454-90-0Relevant articles and documents
Cross-Coupling through Ag(I)/Ag(III) Redox Manifold
Demonti, Luca,Mézailles, Nicolas,Nebra, Noel,Saffon-Merceron, Nathalie
supporting information, p. 15396 - 15405 (2021/10/12)
In ample variety of transformations, the presence of silver as an additive or co-catalyst is believed to be innocuous for the efficiency of the operating metal catalyst. Even though Ag additives are required often as coupling partners, oxidants or halide scavengers, its role as a catalytically competent species is widely neglected in cross-coupling reactions. Most likely, this is due to the erroneously assumed incapacity of Ag to undergo 2e? redox steps. Definite proof is herein provided for the required elementary steps to accomplish the oxidative trifluoromethylation of arenes through AgI/AgIII redox catalysis (i. e. CEL coupling), namely: i) easy AgI/AgIII 2e? oxidation mediated by air; ii) bpy/phen ligation to AgIII; iii) boron-to-AgIII aryl transfer; and iv) ulterior reductive elimination of benzotrifluorides from an [aryl-AgIII-CF3] fragment. More precisely, an ultimate entry and full characterization of organosilver(III) compounds [K]+[AgIII(CF3)4]? (K-1), [(bpy)AgIII(CF3)3] (2) and [(phen)AgIII(CF3)3] (3), is described. The utility of 3 in cross-coupling has been showcased unambiguously, and a large variety of arylboron compounds was trifluoromethylated via [AgIII(aryl)(CF3)3]? intermediates. This work breaks with old stereotypes and misconceptions regarding the inability of Ag to undergo cross-coupling by itself.
Cathodic C-H Trifluoromethylation of Arenes and Heteroarenes Enabled by an in Situ-Generated Triflyltriethylammonium Complex
Cantillo, David,Jud, Wolfgang,Kappe, C. Oliver,Maljuric, Snjezana
supporting information, (2019/10/08)
While several trifluoromethylation reactions involving the electrochemical generation of CF3 radicals via anodic oxidation have been reported, the alternative cathodic, reductive radical generation has remained elusive. Herein, the first cathodic trifluoromethylation of arenes and heteroarenes is reported. The method is based on the electrochemical reduction of an unstable triflyltriethylammonium complex generated in situ from inexpensive triflyl chloride and triethylamine, which produces CF3 radicals that are trapped by the arenes on the cathode surface.
6-SHOGAOL DERIVATIVES AND ACTIVITIES THEREOF
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Paragraph 0180; 0184, (2018/10/19)
Derivatives of 6-shogaol are described herein. Also described herein are methods of preparing the derivatives, as well as methods of using the derivatives to activate Nrf2 and to treat diseases associated with inflammation and/or oxidative stress.
Preparation method of m-trifluoromethylphenol
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Paragraph 0065-0066; 0082; 0084; 0086, (2018/03/26)
The invention discloses a preparation method of m-trifluoromethylphenol. A preparation method of the m-trifluoromethylphenol comprises the following steps of enabling m-trifluoromethylphenol and alkali metal hydroxide and/or alkali metal alcohol to hydrolyze in an alcohol solvent under the condition of existence of a copper complex catalyst, and acidifying a reaction solution; the copper complex catalyst is selected from one or multiple of 8-copper hydroxyquinoline, 2-methyl-8-copper hydroxyquinoline, 4-methyl-8-copper hydroxyquinoline, copper acetate, and copper acetylacetonate. The preparation method has the advantages that the raw materials which can be easily purchased in industry are used for reacting, the technology is simple, the post-treatment is easy, the conditions are relativelymoderate, the pollution to environment is smaller, the m-trifluoromethylphenol with higher purity can be prepared at higher yield rate, the cost is low, and the industrialization application is realized. (The formula is shown in the description.).
Application of Silicon-Initiated Water Splitting for the Reduction of Organic Substrates
Gevorgyan, Ashot,Mkrtchyan, Satenik,Grigoryan, Tatevik,Iaroshenko, Viktor O.
, p. 375 - 382 (2018/06/04)
The use of water as a donor for hydrogen suitable for the reduction of several important classes of organic compounds is described. It is found that the reductive water splitting can be promoted by several metalloids among which silicon shows the best efficiency. The developed methodologies were applied for the reduction of nitro compounds, N-oxides, sulfoxides, alkenes, alkynes, hydrodehalogenation as well as for the gram-scale synthesis of several substrates of industrial importance.
Copper-Promoted Conversion of Aromatic Amines into Trifluoromethylated Arenes: One-Pot Sandmeyer Trifluoromethylation
Hong, Jianquan,Wang, Guifu,Huo, Lianguang,Zheng, Changge
supporting information, p. 1761 - 1767 (2017/09/06)
A simple copper-promoted one-pot Sandmeyer trifluoromethylation of aromatic amines with Langlois’ reagent has been demonstrated. The reaction is performed in mild reaction conditions under an air atmosphere with good substrate scope and functional group compatibility. It provides an alternative and straightforward synthetic approach to access a variety of trifluoromethylated arenes.
The first nucleophilic C-H perfluoroalkylation of aromatic compounds via (arene)tricarbonylchromium complexes
Kirij, Natalia V.,Filatov, Andrey A.,Khrapach, Gleb Yu.,Yagupolskii, Yurii L.
supporting information, p. 2146 - 2149 (2017/02/19)
The first nucleophilic perfluoroalkylation of arenes is based on the arene π-system activation via (η6-arene)tricarbonylchromium complexes. Perfluoroalkyl anions generated from Me3SiRF and a fluoride ion source [Me4N]F exclusively attack the arene ligand under mild conditions. The formed negatively charged analogs of Meisenheimer adducts readily undergo a one-pot oxidation to perfluoroalkyl arenes.
Phosphovanadomolybdic acid catalyzed direct C-H trifluoromethylation of (hetero)arenes using NaSO2CF3 as the CF3 source and O2 as the terminal oxidant
Li, Chifeng,Suzuki, Kosuke,Yamaguchi, Kazuya,Mizuno, Noritaka
supporting information, p. 1417 - 1420 (2017/02/23)
A direct C-H trifluoromethylation of (hetero)arenes using NaSO2CF3 (Langlois' reagent) as the CF3 source and O2 as the terminal oxidant has been developed. In the presence of catalytic amounts of phosphovanadomolybdic acids, such as H6PV3Mo9O40, various kinds of substituted benzenes and heteroaromatic compounds could be converted into the corresponding trifluoromethylated products.
Synthesis, evaluation, and metabolism of novel [6]-shogaol derivatives as potent Nrf2 activators
Zhu, Yingdong,Wang, Pei,Zhao, Yantao,Yang, Chun,Clark, Anderson,Leung, TinChung,Chen, Xiaoxin,Sang, Shengmin
, p. 243 - 254 (2016/04/20)
Oxidative stress is a central component of many chronic diseases. The Kelch-like ECH-associated protein 1 (Keap1)-nuclear factor erythroid 2 p45-related factor 2 (Nrf2) system is a major regulatory pathway of cytoprotective genes against oxidative and electrophilic stress. Activation of the Nrf2 pathway plays crucial roles in the chemopreventive effects of various inducers. In this study, we developed a novel class of potent Nrf2 activators derived from ginger compound, [6]-shogaol (6S), using the Tg[glutathione S-transferase pi 1 (gstp1):green fluorescent protein (GFP)] transgenic zebrafish model. Investigation of structure-activity relationships of 6S derivatives indicates that the combination of an α,β-unsaturated carbonyl entity and a catechol moiety in one compound enhances the Tg(gstp1:GFP) fluorescence signal in zebrafish embryos. Chemical reaction and in vivo metabolism studies of the four most potent 6S derivatives showed that both α,β-unsaturated carbonyl entity and catechol moiety act as major active groups for conjugation with the sulfhydryl groups of the cysteine residues. In addition, we further demonstrated that 6S derivatives increased the expression of Nrf2 downstream target, heme oxygenase-1, in both a dose- and time-dependent manner. These results suggest that α,β-unsaturated carbonyl entity and catechol moiety of 6S derivatives may react with the cysteine residues of Keap1, disrupting the Keap1-Nrf2 complex, thereby liberating and activating Nrf2. Our findings of natural product-derived Nrf2 activators lead to design options of potent Nrf2 activators for further optimization.
Isolation and characterization of copper(III) trifluoromethyl complexes and reactivity studies of aerobic trifluoromethylation of arylboronic acids
Zhang, Song-Lin,Bie, Wen-Feng
, p. 70902 - 70906 (2016/08/05)
The isolation, characterization and reactivity of transition metal trifluoromethyl complexes are fundamental and challenging topics in trifluoromethylation chemistry. We report herein the synthesis and isolation of two new complexes [(phen)CuI(PPh3)2]+[CuIII(CF3)4]- (2) and (phen)CuIII(CF3)3 (3) as well as a known complex (bpy)CuIII(CF3)3 (4) at room temperature. 2 and 3 have been fully characterized using 1H, 19F, 31P NMR, elemental analyses and X-ray crystallography. Reactivity studies indicate that 2 is unreactive toward arylboronic acids. In contrast, 3 and 4 can react with various aryl and heteroaryl boronic acids to deliver trifluoromethylated arenes in good to quantitative yields under mild conditions. The presence of a fluoride additive in DMF under aerobic conditions is crucial to these reactions. This study provides fundamental information about the structure and reactivity of elusive Cu(iii) trifluoromethyl complexes that have been proposed as relevant reactive intermediates in many trifluoromethylation reactions.
