In a 100 mL round bottom flask, 15 (0.10 g, 0.23 mmol) was dissolved in C6H6 (50 mL). An ethereal solution of 1M HCl in Et2O (0.23 mL, 0.23 mmol) was added to the solution, and the mixture was allowed to react at RT for 1 h, after which the solvent was removed under reduced pressure to yield an on-off white powder. Yield: 0.080 g, 89%. Mp = 85°C.