2-(4-(Benzyloxy)-6-methoxybenzofuran-2-yl)-6-methylimidazo[1,2-b]pyridazine → 6-Methoxy-2-(6-methylimidazo[1,2-b]pyridazin-2-yl)benzofuran-4-ol

Participants

Reaction Steps

A solution of 2-(4-(benzyloxy)-6-methoxybenzofuran-2-yl)-6-methylimidazo[1,2-b]pyridazine (Example 39A, 1.00 g, 2.59 mmol) in a mixture of dichloromethane (420 mL) and methanol (150 mL) in a 1 L flask was hydrogenated over. 10% Palladium over carbon (0.30 g, i.e., 30 mg Pd) and under 1 atm of hydrogen for 6 h. The reaction mixture was maintained under vacuum for 2 min and then flushed with nitrogen. The catalyst was filtered and washed with warm dichloromethane-methanol (8:2, 100 mL) and the combined filtrate was concentrated under reduced pressure. The yellow residue was boiled with 1,2-dichloroethane (30 mL) and allowed to stand at room temperature for 18 h. The solid was filtered (contains methanol by NMR) and dried in vacuo at 120° C. for 12 h to give the title material (0.760 g, 99% yield) of a yellow solid. LC (Method A): 1.844 min. 1H NMR (DMSO-d6, 400 MHz) δ ppm: 2.54 (s, 3H), 3.77 (s, 3H), 6.28 (d, J=1.96 Hz, 1H), 6.70 (dd, J=1.96, 1.17 Hz, 1H), 7.20 (d, J=9.39 Hz, 1H), 7.24 (d, J=0.78 Hz, 1H), 8.03 (d, J=9.78 Hz, 1H), 8.50 (s, 1H), 10.10 (br s, 1H).

Provenance & Evidence