Yield: 91%

Reaction Conditions:

with sodium hydride in tetrahydrofuran at 20;

Steps:

2-Chloro-6-ethoxypyrazine
To THF (2 mL) in microwave reaction vessel were added ethanol (0.059 mL, 1.0 mmol) and sodium hydride (32 mg, 1.3 mmol). After stirring for 30 min at room temperature, 2,6-dichloropyrazine (100 mg, 0.671 mmol) was added to the reaction mixture. The reaction mixture was heated in the microwave reactor at power 100 W and 50 °C for 10 min. After solvents were removed under reduced pressure, the residue was dissolved in ethyl acetate. Organic layer was washed with water and dried over MgSO₄. Filtration and removal of solvent of the filtrate provided 97 mg of title compound in 91% yield; 1H NMR (400 MHz, CDCl3): δ 8.13 (1H, s), 8.11 (1H, s), 4.40 (2H, q, J = 7.06 Hz), 1.43 (3H, t, J = 7.0 Hz).

References:

More, Kunal N.;Jang, Hyo Weon;Hong, Victor S.;Lee, Jinho [Bioorganic and Medicinal Chemistry Letters,2014,vol. 24,# 11,p. 2424 - 2428] Location in patent:supporting information