38160-76-8Relevant academic research and scientific papers
Polystyrene stabilized iridium nanoparticles catalyzed chemo- and regio-selective semi-hydrogenation of nitroarenes to N-arylhydroxylamines
Bhattacherjee, Dhananjay,Das, Pralay,Kumar, Ajay,Shaifali,Zyryanov, Grigory V.
, (2021/08/31)
Polystyrene stabilized Iridium (Ir@PS) nanoparticles (NPs) as a heterogeneous catalyst have been developed and characterized by IR, UV–Vis, SEM, TEM, EDX and XRD studies. The prepared Ir@PS catalyst showed excellent reactivity for chemo- and regio-selective controlled-hydrogenation of functionalized nitroarenes to corresponding N-arylhydroxylamine using hydrazine hydrate as reducing source and environmentally benign polyethylene glycol (PEG-400) as green solvent. The present methodology was applied for vast substrate scope and found to be compatible with wide range of reducible functional groups. The reaction performed at 85 °C or ambient temperature and completed within 5–80 minutes. The catalyst can easily be filtered out from reaction mixture and reusable.
Redox-Neutral Selenium-Catalysed Isomerisation of para-Hydroxamic Acids into para-Aminophenols
Chuang, Hsiang-Yu,Schupp, Manuel,Meyrelles, Ricardo,Maryasin, Boris,Maulide, Nuno
supporting information, p. 13778 - 13782 (2021/03/31)
A selenium-catalysed para-hydroxylation of N-aryl-hydroxamic acids is reported. Mechanistically, the reaction comprises an N?O bond cleavage and consecutive selenium-induced [2,3]-rearrangement to deliver para-hydroxyaniline derivatives. The mechanism is studied through both 18O-crossover experiments as well as quantum chemical calculations. This redox-neutral transformation provides an unconventional synthetic approach to para-aminophenols.
Selective Photoinduced Reduction of Nitroarenes to N-Arylhydroxylamines
Kallitsakis, Michael G.,Ioannou, Dimitris I.,Terzidis, Michael A.,Kostakis, George E.,Lykakis, Ioannis N.
supporting information, p. 4339 - 4343 (2020/06/08)
We report the selective photoinduced reduction of nitroarenes to N-arylhydroxylamines. The present methodology facilitates this transformation in the absence of catalyst or additives and uses only light and methylhydrazine. This noncatalytic photoinduced transformation proceeds with a broad scope, excellent functional-group tolerance, and high yields. The potential of this protocol reflects on the selective and straightforward conversion of two general antibiotics, azomycin and chloramphenicol, to the bioactive hydroxylamine species.
Regioselective installation of fluorosulfate (-OSO2F) functionality into aromatic C(sp2)-H bonds for the construction of: Para-amino-arylfluorosulfates
Fang, Wan-Yin,Zha, Gao-Feng,Zhao, Chuang,Qin, Hua-Li
supporting information, p. 6273 - 6276 (2019/06/07)
The construction of para-amino-arylfluorosulfates was achieved through installation of fluorosulfate (-OSO2F) functionality into aromatic C(sp2)-H bonds by the reaction of N-arylhydroxylamine with sulfuryl fluoride (SO2Fs
A Modified System for the Synthesis of Enantioenriched N-Arylamines through Copper-Catalyzed Hydroamination
Ichikawa, Saki,Zhu, Shaolin,Buchwald, Stephen L.
supporting information, p. 8714 - 8718 (2018/07/14)
Despite significant recent progress in copper-catalyzed enantioselective hydroamination chemistry, the synthesis of chiral N-arylamines, which are frequently found in natural products and pharmaceuticals, has not been realized. Initial experiments with N-arylhydroxylamine ester electrophiles were unsuccessful and, instead, their reduction in the presence of copper hydride (CuH) catalysts was observed. Herein, we report key modifications to our previously reported hydroamination methods that lead to broadly applicable conditions for the enantioselective net addition of secondary anilines across the double bond of styrenes, 1,1-disubstituted olefins, and terminal alkenes. NMR studies suggest that suppression of the undesired reduction pathway is the basis for the dramatic improvements in yield under the reported method.
Trifluoromethyl Vinyl Sulfide: A Building Block for the Synthesis of CF3S-Containing Isoxazolidines
Riesco-Domínguez, Alejandra,Van De Wiel, Jeroen,Hamlin, Trevor A.,Van Beek, Bas,Lindell, Stephen D.,Blanco-Ania, Daniel,Bickelhaupt, F. Matthias,Rutjes, Floris P. J. T.
, p. 1779 - 1789 (2018/02/23)
Trifluoromethyl vinyl sulfide, a potential building block for pharmaceutically and agrochemically relevant products, is prepared and used for the first time in high-pressure-mediated 1,3-dipolar cycloaddition reactions with nitrones to synthesize (trifluoromethyl)sulfanyl isoxazolidines.
TRIFLUOROMETHOXYLATION OF ARENES VIA INTRAMOLECULAR TRIFLUOROMETHOXY GROUP MIGRATION
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Page/Page column 62, (2016/05/02)
The present invention provides a process of producing a trifluoromethoxylated aryl or trifluoromethoxylated heteroaryl having the structure: (I), wherein A is an aryl or heteroaryl, each with or without subsutitution; and R1 is -H, -(alkyl), -(alkenyl), -(alkynyl), -(aryl), -(heteroaryl), - (alkylaryl), - (alkylheteroaryl), -NH-(alkyl), -N(alkyl)2, -NH-(alkenyl), -NH-(alkynyl) -NH-(aryl), -NH-(heteroaryl), -O-(alkyl), -O-(alkenyl), -O-(alkynyl), -O-(aryl), -O-(heteroaryl), -S-(alkyl), -S- (alkenyl), -S-(alkynyl), -S-(aryl), or -S-(heteroaryl), comprising: (a) reacting a compound having the structure: (II), with a trifluoromethylating agent in the presence of a base in a first suitable solvent under conditions to produce a compound having the structure: (III); and (b) maintaining the compound produced in step (a) in a second suitable solvent under conditions sufficient to produce the trifluoromethoxylated aryl or trifluormethoxylated heteroaryl having the structure: (I).
Mechanistic studies on intramolecular C-H trifluoromethoxylation of (hetero)arenes via OCF3-migration
Lee, Katarzyna N.,Lei, Zhen,Morales-Rivera, Cristian A.,Liu, Peng,Ngai, Ming-Yu
supporting information, p. 5599 - 5605 (2016/07/06)
The one-pot two-step intramolecular aryl and heteroaryl C-H trifluoromethoxylation recently reported by our group has provided a general, scalable, and operationally simple approach to access a wide range of unprecedented and valuable OCF3-containing building blocks. Herein we describe our investigations to elucidate its reaction mechanism. Experimental data indicate that the O-trifluoromethylation of N-(hetero)aryl-N-hydroxylamine derivatives is a radical process, whereas the OCF3-migration step proceeds via a heterolytic cleavage of the N-OCF3 bond followed by rapid recombination of a short-lived ion pair. Computational studies further support the proposed ion pair reaction pathway for the OCF3-migration process. We hope that the current study would provide useful insights for the development of new transformations using versatile N-(hetero)aryl-N-hydroxylamine synthons.
Trifluoromethoxylation of arenes: Synthesis of ortho- Trifluoromethoxylated aniline derivatives by OCF3 migration
Hojczyk, Katarzyna N.,Feng, Pengju,Zhan, Chengbo,Ngai, Ming-Yu
supporting information, p. 14559 - 14563 (2015/01/09)
Aryl trifluoromethoxylation by a two-step sequence of O-trifluoromethylation of N-aryl-N-hydroxylamine derivatives and intramolecular OCF3 migration is presented. This protocol allows easy access to a wide range of synthetically useful ortho-OCF3 aniline derivatives. In addition, it utilizes bench-stable reagents, is operationally simple, shows high functional-group tolerance, and is amenable to gram-scale as well as one-pot synthesis.Areaction mechanism of a heterolytic cleavage of the N-OCF3 bond followed by recombination of the resulting nitrenium ion and trifluoromethoxide is proposed for the OCF3-migration reaction.
Solid supported platinum(0) nanoparticles catalyzed chemo-selective reduction of nitroarenes to N-arylhydroxylamines
Shil, Arun K.,Das, Pralay
supporting information, p. 3421 - 3428 (2013/12/04)
Solid supported platinum(0) (SS-Pt) nanoparticles were developed as a heterogeneous catalyst following a reduction/deposition method and characterized by SEM, TEM, EDX and XRD analysis. The SS-Pt catalyst was applied in the chemo-selective reduction of nitroarenes to N-arylhydroxylamines using hydrazine hydrate as a hydrogen source. A wide variety of reducible functional groups such as halides, carboxylic acids, esters, amides, nitriles, keto, alkenes, alkynes and N-benzyl were well tolerated under the reaction conditions. This process was further successfully employed in 10 g scale reactions. N-Arylhydroxylamines were further applied for catalyst free synthesis of azoxybenzenes. Moreover, use of PEG-400 as cheap reaction medium, additive free methodology and the recyclability of SS-Pt catalyst up to ten times without significant loss of catalytic activity evidently follow the principles of green chemistry.
