反应详情

A suspension of 2-bromo-6-thioureidopyridine (3 g, 12.92 mmol) and chloroacetaldehyde (3.28 mL, 25.85 mmol) in ethanol (27 mL) and water (7 mL) was heated at reflux for 4.75 h. The solution was concentrated in vacuo and the residue was diluted with 1 N aqueous NaOH solution at 0° C., stirred for 10 min, and the pH was then adjusted to 8.5 by addition of 6 N aqueous HCl solution. The precipitate was collected by filtration, washed several times with water and dried in vacuo over P2O5 to obtain the titled compound (3.17 g, 96%) as a light yellow solid.

1. temperaturewas heated
2. temperatureat reflux for 4.75 h
3. concentrationThe solution was concentrated in vacuo
4. additionthe residue was diluted with 1 N aqueous NaOH solution at 0° C.
5. additionthe pH was then adjusted to 8.5 by addition of 6 N aqueous HCl solution
6. filtrationThe precipitate was collected by filtration
7. washwashed several times with water
8. dry with materialdried in vacuo over P2O5