We hypothesize that Lewis acid-enhanced Brønsted acidity can render unactivated secondary alcohols reactive in Friedel-Crafts chemistry. 3-tert-Butylphenol (1a) and cyclohexanol (2a) were selected to test for reactivity since they are readily available and conversion to product could be conveniently quantified by NMR analysis (Table ). Catalytic amounts of Fe(III) salts (2.5 mol%) were initially examined with stoichiometric quantities of HCl (2 equiv) at 140 °C. The desired alkylation product (3aa) was formed in 50-57% NMR yields (entries 1-2). Of all the Lewis acid catalysts tested, including Zn(OAc)2 and Fe(II) salts (see SI), ZnCl2 performed the best, providing the product in 63% yield (entry 3). Lowering the temperature from 140 °C to 120 °C was detrimental to yield (39%, entry 4), and increasing the ZnCl2 loading to 5 mol% enhanced product formation (71%, entry 5). However, further increasing the amount of Zn-catalyst to 30 mol% does not improve the reaction outcome (entry 6). CSA is found to be effective at supporting this transformation, albeit providing a lower yield even when cyclohexanol (2a) was employed as the solvent (39%, entry 7). Solid CSA is desirable because it addresses the concern of volatile HCl escaping from the reaction vessels at high temperature. Reducing the amount of alkylating agent in the reaction mixture from solvent quantities to 5 equivalents improved the yield to 68% (entry 8). The reactivity is maintained by reducing the amount of CSA from 2 equivalents to 0.75 equivalents, which resulted in an isolated 74% yield of 3aa when using 3 equivalents of alcohol 2a.