125192-28-1Relevant articles and documents
Mild C?F Activation in Perfluorinated Arenes through Photosensitized Insertion of Isonitriles at 350 nm
Weidlich, Frauke,Esumi, Naoto,Chen, Dongyang,Mück-Lichtenfeld, Christian,Zysman-Colman, Eli,Studer, Armido
supporting information, p. 376 - 383 (2019/11/19)
Fluorinated compounds have become important in the fields of agrochemical industry, pharmaceutical chemistry and materials sciences. Accordingly, various methods for their preparation have been developed in the past. Fluorinated compounds can be accessed via conjugation with fluorinated building blocks, via C?H fluorination or via selective activation of perfluorinated compounds to give the partially fluorinated congeners. Especially the direct activation of C?F bonds, one of the strongest σ-bonds, still remains challenging and new strategies for C?F activation are desirable. Herein a method for the photochemical activation of aromatic C?F bonds is presented. It is shown that isonitriles selectively insert into aromatic C?F bonds while aliphatic C?F bonds remain unaffected. Mechanistic studies reveal the reaction to proceed via the indirect excitation of the isonitrile to its triplet state by photoexcited acetophenone at 350 nm. Due to the relatively mild light used, the process shows high functional group tolerance and various compounds of the class of benzimidoyl fluorides are accessible from aryl isonitriles and commercially available perfluorinated arenes. (Figure presented.).
Visible-light-induced radical cascade cyclization of oxime esters and aryl isonitriles: Synthesis of cyclopenta[: B] quinoxalines
Yuan, Yao,Dong, Wu-Heng,Gao, Xiao-Shuang,Xie, Xiao-Min,Zhang, Zhao-Guo
, p. 11900 - 11903 (2019/10/11)
A visible-light-induced radical cascade cyclization of aryl isonitriles and cyclobutanone oxime esters for the synthesis of cyclopenta[b]quinoxalines has been accomplished for the first time. The key to the success of this process was the integration of the in situ-formed nitrile radical followed by the cascade radical isonitrile/nitrile insertion-cyclization. The easy introduction of substituents for both substrates and the high functional group tolerance of the reaction make it an efficient strategy to give various quinoxaline derivatives in moderate to good yields.
TEMPO-Catalyzed Aerobic Oxidative Selenium Insertion Reaction: Synthesis of 3-Selenylindole Derivatives by Multicomponent Reaction of Isocyanides, Selenium Powder, Amines, and Indoles under Transition-Metal-Free Conditions
Liu, Huan,Fang, Yi,Wang, Shun-Yi,Ji, Shun-Jun
supporting information, p. 930 - 933 (2018/02/22)
A novel and efficient approach for the selenium functionalization of indoles was developed with selenium powder as the selenium source, catalyzed by 2,2,6,6-tetramethylpiperidinooxy (TEMPO) and employing O2 as the green oxidant. This protocol provides a practical route for the synthesis of 3-selenylindole derivatives and has the advantages of readily available starting materials, mild reaction conditions, and a wide scope of substrates. Electron spin-resonance (ESR) studies reveal that the approach involves the formation of nitrogen-centered radicals and selenium radicals via oxidation of in situ generated selenoates.
