To a solution of (3-{3-[(2-Chloro-3-trifluoromethyl-benzyl)-diphenylethyl-amino]-propoxy}-phenyl)-acetic acid methyl ester (100 mg, 0.17 mmol) in dry THF (50 ml) was added lithium diisopropylamide (1.26 ml, 0.5 mmol) dropwise with cooling to −78° C. After the reaction mixture was stirred at −78° C. for an additional 1 h, diiodo-propane (152 mg, 0.51 mmol) was added. The reaction was warmed to room temperature over 4 h followed by quenching with saturated ammonium chloride (10 ml). Solvent was removed and the residue was partitioned between water and ethyl acetate. The combined organic layers were washed with brine, dried over sodium sulfate and concentrated under vacuum. The residue was purified by silica gel column chromatograph (EtOAc:Hexane/20:80) to give the title compound as an oil (40 mg, 50%). MS m/e 636.2 (M+H)+.
