Hydrazine → 3-Bromo-2-hydrazinopyridine

Temperature

60 °C

To a stirring solution of 3-bromo-2-chloropyridine (8.56 g, 45 mmol) in pyridine (40 mL) was added anhydrous hydrazine (4.0 g, 125 mmol). The resulting mixture was stirred at 60° C. for 24 h. Analysis by HPLC indicated that about 50% of starting material was consumed. Additional hydrazine (4.0 g, 125 mmol) was added and the reaction mixture was stirred at 80° C. for another 16 h (total 40 h). After cooling to room temperature, the resulting white suspension was filtered. The collected solid was washed with water (2×50 mL), and dried in a 50° C. vacuum oven for 16 h to afford 5.13 g (61%) of the title compound as a white solid. HPLC/MS (Method C): retention time=0.38 min, [M+H]+=188.0.

1. customwas consumed
2. stirringthe reaction mixture was stirred at 80° C. for another 16 h (total 40 h)
3. temperatureAfter cooling to room temperature
4. filtrationthe resulting white suspension was filtered
5. washThe collected solid was washed with water (2×50 mL)
6. customdried in a 50° C. vacuum oven for 16 h

ORD record

ord-9274df7f5a914b3c9d170b13fdd5c617

Source dataset

uspto-grants-2012_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08324241B2