Formic Acid → Methyl 5-methoxy-3-methylpyrazine-2-carboxylate

Participants

Reaction Conditions

Reaction Steps

To a mixture of methyl 6-chloro-5-methoxy-3-methylpyrazine-2-carboxylate (6.5 g, 30.0 mmol) and palladium, 10% wt. on activated carbon (3.19 g, 3.00 mmol) in a 500 mL flask under nitrogen, was added acetone (200 mL) carefully. The flask was cooled to 0° C. and triethylamine (30 mL, 216 mmol) was added followed by formic acid (96%) (5.66 mL, 150 mmol) dropwise. The suspension was warmed to room temperature with stirring and then heated at 40° C. for 1 h. The reaction mixture was concentrated, diluted with saturated sodium hydrogenocarbonate solution and extracted with DCM. The organic layer was dried and concentrated. The crude product was purified by ISCO column chromatography using 0-20% EtOAc in DCM to give methyl 5-methoxy-3-methylpyrazine-2-carboxylate (5.2 g, 95% yield). 1H NMR (300 MHz, CDCl3) δ ppm 8.11 (1H, s), 4.02 (3H, s), 3.97 (3H, s), 2.80 (3H, s)

Provenance & Evidence