophyllene.
A scalable two-step continuous flow synthesis of nabumetone and related 4-aryl-2-butanones
Viviano, Monica,Glasnov, Toma N.,Reichart, Benedik,Tekautz, Guenter,Kappe, C. Oliver
, p. 858 - 870 (2011)
Three different continuous flow strategies for the generation of important 4-aryl-2-butanone derivatives including the anti-inflammatory drug nabumetone [4-(6-methoxy-2-naphthalenyl)-2-butanone] and the aroma compounds raspberry ketone [4-(4-hydroxyphenyl)-2-butanone] and its methyl ether [4-(4-methoxyphenyl)-2-butanone] were evaluated. All three protocols involve the initial preparation of the corresponding 4-aryl-3-buten-2-ones via Mizoroki-Heck, Wittig, or aldol strategies, which is then followed by selective hydrogenation of the C=C double bond to the desired 4-aryl-2-butanones. The synthetic routes to 4-aryl-3-buten-2-ones were first optimized/intensified on small scale to reaction times of 1-10 min using batch microwave heating technology and then translated to a scalable continuous flow process employing commercially available stainless steel capillary tube reactors. For the synthesis of 4-(4-methoxyphenyl)-3-buten-2-one a further scale-up using a custom-built mesofluidic mini-plant flow system capable of processing several liters per hour was designed to further expand the scale of the process. The final hydrogenation step was performed using a fixed-bed continuous flow hydrogenator employing Ra/Ni as a catalyst.
A chemoselective hydrogenation of the olefinic bond of α,β- unsaturated carbonyl compounds in aqueous medium under microwave irradiation
Sharma, Anuj,Kumar, Vinod,Sinha, Arun K.
, p. 354 - 360 (2006)
A microwave-assisted mild and ecofriendly catalytic transfer hydrogenation process was developed to reduce various α,β-unsaturated carbonyl compounds into the corresponding saturated carbonyl compounds in the presence of silica-supported palladium chloride as catalyst and a combination of MeOH/HCOOH/H2O (1:2:3) as hydrogen source within 22-55 minutes in moderate to excellent yields with 100% chemoselectivity.
Synthesis and neuroprotective evaluation of (E)-3,4-dihydroxystyryl p-substituted-phenethyl ketone derivatives against inflammatory and oxidative injury
Cheng, Can,Ning, Xianling,Luo, Yongming,Tian, Chao,Wang, Xiaowei,Guo, Ying,Liu, Junyi,Zhang, Zhili
, p. 1678 - 1685 (2016)
(E)-3,4-dihydroxystyryl p-substituted-phenethyl ketones and their 3,4-diacetylated derivatives were synthesized and examined their neuroprotective activities to further study the effect of p-substituents on the aromatic ring. The results revealed that steric hindrance effect of p-substituents has impact on neuroprotective activities against inflammatory and oxidative injury. Introduction of the bulkier groups are more beneficial to improve the neuroprotective activities than smaller groups. Compounds (4–5h, 4–5i and 4–5e) with p-substituted trifluoromethyl, isopropyl and t-butyl groups exhibited the best effects among all the target compounds.
H-type zeolite-catalyzed 1,4-addition of benzene derivatives to labile acrolein
Hayashi, Daijiro,Narisawa, Tomoyuki,Masui, Yoichi,Onaka, Makoto
, p. 460 - 471 (2016)
The 1,4-addition of benzene derivatives to acrolein is a straightforward way to synthesize 3-arylpropanals. A survey of acid catalysts for the 1,4-addition of methoxy-substituted benzenes to acrolein revealed that H-Beta and H-Y were the most suitable catalysts. We hypothesized three side-reactions: (1) the double 1,4-addition of acrolein to the starting benzene derivatives, (2) the Friedel-Crafts-type alkylation to the desired product, and (3) the self-polymerization of acrolein. The type (3) side-reaction was inhibited by two different methods which kept the concentration of acrolein low in the reaction mixture or in the zeolite pores. First, acrolein monomers were in situ generated through the gradual monomerization of an acrolein cyclic trimer. Second, using a reaction solvent lowered the acrolein concentration in the zeolite pores due to the competitive adsorption. We discovered that the content of monomeric acrolein in a solvent was closely related to the polarity of the solvent. Actually, both methods improved the yields for the 1,4-additions of 1,3-dimethoxybenzene to acrolein. Other electron-rich benzene derivatives, such as phenol and N, N-dimethylaniline, were also applicable to the 1,4-addition reactions.
Pd-aminoclay nanocomposite as an efficient recyclable catalyst for hydrogenation and suzuki cross coupling reactions
Kumar, A. Sravanth,Datta,Rao, T. Srinivasa,Raghavan,Eswaramoorthy,Reddy, B.V. Subba
, p. 2000 - 2007 (2012)
A highly water dispersible Pd-aminoclay nanocomposite is found to be effective catalytic system for the hydrogenation of α,β-unsaturated carbonyl compounds and Suzuki coupling reactions in aqueous media. The catalytic hydrogenation of α,β-unsaturated carbonyl compounds proceeds at room temperature to afford the corresponding products in excellent yields with high chemoselectivity. The cross coupling of aryl bromides and iodides with aryl boronic acids proceeds efficiently under aqueous conditions at 90 °C to afford the corresponding biaryls in excellent yields with high selectivity. The Suzuki reaction proceeds smoothly even in the absence of external base due to the basic nature of the catalyst support. The catalyst could be easily recovered and recycled three times without a significant loss of activity in hydrogenation and Suzuki cross coupling reactions. Copyright
Cobalt bromide as catalyst in electrochemical addition of aryl halides onto activated olefins
Gomes, Paulo,Gosmini, Corinne,Nédélec, Jean-Yves,Périchon, Jacques
, p. 3385 - 3388 (2000)
The consumable anode process permits the electrochemical arylation of activated olefins from functionalized aryl halides when cobalt halide is used as catalyst, either associated with bipyridine and pyridine as ligands in DMF as solvent, or with only pyridine in acetonitrile as solvent. (C) 2000 Published by Elsevier Science Ltd.
New synthesis of 1,4-diketones via rhodium-catalysed 1,4 carbonylative addition of arylboronic acids to α,β-unsaturated ketones
Sauthier, Mathieu,Castanet, Yves,Mortreux, Andre
, p. 1520 - 1521 (2004)
The reaction of various arylboronic acids with α,β-unsaturated ketones under CO pressure and in the presence of rhodium catalyst yields 1,4-diketones.
Palladium-catalyzed arylation of allylic alcohols with aryl iodides in water
Zhao,Cai,Hu,Song
, p. 3665 - 3669 (2001)
Palladium-catalyzed arylation of allylic alcohols with aryl iodides are shown to occur in the presence of sodium bicarbonate and tetra-n-butylammonium chloride in pure water using palladium acetate as catalyst. β-aromatic carbonyl compounds are obtained in good yields.
Carbonylative 1,4-addition of potassium aryltrifluoroborates to vinyl ketones
Sauthier, Mathieu,Lamotte, Nicolas,Dheur, Julien,Castanet, Yves,Mortreux, Andre
, p. 969 - 971 (2009)
Potassium aryltrifluoroborates have proven to be useful reagents for the carbonylative aroylation of vinyl ketones; this study broadens the scope of potassium aryltrifluoroborates in homogeneous catalysis and shows that the solvent can act as the proton s
8-Hydroxyquinolin-2(1H)-one analogues as potential β2-agonists: Design, synthesis and activity study
Xing, Gang,Zhi, Zhengxing,Yi, Ce,Zou, Jitian,Jing, Xuefeng,Yiu-Ho Woo, Anthony,Lin, Bin,Pan, Li,Zhang, Yuyang,Cheng, Maosheng
, (2021/07/19)
β2-Agonists that bind to plasmalemmal β2-adrenoceptors causing cAMP accumulation are widely used as bronchodilators in chronic respiratory diseases. Here, we designed and synthesized a group of 8-hydroxyquinolin-2(1H)-one analogues and studied their β2-agonistic activities with a cellular cAMP assay. Compounds B05 and C08 were identified as potent (EC50 2-agonists among the compounds tested. They behaved as partial β2-agonists in non-overexpressed HEK293 cells, and possessed rapid smooth muscle relaxant actions and long duration of action in isolated guinea pig tracheal strip preparations. In summary, B05 and C08 are β2-agonists with potential applicability in chronic respiratory diseases.
Iron powder and tin/tin chloride as new reducing agents of Meerwein arylation reaction with unexpected recycling to anilines
Abdelwahab, Ahmed B.,El-Sawy, Eslam R.,Kirsch, Gilbert
supporting information, p. 526 - 538 (2020/01/08)
Simple and rapid route for Meerwein arylation reaction using iron powder or a mixture of tin/tin chloride has been developed. In the presence of iron powder, different aryl diazonium salts reacted with methyl vinyl ketone, acrylates, and isopropenyl acetate. Production of oximes was detected as the main product with acrylates or in a mixture with β-aryl methyl ketones in the case of methyl vinyl ketone. The in situ produced HNO2 from an excess of NaNO2/HCl was trapped by alkyl aryl radical to form oximes in the E configuration form. The presence of tin/tin chloride mixture in the reaction of the aryl diazonium salts with methyl vinyl ketone produced Michael products along with β-aryl methyl ketones. The predicted α-aryl methyl ketones from the reaction of isopropenyl acetate with the diazotized anilines were obtained using iron or tin/tin chloride mixture.
One-Pot, Tandem Wittig Hydrogenation: Formal C(sp3)-C(sp3) Bond Formation with Extensive Scope
Devlin, Rory,Jones, David J.,Mcglacken, Gerard P.
supporting information, p. 5223 - 5228 (2020/07/14)
A one-pot, tandem Wittig hydrogenation of aldehydes with stabilized ylides is reported, representing a formal C(sp3)-C(sp3) bond construction. The tandem reaction operates under mild conditions, is high yielding, and is broad in scope. Chemoselectivity for olefin reduction is observed, and the methodology is demonstrated in the synthesis of lapatinib analogues and a formal synthesis of (±)-cuspareine. Early insights suggest that the chemoselectivity observed in the reduction step is due to partial poisoning of the catalyst, after step one, thus adding to the power of the one-pot procedure.
