N-(4-Bromobutyl)phthalimide → 1-[2-[4-[[2-[4-(4-Aminobutoxy)phenyl]-benzo[b]thiophen-3-yl]methyl]phenoxy]ethyl]-pyrrolidine

Participants

Reaction Steps

To a solution of 1-[2-[4-[[2-(4-hydroxyphenyl)benzo[b]thiophen-3-yl]methyl]phenoxy]ethyl]pyrrolidine (53 mg, 0.123 mmol) in THF (1 mL) was added a solution of potassium bis(trimethylsilyl)amide (0.271 mL of 0.5 M, 1.36 mmol, 1.1 eq.) in toluene at ambient temperature. After 80 min, N-(4-bromobutyl)phthalimide (75 mg, 0.265 mmol, 2.2 eq) was added and the reaction heated at reflux for 18 h. The reaction was cooled to ambient temperature, diluted with ethyl acetate (50 mL) then washed with 10% aqueous sodium bicarbonate (20 mL). The solvent was removed under reduced pressure then the residue purified by flash chromatography (20:1 CHCl3: MeOH then 5:1 CHCl3: MeOH) to give the protected amine as a tan solid (54 mg, 70%) and recovered starting material (8 mg).

Provenance & Evidence