Potassium Carbonate → 3-[4-(4-Fluorophenyl)piperidin-1-yl]propylphthalimide

Participants

Reaction Conditions

Reaction Steps

A mixture of 4-(4-fluorophenyl)piperidine hydrochloride (5.08 g, 23.2 mmol), 3-bromopropylphthalimide (6.22 g, 23.2 mmol), and potassium carbonate (15 g) in DMF (100 mL) was stirred at 95-100° C. for 12 h. About 80% of the solvent was evaporated under reduced pressure. The residue was diluted with ethyl acetate (200 mL) and washed with brine (3×100 mL) and dried (Na2SO4). The solvent was evaporated from the ethyl acetate solution and the residue was purified by column chromatography (1/1 hexane-ethyl acetate to 100% ethyl acetate), giving crude product (7.50 g, 88%). This crude product was crystallized from isopropanol, giving a white crystalline solid (4.50 g, 1st crop). This material was used in the next step. Concentration of the mother liquor and cooling gave the second crop of desired product (1.0 g). 1H NMR δ 1.43-1.52 (m, 2H), 1.67-1.75 (m, 2H), 1.80-1.96 (m, 4H), 2.33-2.46 (m, 3H), 2.94-2.99 (br d, 2H), 3.78 (t, J=7 Hz, 2H), 6.90-7.04 (m, 4H), 7.70-7.74 (m, 2H), 7.84-7.87 (m, 2H).

Provenance & Evidence