To a solution of 11 (30 mg, 0.071 mmol, 1 equiv.) in dry DMF (1 mL) was added TMSCHCl2 (0.032 mL, 0.033 g, 0.212 mmol, 3 equiv.) and HCO2Na (1.5 mg, 0.022 mmol, 0.3 equiv.) at room temperature. The resulting solution was heated to 50 °C using an oil bath and stirred at this temperature for 36 h. Following this time, reaction was cooled to room temperature. Subsequently, MeOH (1 mL) and a 1 M aqueous HCl solution (1 mL) were added. The reaction mixture was stirred at room temperature for 1 h and then poured into saturated aqueous NH4Cl solution (10 mL). After transferring to a separatory funnel, this mixture was extracted with Et2O