Reaction Steps
A solution of 261 (297 mg, 1.0 mmol) in anhydrous DMF (3.0 mL), DIPEA (263 mg, 2.0 mmol) and 3-methoxybenzyl bromide (222 mg, 1.1 mmol) was heated to 80° C. for 12 h, cooled to room temperature and poured into water (50 mL) and ammonium chloride (saturated, 2 mL). The mixture was extracted with ethyl acetate (2×30 mL). The combined organic layers were dried (MgSO4), filtered and concentrated in vacuo. The residue was purified by flash column chromatography using Flashmaster (SiO2: 20 g, hexane 100% to hexane/ethyl acetate 70:30). The title compound was obtained as pale yellow oil (323 mg, 77%). 1H NMR (270 MHz, CDCl3) δ 1.02 (3H, t, J 7.4, CH2CH3), 1.46 (1H, sept, J 7.2, one of CH2CH3), 1.73 (1H, sept, J 6.8, one of CH2CH3), 2.55 (1H, dd, J 16.2, 6.1, one of ArCH2CH), 2.82 (1H, dd, J 16.2, 5.0, one of ArCH2CH), 2.85-2.98 (1H, m, CHN), 3.61-3.77 (4H, m, 2×ArCH2N), 3.84 (6H, s, 2×OCH3), 5.16 (2H, s, OCH2Ph), 6.52 (1H, s, CH), 6.67 (1H, s, CH), 6.81-6.87 (1H, m, CH), 6.95-7.02 (2H, m, 2×CH), 7.23-7.52 (5H, m, OCH2C6H5), 7.27 (1H, t, J 6.9, CH).
