Potassium Hydroxide → 7-Aminothieno[2,3-b]pyrazine-6-carboxylic acid

Participants

Reaction Steps

A solution of ethyl 7-aminothieno[2,3-b]pyrazine-6-carboxylate 7 (10 g, 44.8 mmol) and potassium hydroxide (5.0 g, 90 mmol) in THF (50 mL), ethanol (50 mL) and water (20 mL) was stirred at 70° C. for 2 h. Quenched in a cold solution of 2N HCl, and the resulting precipitate was collected to give crude 7-aminothieno[2,3-b]pyrazine-6-carboxylic acid 8 (8.59 g, 98%). 1H-NMR (400 MHz, DMSO-d6) 7.03 (br s, 2H), 8.77 (s, 2H), 12.8 (br s, 1H).

Provenance & Evidence