反应详情

A mixture of 5-bromo-indole-3-carboxaldehyde (5 g, 22.3 mmol), diammonium hydrogen phosphate (15.6 g, 31.8 mmol) in 1-nitropropane (66 mL) and acetic acid (22 mL) were heated at reflux for 16 h. After cooling to room temperature, the solvents were removed under reduced pressure and water added to the dark residue. After a short while, 5-bromo-1H-indole-3-carbonitrile precipitated rapidly. The solid was filtered, washed severally with water and dried for several hours to afford 4.3 g (86%) of the desired product. 1H-NMR (CD3OD) δ 7.40 (m, 2H), 7.77 (s, 1H), 7.97 (s, 1H). Mass spec.: 222.95 (MH)+.

1. temperaturewere heated
2. temperatureat reflux for 16 h
3. customthe solvents were removed under reduced pressure and water
4. additionadded to the dark residue
5. customAfter a short while, 5-bromo-1H-indole-3-carbonitrile precipitated rapidly
6. filtrationThe solid was filtered
7. washwashed severally with water
8. customdried for several hours