To 3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyridin-2-amine(7.37 g, 33.5 mmol) in 500 mL round bottom flask were added methyl 4-bromo-2-methylbenzoate (6.390 g, 27.9 mmol), PdCl2(dppf)-DCM (2.041 g, 2.79 mmol), DME (209 mL) and 2 M Na2CO3 solution (69.7 mL). The reaction mixture was bubbled through N2 for 20 min and heated in an oil bath at 108° C. for 1.5 h. The reaction mixture was diluted with EtOAc, washed with water three times, dried over Na2SO4, filtered and concentrated. The crude product was purified by flash chromatography eluting with 0-100% of EtOAc (containing 10% of MeOH)/heptane to provide crude product around 8 g which contained fair amount of B2(PIN)2 from previous experiment. Ether was added to dissolve the crude mixture, and then heptane was added to crush out the desired product. Solid was filtered out to provide 4.2 g of desired product with high purity in 62.1% yield. LCMS (m/z): 243.5 (MH+), 0.56 min.
