81100-29-0Relevant academic research and scientific papers
Unexpected Rearrangement of 2-Bromoaniline under Biphasic Alkylation Conditions
Barraza, Scott J.,Denmark, Scott E.
supporting information, p. 2891 - 2895 (2017/10/06)
Alkylation of 2-bromoaniline with benzyl bromide under ostensibly basic N-alkylation conditions resulted in migration of bromine from the 2- to the 4-aryl position. Herein we report our studies to elucidate the mechanism of this rearrangement with the objective of suppressing this unexpected outcome. We find that careful choice of reagents is critical, and that this behavior may be extrapolated to alkylation reactions of electron-rich bromo- and iodoanilines in general.
Cs2CO3-Promoted Direct N-Alkylation: Highly Chemoselective Synthesis of N-Alkylated Benzylamines and Anilines
Castillo, Juan-Carlos,Orrego-Hernández, Jessica,Portilla, Jaime
, p. 3824 - 3835 (2016/08/20)
Herein is described an efficient and chemoselective method for the synthesis of diversely substituted secondary amines in yields up to 98 %. Direct mono-N-alkylation of primary benzylamines and anilines with a wide range of alkyl halides is promoted by a cesium base in the absence of any additive or catalyst. The basicity and solubility of cesium carbonate in anhydrous N,N-dimethylformamide not only enables mono-N-alkylation of primary amines but also suppresses undesired dialkylation of the desired amines.
Room-Temperature Practical Copper-Catalyzed Amination of Aryl Iodides
Deldaele, Christopher,Evano, Gwilherm
, p. 1319 - 1328 (2016/04/20)
An efficient and highly practical procedure is reported for the Ullmann-Goldberg-type copper-catalyzed amination of aryl iodides. By using a combination of copper iodide and proline in the presence of an excess of an amine, a wide range of aryl iodides can be readily aminated at room temperature. The reaction proceeds well regardless of the electronic properties of the starting aryl iodide and the amination products can be obtained without the need for purification by column chromatography in most cases. Owing to its efficiency and the mildness of the reaction conditions, this amination could also be extended to the amination of complex aryl iodides at room temperature.
Reactions of arenediazonium o-benzenedisulfonimides with aliphatic triorganoindium compounds
Barbero, Margherita,Cadamuro, Silvano,Dughera, Stefano,Ghigo, Giovanni
scheme or table, p. 862 - 868 (2009/04/11)
The reaction of various arenediazonium o-benzenedisulfonimides with aliphatic triorganoindium compounds is described. Surprisingly, with triethyl- or tributylindium we obtained N-ethyl- or N-butylanilines, respectively. This is the first case in which, at least formally, the reactive site of a diazonium salt is the nitrogen atom directly bonded to the aromatic ring. In contrast, with trimethylindium we obtained only formaldehyde (aryl)hydrazones. In order to explain the difference between trimethyl- and triethylindium we have proposed some reaction mechanisms, supported by detailed density functional (DFT) calculations. The possible role of diazene/hydrazone tautomerism initially assumed was discarded and therefore three mechanisms for the key step (nucleophilic addition of the trialkylindium to the N=N double bond of diazene) were studied. For the favoured mechanism there is a difference in the energy barriers of 2 kcalmol-1 between the reactions with trimethyl- and triethylindium. This difference is explained on the basis of the different C-In bond energies in the two organometallics and it is assumed to be enough to explain their different behaviour under the experimental conditions. Wiley-VCH Verlag GmbH & Co. KGaA, 2008.
A mild inter- and intramolecular amination of aryl halides with a combination of CuI and CsOAc
Kubo, Tetsuji,Katoh, Chiharu,Yamada, Ken,Okano, Kentaro,Tokuyama, Hidetoshi,Fukuyama, Tohru
experimental part, p. 11230 - 11236 (2009/04/11)
A unique combination of CuI and CsOAc was found to catalyze aryl amination under mild conditions. The reaction takes place at room temperature or at 90 °C with broad functional group compatibility. The intramolecular reaction was able to form five-, six-, and seven-membered rings with various protecting groups on the nitrogen atom. The scope of the intermolecular amination, as well as its applications to unsymmetrical N,N′-dialkylated phenylenediamines, was investigated.
Aqueous-mediated N-alkylation of amines
Singh, Chingakham B.,Kavala, Veerababurao,Samal, Akshaya K.,Patel, Bhisma K.
, p. 1369 - 1377 (2008/09/17)
Direct N-alkylation of primary amines to secondary/tertiary amines and of secondary amines to tertiary amines has been achieved in excellent yields by employing alkyl, benzylic and allylic halides in the presence of NaHCO 3 in an aqueous medium at an elevated temperature. Amines of different stereoelectronic nature react with ease with different halides. The selective formation of secondary amines and the formation of three different substituted tertiary amines are some of the interesting features of this methodology. Reaction in an aqueous medium, operationally convenient conditions, excellent yields and innocuous byproducts, and the absence of transition-metal catalysts, expensive bases, solid supports and the formation of undesired quaternary ammonium salts makes this method a green chemical process. Wiley-VCH Verlag GmbH & Co. KGaA, 2007.
Synthesis of Secondary Arylamines through Copper-Mediated Intermolecular Aryl Amination
Okano, Kentaro,Tokuyama, Hidetoshi,Fukuyama, Tohru
, p. 4987 - 4990 (2007/10/03)
(Equation presented) A mild intermolecular copper-mediated amination of aryl iodides has been developed. The reaction takes place at room temperature or heating at 90°C and tolerates halogens attached to the aromatic ring. Its synthetic applications include a synthetic protocol for unsymmetrical N,N′-dialkylated phenylenediamines and both a stepwise and a general synthetic method for N-aryl secondary amines via Ns-anilides (readily obtained by reaction of the Ns-amide).
A general procedure to selectively prepare N-alkylanilines by an unexpected reaction of (Z)-(tert-butylsulfanyl)(aryl)diazenes with alkyllithium reagents
Barbero, Margherita,Degani, Iacopo,Dughera, Stefano,Fochi, Rita
, p. 742 - 750 (2007/10/03)
A general procedure has been set up to prepare, selectively, the N-monoalkylanilines 7, reacting (Z)-(tert-butylsulfanyl)(aryl)diazenes 3 with alkyllithium 6 (MeLi, BuLi, s-BuLi, n-C6H13Li). The reactions were carried out in anhydrous diethyl ether at 0°C or - 78°C, depending on the reagent 6, and then at room temperature. In optimal conditions the yields of the pure products 7 (uncontaminated by dialkylation products) were from good to excellent: for 38 considered examples, 34 were positive with yields varying between 61percent and 91percent (average yield 78percent). Collateral proofs were carried out to support a hypothesized reaction mechanism.
