反应详情

Using the procedure to synthesize Example 12 and using reagents 3-(3-chloro-6-hydroxy-benzo[b]thiophen-2-ylmethyl)-1-cyclohexyl-pyrrolidin-2-one (175 mg, 0.481 mmol), 4-bromo-butyric acid tert-butyl ester (215 mg, 0.962 mmol), sodium iodide (72 mg, 0.481 mmol), and cesium carbonate (1.25 g, 3.85 mmol) afford crude 4-[3-chloro-2-(1-cyclohexyl-2-oxo-pyrrolidin-3-ylmethyl)-benzo[b]thiophen-6-yloxy]-butyric acid tert-butyl ester. Dissolve ester in trifluoroacetic acid (25 mL) and stir for 1.5 hr. Evaporate and dissolve in 1M NaOH and wash with ether. Bring aqueous layer to a pH of ˜2 with 6M HCl, filter, and dry. Purified on silica gel (30-50% ethyl acetate in hexanes) to give the title compound (105 mg, 49%) as a tan solid: Mass spectrum (apci) m/z=450.1 (M+H).

1. customto synthesize Example 12