All reacLons were performed in oven-dried glassware with magneLc sLrring. Air and moisture sensiLve liquids were transferred by syringe. PurificaLon of the reacLon products was carried out by column chromatography using silica gel. VisualizaLon on TLC (analyLcal thin layer chromatography) was achieved by the use of UV light (254 nm). Reagents and solvents were purchased from commercial suppliers and used as received. SyntheLc reacLons were done using oven-dried glassware under an inert atmosphere. Low-resoluLon mass spectra were obtained from an Agilent 6890 gas chromatograph equipped with a 5973 mass-selecLve detector. High-resoluLon mass spectra were obtained from a Bruker Maxis Plus Quadrupole The flourenyl alcohol (1 equiv) was added to an oven dried round bottom flask equipped with a magnetic stirbar. The mixture was thoroughly stirred in 10 mL of chloroform or methylene chloride, after which triflic acid (30 equiv) was added dropwise via syringe. The reaction flask was sealed and allowed to stir overnight at room temperature. The reaction mixture was then quenched on ice and made basic with sodium bicarbonate, and 20 mL of additional methylene chloride was added. The organic layer was washed with water and then brine, allowed to dry over anhydrous sodium sulfate, filtered, and concentrated in vacuo. The residue was purified via silica gel column chromatography, when necessary, to give the spirocyclic product.