Hydrochloric Acid → 3-Chloroisoquinoline

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

3-Aminoisoquinoline (1.44 g, 10 mmol) was suspended in 10M HCl (5 mL) and cooled to 0° C. Sodium nitrite (689 mg, 10 mmol) was added in portions over 5 minutes. The reaction mixture was stirred at 0° C. for 2 hours and allowed to warm to room temperature over 1 hour. The reaction mixture was added carefully to saturated NaHCO3 solution (200 mL) and extracted into ethyl acetate. The insoluble byproduct was removed by filtration and the aqueous layer was re-extracted into ethyl acetate. The combined organics were washed with water and brine, dried (Na2SO4) and concentrated to a brown oil which solidified on standing. Flash chromatography on silica, eluting with dichloromethane, gave the title compound as a white solid (827 mg, 5.05 mmol, 51%). 1H NMR (d6-DMSO, 400 MHz) δ 9.12 (s, 1H), 8.41 (s, 1H), 8.12 (dd, 1H, J=7.5, 1.0 Hz), 7.93-7.90 (m, 1H), 7.84-7.80 (m, 1H), 7.74-7.70 (m, 1H). LCMS (1) Rt=1.79 min; m/z (ESI+) 164 (MH+).

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