反应详情

Methyl isoquinoline-3-carboxylate (9.58 g, 51.2 mmol) in concentrated H2SO4 (100 mL) at 0° C. was treated with sodium nitrate (4.79 g, 56.4 mmol) in small portions such that the temperature was maintained below 5° C. Ten minutes after addition was complete, the reaction mixture was allowed to warm to room temperature and stirred for 2 hours. The mixture was poured over ice and adjusted to pH between 7 and 8 and filtered to afford the title compound as a bright yellow solid (11.44 g, 96%). MS (ESI+) m/z 233 (M+H)+; 1H NMR (DMSO, 300 MHz) δ 3.97 (s, 3H), 8.06 (t, J 8.2, 1H), 8.72 (dt, J 1.0, 8.2, 1H), 8.78 (dd, J 1.0, 7.8, 1H), 9.11 (s, 1H), 9.65 (s, 1H).

1. temperaturewas maintained below 5° C
2. additionTen minutes after addition
3. additionThe mixture was poured over ice
4. filtrationfiltered