反应详情

A mixture of (RS)-1-[2-(tert-butoxycarbonylamino)propyl]-3-methylindazole (1.2 g, 4.3 mmol), dichloromethane (15 mL) and trifluoroacetic acid (5 mL) was stirred for 1 h. The mixture was partitioned between aqueous sodium hydroxide solution (2 N, 30 mL) and dichloromethane (3×30 mL). The combined organic extracts were washed with brine (2×), dried (magnesium sulfate) and concentrated in vacuo to give an orange oil. 2-Propanol (5 mL) was added, the mixture was heated to boiling, then fumaric acid (0.5 g, 4.3 mmol) was added. The mixture was cooled to room temperature and filtered. The filter cake was dried in vacuo to give the title compound (0.89 g, 68%) as a pale brown solid: mp 145-147° C.; IR νmax (Nujol/cm−1) 1618, 1510, 1458, 1377, 973, 742 and 652; NMR δH (400 MHz, DMSO-d6) 1.09 (3H, d, J 6.5 Hz), 2.49 (3H, s), 3.56 (1H, m), 4.39 (2H, m), 6.47, (2H, s), 7.09-7.15 (1H, m), 7.36-7.41 (1H, m), 7.62 (1H, d, J 8 Hz) and 7.72 (1H, d, J 8 Hz).

1. customThe mixture was partitioned between aqueous sodium hydroxide solution (2 N, 30 mL) and dichloromethane (3×30 mL)
2. washThe combined organic extracts were washed with brine (2×)
3. dry with materialdried (magnesium sulfate)
4. concentrationconcentrated in vacuo
5. customto give an orange oil
6. temperaturethe mixture was heated
7. filtrationfiltered
8. customThe filter cake was dried in vacuo