Electrosynthesis has made a revival in the field of organic chemistry and, in particular, radical-mediated reactions. Herein, we report a simple directed, electrochemical C−H fluorination method. Employing a dabconium mediator, commercially available Selectfluor, and RVC electrodes, we provide a range of steroid-based substrates with competent regioselective directing groups, including enones, ketones, and hydroxy groups, as well as never reported before lactams, imides, lactones, and esters.A resurgence of organic electrosynthesis has recently been observed after a long period of comparative stasis. 1 Recently, the drive for green, inexpensive methodology in conjunction with the emergence of novel radical/electron transfer-based reactions has permitted the field to blossom. 2 Nevertheless, relatively few methods have been developed to functionalize unactivated C(sp 3 )-H bonds. 3 Notable advances in the development of electrochemical conditions 4 that serve as guiding precedents for C−H oxidation processes 5 have been made by Baran 6 and others. 7 Herein, we report electrochemical, directed fluorination 8 of unactivated sp 3 C−H bonds with ketones, enones, and show proof of concept that imides, lactams, lactones, hydroxy groups, and esters are exploitable as directing groups as well (Scheme 1).Our mechanistic investigation of carbonyl-directed fluorination led us to the discovery that a Selectfluor radical dication (SRD) 9 can act as a coordinated hydrogen atom abstraction agent (Scheme 2). 10 Consequently, we envisioned that electrolysis could directly access this reactive intermediate (SRD) by employing the amine salt compound 1, 1-(chloromethyl)-4-aza-1-azoniabicyclo[2.2.2]octane tetrafluoroborate, as a promotor. 11 Ultimately, we found that using this amine, Selectfluor, and MeCN with RVC|RVC 1.8 V for 3 h successfully fluorinates at the predicted site. 12 This voltage was determined in previous work using cyclic voltammetry. Figure 1 demonstrates the observed peak oxidation values for

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We have found that face-to-face π-stacked aromatic rings show the propensity to activate one another toward electrophilic aromatic substitution through direct influence of the probe aromatic ring by the adjacent stacked ring, rather than through the formation of relay or "sandwich complexes." This activation remains in force even when one of the rings is deactivated through nitration. The resulting dinitrated products are shown to crystallize in an extended parallel offset stacked form, in stark contrast to the substrate.