351-83-7Relevant articles and documents
A Facile Regioselective Aromatic Fluorination of N-Aryl-N-hydroxyamides with Diethylaminosulfur Trifluoride (DAST)
Kikugawa, Yasuo,Matsumoto, Kazuhiro,Mitsui, Kimiyo,Sakamoto, Takeshi
, p. 921 - 922 (1992)
Treatment of N-aryl-N-hydroxyamides with diethylaminosulfur trifluoride (DAST) under conventional reaction conditions results in removal of the hydroxy function and introduction of a fluorine atom at the para position of the aromatic ring, in high yield.
4 - Fluorine substituted aryl amine compound and synthesis method thereof
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Paragraph 0045-0047, (2021/09/22)
The invention discloses a synthesis method of 4 -fluorine substituted aryl amine compound, which comprises the following steps: 1) taking acyl-protected phenylhydroxylamine as a substrate, and generating 4 -fluorine substituted aniline compound under basic conditions by taking sulfonyl fluoride as a fluorine source in a polar solvent. 2) The deprotection is carried out under dilute acid conditions or Pd by catalytic hydrogenation to give the 4 - fluorine-substituted aryl amine compound. 4 - Fluorine substituted aniline compounds which are synthesized by the invention greatly increase the lipophilic property due to the introduction of fluorine atoms, and can be widely applied to preparation of fluorine-containing drugs and pesticide and dye intermediates. , The adopted raw materials are industrial products, are cheap and easily available, and are commercially available. 4 - Fluoroaryl aniline prepared by the method is high in yield, and the product with the purity 90% can be obtained in a yield of more than ≥ 99%. The method is simple to operate and low in cost, is very suitable for industrialization, and can be widely popularized and used.
Ethyl 2-Cyano-2-(2-nitrobenzenesulfonyloxyimino) Acetate (ortho-NosylOXY)-Mediated Double Beckmann Rearrangement of Ketoximes under Microwave Irradiation: A Mechanistic Perception
Dev, Dharm,Kalita, Tapasi,Mondal, Tanmay,Mandal, Bhubaneswar
, p. 1427 - 1435 (2021/01/04)
A method for Beckmann rearrangement using ethyl 2-cyano-2-(2-nitrobenzenesulfonyloxyimino) acetate (o-NosylOXY) under microwave irradiation is reported. Ketoximes (19 examples) are converted to the corresponding amides/lactams with 69–97% yields in ～10 minutes without any Lewis acid or co-catalyst. This is an example of halogen-free organocatalytic Beckmann rearrangement. Nuclear magnetic resonance (NMR)- and high-resolution mass spectrometry (HRMS)-based detailed mechanistic investigation suggest that o-NosylOXY acts as an initiator. Such initiators are reported before based on density functional theory (DFT) calculations. However, we report here the HRMS signatures of two transient intermediates, the nitrilium ion and the nitrilium ion's dimeric species. Rigorous NMR-based investigation of the reaction mechanism is performed. Our results indicate that the reported Beckmann rearrangement proceeds via two consecutive rearrangements. (Figure presented.).
