Ethanol → [1,2,4]Triazolo[1,5-a]pyrazin-2-amine

Temperature

65 °C

A 250-mL single-neck round-bottomed flask equipped with a magnetic stirrer and a reflux condenser was charged with 270a (6.00 g, 26.43 mmol, 1.0 eq.), hydroxylamine hydrochloride (3.32 g, 47.52 mmol, 1.8 eq.), DIPEA (12 mL), ethanol (40 mL), and methanol (40 mL). The reaction mixture was stirred at 65° C. for 16 hours. After the reaction was complete, it was cooled to room temperature and concentrated to a volume of around 20 mL under reduced pressure. The resulting suspension was collected by filtration and the solid was washed with 60:1 dichloromethane/ethanol (50 mL) to afford 270b (3.3 g, 92%) as a white solid. MS-ESI:[M+H]+ 136.3. 1H NMR (500 MHz, DMSO-d6) δ 8.84 (d, J=1.0 Hz, 1H), 8.70 (dd, J=1.0, 4.0 Hz, 1H), 7.98 (d, J=5.0 Hz, 1H), 6.47 (s, 2H).

1. customA 250-mL single-neck round-bottomed flask equipped with a magnetic stirrer and a reflux condenser
2. temperatureit was cooled to room temperature
3. concentrationconcentrated to a volume of around 20 mL under reduced pressure
4. filtrationThe resulting suspension was collected by filtration
5. washthe solid was washed with 60:1 dichloromethane/ethanol (50 mL)

ORD record

ord-99a25802158d412b8fa17933b7b8bd19

Source dataset

uspto-grants-2016_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09238655B2