A 250 mL round-bottom flask was charged with a stir bar, compound 3 (6 g, 16.7 mmol, 1 equiv.), THF (40 mL), and cooled to 0 °C using an ice-water bath. Subsequently, the freshly prepared Grignard solution (~0.5 M concentration, 100 mL, ~50 mmol, ~3 equiv.) was added dropwise. The reaction mixture was warmed to room temperature over a period of 7 hours. Following this time, the reaction was cooled to 0 °C using an ice-water bath and quenched by slow addition of a saturated aqueous solution of NH4Cl (100 mL).