反应详情

6-Bromo-1-cyclohexyl-3-ethyl-1H-indazole (1.015 g, 3.304 mmol) was dissolved in toluene (10 mL) and to the solution was added hydrobromic acid (1.5 mL of a 30% solution in acetic acid). The solution was stirred at room temperature 30 minutes and concentrated to low volume. Ethyl acetate (10 mL) was added, the solids were filtered and washed with additional ethyl acetate (10 mL) to provide 6-bromo-1 cyclohexyl-3-ethyl-1H-indazole hydrobromide (1.612 g, 80%) as a white solid (mp 170-172° C. (decomposition)). 1H NMR (400 MHz, DMSO) δ 1.24 (t, 3, J=7.5), 1.42-1.45 (m, 2), 1.64 (d, 1, J=12.9), 1.76-1.87 (m, 7), 2.85 (q, 2, J=7.5), 4.46-4.52 (m, 1), 7.14 (dd, 1, J=8.5, 1.5), 7.63 (dd, 1, J=8.5, 0.8), 7.93 (d, 1, J=1.0), 9.93 (bs, 1). 13C NMR (100 MHz, DMSO) δ 13.99, 20.23, 25.47, 32.70, 56.67, 112.69, 119.90, 121.06, 122.42, 122.98, 140.57, 146.18.

1. concentrationconcentrated to low volume
2. additionEthyl acetate (10 mL) was added
3. filtrationthe solids were filtered
4. washwashed with additional ethyl acetate (10 mL)