General procedure for the synthesis of pyrrolidines 11. N-Benzyl-1methoxy-N-((trimethylsilyl)methyl)methanamine (8) (38.3 mL, 150 mmol) was added to a solution of LiF (3.12 g, 120 mmol) and sultam 1 (21.9 g, 100 mmol) in MeCN (200 mL), and the resulting mixture was stirred at 60 °C for 48 h. The reaction mixture was filtered through a plug of silica gel, washed with EtOAc (200 mL), and the resulting filtrate was concentrated in vacuo. The obtained residue was purified by flash chromatography.