3-Methylisoquinoline → 3-Methyl-5-nitroisoquinoline

Participants

Reaction Conditions

Reaction Steps

To a 0° C. solution of 3-methylisoquinoline (3.00 g, 20.9 mmol) in concentrated sulfuric acid (35 mL) was added solid potassium nitrate (2.33 g, 23.0 mmol) in four portions. The mixture was stirred 2 hours at 0° C. then was diluted with ice. This mixture was basified (pH 10) with 50% aqueous NaOH extracted with CH2Cl2 (60 mL). The organic phase was washed with brine (25 mL), dried (Na2SO4), filtered, and the volatiles were removed in vacuo. The resulting solid was triturated with 1:1 EtOAc-hexanes, filtered and air-dried to provide the title compound (1.60, 8.78 mmol, 42%) as a yellow solid. 1H NMR (300 MHz, CDCl3) δ 9.30 (s, 1H), 8.53 (dd, J=7.7, 1.1 Hz, 1H), 8.35 (s, 1H), 8.26 (d, J=8.1 Hz, 1H), 7.64 (dd, J=9.9, 5.9 Hz, 1H), 2.80 (s, 3H); MS (ESI) m/z 189 (M+H)+.

Provenance & Evidence