Water → 5-(2-fluorophenyl)-7-methylimidazo[5,1-f][1,2,4]triazin-4(3H)-one

Participants

Reaction Conditions

Reaction Steps

Compound C4 (8.16 g, 37.4 mmol) in tetrahydrofuran (187 mL) was heated to 55° C., treated with 1,1′-carbonyldi(1,2,4-triazole) (7.36 g, 44.8 mmol) and stirred at 55° C. for 5 hours. The reaction was then cooled and stirred for an additional 3 days at room temperature. Removal of solvent in vacuo gave a solid, which was stirred with water (200 mL) for 1 hour and filtered to afford a pale brown powder. This was stirred in heptane (˜35 mL) and ethyl acetate (˜35 mL) for 24 hours and filtered, providing the product as an off-white powder (5.08 g). The aqueous filtrate was extracted once with ethyl acetate; this organic layer was dried over magnesium sulfate, filtered and concentrated under reduced pressure. The residue was recrystallized from heptane/ethyl acetate to provide additional product as a white powder. Total yield: 5.33 g, 21.8 mmol, 58%. LCMS m/z 245.0 [M+H]+. 1H NMR (500 MHz, CD3OD) δ 7.73 (s, 1H), 7.62 (ddd, J=7.6, 7.3, 1.7 Hz, 1H), 7.40-7.46 (m, 1H), 7.24 (ddd, J=7.6, 7.6, 1.0 Hz, 1H), 7.18 (br dd, J=10, 8.5 Hz, 1H), 2.63 (s, 3H).

Provenance & Evidence