In the glovebox, a mixture of 3 and 4 (0.051 g, a 2.3:1 ratio of 3 to 4 gives 0.098 mmol of 3) was suspended in dichloromethane (2 mL). To this stirring suspension was added diethylamine (0.10 g, 1.4 mmol) in dichloromethane (2 mL). The resulting suspension was stirred for 5 min, resulting in dissolution of all the starting material. All volatile materials were then evaporated under reduced pressure, leaving a waxy, yellow solid. Rinsing this solid material with cold acetonitrile (3 × 3 mL) removed soluble impurities, leaving a white solid. The resulting solid was dried under vacuum, giving the product as a white powder (0.035 g, 0.068 mmol, 69% yield relative to 3).