3-Aminopyridine → 3-Hydrazinylpyridine dihydrochloride

Participants

Reaction Conditions

Reaction Steps

3-Aminopyridine (20 g) was dissolved in concentrated hydrochloric acid (125 mL), and an a aqueous solution (40 mL) of sodium nitrite (15 g) was added at −10° C. over 20 min. The mixture was stirred at 0° C. for 2 hr. This solution was added to a solution (200 mL) of tin(II) chloride (80 g) in concentrated hydrochloric acid at −2° C. over 20 min. The mixture was stirred for 14 hr. The precipitate was filtered off and ice was added. The mixture was made strongly-basic with a 50% a aqueous potassium hydroxide solution and extracted with dichloromethane. The extract solution was dried and concentrated under reduced pressure. The residue was dissolved in ethyl acetate (400 mL) and 4 mol/L of hydrochloric acid-ethyl acetate (55 mL) was added under ice-cooling. The precipitate was collected by filtration to give 3-hydrazinopyridine dihydrochloride (18 g) as a pale-yellow solid.

Provenance & Evidence