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We highlight key contributions in the field of direct radical CAr− H (hetero)aromatic functionalization involving fluorinated radicals. A compilation of Functional Group Transfer Reagents and their diverse activation mechanisms leading to the release of radicals are discussed. The substrate scope for each radical is analyzed and classified into three categories according to the electronic properties of the substrates. Density functional theory computational analysis provides insights into the chemical reactivity of several fluorinated radicals through their electrophilicity and nucleophilicity parameters. Theoretical analysis of their reduction potentials also highlights the remarkable correlation between electrophilicity and oxidizing ability. It is also established that highly fluorinated radicals (e.g. ⋅OCF3) are capable of engaging in single‐electron transfer (SET) processes rather than radical addition, which is in good agreement with experimental literature data. A reactivity scale, based on activation barrier of addition of these radicals to benzene is also elaborated using the high accuracy DLPNO‐(U)CCSD(T) method. [ABSTRACT FROM AUTHOR]

Demonstrated herein is the construction of trifluoromethylated quaternary carbon centers by an asymmetric radical transformation. Enantioenriched trifluoromethylated oxindoles were accessed using a hypervalent iodine‐based trifluoromethyl transfer reagent in combination with a magnesium Lewis acid catalyst and PyBOX‐type ligands to achieve up to 99 % ee and excellent chemical yields. Mechanistic studies were performed by experimental and computational methods and suggest a single‐electron transfer induced SN2‐type mechanism. This example is thereby the first report on the construction of enantioenriched trifluoromethylated carbon centers using hypervalent iodine‐based reagents proceeding through such a reaction pathway. Taming the CF3 radical: A unique single‐electron transfer (SET) induced SN2‐type reaction enables the construction of enantioenriched trifluoromethylated oxindoles using a hypervalent iodine‐based trifluoromethyl transfer reagent. A combination of magnesium Lewis acid catalysis and PyBOX‐type ligands successfully tames the highly reactive CF3 radical to achieve excellent enantioselectivities. [ABSTRACT FROM AUTHOR]