In a round bottom flask containing 5-bromo-2-(1-bromo-ethyl)-3H-pyrimidin-4-one (1.0 g, 3.5 mmol) in acetonitrile (30 ml) was added KI (0.9 g, 5.3 mmol), K2CO3 (1.2 g, 5.3 mmol), and (1-(4-Methoxy-benzenesulfonyl)-piperazine (983 mg, 3.5 mmol). The reaction was heated at reflux for 12 hours. The solution was concentrated under reduced pressure. The residue was partitioned between water (10 ml) and dichloromethane (15 ml). The organic layer was dried over magnesium sulfate, filtered and concentrated under reduced pressure. The solvent was removed under vacuum. The resulting residue purified by column chromatography (ethyl acetate: hexanes 1:1) to give 5-bromo-2-{1-[4-(4-methoxy-benzenesulfonyl)-piperazin-1-yl]-ethyl}-3H-pyrimidin-4-one (Yield 854 mg, 53%). 1H NMR (400 MHz, CDCl3): δ 1.28 (d, J=7.0 Hz, 3H), 2.62-2.49 (m, 4H), 3.00-2.94 (m, 4H), 3.84 (s, 3H), 4.05 (q, 1H, J=7.0 Hz), 6.97 (d, J=11.8 Hz, 2H), 7.62 (d, J=11.8 Hz, 2H), 8.11 (s, 1H). MS m/z calc. 457.3, found (ESI); 457.2 (M+1)+. Retention time 2.50 minutes.
