125509-82-2Relevant academic research and scientific papers
N-Heterocyclic Carbene Catalyzed Concerted Nucleophilic Aromatic Substitution of Aryl Fluorides Bearing α,β-Unsaturated Amides
Kamitani, Miharu,Tobisu, Mamoru,Yasui, Kosuke
, p. 14157 - 14161 (2019)
Concerted nucleophilic aromatic substitution (CSNAr) has emerged as a powerful mechanistic manifold, in which nucleophilic aromatic substitution can proceed in one step without the need to form a Meisenheimer intermediate. However, all of the CSNAr reactions reported thus far require a stoichiometric strong base or activating reagent, and no catalytic variants have yet been reported. Herein, we report an N-heterocyclic carbene (NHC)-catalyzed intramolecular cyclization of acrylamides that contain a 2-fluorophenyl group on the nitrogen through a CSNAr reaction. By using this catalytic method, it is possible to synthesize an array of quinolin-2-one derivatives, which are common structural motifs in pharmaceuticals and organic materials. DFT calculations unambiguously revealed that this reaction proceeds through the concerted nucleophilic aromatic substitution of aryl fluorides, in which a stereoelectronic σ (Cipso-Cβ)→ σ*(Cipso-F) interaction critically contributes to the stabilization of the transition state for the cyclization.
Copper-Catalyzed Radical N-Demethylation of Amides Using N-Fluorobenzenesulfonimide as an Oxidant
Yi, Xuewen,Yi, Xuewen,Lei, Siyu,Liu, Wangsheng,Che, Fengrui,Yu, Chunzheng,Liu, Xuesong,Wang, Zonghua,Zhou, Xin,Zhang, Yuexia
, p. 4583 - 4587 (2020/05/05)
An unprecedented N-demethylation of N-methyl amides has been developed by use of N-fluorobenzenesulfonimide as an oxidant with the aid of a copper catalyst. The conversion of amides to carbinolamines involves successive single-electron transfer, hydrogen-atom transfer, and hydrolysis, and is accompanied by formation of N-(phenylsulfonyl)benzenesulfonamide. Carbinolamines spontaneously decompose to N-demethylated amides and formaldehyde, because of their inherent instability.
Synthesis of oxindoles via Cu-mediated reactions between N-phenylacrylamides and ethyl 2-bromo-2-methylpropionate
Liu, Da,Zhuang, Shaobo,Chen, Xiang,Yu, Lin,Yu, Yongqi,Hu, Liang,Tan, Ze
supporting information, p. 612 - 616 (2018/01/18)
A novel way of synthesizing alkylated oxindoles via Cu-mediated atom transfer radical addition reaction between N-phenylacrylamides and ethyl 2-bromo-2-methylpropionate has been described. It was found that the use of N,N,N′,N′-1,1,2,2,-tetramethylethylenediamine as ligand was important for achieving good yields. Additionally, the use of DMSO as solvent and running the reaction at 130 °C were also crucial. In some cases, the product can be further brominated when the reaction temperature was raised to 150 °C.
High-valent palladium-promoted formal Wagner-Meerwein rearrangement
Wu, Hongmiao,Yang, Bin,Zhu, Lin,Lu, Ronghua,Li, Guigen,Lu, Hongjian
supporting information, p. 5804 - 5807 (2016/11/29)
An oxy-palladation, formal Wagner-Meerwein rearrangement and fluorination cascade has been established for generating fluorinated oxazolidine-2,4-diones and oxazolidin-2-ones. The reaction has a broad substrate scope in which both aryl and alkyl groups can be utilized as efficient migrating groups. Experimental evidence suggests that the reaction is initiated by anti-oxy-palladation of the olefin, followed by oxidative generation of an alkyl PdIV intermediate and a concerted migration-fluorination.
Synthesis of oxindoles through silver-catalyzed trifluoromethylation-, difluoromethylation- and arylsulfonylation-cyclization reaction of N-arylacrylamides
Liu, Jidan,Zhuang, Shaobo,Gui, Qingwen,Chen, Xiang,Yang, Zhiyong,Tan, Ze
supporting information, p. 3196 - 3202 (2014/06/09)
Efficient synthesis of trifluoromethyl and difluoromethyl-substituted oxindoles was achieved by reacting Langlois reagent or Baran reagent with N-arylacrylamides. However, the reaction of aryl sulfinic acid sodium salts with N-arylacrylamides did not give the desulfinative products, instead, aryl sulfonated products were produced. Copyright
Direct annulations toward phosphorylated oxindoles: Silver-catalyzed carbon-phosphorus functionalization of alkenes
Li, Ya-Min,Sun, Meng,Wang, Hong-Li,Tian, Qiu-Ping,Yang, Shang-Dong
supporting information, p. 3972 - 3976 (2013/05/09)
Silver screen: The AgNO3-catalyzed carbon phosphorylation of alkenes occurs by an alkene addition/cyclization cascade. Ag+ reacts with Ph2P(O)H to form the crucial active intermediate 1, which promotes the reaction. This method requires a cheap, nontoxic silver salt as the catalyst and substrates for the transformation are simple and readily accessible.
