Trifluoroacetic anhydride → 5-Bromo-1,2-dihydroquinolin-2-one

Participants

Reaction Steps

To a solution of 5-bromoquinoline 1-oxide (2.7 g, 12.05 mmol) in DMF (8 mL) was added trifluoroacetic anhydride (8.51 mL, 60.3 mmol) in three portions at 0° C. The reaction was allowed to warm to room temperature where it stirred overnight. At the conclusion of this period, the reaction mixture was poured into a saturated aq. NaHCO3 (100 mL) solution, and extracted with DCM (2×50 mL). The combined organic layers were washed with brine, dried over anhydrous MgSO4, filtered, and concentrated to afford the title compound (2.76 g, 98% yield) as a light yellow solid. LCMS, [M+H]+=223.9. 1H NMR (400 MHz, DMSO-d6) δ 11.98 (s, 1H), 8.05 (d, J=9.8 Hz, 1H), 7.50 (dd, J=8.0 Hz, 1H), 7.44 (t, J=8.0 Hz, 1H), 7.36 (d, J=8.0 Hz, 1H), 6.63 (d, J=9.8 Hz, 1H).

Provenance & Evidence