Hydrogen Bromide → HCID 118185253, compound

A mixture of 2-bromo-1,1-diethoxyethane (3.21 mL, 20.7 mmol) and 48% aqueous hydrobromic acid (1.0 mL) was stirred at reflux for 2 h. The reaction was then cooled to room temperature and treated with sodium bicarbonate until gas evolution ceased. The mixture was filtered and the filtrate diluted with ethanol (15 mL). To this mixture, 3,5-dibromo-6-methylpyrazin-2-amine VII (3.00 g, 11.2 mmol) was added and the reaction stirred at reflux for 16 h. After this time, the reaction was cooled to room temperature and concentrated under reduced pressure to a volume of approximately 10 mL. The suspension was filtered and the filter cake washed with cold ethanol (5 mL). The filter cake was then taken into water (50 mL) and the pH was adjusted to ˜8 with potassium carbonate. The resulting suspension was filtered and the filter cake dried to a constant weight under vacuum to provide 6,8-dibromo-5-methylimidazo[1,2-a]pyrazine VIII: 1H NMR (400 MHz, CDCl3) δ: 7.90 (s, 1H), 7.72 (s, 1H), 2.74 (s, 3H).

1. temperatureat reflux for 2 h
2. filtrationThe mixture was filtered
3. additionthe filtrate diluted with ethanol (15 mL)
4. stirringthe reaction stirred
5. temperatureat reflux for 16 h
6. temperatureAfter this time, the reaction was cooled to room temperature
7. concentrationconcentrated under reduced pressure to a volume of approximately 10 mL
8. filtrationThe suspension was filtered
9. washthe filter cake washed with cold ethanol (5 mL)
10. filtrationThe resulting suspension was filtered
11. customthe filter cake dried to a constant weight under vacuum

ORD record

ord-8f87c4e686cd486482511845fd52ec0c

Source dataset

uspto-grants-2016_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09290505B2