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

Temperature

27.5 °C

Ethyl bromopyruvate (2.153 g, 11.04 mmol) was added to a solution of 3-aminopyrazine (1 g, 10.51 mmol) in DME (10 mL) and the mixture was stirred continuously at 20-35° C. for 2 h. The reaction mixture was filtered and the solid which precipitated out was dried well, dissolved in EtOH (10 mL) and stirred under reflux for 2 h. This reaction mixture was then concentrated under reduced pressure to obtain a crude residue. The residue was diluted with aqueous sodium bicarbonate solution, and extracted with chloroform. The organic layer separated was washed with water and then with brine solution; dried over anhydrous sodium sulphate and concentrated under reduced pressure to afford the crude product. The crude product was further purified by column chromatography (using Silica gel 60-120 mesh and 60% EtOAc in Hexane as eluent) to afford 450 mg of the title compound the as a yellow solid.

1. filtrationThe reaction mixture was filtered
2. customthe solid which precipitated out
3. customwas dried well
4. dissolutiondissolved in EtOH (10 mL)
5. stirringstirred
6. temperatureunder reflux for 2 h
7. concentrationThis reaction mixture was then concentrated under reduced pressure
8. customto obtain a crude residue
9. extractionextracted with chloroform
10. customThe organic layer separated
11. washwas washed with water
12. dry with materialdried over anhydrous sodium sulphate
13. concentrationconcentrated under reduced pressure
14. customto afford the crude product
15. customThe crude product was further purified by column chromatography (using Silica gel 60-120 mesh and 60% EtOAc in Hexane as eluent)

ORD record

ord-fa9c5bee6553436c99fe114c440fdf2a

Source dataset

uspto-grants-2015_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09045479B2