- Synthesis and reductive elimination of arylPd(II) trifluoromethyl complexes: A remarkable concentration effect on chemoselectivity
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Reductive elimination from Pd(II) aryl trifluoromethyl complexes is a challenging and elusive step which is accompanied by a number of kinetically more favorable side reactions giving rising to a complex mixture. We report herein the synthesis and isolation of several arylPd(II) trifluoromethyl complexes (2a-c) and study their electronic structures, photophysical properties and reductive elimination reactivities. A remarkable concentration effect on chemoselectivity is observed for thermal decomposition of (Xantphos)Pd(II)(Ar)(CF3) (2c) that favors the formation of Ar-CF3 at lower concentrations, but gives increasingly more Ar-Ar homocoupling product to a dominant extent as the concentration of 2c increases. This is solid evidence for the involvement of an intermolecular Ar/CF3 ligand exchange/Ar-Ar reductive elimination mechanism that has been proposed based on DFT computational studies. The interplay between theory and experiment provides valuable insights into the mechanism and kinetics of the key elementary reaction of reductive elimination at Pd(II), and may thus prompt the design of more efficient Pd-mediated nucleophilic trifluoromethylation reactions.
- Zhang, Song-Lin,Deng, Zhu-Qin
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- Cross-Coupling through Ag(I)/Ag(III) Redox Manifold
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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.
- Demonti, Luca,Mézailles, Nicolas,Nebra, Noel,Saffon-Merceron, Nathalie
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supporting information
p. 15396 - 15405
(2021/10/12)
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- Au@ZnO Core-Shell: Scalable Photocatalytic Trifluoromethylation Using CF3CO2Na as an Inexpensive Reagent under Visible Light Irradiation
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Trifluoromethylation is of significant importance for the synthesis of many small molecules vital for medicinal and agrochemical research. The importance of the CF3 group as well as the related synthetic challenges is so evident that many reagents have been reported for the synthesis of trifluoromethylated compounds, but these typical reagents are expensive and the methods for preparing them are difficult. Here, we report a new scalable and operationally simple trifluoromethylation reaction using sodium trifluoroacetate as a reagent and Au-modified ZnO as a photocatalyst under visible light irradiation. The reaction proceeds via trifluoromethylation of a broad range of aryl halides, arylboronic acids, and arene and heteroarene substrates. Some pharmaceutical and agrochemical compounds have been trifluoromethylated directly to demonstrate the applicability of the method.
- Bazyar, Zahra,Hosseini-Sarvari, Mona
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supporting information
p. 2345 - 2353
(2019/10/16)
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- Isolation of OH-bridged Ag(i)/Cu(iii) and ion-pair Cu(i)/Cu(iii) trifluoromethyl complexes with monophosphines
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Cu(iii)-CF3 complexes are important intermediates of both synthetic and mechanistic interest. This study describes the isolation, and spectroscopic and X-ray crystallographic characterization of CuIII-CF3 complexes 2-4 with typical monophosphine ligands PPh3 and Buchwald-type biarylmonophosphines. Distinct from the ion-pair [P2Cu(i)]+[Cu(iii)(CF3)4]? structures of 2 and 4 (P: PPh3 or SPhos), complex 3 exhibits a novel OH-bridged Ag(i)-Cu(iii) dinuclear structure with XPhos-coordinated linear Ag(i) and square planar Cu(iii) components. This is the first heterobimetallic Cu(iii)-CF3 complex confirmed by both solution-phase NMR spectroscopy and solid state X-ray crystal structure analysis. Complex 3 is found to have the LUMO orbital of major σ*(Cu-CF3) nature and electrophilic CF3 ligands. Accordingly, complex 3 is able to trifluoromethylate 2 equivalents of aryl boronic acids in up to quantitative yields, regardless of the inert or oxidative conditions. In contrast, the ion-pair complexes 2 and 4 show low reactivity. This study enriches the coordination and reactivity chemistry of Cu(iii)-CF3 compounds and shows the feasibility of modulation of structures and reactivity by ligand design, which may inspire future efforts on Cu(iii)-CF3 chemistry.
- Xiao, Chang,Zhang, Song-Lin
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supporting information
p. 848 - 853
(2019/01/21)
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- Air-Sensitive Photoredox Catalysis Performed under Aerobic Conditions in Gel Networks
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In this work, we demonstrate that useful C-C bond-forming photoredox catalysis can be performed in air using easily prepared gel networks as reaction media to give similar results as are obtained under inert atmosphere conditions. These reactions are completely inhibited in homogeneous solution in air. However, the supramolecular fibrillar gel networks confine the reactants and block oxygen diffusion, allowing air-sensitive catalytic activity under ambient conditions. We investigate the mechanism of this remarkable protection, focusing on the boundary effect in the self-assembled supramolecular gels that enhances the rates of productive reactions over diffusion-controlled quenching of excited states. Our observations suggest the occurrence of triplet-sensitized chemical reactions in the gel networks within the compartmentalized solvent pools held between the nanofibers. The combination of enhanced viscosity and added interfaces in supramolecular gel media seems to be a key factor in facilitating the reactions under aerobic conditions.
- H?ring, Marleen,Abramov, Alex,Okumura, Keisuke,Ghosh, Indrajit,K?nig, Burkhard,Yanai, Nobuhiro,Kimizuka, Nobuo,Díaz Díaz, David
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p. 7928 - 7938
(2018/06/04)
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- Diverse copper(iii) trifluoromethyl complexes with mono-, bi- and tridentate ligands and their versatile reactivity
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Cu(iii) trifluoromethyl complexes are proposed as essential intermediates for many copper-promoted trifluoromethylation reactions, but remain elusive and scarcely explored. We report herein the isolation and spectroscopic and X-ray crystallographic charac
- Zhang, Song-Lin,Xiao, Chang,Wan, Hai-Xing
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supporting information
p. 4779 - 4784
(2018/04/11)
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- Visible-Light photoredox decarboxylation of perfluoroarene iodine(III) Trifluoroacetates for C-H trifluoromethylation of (Hetero)arenes
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A scalable and operationally simple decarboxylative trifluoromethylation of (hetero)arenes with easily accessible C6F5I(OCOCF3)2 under photoredox catalysis has been developed. This method is tolerant of various (hetero)arenes and functional groups. Notably, C6F5I is recycled from the decarboxylation reaction and further used for the preparation of C6F5I(OCOCF3)2. The combination of photoredox catalysis and hypervalent iodine reagent provides a practical approach for the application of trifluoroacetic acid in trifluoromethylation reactions.
- Yang, Bin,Yu, Donghai,Xu, Xiu-Hua,Qing, Feng-Ling
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p. 2839 - 2843
(2018/04/14)
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- Copper-Promoted Conversion of Aromatic Amines into Trifluoromethylated Arenes: One-Pot Sandmeyer Trifluoromethylation
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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.
- Hong, Jianquan,Wang, Guifu,Huo, Lianguang,Zheng, Changge
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supporting information
p. 1761 - 1767
(2017/09/06)
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- Pd-Catalyzed Decarbonylative Cross-Couplings of Aroyl Chlorides
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This report describes a method for Pd-catalyzed decarbonylative cross-coupling that enables the conversion of carboxylic acid derivatives to biaryls, aryl amines, aryl ethers, aryl sulfides, aryl boronate esters, and trifluoromethylated arenes. The success of this transformation leverages the Pd0/Brettphos-catalyzed decarbonylative chlorination of aroyl chlorides, which can then participate in diverse cross-coupling reactions in situ using the same Pd catalyst.
- Malapit, Christian A.,Ichiishi, Naoko,Sanford, Melanie S.
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p. 4142 - 4145
(2017/08/15)
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- Synthesis of trifluoromethyl moieties by late-stage copper (I) mediated nucleophilic fluorination
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The nucleophilic fluorination of bromodifluoromethyl derivatives mediated by the complex (PPh3)3CuF is described. Under the reaction conditions, different trifluoroacetates, trifluoroketones, trifluoroarenes and trifluoroacetamides were obtained in good yields.
- Bermejo Góme, Antonio,González, Miguel A. Cortés,Lübcke, Marvin,Johansson, Magnus J.,Schou, Magnus,Szabó, Kálmán J.
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- Copper-mediated trifluoromethylation of diaryliodonium salts with difluoromethyltriflate
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The reaction of diaryliodonium salts with difluoromethyltriflate in the presence of TBAT and CuTC gave the corresponding trifluoromethylated arenes in moderate yields. Compared to other difluorocarbene-derived trifluoromethylation reactions, the current one proceeded at mild reaction conditions (room temperature) within short reaction time (5 min).
- Yang, Jing-Yun,Xu, Xiu-Hua,Qing, Feng-Ling
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- Trifluoromethylation of (hetero)aryl iodides and bromides with copper(i) chlorodifluoroacetate complexes
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A new copper-mediated trifluoromethylation reaction using copper(i) chlorodifluoroacetate complexes as reagents is reported. The complex [L2Cu][O2CCF2Cl] (L = bpy, dmbpy, phen) reacted with (hetero)aryl iodides and bromides in the presence of CsF in DMF at 75 °C to afford the trifluoromethylarenes in good to excellent yields. High compatibility with various chemical functions or (hetero)cycles was also observed in the reaction. A reaction mechanism involving a difluorocarbene intermediate, along with a subsequent formation of a -CF3 anion was proposed.
- Lin, Xiaoxi,Li, Zhengyu,Han, Xiaoyan,Weng, Zhiqiang
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p. 75465 - 75469
(2016/08/24)
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- Copper-catalysed synthesis of trifluoromethyl(hetero)arenes from di(hetero)aryl-λ3-iodanes
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An efficient synthesis of trifluoromethylated (hetero)arenes has been achieved through the regioselective copper-catalyzed trifluoromethylation of di(hetero)aryl-λ3-iodanes, employing readily available trifluoromethyltrimethylsilane. The reaction works well for both symmetrical and unsymmetrical di(hetero)aryl-λ3-iodanes with good regioselectivity and also tolerates diverse functional groups such as bromo, iodo, cyano, nitro, ester, ketone and enolizable ketone.
- Pandey, Vinay Kumar,Anbarasan, Pazhamalai
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p. 18525 - 18529
(2016/02/27)
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- Study on the degradation of the highly reactive hypervalent trifluoromethylation iodine reagent PhI(OAc)(CF3)
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Degradation of the highly reactive hypervalent trifluoromethylation iodine reagent PhI(OAc)(CF3), which can only be generated in situ with mixing PhI(OAc)2 and TMSCF3 in the presence of CsF, was studied by ESI-MS and GC-MS combined with 19F-NMR. The important transient intermediate PhICF3+ was determined by ESI-MS, and the major volatile products containing CF3 were identified with the authentic compounds by using GC-MS, such as trifluoromethylbenzene, 2-iodobenzotrifluoride, 3-iodobenzotrifluoride, 4-iodobenzotrifluoride. Meanwhile, more evidences obtained with 19F-NMR were given for such degradation reaction. A possible rapid CF3 radical transfer reaction pathway was proposed to clarify such degradation progress based on the experimental results. Therefore, this study may be helpful in elucidating the intrinsic reactivity of PhI(OAc)(CF3) and the possible competing side reactions caused by such self-degradation pathway. Degradation of the highly reactive hypervalent trifluoromethylation iodine reagent PhI(OAc)(CF3), which can only be generated in situ with mixing PhI(OAc)2 and TMSCF3 in the presence of CsF, was studied by ESI-MS and GC-MS combined with 19F-NMR. The important transient intermediate PhICF3+ was determined by ESI-MS, and the major volatile products containing CF3 were identified with the authentic compounds by using GC-MS, such as trifluoromethylbenzene, 2-iodobenzotrifluoride, 3-iodobenzotrifluoride, 4-iodobenzotrifluoride. Meanwhile, more evidences obtained with 19F-NMR were given for such degradation reaction. A possible rapid CF3 radical transfer reaction pathway was proposed to clarify such degradation progress based on the experimental results. Therefore, this study may be helpful in elucidating the intrinsic reactivity of PhI(OAc)(CF3) and the possible competing side reactions caused by such self-degradation pathway.
- Zhu, Hui,Zhang, Shusheng,Wang, Haoyang,Xu, Bin,Guo, Yinlong
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supporting information
p. 1365 - 1370
(2016/02/18)
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- Copper-mediated trifluoromethylation of diaryliodonium salts with TMSCF3 at room temperature
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A convenient method for the preparation of trifluoromethylated arenes from the reaction of diaryliodonium salts with TMSCF3 in the presence of CuBF4·(MeCN)4 and KF at room temperature within 25 min was developed. This reaction provides a valuable complement to the previously established trifluoromethylation methods.
- Yang, Jing-Yun,Xu, Xiu-Hua,Qing, Feng-Ling
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p. 175 - 180
(2015/10/20)
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- Direct synthesis of a trifluoromethyl copper reagent from trifluoromethyl ketones: Application to trifluoromethylation
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Being economic with fluorine: The direct synthesis of CuCF3 from a cuprate reagent and trifluoromethyl ketones, as one of the most economical and efficient trifluoromethyl sources, was accomplished. The advantages of this method are all of reagents employed are low-cost, operation is simple, and the yield of CuCF3 is virtually quantitative (see scheme). Furthermore, three types of trifluoromethylations smoothly proceeded to provide the corresponding products in high yields. Copyright
- Serizawa, Hiroki,Aikawa, Kohsuke,Mikami, Koichi
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supporting information
p. 17692 - 17697
(2014/01/17)
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- Copper-catalysed process for the production of substituted or unsubstituted trifluormethylated aryl and heteroaryl compounds
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The present invention relates to a process for the production of triffluoromethylated unsubstituted or substituted aryl or heteroaryl compounds which comprises reacting an unsubstituted or substituted aryl or heteroaryl halide with a trifluoroacetate of formula (I) or (II), wherein R1 is hydrogen or a C1-C5 alkyl group and M an alkali metal or an ammonium ion, in the presence of a copper salt as catalyst and an anorganic halogenide salt or a trifluoroacetacid salt as activator compound.
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Page/Page column 5; 9
(2012/05/20)
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- FLUOROALKYLATION METHODS AND REAGENTS
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A method of forming a fluorinated molecular entity includes reacting in a reaction mixture an aromatic halide, copper, a fluoroalkyl group, and a ligand. The aromatic halide includes an aromatic group and a halogen substituent bonded to the aromatic group. The ligand includes at least one group-V donor selected from phosphorus and an amine. The overall molar ratio of copper to aromatic halide in the reaction mixture is from 0.2 to 3. The method further includes forming a fluoroalkylarene including the aromatic group and the fluoroalkyl group bonded to the aromatic group. A composition, which may be used in the method, consists essentially of copper, the fluoroalkyl group, and the ligand, where the molar ratio of copper to the fluoroalkyl group is approximately 1.
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Page/Page column 7; 41
(2012/03/11)
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- Practical method for the Cu-mediated trifluoromethylation of arylboronic acids with CF3 radicals derived from NaSO2CF3 and tert-butyl hydroperoxide (TBHP)
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A mild and practical protocol for the copper-mediated trifluoromethylation of aryl and heteroaryl boronic acids using NaSO2CF3 (Langlois' reagent) and TBHP is described. The reaction proceeds at room temperature under ambient conditions, and the products can be readily purified by extraction or column chromatography.
- Ye, Yingda,Kuenzi, Stefan A.,Sanford, Melanie S.
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supporting information
p. 4979 - 4981,3
(2012/12/12)
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- Practical method for the Cu-mediated trifluoromethylation of arylboronic acids with CF3 radicals derived from NaSO2CF3 and tert-butyl hydroperoxide (TBHP)
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A mild and practical protocol for the copper-mediated trifluoromethylation of aryl and heteroaryl boronic acids using NaSO2CF3 (Langlois' reagent) and TBHP is described. The reaction proceeds at room temperature under ambient conditions, and the products can be readily purified by extraction or column chromatography.
- Ye, Yingda,Künzi, Stefan A.,Sanford, Melanie S.
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supporting information
p. 4979 - 4981
(2013/01/15)
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- Fluoroform-derived CuCF3 for low-cost, simple, efficient, and safe trifluoromethylation of aryl boronic acids in air
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Easy does it: Aryl boronic acids undergo smooth and selective trifluoromethylation with low-cost fluoroform-derived CuCF3 in DMF in non-dried air. The reaction occurs under mild conditions (1 atm, room temperature), exhibits unprecedented funct
- Novak, Petr,Lishchynskyi, Anton,Grushin, Vladimir V.
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supporting information; experimental part
p. 7767 - 7770
(2012/08/29)
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- Merging visible-light photocatalysis and transition-metal catalysis in the copper-catalyzed trifluoromethylation of boronic acids with CF3I
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This communication describes the development of a mild method for the cross-coupling of arylboronic acids with CF3I via the merger of photoredox and Cu catalysis. This method has been applied to the trifluoromethylation of electronically diverse aromatic and heteroaromatic substrates and tolerates many common functional groups.
- Ye, Yingda,Sanford, Melanie S.
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supporting information; experimental part
p. 9034 - 9037
(2012/07/13)
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- Palladium-catalyzed borylation of sterically demanding aryl halides with a silica-supported compact phosphane ligand
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Immobile but active: A silica-supported "compact" phosphane, Silica-SMAP, can be used in the Pd-catalyzed borylation of aryl chlorides or bromides with bis(pinacolato)diboron (see scheme). The Silica-SMAP/Pd system significantly expands the substrate scope of the borylation toward sterically and electronically challenging aryl halides.
- Kawamorita, Soichiro,Ohmiya, Hirohisa,Iwai, Tomohiro,Sawamura, Masaya
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supporting information; experimental part
p. 8363 - 8366
(2011/10/09)
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- Simple, stable, and easily accessible well-defined CuCF3 aromatic trifluoromethylating agents
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Give me an F: Exceptionally easy to make in over 90 yield (see scheme) and air-stable in the solid state, [(Ph3P)3Cu(CF3)] is a remarkable example of a rarely encountered well-defined Cu(I) trifluoromethylating agent and a convenient starting material for the synthesis of other CuCF3 complexes, such as [(phen)Cu(PPh3)(CF 3)]. Copyright
- Tomashenko, Olesya A.,Escudero-Adan, Eduardo C.,Martinez Belmonte, Marta,Grushin, Vladimir V.
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supporting information; experimental part
p. 7655 - 7659
(2011/10/02)
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- Cooperative effect of silver in copper-catalyzed trifluoromethylation of aryl iodides using Me3SiCF3
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An effective model of cooperative effect of silver for the coppercatalyzed trifluoromethylation of activated and unactivated aryl iodides to trifluoromethylated arenes using Me3SiCF3 was achieved with a broad substrate scope.
- Weng, Zhiqiang,Lee, Richmond,Jia, Weiguo,Yuan, Yaofeng,Wang, Wenfeng,Feng, Xue,Huang, Kuo-Wei
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experimental part
p. 3229 - 3232
(2011/07/31)
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- Mechanistic and computational studies of oxidatively-induced Aryl-CF 3 bond-formation at Pd: Rational design of room temperature aryl trifluoromethylation
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This article describes the rational design of first generation systems for oxidatively induced Aryl-CF3 bond-forming reductive elimination from PdII. Treatment of (dtbpy)PdII(Aryl)(CF3) (dtbpy = di-tert-butylbipyridine) with NFTPT (N-fluoro-1,3,5-trimethylpyridinium triflate) afforded the isolable PdIV intermediate (dtbpy)Pd IV(Aryl)(CF3)(F)(OTf). Thermolysis of this complex at 80 °C resulted in Aryl-CF3 bond-formation. Detailed experimental and computational mechanistic studies have been conducted to gain insights into the key reductive elimination step. Reductive elimination from this PdIV species proceeds via pre-equilibrium dissociation of TfO- followed by Aryl-CF3 coupling. DFT calculations reveal that the transition state for Aryl-CF3 bond formation involves the CF3 acting as an electrophile with the Aryl ligand serving as a nucleophilic coupling partner. These mechanistic considerations along with DFT calculations have facilitated the design of a second generation system utilizing the tmeda (N,N,N′,N′-tetramethylethylenediamine) ligand in place of dtbpy. The tmeda complexes undergo oxidative trifluoromethylation at room temperature.
- Ball, Nicholas D.,Gary, J. Brannon,Ye, Yingda,Sanford, Melanie S.
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supporting information; experimental part
p. 7577 - 7584
(2011/06/25)
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- From carboxylic acids to the trifluoromethyl group using BrF3
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Organic trifluoromethyl derivatives were made from aromatic and aliphatic carboxylic acids by transforming them first into the corresponding dithioesters followed by reaction with bromine trifluoride under mild conditions (0 °C, 2 min).
- Cohen, Or,Mishani, Eyal,Rozen, Shlomo
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experimental part
p. 3579 - 3582
(2010/07/04)
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- Efficient synthesis of p-bis-(chlorodifluoromethyl)benzene
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Selective, high yield partial fluorination of p-bis-(trichloromethyl)benzene to p-bis-(chlorodifluoromethyl)benzene has been accomplished by warming a slurry of the p-bis-(trichloromethyl)benzene in anhydrous HF which also contains a small quantity of inert solvent, such as 1,2-dichloroethane.
- Dolbier Jr., William R.,Duan, Jian-Xin,Rong, Xiao X.
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p. 1091 - 1093
(2008/02/08)
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- A Novel Method for Converting Aromatic Acids into Trifluoromethyl Derivatives using BrF3
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Aryltrifluoromethyl derivatives are obtained in good yields from the corresponding aryl carboxylic acids by reacting their dithionic esters with BrF3 under very mild conditions.
- Rozen, Shlomo,Mishani, Eyal
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p. 2081 - 2082
(2007/10/02)
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- Methyl 3-Oxa-ω-fluorosulfonylperfluoropentanoate: a Versatile Trifluoromethylating Agent for Organic Halides
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Methyl 3-oxa-ω-fluorosulfonylperfluoropentanoate FSO2CF2CF2OCF2CO2Me 1, prepared through the reaction of readily available ICF2CF2OCF2CF2SO2F and SO3 followed by MeOH, is a very convenient trifluoromethylating agent; in the presence of copper(I) iodide, 1 not only reacts with vinyl, benzyl allyl, phenyl iodides and bromides, but also with aryl chlorides to give the corresponding trifluoromethyl compounds in moderate to high yield; a probable reaction mechanism is proposed.
- Chen, Qing-Yun,Duan, Jian-Xing
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p. 1389 - 1391
(2007/10/02)
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- TRIFLUORMETHYLIERUNGSREAKTIONEN VON Te(CF3)2 MIT HALOGENBENZOLEN UND METHYLBENZOLEN
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Substituent effects on yields and regioselectivity of photochemical and thermal trifluoromethylation reactions of Te(CF3)2 with halogen benzenes and methyl benzenes are investigated under comparable conditions.All reactions lead to trifluoromethylated products.The yields of the thermal are always higher than those of the corresponding photochemical reactions.The reactivity of the halobenzenes increases in the series C6H5-F a sidereaction, but H-substitution is the primary reaction pathway.During the reactions with iodobenzene tellurium containing compounds are also formed.The reactions with methyl benzenes show an increase in reactivity in the series hexamethylbenzene mesitylene toluene p-xylene.In all cases only ring substituted products are detected.Reactions with toluene and p-xylene yield tellurium containing compounds as well as addition products.The 19F-n.m.r spectra of the products are given.
- Naumann, Dieter,Kischkewitz, Jurgen
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p. 283 - 299
(2007/10/02)
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- Sodium Perfluoroalkane Carboxylates as Sources of Perfluoroalkyl Groups
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Sodium trifluoroacetate, in the presence of copper(I) iodide, is used as a source of trifluoromethyl to replace halogen by trifluoromethyl in benzenoid and heterocyclic aromatic systems, as well as in alkenyl and alkyl halogen compounds.The mechanism of this interesting copper-assisted process has been explored and an intermediate of the form - is proposed.Introduction of higher perfluoroalkyl groups from their respective sodium perfluoroalkane carboxylates has been demonstrated and the machanistic features are compared with those of the trifluoromethylation process.
- Carr, Gillian E.,Chambers, Richard D.,Holmes, Thomas F.,Parker, David G.
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p. 921 - 926
(2007/10/02)
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