Ethyl bromopyruvate → ethyl imidazo[1,2-a]pyrazine-2-carboxylate

Temperature

27.5 °C

Ethyl bromopyruvate (2.15 g, 11.04 mmol) was added to stirred solution of 2-aminopyrazine (1 g, 10.5 mmol) in 1,2-Dimethoxy ethane (10 mL). The reaction mixture was stirred at 20-35° C. for 2 h. The mixture was then filtered to obtain a solid precipitate which was dried well, dissolved in EtOH (10 mL) and refluxed for 2 h. This mixture was concentrated, diluted with aqueous saturated sodium bicarbonate solution, extracted with chloroform. The chloroform layer was washed with water followed by brine solution, dried over anhydrous sodium sulphate and concentrated under reduced pressure to afford the crude product, which was purified by column chromatography (using 60-120 silica gel and 60% EtOAc in Hexane as eluent) to afford 450 mg of the title compound.

1. filtrationThe mixture was then filtered
2. customto obtain a solid precipitate which
3. customwas dried well
4. dissolutiondissolved in EtOH (10 mL)
5. temperaturerefluxed for 2 h
6. concentrationThis mixture was concentrated
7. additiondiluted with aqueous saturated sodium bicarbonate solution
8. extractionextracted with chloroform
9. washThe chloroform layer was washed with water
10. dry with materialdried over anhydrous sodium sulphate
11. concentrationconcentrated under reduced pressure
12. customto afford the crude product, which
13. customwas purified by column chromatography (using 60-120 silica gel and 60% EtOAc in Hexane as eluent)

ORD record

ord-fb733e8ddf7f45518a74c262b2842b20

Source dataset

uspto-grants-2015_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09045479B2