Reaction Steps
Pd/C (10%, 30.7 mg) was covered with THF (2.0 mL) and ethanol (2.0 mL) and stirred under an atmosphere of hydrogen (balloon pressure) for 15 min at room temperature. Then 262 (334 mg, 0.7 mmol) was added as a solution in THF (4.0 mL). The reaction mixture was stirred for 18 h at room temperature, then filtered through celite. The celite was washed with ethyl acetate (4×5 mL) and the combined filtrates were concentrated in vacuo. The residue was recrystallised from ether/dichloromethane to obtain the title compound as yellow solid (253 mg, 93%). 1H NMR (400 MHz, CDCl3) δ 0.98 (3H, t, J 7.4, CH2CH3), 1.41 (1H, sept, J 7.0, one of CH2CH3), 1.68 (1H, sept, J 6.9, one of CH2CH3), 2.51 (1H, dd, J 16.4, 5.9, one of ArCH2CH), 2.75-2.84 (2H, m, one of ArCH2CH, CHN), 3.51-3.75 (4H, m, 2×ArCH2N), 3.80 (3H, s, OCH3), 3.83 (9H, s, 3×OCH3), 6.44 (1H, s, CH), 6.60 (2H, s, 2×CH), 6.65 (1H, s, CH). 13C NMR (100 MHz, CDCl3) δ 11.1, 23.0, 29.4, 50.8, 55.2, 55.9, 56.0, 58.3, 60.9, 105.3, 108.8, 114.6, 125.4, 126.7, 135.6, 136.5, 143.9, 144.9, 153.1. LC/MS (ES+) tr 1.03 min; m/z 388.13 ((M+H)+, 100%); MeOH/H2O 95:5 (1.0 mL/min), HPLC tr 2.58 min (>97%); CH3CN/H2O 90:10 (1.0 mL/min).