Sulfuric Acid → 5-Bromo-8-fluoroisoquinolin-3-ol

Participants

Reaction Conditions

Reaction Steps

To N-(5-bromo-2-fluorobenzyl)-2,2-dimethoxyacetamide (12.0 g, 39 mmol) were added concentrated H2SO4 (21 mL) and oleum (30%, 25.0 mL, 394 mmol). The mixture was heated at 85° C. for 2 h. The reaction mixture was cooled to ambient temperature and poured slowly into a cold aqueous satd. solution of NaHCO3 in a beaker with efficient stirring (Note: frothing occurs). The solid that formed was filtered off, washed with water (50 mL), and dried in vacuo to give the title compound as yellow solid. 1H NMR (DMSO-d6, 300 MHz) δ=7.03 (s, 1H), 7.11 (dd, J=7.2, 2.1 Hz, 1H), 7.98 (dd, J=7.2, 2.4 Hz, 1H), 9.15 (s, 1H). MS (ES+): m/z 242.11/244.13 [MH+]. HPLC: tR=2.63 min (ZQ2, polar—5 min).

Provenance & Evidence