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General procedure for the synthesis of 2-chloro-6-phenylpyrazine: to a solvent mixture of 2,6-dichloropyrazine (2.0 eq.) dissolved in a 3:1 ratio of aqueous DME with 2M sodium carbonate (0.125 M), phenylboronic acid (1.0 eq.) was added, followed by the addition of PdCl2(dppf)-DCM adduct (0.1 eq.). The reaction mixture was placed in a microwave reactor and heated at 120 °C for 15 min. After completion of the reaction, the crude product was diluted with ethyl acetate and washed with saturated aqueous NaHCO3 solution. After the aqueous phase was saturated with sodium chloride, the organic phase was dried with magnesium sulfate, filtered and concentrated. The crude product was purified by silica gel column chromatography with the eluent being heptane to a heptane solution containing 30% ethyl acetate, resulting in 2-chloro-6-phenylpyrazine in 75% yield.LC/MS analysis showed a m/z of 191.0 (MH+) and a retention time (Rt) of 1.00 min.

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