392-83-6Relevant articles and documents
Cross-Coupling through Ag(I)/Ag(III) Redox Manifold
Demonti, Luca,Mézailles, Nicolas,Nebra, Noel,Saffon-Merceron, Nathalie
supporting information, p. 15396 - 15405 (2021/10/12)
In ample variety of transformations, the presence of silver as an additive or co-catalyst is believed to be innocuous for the efficiency of the operating metal catalyst. Even though Ag additives are required often as coupling partners, oxidants or halide scavengers, its role as a catalytically competent species is widely neglected in cross-coupling reactions. Most likely, this is due to the erroneously assumed incapacity of Ag to undergo 2e? redox steps. Definite proof is herein provided for the required elementary steps to accomplish the oxidative trifluoromethylation of arenes through AgI/AgIII redox catalysis (i. e. CEL coupling), namely: i) easy AgI/AgIII 2e? oxidation mediated by air; ii) bpy/phen ligation to AgIII; iii) boron-to-AgIII aryl transfer; and iv) ulterior reductive elimination of benzotrifluorides from an [aryl-AgIII-CF3] fragment. More precisely, an ultimate entry and full characterization of organosilver(III) compounds [K]+[AgIII(CF3)4]? (K-1), [(bpy)AgIII(CF3)3] (2) and [(phen)AgIII(CF3)3] (3), is described. The utility of 3 in cross-coupling has been showcased unambiguously, and a large variety of arylboron compounds was trifluoromethylated via [AgIII(aryl)(CF3)3]? intermediates. This work breaks with old stereotypes and misconceptions regarding the inability of Ag to undergo cross-coupling by itself.
Synthesis method of 2-bromo-5-fluorobenzotrifluoride
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Paragraph 0025-0026; 0028-0029; 0031-0032; 0034-0035, (2020/07/15)
The invention relates to a synthesis method of 2-bromo-5-fluorobenzotrifluoride. The synthesis method comprises the following steps: with benzotrifluoride as a raw material, mixing benzotrifluoride with sulfuric acid, potassium bromide, cuprous bromide and a catalyst, and carrying out a bromination reaction to obtain 2-bromobenzotrifluoride; putting the obtained 2-bromobenzotrifluoride into a DMSOsolvent, adding potassium fluoride and KCoF4, and carrying out a fluorination reaction so as to obtain 2-bromo-5-fluorobenzotrifluoride. According to the method, trifluorotoluene is used as the raw material; the method is a brand-new synthetic route; bromination and fluorination conditions are mild; reaction yield is high; used raw materials are easy to purchase and low in price; and thus, the method has relatively high industrial application value.
Cathodic C-H Trifluoromethylation of Arenes and Heteroarenes Enabled by an in Situ-Generated Triflyltriethylammonium Complex
Cantillo, David,Jud, Wolfgang,Kappe, C. Oliver,Maljuric, Snjezana
supporting information, (2019/10/08)
While several trifluoromethylation reactions involving the electrochemical generation of CF3 radicals via anodic oxidation have been reported, the alternative cathodic, reductive radical generation has remained elusive. Herein, the first cathodic trifluoromethylation of arenes and heteroarenes is reported. The method is based on the electrochemical reduction of an unstable triflyltriethylammonium complex generated in situ from inexpensive triflyl chloride and triethylamine, which produces CF3 radicals that are trapped by the arenes on the cathode surface.