After stirring at 100 °C for 14 hours, 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 CHCl3 (50 mL) and the layers were separated. The aqueous layer was extracted with CHCl3 (3 x 50 mL). The combined organic extracts were washed with brine (150 mL), NaHCO3 (20 mL), dried over anhydrous Na2SO4, filtered, and concentrated under reduced pressure by rotary evaporation to provide a crude orange oil. Purification by flash column chromatography on silica gel (65% EtOAc/hexanes to 100% EtOAc) afforded 10-9 (546 mg, 82%) as a colorless foam.