64064-71-7

GENERAL STEPS: 6-Bromoimidazo[1,2-a]pyridine (100 mg, 0.508 mmol) was dissolved in concentrated H2SO4 (0.4 mL) and concentrated HNO3 (0.12 mL, 2.69 mmol) was slowly added at room temperature. The reaction mixture was stirred for 15 min and then the reaction was quenched by the addition of ice water. The resulting solid (123 mg, 99% yield) was collected by filtration and used for subsequent reactions without further purification. The product was characterized by 1H NMR (500 MHz, DMSO-d6): δ 9.40 (t, J = 1.4 Hz, 1H), 8.78 (s, 1H), 8.00-7.85 (m, 2H); mass spectrometry (ESI) showed that the [M + H]+ peaks were located at 242.1/244.1.

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