1083168-94-8

The reaction was carried out with 5-bromo-2-methoxy-3-nitropyridine (5 g, 21.5 mmol) and pinacol ester of bis(boronic acid) (6.6 g, 25.8 mmol) in the presence of PdCl2(dppf)-CH2Cl2 (500 mg) and potassium acetate (6.3 g, 64.5 mmol) in anhydrous 1,4-dioxane (200 mL) at reflux for 2 hour. After completion of the reaction, the solvent was removed by distillation under reduced pressure. The crude product was purified by silica gel column chromatography with the eluent of petroleum ether:EtOAc = 10:1 to afford the target compound 2-methoxy-3-nitro-5-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-pyridine in 81% (5 g) yield. Mass spectral analysis showed m/z 281 (M + H)+.

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