a EDG = electron-donating group. functionalization (triclosan) and access to a range of benzenoid-based scaffolds such as naphthoquinones, 1naphthols, and naphthalenes; including the streamlined synthesis of pharmaceutical derivatives (propranolol). The net dehydrogenation of simple arenes is based on two distinct steps: C-H functionalization and C-H deprotonation/-elimination. Mechanistic analysis via competition and DKIE experiments, as well as DFT reveal that there are both similarities and differences depending on the intermediate (thianthrenium or iodonium) enroute to the aryne. C-H functionalization via thianthrenation is broader in scope than iodination; however, mesityliodonium are more reactive leaving groups than the corresponding thianthrenium. C-H functionalization by both thianthrenation and iodination occur with very high para-selectivity and have small observed DKIE consistent with reversible formation of a Wheland intermediate and fast deprotonation. However, the iodination reaction is especially sensitive to SET events and the formation of aryl radical cations, whereas thianthrenation appears to be largely insensitive to this feature. Aryne formation from aryl thianthrenium salts and aryl(Mes)iodonium salts have distinct reaction pathways. Aryl thianthrenium salts undergo reversible deprotonation to generate a stable zwitterion that proceeds through rate-limiting thianthrenium elimination to produce the aryne. Aryl(Mes)iodonium salts undergo a concerted but asynchronous deprotonation/elimination event to generate the aryne. In both cases, experimental and computational determined DKIE values are consistent with these pathways. We envision that these platforms for generating arynes will engender new synthetic applications of arynes and increase the breadth of arynes that are accessible.