Charge a flask with 3-(2,6-dichloro-4-hydroxybenzyl)-1-cyclohexylpyrrolidin-2-one (Example 175) (7.5 g, 22 mmol) dissolve with pyridine (200 mL) and cool to 0° C. under nitrogen. Add Tf2O (10 mL, 26 mmol) slowly and warm to room temperature. Stir at room temperature for 30 minutes. Pour into water (1 L) and extract with ether. Wash ether layer twice with water. Dry over sodium sulfate, filter and concentrate. Purify over silica gel (10% ethyl acetate in hexanes) to yield 8.5 g (82%) of the title compound as a white solid. Mass spectrum (apci) rn/z=474.1 (M+H).
