- Cu-Catalyzed Synthesis of Benzoxazole with Phenol and Cyclic Oxime
-
A Cu-catalyzed straightforward synthesis of benzoxazoles from free phenols and cyclic oxime esters is reported. The mild reaction conditions tolerate various electron-withdrawing and electron-donating functional groups on both substrates, affording benzoxazoles in moderate to good yields. With this protocol, large-scale syntheses of Ezutromid and Flunoxaprofe in one or two steps are demonstrated. A catalytic mechanism, which includes Cu-catalyzed amination via inner-sphere electron transfer and consequent annulation, is proposed.
- Wang, Zheng-Hai,Wang, Dong-Hui
-
supporting information
p. 782 - 785
(2022/01/20)
-
- Enantioselective decarboxylative Mannich reaction of β-keto acids withC-alkynylN-BocN,O-acetals: access to chiral β-keto propargylamines
-
The chiral keto-substituted propargylamines are an essential class of multifunctional compounds in the field of organic and pharmaceutical synthesis and have attracted considerable attention, but the related synthetic approaches remain limited. Therefore, a concise and efficient method for the enantioselective synthesis of β-keto propargylaminesviachiral phosphoric acid-catalyzed asymmetric Mannich reaction between β-keto acids andC-alkynylN-BocN,O-acetals as easily availableC-alkynyl imine precursors has been demonstrated here, affording a broad scope of β-ketoN-Boc-propargylamines in high yields (up to 97%) with generally high enantioselectivities (up to 97?:?3 er).
- Chen, Li-Jun,Li, Wei,Shen, Bao-Chun,Sun, Zhong-Wen,Xie, Hui-Ding,Zhang, Cong-Cong
-
supporting information
p. 8607 - 8612
(2021/10/20)
-
- Access to pyridines via cascade nucleophilic addition reaction of 1,2,3-triazines with activated ketones or acetonitriles
-
We studied the cascade nucleophilic addition reactions of 1,2,3-triazines with activated acetonitriles or ketones, which were used to construct highly substituted pyridines that are not easily accessed by conventional methods. The strategy addressed some structural diversity issues currently facing medicinal chemistry, and the resulting pyridines could be used as convenient precursors for the synthesis of related pharmaceuticals. In particular, our method was applied to the syntheses of the marketed drug etoricoxib and several biologically important molecules in a few steps.
- Zhang, Yuan,Luo, Han,Lu, Qixing,An, Qiaoyu,Li, You,Li, Shanshan,Tang, Zongyuan,Li, Baosheng
-
supporting information
p. 393 - 396
(2020/05/18)
-
- Photoinduced Diverse Reactivity of Diazo Compounds with Nitrosoarenes
-
A diverse reactivity of diazo compounds with nitrosoarene in an oxygen-transfer process and a formal [2 + 2] cycloaddition is reported. Nitosoarene has been exploited as a mild oxygen source to oxidize an in situ generated carbene intermediate under visible-light irradiation. UV-light-mediated in situ generated ketenes react with nitosoarenes to deliver oxazetidine derivatives. These operationally simple processes exemplify a transition-metal-free and catalyst-free protocol to give structurally diverse α-ketoesters or oxazetidines.
- Roy, Sourav,Kumar, Gourav,Chatterjee, Indranil
-
supporting information
p. 6709 - 6713
(2021/09/08)
-
- Chiral Vanadyl(V) Complexes Enable Efficient Asymmetric Reduction of β-Ketoamides: Application toward (S)-Duloxetine
-
High-valent chiral oxidovanadium(V) complexes derived from 3,5-substituted-N-salicylidene-l-tert-leucine were used as catalysts in asymmetric reduction of N-benzyl-β-ketoamides. Among six different solvents, three different alcohol additives, and two different boranes examined, the use of pinacolborane in tetrahydrofuran (THF) with a t-BuOH additive led to the best results at -20 °C. The corresponding β-hydroxyamides can be furnished with yields up to 92percent and an enantiomeric excess (ee) up to 99percent. We have successfully extended this catalytic protocol for the synthesis of an (S)-duloxetine precursor.
- Chen, Chien-Tien,Maity, Nabin Ch.,Agarwal, Rachit,Lai, Chien-Fu,Liao, Yiya,Yu, Wei-Ru
-
supporting information
p. 6408 - 6419
(2020/07/14)
-
- Noncanonical cation-π cyclizations of alkylidene β-ketoesters: Synthesis of spiro-fused and bridged bicyclic ring systems
-
Three cation-π cyclization cascades initiated at alkylidene β-ketoesters bearing pendent alkenes are described. Depending upon the alkene substitution pattern and the reaction conditions employed, it is possible to achieve selective synthesis of the three different types of products, including 1-halo-3-carbomethoxycyclohexanes, spiro-fused tricyclic systems, and [4.3.1] bridged bicyclic ring systems. All three reactions begin with 6-endo addition of an olefin to the alkylidene β-ketoester electrophile, followed by one of three different cation capture events.
- Parsons, Dylan E.,Frontier, Alison J.
-
supporting information
p. 2008 - 2012
(2019/03/26)
-
- TBHP/AIBN-Mediated Synthesis of 2-Amino-thioazoles from Active Methylene Ketones and Thiourea under Metal-free Conditions
-
A new oxidative system of tert-butyl hydroperoxide (TBHP)/azodiisobutyronitrile (AIBN) has been used for the first time for a convenient, metal-free synthesis of substituted 2-aminothioazoles from active methylene ketone derivatives and thiourea. The reaction is postulated to proceed via an oxidative cyclization initiated by a radical process and followed by a condensation reaction.
- Sun, Jiyun,Ge, Huaibin,Zhen, Xiaohua,An, Xuechan,Zhang, Guangtao,Zhang-Negrerie, Daisy,Du, Yunfei,Zhao, Kang
-
p. 2107 - 2114
(2018/03/26)
-
- Synthesis of trifluoromethylated 2H-azirines through Togni reagent-mediated trifluoromethylation followed by PhIO-mediated azirination
-
The reaction of enamine compounds with the Togni reagent in the presence of CuI afforded β-trifluoromethylated enamine intermediates, which were converted directly to biologically interesting trifluoromethylated 2H-azirines by an iodosobenzene (PhIO)-mediated intramolecular azirination in a one-pot process.
- Sun, Jiyun,Zhen, Xiaohua,Ge, Huaibin,Zhang, Guangtao,An, Xuechan,Du, Yunfei
-
supporting information
p. 1452 - 1458
(2018/07/05)
-
- Nickel-catalyzed enantioselective hydrogenation of β-(acylamino)acrylates: Synthesis of chiral β-amino acid derivatives
-
The nickel-catalyzed asymmetric hydrogenation of β-(acylamino)acrylates has been developed, affording chiral β-amino acid derivatives with excellent yields (95-99% yield) and enantioselectivities (97-99% ee). With the Ni-Binapine system, high enantioselectivities (98-99% ee) have also been obtained in the hydrogenation of Z/E isomeric mixtures of β-alkyl and β-aryl β-(acylamino)acrylates. The synthesis of chiral β-amino acid derivatives on a gram scale has also been achieved with 0.2 mol % catalyst loading.
- Li, Xiuxiu,You, Cai,Li, Shuailong,Lv, Hui,Zhang, Xumu
-
supporting information
p. 5130 - 5133
(2017/11/06)
-
- Copper-Catalysed Decarboxylative Trifluoromethylation of β-Ketoacids
-
An efficient method for Cu-catalyzed decarboxylative trifluoromethylation of β-ketoacids to achieve α-trifluoromethyl ketones was developed. A wide variety of synthetically useful α-trifluoromethyl ketones were obtained in modest to good yields under mild reaction conditions. The present method also exhibits good functional-group compatibility.
- Xu, Xiaolan,Chen, Huanhuan,He, Jianbo,Xu, Huajian
-
supporting information
p. 1665 - 1668
(2017/10/05)
-
- A palladium-catalyzed carbonylative-deacetylative sequence to 1,3-Keto Amides
-
An efficient three-component reaction involving carbon monoxide with a range of aryl bromides and N-substituted acetoacetamides is reported for the synthesis of b-keto amides. This transformation is promoted by Pd-catalysis followed by an acid-mediated deacetylation upon work-up, enabling a large number of b-keto amides to be isolated. Finally, d2-13C-dyclonine could be synthesized in three steps utilizing the developed catalytic system as the key step.
- Nielsen, Dennis U.,Korsager, Signe,Lindhardt, Anders T.,Skrydstrup, Troels
-
p. 3519 - 3524
(2015/01/09)
-
- A palladium-catalyzed carbonylative-deacetylative sequence to 1,3-keto amides
-
An efficient three-component reaction involving carbon monoxide with a range of aryl bromides and N-substituted acetoacetamides is reported for the synthesis of b-keto amides. This transformation is promoted by Pd-catalysis followed by an acid-mediated deacetylation upon work-up, enabling a large number of b-keto amides to be isolated. Finally, d2-13C-dyclonine could be synthesized in three steps utilizing the developed catalytic system as the key step.
- Nielsen, Dennis U.,Korsager, Signe,Lindhardt, Anders T.,Skrydstrup, Troels
-
supporting information
p. 3519 - 3524
(2015/01/09)
-
- Base initiated aromatization/CO bond formation: A new entry to O-pyrazole polyfluoroarylated ethers
-
A base initiated intermolecular SNAr reaction of pyrazolones with polyfluoroarenes was developed. The process involved the isomerization aromatization of pyrazolone followed by the CO bond formation via the selective CF bond cleavage. With this strategy, a wide range of O-pyrazole polyfluoroarylated ethers bearing diverse functional groups were synthesized in mild to good yields. Additionally, our method was also applied to the isoxazol substrates.
- Tang, Xiangyang,Chang, Jing,Liu, Cuibo,Zhang, Bin
-
supporting information
p. 6534 - 6537
(2015/01/08)
-
- Nickel-catalyzed asymmetric transfer hydrogenation of olefins for the synthesis of α- And β-amino acids
-
The field of asymmetric (transfer) hydrogenation of prochiral olefins has been dominated by noble metal catalysts based on rhodium, ruthenium, and iridium. Herein we report that a simple nickel catalyst is highly active in the transfer hydrogenation using
- Yang, Peng,Xu, Haiyan,Zhou, Jianrong
-
supporting information
p. 12210 - 12213
(2016/02/18)
-
- Diketopyrrolopyrrole-based sensitizers for dye-sensitized solar cell applications: Anchor engineering
-
A series of donor-chromophore-anchor (D-C-A) sensitizers comprising the diketopyrrolopyrrole (DPP) chromophore were synthesized and tested in both I3-/I- and Co[(bpy)]3+/2+ redox shuttle DSC devices. The dye ser
- Holcombe, Thomas W.,Yum, Jun-Ho,Kim, Yongjoo,Rakstys, Kasparas,Graetzel, Michael
-
p. 13978 - 13983
(2013/11/06)
-
- Synthesis, structure, absorption and fluorescence of Pechmann dye heteroanalogues
-
Three N-analogues of Pechmann dye with identical aryl groups in the 5, 5′-positions (aryl = phenyl, 2-naphthyl, 2-thienyl) and carboxy ester groups in the 3,3′-positions were synthesized by oxidative dimerization of the corresponding 5-aryl-pyrrolinone es
- Aysha, Tarek,Luňák Jr., Stanislav,Ly?ka, Antonín,Vyňuchal, Jan,Eliá?, Zdeněk,R??i?ka, Ale?,Padělková, Zdeňka,Hrdina, Radim
-
p. 530 - 539
(2013/07/27)
-
- A new mild method for the C-acylation of ketone enolates. a convenient synthesis of β-keto-esters,-thionoesters, and-thioesters
-
A new method for ketone enolate C-acylation is described which utilizes alkyl pentafluorophenylcarbonates, thiocarbonates, and thionocarbonates as the reactive acylating agents, and MgBr2·Et2O, DMAP, and i-Pr2NEt as the reagents for enolization. A wide range of ketones have been observed to undergo clean C-acylation via this protocol.
- Hale, Karl J.,Grabski, Milosz,Flasz, Jakub T.
-
supporting information
p. 370 - 373
(2013/03/13)
-
- HOTf mediated cascade reactions of 1-arenoylcyclopropanecarboxylic acids with arenes
-
The cascade reactions of 1-arenoylcyclopropanecarboxylic acids with arenes proceed smoothly in freshly distilled HOTf to give the corresponding tetrahydro-5H-benzo[c]fluorene derivatives in good yields along with high stereoselectivities under mild conditions. The Royal Society of Chemistry.
- Chen, Gen-Qiang,Tang, Xiang-Ying,Shi, Min
-
supporting information; scheme or table
p. 2340 - 2342
(2012/04/18)
-
- Protocol for the synthesis of heteroaromatic ring-Fused cyclohexanones
-
A general protocol for the catalytic homo-Nazarov cyclization of cyclopropyl heteroaryl ketones has been developed,which employs indiumtriflate as the promoter. A range of heteroaromatic ring-fused cyclohexanones was synthesized in 56-91% yield using this
- Phun, Lien H.,Patil, Dadasaheb V.,Cavitt, Marchello A.,France, Stefan
-
supporting information; scheme or table
p. 1952 - 1955
(2011/06/25)
-
- PYRROLOPYRROLE DERIVATIVES, THEIR MANUFACTURE AND USE AS SEMICONDUCTORS
-
The present invention relates to compounds of the formula (I) wherein the substituents are as defined in claim 1, and their use as organic semiconductor in organic devices, like diodes, organic field effect transistors and/or solar cells. The compounds of the formula I have excellent solubility in organic solvents. High efficiency of energy conversion, excellent field-effect mobility, good on/off current ratios and/or excellent stability can be observed, when said compounds are used in semiconductor devices or organic photovoltaic (PV) devices (solar cells).
- -
-
Page/Page column 57
(2010/11/03)
-
- Highly enantioselective synthesis of β-amino acid derivatives by the lewis base catalyzed hydrosilylation of β-enamino esters
-
A study was conducted to demonstrate highly enantioselective synthesis of β-amino acid derivatives by the Lewis base catalyzed hydrosilylation of βenamino esters. It was found that these catalyst and its analogue displayed excellent activities and enantioselectivities in promoting hydrosilylation of N-aryl β-enamino esters. N-picolinoylpyrrolidine derivatives and N-picolioylephedrine were also evaluated in hydrosilylation of (Z)-methyl 3-phenyl-3-(phenylamino)acrylate. The generality of the Lewis base organocatalyzed hydrosilylation of various β-enamino esters were examined under the optimized conditions. It was observed that the catalytic system exhibited a high sensitivity to the N-substituents, while all the N-aryl β-enamino esters underwent the hydrosilylation smoothly to give corresponding β-amino esters.
- Zheng, Hong-Jie,Chen, Wen-Bing,Wu, Zhi-Jun,Deng, Jin-Gen,Lin, Wen-Qing,Yuan, Wei-Cheng,Zhang, Xiao-Mei
-
supporting information; experimental part
p. 9864 - 9867
(2009/10/02)
-
- Enantioselective Hydrogenation of β-Keto Esters using Chiral Diphosphine-Ruthenium Complexes: Optimization for Academic and Industrial Purposes and Synthetic Applications
-
Enantioselective hydrogenation using chiral complexes between atropisomeric diphosphines and ruthenium is a powerful tool for producing chiral compounds. Using a simple and straightforward in situ catalyst preparation, the conditions were optimized using molecular hydrogen for both academic and industrial purposes. This led to the best conditions and the lowest catalytic ratio required for the pressure used. Hydrogenation of various β-keto esters was efficiently performed at atmospheric and higher pressures, leading to the use of very low catalyst-substrate ratios up to 1/20,000. Asymmetric hydrogenations were used in key-steps towards the total synthesis of corynomycolic acid, Duloxetine and Fluoxetine.
- Ratovelomanana-Vidal,Girard,Touati,Tranchier,Ben Hassine,Genet
-
p. 261 - 274
(2007/10/03)
-
- Process for preparing arylaminopropanols
-
The invention relates to a process for preparing enantiomerically enriched aryl-aminopropanols and to their use and also to intermediates.
- -
-
-
- Improved gelatinase a selectivity by novel zinc binding groups containing galardin derivatives
-
The synthesis of several analogues of galardin, a MMP inhibitor, are presented with their in vitro inhibitory activity against MMP-1 and MMP-2. These compounds contain a distinct Zinc Binding Group (ZBG). Those having a 2-acylated-heterocycle as well as a 2-arylamide function do not exhibit a good inhibition/selectivity against the enzymes tested. On the contrary, those that are based on a hydrazide scaffold present potent selectivity for MMP-2 versus MMP-1.
- Auge, Franck,Hornebeck, William,Decarme, Martine,Laronze, Jean-Yves
-
p. 1783 - 1786
(2007/10/03)
-
- Controlled synthesis of functionalized mixed thiophene/furan oligomers
-
A novel and simple synthetic route for the preparation of a series of functionalized mixed thiophene/furan oligomers is described. This method, involving a Mn(OAc)3-mediated oxidative addition βthienyl-β-keto esters (=βoxothiophenepropanoates) to methyl 3-thienylprop-2-enoates, allows the construction of highly functionalized heteropolyaromatic oligomers possessing various chain lengths (Schemes 2, 4, and 5). Moreover, the straightforward transformation of the carbonyl functions appended to the furan rings leads to polycarboxylic acid precursors of H2O-soluble conducting polymers (Scheme 6).
- Garzino, Frederic,Meou, Alain,Brun, Pierre
-
p. 1989 - 1998
(2007/10/03)
-
- Ketone derivatives and medical application thereof
-
The present invention relates to ketone derivatives represented by the following formula and medical agents containing the ketone derivatives or pharmacologically acceptable salts thereof as an active ingredient, and in particular, relates to a hematopoietic agent; it is shown that the present invention increases blood cells, such as platelets, white blood cells, and red blood cells, and is effective in preventing and treating cytopenia caused by cancer chemotherapy, radiation therapy, and the like.
- -
-
-