Dimethylformamide → 1-(Imidazo[1,2-b]pyridazin-3-yl)ethan-1-one

Participants

Reaction Conditions

Reaction Steps

3-Bromoimidazo[1,2-b]pyridazine (1.0 g, 5.05 mmol), tributyl(1-ethoxyvinyl)tin (3.41 mL, 10.1 mmol), and PdCl2(PPh3)2 (354 mg, 0.505 mmol), were added to a sealed tube. DMF (25.2 mL) was added and the reaction purged with nitrogen for 5 minutes. The reaction was heated at 100° C. for 18 h. The reaction was cooled to room temperature and quenched with aqueous saturated sodium bicarbonate. The aqueous layer was extracted with ethyl acetate (×3) and the combined organic layers were dried with magnesium sulfate, filtered, and concentrated under reduced pressure. The residue was diluted with methanol (10 mL) and HCl in 1,4-dioxane (1.26 mL, 5.05 mmol, 4M) was added. The solution was stirred at room temperature for 1 h. The reaction was then quenched with aqueous saturated sodium bicarbonate and extracted with ethyl acetate (×3). The combined organic layers were dried with magnesium sulfate, filtered, and concentrated under reduced pressure. The residue was purified by flash chromatography to afford the title compound. 1H NMR (500 MHz, CD3SOCD3) δ 8.76 (d, 1H); 8.55 (s, 1H); 8.31 (d, 1H); 8.49 (dd, 1H); 2.64 (s, 3H). LRMS (APCI) calc'd for (C8H7N3O) [M+H]+, 162.1. found 162.1.

Provenance & Evidence