“…To a solution of 9 (0.260 g, 0.69 mmol) in dichloromethane (10 mL), was added 1,8-diazabicyclo [5,4,0.530 g,3.48 mmol). The reaction mixture was then stirred at room temperature for 6 h. After the reaction was complete, dichloromethane (20 mL) and dilute aqueous HCl solution (2 N, 25 mL) were added, and stirring was continued for 15 min.…”