7-Cyano-imidazo[1,2-a]pyridine-2-carboxylic acid ethyl ester synthesis

Yield:1354555-26-2 58%

Reaction Conditions:

Stage #1: ethyl Bromopyruvate;4-cyanopyridin-2-amine in tetrahydrofuran at 25; for 24 h;
Stage #2: with acetic acid in tetrahydrofuran; for 16 h;Reflux;

Steps:

1.1 Step 1:- Ethyl-7-cyanoimidazo[l,2-a]pyrkline-2-carboxylate

To a stirred solution of 2-aminoisonicotinonitrile (0.5 g, 4.2 mmol) in tetrahydrofuran (0.5 mL), ethyl bromopyruvate (0.77 mL, 6.1 mmol) was added and stirred for 24 h at 25 °C. Further, to this reaction mixture, acetic acid (1 mL, 17.5 mmol) was added and refluxed for 16 h. The volatiles were removed under reduced pressure, hexane (10 mL) was added to the obtained residue and stirred for 30 min. The precipitate was filtered, washed with hexane (5 mL) and dried under reduced pressure to obtain ethyl 7-cyanoimidazo[l,2-a]pyridine-2-carboxylate (1 g, 58% yield).

References:

WO2020/208510,2020,A1 Location in patent:Page/Page column 70