Potassium Phosphate, Tribasic → 5-(2-bromo-5-(trifluoromethyl)phenyl)-1-methyl-1H-pyrazole

関与物質

反応条件

反応手順

A round-bottom flask was charged with 1-bromo-2-iodo-4-(trifluoromethyl)benzene (5.00 g, 14.25 mmol), 1-methyl-1h-pyrazole-5-boronic acid pinacol ester (3.41 g, 16.39 mmol), potassium phosphate (6.05 g, 28.5 mmol) and PdCl2(dppf)-CH2Cl2 (1.164 g, 1.425 mmol). The flask was flushed with Ar, and DMF (47.5 ml) was then added. The flask was sealed, heated to 60° C. for 12 h, then stirred at room temperature for 48 h. The mixture was diluted with water and extracted with EtOAc (3×). The combined organics were washed with brine, dried, and concentrated in vacuo. The crude product was purified by chromatography on silica gel (0 to 100% EtOAc/Heptane) to yield 5-(2-bromo-5-(trifluoromethyl)phenyl)-1-methyl-1H-pyrazole (2.956 g, 9.69 mmol, 68.0% yield) as a brown solid. 1H NMR (400 MHz, DMSO-d6) δ=8.06 (td, J=0.7, 8.1 Hz, 1 H), 7.86-7.73 (m, 2 H), 7.53 (d, J=2.0 Hz, 1 H), 6.41 (d, J=2.0 Hz, 1 H), 3.64 (s, 3 H). m/z (ESI) 305.0 (M+H)+.

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