- A convenient synthesis of Trifluoroacetamides from sodium trifluoroacetate and amines
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Trifluoroacetamides were prepared readily by reaction of sodium trifluoroacetate with triphenylphosphine di-iodide and amines consecutively under mild conditions with good yields.
- Zhou, Qi-Zhong,Chen, Zhen-Chu
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- Z-Selective Fluoroalkenylation of (Hetero)Aromatic Systems by Iodonium Reagents in Palladium-Catalyzed Directed C?H Activation
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The direct and catalytic incorporation of fluorine containing molecular motifs into organic compounds resulting high-value added chemicals represents a rapidly evolving part of synthetic methodologies, thus this area is in the focus of pharmaceutical and agrochemical research. Herein we report a stereoselective procedure for direct fluorovinylation of aromatic and heteroaromatic scaffolds. This methodology development has been realized by palladium-catalyzed ortho C?H activation reaction of aniline derivatives featuring the regioselectivity via directing groups such as secondary of tertiary amides, ureas or ketones. The application of non-symmetrical aryl(fluoroalkenyl)-iodonium salts as fluoroalkenylating agents allowed mild reaction conditions in general for this transformation. The scope and limitations have been thoroughly investigated and the feasibility has been demonstrated by more than 50 examples.
- Tóth, Balázs L.,Sályi, Gerg?,Domján, Attila,Egyed, Orsolya,Bényei, Attila,Gonda, Zsombor,Novák, Zoltán
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supporting information
p. 348 - 354
(2021/11/09)
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- A simple and efficient method for trifluoroacetylation of arylamines using trifluoroacetic acid and triphosgene
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A simple and efficient one-pot procedure for trifluoroacetylation of arylamines using trifluoroacetic acid and triphosgene is reported. A mixed trifluoroacetic anhydride generated in situ reacts with a variety of arylamines to give the corresponding trifluroacetamides in high yields.
- Han, Ki-Jong,Kim, Misoo
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experimental part
p. 559 - 561
(2012/06/04)
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- A one-pot procedure for trifluoroacetylation of arylamines using trifluoroacetic acid as a trifluoroacetylating reagent
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A convenient procedure for the preparation of aryl trifluoroacetamides from aryl amines is described that employs 2-4 M equiv of trifluoroacetic acid in refluxing xylene as a trifluoroacetylating agent. Addition of an amount of pyridine that is equimolar to the amount of trifluoroacetic acid present in the reaction mixture facilitates the trifluoroacetylation of rather basic arylamines.
- Ohtaka, Junpei,Sakamoto, Takeshi,Kikugawa, Yasuo
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experimental part
p. 1681 - 1683
(2009/09/05)
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- Synthesis, structure, and reactions of (acylimino)triaryl-λ5-bismuthanes: First comparative study of the (acylimino)pnictorane series
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The synthesis, structure, and reactions of (acylimino)triaryl-λ5-bismuthanes and a comparative study of the structure and reactivity of a series of (acylimino)pnictoranes are reported. Treatment of ortho-substituted triarylbismuth dichlorides 1 (Ar3BiCl2; Ar = 2-MeC6H4, 2-MeOC6H4, 2,4,6-Me3C6H2) with amides 2 (H2-NCOR; R = CF3, CCl3, 3,5-(CF3)2C6H3) in the presence of 2.2 equiv of KO-t-Bu in dichloromethane afforded (acylimino)triaryl-λ5-bismuthanes 3 (Ar3Bi=NCOR) in yields of 77-96%. The ortho-substituted aryl ligands and the electron-withdrawing N-substituents afford kinetic and thermodynamic stabilization, respectively, to the reactive Bi=N bond. The structures and properties of a series of (acylimino)pnictoranes (Ar3M=NCOR and H3M=NCOCF3; M = P, As, Sb, Bi) are compared by IR and 13C and 15N NMR, X-ray crystallography, and ab initio molecular orbital calculations. It was found that the contribution of the M+-N=C-O- canonical form becomes more prominent and the single-bond character of the M=N bond increases progressively as the pnictogen atom becomes heavier. The Bi=N bond of (acylimino)-λ5-bismuthanes 3 possesses a highly polarized single-bond character, probably due to the differences in orbital size and electronegativity between the bismuth and nitrogen atoms. Thermal decomposition of (aroylimino)triaryl-λ5-bismuthane 3f (o-Tol3Bi=NCOAr; Ar = 3,5-(CF3)2C6H3) produces a gel in dry conditions or aniline 12 (ArNH2) in slightly wet conditions with a good recovery of tris(2-methylphenyl)bismuthane (4a). It is likely that the aryl isocyanate 13 (ArNCO) is produced during the thermolysis via a concerted C → N migration of the Ar group with an elimination of the triarylbismuthonio group as bismuthane 4a. (Acylimino)triaryl-λ5-bismuthanes 3 oxidize 1,1,2,2-tetraphenylethanediol, benzenethiol, methanol, and ethanol to benzophenone, diphenyl disulfide, methyl formate, and acetaldehyde, respectively, in two different reaction pathways depending on the structure of the substrates. Compound 3d (o-Tol3Bi=NCOCCl3) transfers the nitrenoid moiety to triphenylphosphane, triphenylarsane, and tris(2-methylphenyl)stibane to give the corresponding (acylimino)pnictoranes (Ar3M=NCOCl3; M = P, As, Sb) and 4a, suggesting that 3d is thermodynamically much less stable than their lighter pnictogen counterparts. The copper-catalyzed decomposition of 3 (o-Tol3Bi=NCOR) afforded N-acyl-o-toluidines 18 (o-TolNHCOR) via a Bi → N migration of the tolyl group. The observed reactivities of (acylimino)triaryl-λ5-bismuthanes 3 demonstrate a good leaving ability of the bismuthonio group.
- Matano,Nomura,Suzuki,Shiro,Nakano
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p. 10954 - 10965
(2007/10/03)
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- A new, convenient and selective 4-dimethylaminopyridine-catalyzed trifluoroacetylation of anilines with ethyl trifluoroacetate
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A new, convenient, and selective 4-dimethylaminopyridine-catalyzed trifluoroacetylation of anilines with ethyl trifluoroacetate is described. Anilines, containing other functional groups, e.g. alcohols, phenols, hindered secondary amines, and secondary anilines, are also selectively trifluoroacetylated in high yields under these newly developed conditions. (C) 2000 Elsevier Science Ltd.
- Prashad,Hu,Har,Repic,Blacklock
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p. 9957 - 9961
(2007/10/03)
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- Microwave-promoted trifluoroacetylation of amines with TiO(CF3CO2)2
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Conversion of amines to their corresponding trifluoroacetamides was performed with TiO(CF3CO2)2 in a conventional microwave oven under solvent-free conditions in excellent yields.
- Iranpoor, Nasser,Zeynizadeh, Behzad
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p. 124 - 125
(2007/10/03)
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- First synthesis, structure, and reactivity of (acylimino)triaryl-λ5-bismuthanes stabilized by ortho-substituted aryl ligands
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The reactive Bi(V)=N bond in (acylimino)-triaryl-λ5-bismuthanes has been found to be stabilized effectively by ortho-substituted aryl ligands such as o-tolyl, o-anisyl, and mesityl groups. These imino-λ5-bismuthanes, in which the bismuth center possesses a distorted tetrahedral geometry, behave as a nitrene precursor as well as an oxidizing agent, depending on the substrates and conditions.
- Matano, Yoshihiro,Nomura, Hazumi,Shiro, Motoo,Suzuki, Hitomi
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p. 2580 - 2582
(2008/10/08)
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- Generation and Reaction of (N-Aryltrifluoroacetimidoyl)zinc Halide
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(N-Aryltrifluoroacetimidoyl)zinc halides were easily generated at room temparature by the oxidative addition of imidoyl halides to activated zinc powder. zinc halides react with aldehydes to give the corresponding alcohols smoothly to excellent yields.These adducts could be readily transformed to the α-amino ketones.
- Tamura, Kenji,Yan, Fengyang,Sakai, Takashi,Uneyama, Kenji
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p. 300 - 303
(2007/10/02)
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