13677-42-4Relevant academic research and scientific papers
Visible-Light- And PPh3-Mediated Direct C-N Coupling of Nitroarenes and Boronic Acids at Ambient Temperature
Manna, Kartic,Ganguly, Tanusree,Baitalik, Sujoy,Jana, Ranjan
supporting information, p. 8634 - 8639 (2021/11/01)
We present here a metal-free, visible-light- and triphenylphosphine-mediated intermolecular, reductive amination between nitroarenes and boronic acids at ambient temperature without any photocatalyst. Mechanistically, a slow reduction of nitroarenes to a nitroso and, finally, a nitrene intermediate occurs that leads to the amination product with concomitant 1,2-aryl/-alkyl migration from a boronate complex. A wide range of nitroarenes underwent C-N coupling with aryl-/alkylboronic acids providing high yields.
Light-Promoted C–N Coupling of Aryl Halides with Nitroarenes
Li, Gang,Yang, Liu,Liu, Jian-Jun,Zhang, Wei,Cao, Rui,Wang, Chao,Zhang, Zunting,Xiao, Jianliang,Xue, Dong
supporting information, p. 5230 - 5234 (2021/02/05)
A photochemical C–N coupling of aryl halides with nitroarenes is demonstrated for the first time. Catalyzed by a NiII complex in the absence of any external photosensitizer, readily available nitroarenes undergo coupling with a variety of aryl halides, providing a step-economic extension to the widely used Buchwald–Hartwig C–N coupling reaction. The method tolerates coupling partners with steric-congestion and functional groups sensitive to bases and nucleophiles. Mechanistic studies suggest that the reaction proceeds via the addition of an aryl radical, generated from a NiI/NiIII cycle, to a nitrosoarene intermediate.
Cu-ACP-Am-Fe3O4@SiO2: an efficient and recyclable heterogeneous catalyst for the Chan–Lam coupling reaction of boronic acids and amines
Vibhute, Sandip P.,Mhaldar, Pradeep M.,Gaikwad, Dipak S.,Shejwal, Rajendra V.,Pore, Dattaprasad M.
, p. 87 - 92 (2020/01/03)
Abstract: We have developed an efficient method for Cu-ACP-Am-Fe3O4@SiO2 catalyzed Chan–Lam coupling of phenylboronic acid with primary amine furnished secondary amines. The catalyst offered virtues like mild reaction conditions, magnetically separable, and reusable and exhibits excellent performance in terms of good product yield and high turnover number. Graphic abstract: [Figure not available: see fulltext.]
Copper immobilized at a covalent organic framework: An efficient and recyclable heterogeneous catalyst for the Chan-Lam coupling reaction of aryl boronic acids and amines
Han, Yi,Zhang, Mo,Zhang, Ya-Qing,Zhang, Zhan-Hui
, p. 4891 - 4900 (2018/11/21)
A polyimide covalent organic framework (PI-COF) with high thermal and chemical stabilities has been readily prepared from commercially available and inexpensive reagents and was employed as an effective support for heterogeneous copper. It was demonstrated that the obtained Cu@PI-COF is a highly active heterogeneous catalyst which can effectively promote the Chan-Lam coupling reaction of aryl boronic acids and amines in an open flask without the aid of any base or additive. In addition, the catalyst could be readily recovered from the reaction mixture by simple filtration and reused for at least eight cycles without any observable change in structure and catalytic activity.
Copper-Catalyzed para-Selective C-H Amination of Electron-Rich Arenes
Berzina, Beatrise,Sokolovs, Igors,Suna, Edgars
, p. 7008 - 7014 (2015/11/23)
A one-pot two-step method for para-selective C-H amination of carbocyclic arenes comprises the in situ formation of unsymmetrical diaryl-λ3-iodanes followed by their Cu(I)-catalyzed reaction with a range of N-unprotected amines.
Redox- And protonation-induced fluorescence switch in a new triphenylamine with six stable active or non-active forms
Quinton, Cassandre,Alain-Rizzo, Valrie,Dumas-Verdes, Ccile,Miomandre, Fabien,Clavier, Gilles,Audebert, Pierre
, p. 2230 - 2240 (2015/01/30)
The synthesis, photophysical and electrochemical properties as well as theoretical calculation studies of a newly designed triphenylamine derivative are described. This original compound displays one neutral form, three oxidized forms, and two protonated
Design of new tetrazine-triphenylamine bichromophores - Fluorescent switching by chemical oxidation
Quinton, Cassandre,Alain-Rizzo, Valerie,Dumas-Verdes, Cecile,Clavier, Gilles,Miomandre, Fabien,Audebert, Pierre
scheme or table, p. 1394 - 1403 (2012/04/17)
Original new fluorescent and electroactive compounds have been prepared, which feature two different fluorescent groups linked through an oxygen atom spacer. We describe here the synthesis, photophysical and electrochemical properties and their interplay, and our theoretical calculations. These molecules are composed of two fluorophores, an electron-rich triphenylamine unit and an electron-poor tetrazine unit. Although the bichromophores are not fluorescent in the neutral state due to a photoinduced electron transfer from the triphenylamine unit to the tetrazine unit, one can restore the fluorescence by oxydation of the triphenylamine moiety. Thus, a redox-fluorescent switch has been realized. Tetrazine-triphenylamine bichromophores linked by an oxygen atom were designed and synthesized. Their photophysical and electrochemical properties were investigated. These dyads are nonfluorescent compounds in their neutral state because of phoinduced electron transfer. However, tetrazine fluorescence was restored by chemical oxidation (cation radical formation). Copyright
Nucleophilic substitutions and radical reactions of phenylazocarboxylates
Jasch, Hannelore,Hoefling, Sarah B.,Heinrich, Markus R.
, p. 1520 - 1532 (2012/03/11)
tert-Butyl phenylazocarboxylates are versatile building blocks for synthetic organic chemistry. Nucleophilic substitutions of the benzene ring proceed with aromatic amines and alcohols under mild conditions. The attack of aliphatic amines may be directed to the aromatic core as well as to the carbonyl unit leading to azocarboxamides. The benzene ring can further be modified through radical reactions, in which the tert-butyloxycarbonylazo group enables the generation of aryl radicals at either elevated temperatures or under acidic conditions. Radical reactions include oxygenation, halogenation, carbohalogenation, carbohydroxylation, and aryl-aryl coupling.
4-substituted tert-butyl phenylazocarboxylates-synthetic equivalents for the para-phenyl radical cation
Hoefling, Sarah B.,Bartuschat, Amelie L.,Heinrich, Markus R.
supporting information; experimental part, p. 9769 - 9772 (2011/02/22)
First electrophile, then radical: 4-Substituted tert-butyl phenylazocarboxylates 1 are versatile synthetic equivalents of the para-phenyl radical cation 2. The tert-butyloxycarbonylazo group enables nucleophilic substitutions to proceed under mild conditions and can later be employed for the generation of aryl radicals. Copyright
A general animation method based on the addition of polyfunctional arylmagnesium reagents to functionalized arylazo tosylates
Sapountzis, Ioannis,Knochel, Paul
, p. 897 - 900 (2007/10/03)
A one-pot reaction sequence consisting of a Grignard reaction, allylation, and reduction provides new functionalized diarylamines in good yields (see scheme, Ts = toluene-4-sulfonyl, NMP = N-methylpyrrolidine, TFA = trifluoroacetic acid). In the first ste
