To a solution of (3R,4R)-1-tert-butyl-3-({3-cyclohexyl-3-[(methylthio)methyl]-8-azabicyclo[3.2.1]oct-8-yl}carbonyl)-4-(2,4-difluorophenyl)pyrrolidinium chloride (3-7) (0.150 g, 0.0270 mmol) in ethanol (6.0 mL) was added a solution of NaIO4 (0.174 g, 0.813 mmol) in 6.0 mL of water. The mixture was stirred at room temperature for 50 min. The solid was filtered and filtrate was concentrated, diluted with methylene chloride, washed with a saturated aqueous solution of Na2SO3. The organic phase was dried over anhydrous Na2SO4, filtered, and concentrated, followed by the addition of one equivalent HCl in ether to afford (3-8) as white solid (m,z (ES) 534 (MH+)).
