A stirred solution of 4-bromophenyl cyclopentyl sulfone (EP683172 A1) (0.5 g) and N,N-diisopropylethylamine (3.33 ml) in DMF (15 ml) was treated with dichlorobis(triphenylphosphine) palladium (II) (50 mg) and copper iodide (13.68 mg). The solution was heated to 70° under nitrogen and a solution of 4-[(6-bromohexyl)oxy]but-1-yne (DE 3513885 A1) and N,N-diisopropylethylamine (1.66 ml) in DMF (5 ml) was added dropwise. The mixture was stirred at 70° for 19 h. The reaction mixture was cooled to room temperature, poured onto water and extracted 3 times with EtOAc. The extracts were dried (MgSO4) and evaporated in vacuo. The residual oil was purified on a silica SPE bond elut cartridge (100 g), using a gradient of 0% to 30% diethyl ether in cyclohexane (Gradmaster™). The appropriate fractions were evaporated to give the title compound (280 mg). LCMS RT=3.93 min
