Reaction Steps
The Standard Procedure 2 was followed by use of 5b (135.1 mg, 0.2315 mmol, 1.0 equiv), potassium carbonate (67.5 mg, 0.488 mmol, 2.1 equiv), and 2-nitroimidazole (6b, 54.3 mg, 0.485 mmol, 2.0 equiv). After workup and purification with column chromatography (80% EtOAc in hexanes as eluant), 7d (121.2 mg, 0.1970 mmol) was obtained in 85% yield as a yellow gummy oil: 1H NMR (CDCl3, 400 MHz) δ 0.81 (d, J=6.4 Hz, 6H, 2×CH3), 1.73 (m, 2H, 2×CH), 2.23-2.29 (m, 2H, 2×ArCH), 2.69-2.74 (m, 2H, 2×ArCH), 3.56-3.86 (m, 21H, 3×OCH3+6×OCH2), 4.12 (t, J=5.0 Hz, 2H, CH2N), 4.56 (t, J=4.8 Hz, 2H, CH2O), 6.62 (s, 1H, ArH), 6.67-6.69 (m, 3H, 3×ArH), 6.75-6.78 (m, 2H, 2×ArH), 7.08 (s, 1H, nitroimidazole C5-H), 7.23 (s, 1H, nitroimidazole C4-H); 13C NMR (CDCl3, 100 MHz) δ 16.05, 16.07, 38.63, 38.68, 39.09, 39.12, 49.71, 55.66, 55.76, 55.82, 68.30, 69.22, 69.58, 70.37, 70.46, 70.47, 70.61, 110.89, 111.56, 112.10, 114.58, 120.82, 121.56, 127.30, 127.86, 134.34, 134.40, 144.57, 146.88, 147.41, 147.77, 148.54; IR (neat) 2925 (s), 2873 (s), 1590 (w), 1538 (m), 1516 (s), 1456 (w), 1361 (s), 1260 (s), 1236 (s), 1029 (s) cm−1; HRMS (FAB) m/z calcd for C32H46N3O9 (M+H)+: 616.3234. found: 616.3231.
