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Relevant bibliographies by topics / Trifluoromethyl Ketones

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Academic literature on the topic 'Trifluoromethyl Ketones'

Author: Grafiati

Published: 4 June 2021

Last updated: 6 February 2022

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Journal articles on the topic "Trifluoromethyl Ketones"

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Yamaguchi, Eiji, Akichika Itoh, Yuji Kamito, Kazuki Matsuo, and Jun Ishihara. "Photooxidative Keto-Trifluoromethylation of Styrenes by Means of an Anthraquinone-Based Organocatalyst." Synthesis 50, no. 16 (2018): 3161–68. http://dx.doi.org/10.1055/s-0036-1592003.

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α-Trifluoromethyl ketones are versatile building blocks for the synthesis of various trifluoromethyl-functionalized molecules. Although there are significant advantages in the development of methods toward direct transformations of styrenes into α-trifluoromethyl ketones, most procedures leading to α-trifluoromethyl ketones require heavy- or transition-metal-based complexes. Herein, a novel method is developed for the synthesis of α-trifluoromethyl ketones via anthraquinone-catalyzed photooxidative keto-trifluoromethylation of styrenes with the readily available Langlois reagent (CF3SO2Na) und

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Wu, Wei, and Zhiqiang Weng. "Synthesis of Aryl Trifluoromethyl Ketones." Synthesis 50, no. 10 (2018): 1958–64. http://dx.doi.org/10.1055/s-0036-1591971.

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Trifluoromethyl ketones have recently been attracting considerable attention because they represent powerful synthetic building blocks with potential pharmaceutical applications. This short review provides an overview of recent development in the synthesis of aryl trifluoromethyl ketones with novel reagents.1 Introduction2 Various Methods for the Synthesis of Aryl Trifluoromethyl Ketones2.1 Oxidation of Trifluoromethyl Alcohols2.2 Nucleophilic Trifluoromethylation Reactions2.3 Electrophilic-Type Reactions2.4 Recently Developed Direct Trifluoroacetylation3 Conclusions

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He, Lin, Zhi-Hua Cai, Ji-Xin Pian та Guang-Fen Du. "NHCs Catalyzed Hydrophosphonylation ofα-Ketoesters andα-Trifluoromethyl Ketones". Scientific World Journal 2013 (2013): 1–6. http://dx.doi.org/10.1155/2013/890187.

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N-Heterocyclic carbenes catalyzed hydrophosphonylation reaction ofα-ketoesters andα-trifluoromethyl ketones was developed. Under the catalysis of 10 mol% IPr,α-ketoesters orα-trifluoromethyl ketones reacted with dialkyl phosphites to provide quaternaryα-hydroxyphosphonates in good to excellent yield.

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Dobson, Luca S., and Graham Pattison. "Rh-Catalyzed arylation of fluorinated ketones with arylboronic acids." Chemical Communications 52, no. 74 (2016): 11116–19. http://dx.doi.org/10.1039/c6cc05775f.

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Kudalkar, Gaurav P., Virendra K. Tiwari, Joshua D. Lee, and David B. Berkowitz. "A Hammett Study of Clostridium acetobutylicum Alcohol Dehydrogenase (CaADH): An Enzyme with Remarkable Substrate Promiscuity and Utility for Organic Synthesis." Synlett 31, no. 03 (2020): 237–47. http://dx.doi.org/10.1055/s-0039-1691576.

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Described is a physical organic study of the reduction of three sets of carbonyl compounds by the NADPH-dependent enzyme Clostridium acetobutylicum alcohol dehydrogenase (CaADH). Previous studies in our group have shown this enzyme to display broad substrate promiscuity, yet remarkable stereochemical fidelity, in the reduction of carbonyl compounds, including α-, β- and γ-keto esters (d-stereochemistry), as well as α,α-difluorinated-β-keto phosphonate esters (l-stereochemistry). To better mechanistically characterize this promising dehydrogenase enzyme, we report here the results of a Hammett

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Bégué, Jean-Pierre, and Danièle Bonnet-Delpon. "Preparation of trifluoromethyl ketones and related fluorinated ketones." Tetrahedron 47, no. 20-21 (1991): 3207–58. http://dx.doi.org/10.1016/s0040-4020(01)86391-2.

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Zhang, Dongxin, and Fujie Tanaka. "Catalytic enantioselective oxa-hetero-Diels–Alder reactions of enones with aryl trifluoromethyl ketones." RSC Advances 6, no. 66 (2016): 61454–57. http://dx.doi.org/10.1039/c6ra13859d.

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Asymmetric oxa-hetero-Diels–Alder reactions of enones with aryl trifluoromethyl ketones were developed to afford tetrahydropyranones bearing trifluoromethyl-substituted tetrasubstituted carbon centers.

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Feng, X., X. Zhou, Q. Zhang, et al. "Asymmetric Hydrophosphonylation of Trifluoromethyl Ketones." Synfacts 2011, no. 01 (2010): 0056. http://dx.doi.org/10.1055/s-0030-1258987.

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Linderman, Russell J., and Madhu S. Lonikar. "The synthesis of unsaturated trifluoromethyl ketones by regioselective organocuprate addition to acetylemic trifluoromethyl ketones." Tetrahedron Letters 28, no. 44 (1987): 5271–74. http://dx.doi.org/10.1016/s0040-4039(00)96705-4.

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Wang, Jingjing, Wei-Guang Kong, Feng Li, et al. "Silver salts and DBU cooperatively catalyzed nucleophilic addition/cyclization of propargylic alcohols with trifluoromethyl ketones." Organic & Biomolecular Chemistry 13, no. 19 (2015): 5399–406. http://dx.doi.org/10.1039/c5ob00438a.

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A general and efficient synthesis of trifluoromethyl substituted 5-alkylidene-1,3-dioxolane using a silver salt and DBU cooperatively catalyzed nucleophilic addition/cyclization of propargylic alcohols and trifluoromethyl ketones is described.

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Dissertations / Theses on the topic "Trifluoromethyl Ketones"

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Camerino, Eugene. "Trifluoromethyl ketones: Potential insecticides towards Anopheles gambiae." Thesis, Virginia Tech, 2013. http://hdl.handle.net/10919/54015.

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Malaria continues to cause significant mortality in sub-Saharan Africa and elsewhere, and existing vector control measures are being threatened by growing resistance to pyrethroid insecticides. With the goal of developing new human-safe, resistance-breaking insecticides we have explored several classes of acetylcholinesterase inhibitors. In vitro assay studies have shown that trifluoromethyl ketones (TFK\'s) are potent inhibitors of An. gambiae AChE (AgAChE), that inhibit the enzyme by making a covalent adduct with the catalytic serine of the enzyme. However research in the Carlier group ha

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Belletti, Giada. "Organocatalytic Enantioselective Vinylogous Aldol-Lactonization Cascade Reaction of 3-Alkylidene Oxindoles to Trifluoromethyl Ketones." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amslaurea.unibo.it/14463/.

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In this work, an highly enantioselective vinylogous aldol-lactonization cascade reaction of 3-alkylidene oxindole to α,β-unsaturated trifluoromethyl ketone, promoted by bifunctional organocatalysts, is presented. The reaction proceed through 1,2-addition followed by cascade lactonization to afford an unsaturated lactone bearing a chiral trifluoromethylated tetrasubstituted carbon stereocenter with high enantioselectivity and moderate yield. Nevertheless, also the two E/Z isomers of the correspondent 1,2-addition product are obtained.

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Fager, Diana Catherine. "Catalytic Enantioselective Additions of Allyl Moieties to α-Halomethyl Ketones, Trifluoromethyl Substituted NH-Ketimines, and Nitriles:". Thesis, Boston College, 2020. http://hdl.handle.net/2345/bc-ir:108931.

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Thesis advisor: Amir H. Hoveyda<br>Homoallylic alcohols and amines are commonly used building blocks for synthesis of biologically active molecules, yet a survey of the methods for their synthesis reveals a plague of limitations. Notably, the use of toxic reagents (Cr-, Mn-, and Sn-containing), precious metal catalysts (Ir- and In-based), non-ambient reaction temperatures (–78 to 140 °C), and extended reaction times (up to 240 hours), limit application on larger scale. The protection/deprotection sequences required to install directing/activating groups for reaction efficiency and enantioselec

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Ditch, Benjamin D. "Thermal decomposition products testing with 1,1,1,2,2,4,5,5,5 nonafluoro-4-trifluoromethyl pentan-3-one (C6 F-ketone) during fire extinguishing." Link to electronic thesis, 2003. http://www.wpi.edu/Pubs/ETD/Available/etd-0106103-152708.

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Camerino, Eugene. "Fluoromethyl ketone prodrugs: Potential new insecticides towards Anopheles gambiae." Diss., Virginia Tech, 2015. http://hdl.handle.net/10919/73771.

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Malaria continues to cause significant mortality in sub-Saharan Africa and elsewhere, and existing vector control measures are being threatened by growing resistance to pyrethroid insecticides. With the goal of developing new human-safe, resistance-breaking insecticides we have explored several classes of acetylcholinesterase inhibitors. In vitro assay studies demonstrate that tri- and difluoromethyl ketones can potentially inhibit An. gambiae AChE (AgAChE). These compounds inhibit the enzyme by making a covalent adduct with the catalytic serine of AChE. Trifluoromethyl ketones however are

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Garcia, Fábio Dutra. "Novos Espirocromenil-Trifluoretanonas a partir de Reações de Trifluoracetilação de Adutos de Kabbe e seus Espiro[diidrocromeno-cicloalcan]pirazóis e Isoxazóis Derivados." Universidade Federal de Santa Maria, 2013. http://repositorio.ufsm.br/handle/1/10564.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior<br>This work describes firstly an efficient and regioselective method for the synthesis of a new series of 2,2,2-trifluoro-1-[4-methoxy-spiro(2H-chromen-2,1 -cycloalkan)-3-yl]ethanones from the Kabbe adducts (spiro[chroman-2,1 -cycloalkan]-4-ones). Yields of 38 % to 61 % were obtained when trifluoroacetylation reactions of mixtures of enolethers and/or acetals derived from four spiro ketones (Kabbe adducts) were performed at a temperature of 45 oC and employing anhydrous chloroform as the solvent. Subsequently, when the respective tri

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Shao, Yi-Ming. "Design, Synthesis, Biological Activity, and Complexed Structure of SARS-CoV 3CL Protease Inhibitors: (i) Trifluoromethyl Ketones and (ii) C2-Symmetric Diols." 2006. http://www.cetd.com.tw/ec/thesisdetail.aspx?etdun=U0001-1106200616003800.

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Shao, Yi-Ming, and 邵奕鳴. "Design, Synthesis, Biological Activity, and Complexed Structure of SARS-CoV 3CL Protease Inhibitors:(i) Trifluoromethyl Ketones and (ii) C2-Symmetric Diols." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/65964005844513550816.

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碩士<br>國立臺灣大學<br>生化科學研究所<br>94<br>Severe acute respiratory syndrome (SARS) is a new viral infectious disease caused by a novel coronavirus (SARS-CoV). Currently, no effective antiviral agents exist against this type of virus. This thesis comprises the design, synthesis, biological activity, and complexed structures of two types of small molecules as inhibitors of SARS-CoV 3CL protease: (i) trifluoromethyl ketones and (ii) C2-symmetric diols. Trifluoromethyl ketones are known to be reversible inhibitors of some serine proteases, such as elastase and chymotrypsin. The best one of a series o

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Books on the topic "Trifluoromethyl Ketones"

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Nenajdenko, Valentine G. Chemistry of [alpha], [beta]-unsaturated trifluoromethly [i.e. trifluoromethyl] ketones. Nova Science Publishers, Inc., 2007.

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Book chapters on the topic "Trifluoromethyl Ketones"

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Aubert, Corinne, Jean-Pierre Bégué, Danièle Bonnet-Delpon, and Dany Mesureur. "Access to Trifluoromethyl Indans by Cycloalkylation of β-Aryl Trifluoromethyl-Ketones." In Selectivities in Lewis Acid Promoted Reactions. Springer Netherlands, 1989. http://dx.doi.org/10.1007/978-94-009-2464-2_16.

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Székács, András, Barna Bordás, György Matolcsy, and Bruce D. Hammock. "Quantitative Structure—Activity Relationship Study of Aromatic Trifluoromethyl Ketones." In ACS Symposium Series. American Chemical Society, 1989. http://dx.doi.org/10.1021/bk-1989-0413.ch012.

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Suffert, J. "Synthesis from Trifluoromethyl Ketones via Fluorinated Silyl Enol Ethers." In Ketones. Georg Thieme Verlag KG, 2005. http://dx.doi.org/10.1055/sos-sd-026-00770.

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Hof, K., K. M. Lippert, and P. R. Schreiner. "Michael Addition of α-Cyano Ketones to α,β-Unsaturated Trifluoromethyl Ketones." In Brønsted Base and Acid Catalysts, and Additional Topics. Georg Thieme Verlag KG, 2012. http://dx.doi.org/10.1055/sos-sd-205-00213.

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Tidwell, T. T. "Trifluoromethyl Ketones and Oxo Esters by Acylation of Monoalkylketenes with Trifluoroacetic Anhydride." In Three Carbon-Heteroatom Bonds: Thio-, Seleno-, and Tellurocarboxylic Acids and Derivatives; Imidic Acids and Derivatives; Ortho Acid Derivatives. Georg Thieme Verlag KG, 2006. http://dx.doi.org/10.1055/sos-sd-023-00569.

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Il'chenko, A. Y. "Additions of (Trifluoromethyl)phosphines and (Trifluoromethyl)phosphoranes to Alkenes, and Wittig Reactions of (Halomethyl)phosphonium Bromides with Aldehydes or Ketones." In Four Carbon-Heteroatom Bonds. Georg Thieme Verlag KG, 2005. http://dx.doi.org/10.1055/sos-sd-018-01406.

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Nacsa, Eric D., and Tristan H. Lambert. "Oxidation." In Organic Synthesis. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780190646165.003.0006.

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Huanfeng Jiang at the South China University of Technology developed (J. Am. Chem. Soc. 2013, 135, 5286) the palladium-catalyzed dehydrogenative aminohalogenation of methyl acrylate with aniline 1. A 1,3-hydrogen shift/ chlorination catalyzed by an iridium complex was reported (Angew. Chem. Int. Ed. 2013, 52, 6273) by Belén Martín- Matute at Stockholm University. Robert M. Waymouth discovered (J. Am. Chem. Soc. 2013, 135, 7593) the chemoselective oxidation of polyol 5 by a cationic palladium species. A ruthenium(II) hydride was found to catalyze the conversion of alcohols such as 7 to carboxylic acids using water as the oxygen source as disclosed (Nature Chem. 2013, 5, 122) by David Milstein at the Weizmann Institute of Science in Israel. Susan K. Hanson at the Los Alamos National Laboratory in New Mexico reported (Org. Lett. 2013, 15, 650) the acceptorless dehydrogenation of alcohols catalyzed by cobalt complex 12 to form imines such as 13 upon reaction with an amine. A collaboration led by Pedro J. Pérez at the University of Huelva in Spain studied (J. Am. Chem. Soc. 2013, 135, 3887) the oxidation of alkanes under catalysis with copper complex 15, primarily yielding alcohols and ketones, such as in the conversion of cyclohexane (14) to cyclohexanol (16) and cyclohexanone (17). A remarkable symmetry-breaking Wacker oxidation of diene 18 to produce 19 was the key step in the total synthesis of (+)-obolactone reported (Org. Lett. 2013, 15, 1294) by Reinhard Brückner at the University of Freiburg in Germany. Kiyotomi Kaneda at the University of Osaka found (Angew. Chem. Int. Ed. 2013, 52, 5961) that a palladium salt catalyzes the conversion of electron-deficient internal olefin 20 to ketone 21. As part of a program to develop environmentally sustainable procedures, Caterina Fusco at the University of Bari in Italy described (Tetrahedron Lett. 2013, 54, 515) the oxidative cleavage of lactam 22 by methyl(trifluoromethyl)dioxirane in water to produce ω-nitro acid 24. Motomu Kanai at the University of Tokyo reported (Org. Lett. 2013, 15, 1918) the β-functionalization of tertiary aromatic amine 25 with nitroolefin 26 to produce 27 by iron catalysis.

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Taber, Douglass F. "Advances in Organic Functional Group Transformation." In Organic Synthesis. Oxford University Press, 2013. http://dx.doi.org/10.1093/oso/9780199965724.003.0006.

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There have been several significant advances in N-alkylation using alcohols. Matthias Beller of Universität Rostock devised (Angew. Chem. Int. Ed. 2010, 49, 8126) a Ru catalyst for the amination of secondary and benzylic primary alcohols with ammonia. Dieter Vogt of the Eindhoven University of Technology reported (Angew. Chem. Int. Ed. 2010, 49, 8130) related transformations. Pei-Qiang Huang of Xiamen University showed (Chem. Commun. 2010, 46, 7834) that debenzylation of 3 in methanol led to the N-methyl amine 4. Parallel results have been reported with Ir (J. Am. Chem. Soc. 2010, 132, 15108), Au (Chem. Eur. J. 2010, 16, 13965), and Cu (Chem. Lett. 2010, 39, 1182). Peter J. Scammells of Monash University found (J. Org. Chem. 2010, 75, 4806) that demethylation of an N-oxide could be effected with Fe powder. Yao Fu and Qingxiang Guo of the University of Science and Technology of China N-vinylated (Tet. Lett. 2010, 51, 5476) a sulfonamide 7 with vinyl acetate and a Pd catalyst. Acyl amides could also be N-vinylated under these conditions. Hirokazu Urabe of the Tokyo Institute of Technology reported (Org. Lett. 2010, 12, 4137) that the stereodefined secondary sulfonamide of 9 could be displaced by an internal nucleophile, to give the product 11 with inversion of absolute configuration. Teruo Umemoto of IM&T Research devised (J. Am. Chem. Soc. 2010, 132, 18199) the remarkable fluorinating agent 13. In addition to converting secondary alcohols to the corresponding fluorides and ketones to gem-difluorides, 13 cleanly converted the carboxylic acids of 12 to trifluoromethyl groups. Paul G. Williard of Brown University demonstrated (Org. Lett. 2010, 12, 5378) that LDA converted an allyl ether 15 specifically to the (Z)-propenyl ether 16. Phil Lee Ho of Kangwon National University and Sunggak Kim of Nanyang Technological University could add (Angew. Chem. Int. Ed. 2010, 49, 6806) a phosphate to an alkyne 17 to make either the less substituted or the more substituted enol phosphate. Professor Kim reported (J. Org. Chem. 2010, 75, 7928) similar results with the addition of carboxylic acids.

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Taber, Douglass F. "C–H Functionalization." In Organic Synthesis. Oxford University Press, 2015. http://dx.doi.org/10.1093/oso/9780190200794.003.0019.

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Masayuki Inoue of the University of Tokyo oxidized (Tetrahedron Lett. 2011, 52, 4654) the alkyl benzene 1 to the nitrate 2, which could be carried on to the amide 5, the nitrile 6, the alcohol 7, or the azide 8. X. Peter Zhang of the University of South Florida developed (Chem. Sci. 2012, 2, 2361) a Co catalyst for the cyclization of 7 to 8. Justin Du Bois of Stanford University reported (J. Am. Chem. Soc. 2011, 133, 17207) the oxidative cyclization of the sulfamate corresponding to 7 using a Ru catalyst. Seongmin Lee of the University of Texas showed (Org. Lett. 2011, 13, 4766) that the oxidative cyclization of 9 gave the amine 10 with high diastereoselectivity. Fabrizio Fabris of the Università di Venezia used (Tetrahedron Lett. 2011, 52, 4478) a Ru catalyst to oxidize 11 to the ketone 12. Ying-Yeung Yeung of the National University of Singapore found (Org. Lett. 2011, 13, 4308) that hypervalent iodine was sufficient to oxidize 13 to the ketone 14. Huanfeng Jiang of the South China University of Technology methoxycarbonylated (Chem. Commun. 2011, 47, 12224) 15 under Pd catalysis to give 16. Professor Inoue found (Org. Lett. 2011, 13, 5928) that the oxidative cyanation of 17 proceeded with high diastereoselectivity to give 18. Mamoru Tobisu and Naoto Chatani of Osaka University activated (J. Am. Chem. Soc. 2011, 133, 12984) 19 with a Pd catalyst to enable coupling with 20 to give 21. Rh-mediated intramolecular insertion is well known to proceed efficiently into secondary and tertiary C–H bonds. A. Srikrishna of the Indian Institute of Science, Bangalore found (Synlett 2011, 2343) that insertion into the methyl C–H of 22 also worked smoothly to deliver 23. The macrocyclic oligopeptide valinomycin 24 has nine isopropyl groups. It is remarkable, as observed (Org. Lett. 2011, 13, 5096) by Cosimo Annese of the Università di Bari and Paul G. Williard of Brown University, that direct oxidation of 24 with methyl(trifluoromethyl) dioxirane in acetone specifically hydroxylated at 8 (45.5%, our numbering), 7 (28.5%), and 6 (26%).

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Taber, Douglass F. "The Snyder Synthesis of Psylloborine A." In Organic Synthesis. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780190646165.003.0099.

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In addition to the monomeric coccinellid alkaloids produced by the ladybug, some dimeric alkaloids, exemplified by psylloborine A 3, have been isolated. Scott A. Snyder of Scripps/Florida initially attempted a direct dimerization strategy for the assembly of 3, but when that failed, he devised (J. Am. Chem. Soc. 2014, 136, 9743) a route to the tethered dimer 1, that could indeed be cyclized to 2, the immediate precursor to 3. The starting material for both 9, the lower half of 1, and 13, the upper half of 1, was the commercial, enantiomerically-pure piperidine 4. Metalation followed by allylation gave the desired trans diastereomer 5. Oxidative cleavage followed by condensation with 6 gave the ester 7, that was hydrogenated, then converted with 8 to the desired phosphonate 9. To prepare 13, 4 was metalated and alkylated with methallyl bromide. The product 10 was carried on to the enone 12 by oxidative cleavage followed by the addition of 11, oxidative cleavage, and dehydration. Reduction to the desired diastereomer was achieved by conjugate addition of hydride in the presence of the sterically very demanding Yamamoto Lewis acid ATPH. Deprotection followed by oxidation then gave 13, that was condensed with 9 and deprotected to give 14. Selective deprotection followed by oxidation and condensation with 15 then led to 1. A key element in the design of this synthesis was the ability to easily tune the sulfone activating group, to direct the proper order of bond formation. The vision was that regeneration of the enone and deprotection, with tetramethylguanidine, would lead to 16. The free amine would add to the saturated ketone to give an enamine, that would in turn add in a conjugate sense to the enone to give 17. Further deprotection of 17 under acid conditions would again generate an enamine that, it was hoped, would, after further cyclization, add to the unsaturated sulfone to give 2. As illustrated, the 3,5-bis(trifluoromethyl)phenyl sulfone gave the best results. Desulfurization of 2 completed the synthesis of the complex dimeric alkaloid psylloborine A 3.

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