Potassium Carbonate → 5-(5-chloro-2-oxo-2H-pyridin-1-yl)-pyrazine-2-carboxylic acid methyl ester

Participants

Reaction Steps

5-Chloro-2-pyridinol (1.43 g, 11.05 mmol), the bromide from step 1 (2.39 g, 11.05 mmol), copper (0.021 g, 0.33 mmol) and K2CO3 (1.68 g, 12.15 mmol) were heated at 120° C. for 3 hrs. Xylene (2 ml) was added and heating was continued at 1 reflux for 2 hrs. The reaction mixture was cooled, diluted with EtOAc and water and the pH was adjusted to 9 with NH4Cl. The aqueous layer was extracted with EtOAc (2×) and the combined organic extracts were washed with brine, dried (Na2SO4) and evaporated in vacuo. The residue was chromatographed (silica gel, EtOAc: hexanes 20:80 to EtOAc: CH2Cl2 10:90 gradient elution) to afford the title compound as a solid.

Provenance & Evidence