Hydrazine → 3-Bromo-2-hydrazinopyridine

Participants

Reaction Steps

To 3-bromo-2-chloropyridine (1-3) (12.5 g, 65 mmol) in THF (100 mL) was added hydrazine (10.4 g, 10.2 mL, 325 mmol). The mixture was heated to reflux and stirred vigorously for 16 h. An additional portion of hydrazine (5.1 g, 5.0 mL, 159 mmol) was added and the reaction was heated for another 24 h. After cooling, the mixture was concentrated in vacuo, suspended in water (50 mL), and extracted with EtOAc (1×350 mL, 1×50 mL). Combined organic layers were washed with brine (50 mL), dried over MgSO4, filtered, and concentrated in vacuo. The resulting crude product (1-4) was used in the subsequent step without further purification. LC/MS: m/z (M+H)=187.9.

Provenance & Evidence