Once the stated time had elapsed, O2 was bubbled through the reaction mixture for 2 minutes. The oil bath temperature was then increased to 100 °C. After stirring at 80 °C for 1 hour, the reaction vessel was removed from the oil bath and allowed to cool to room temperature. Once at room temperature, the reaction mixture was diluted with water (5 mL) and EtOAc (5 mL). The layers were separated, and the aqueous layer was extracted with EtOAc (3 x 5 mL). The combined organic extracts were washed with brine (5 mL x 2 mL), dried over anhydrous Na2SO4, filtered, and concentrated under reduced pressure by rotary evaporation to provide a crude brown oil.