Nitrogen → 3-cyclopropyl-1-((6-methylpyridin-2-yl)methyl)-4-nitro-1H-indazole

Participants

Reaction Conditions

Reaction Steps

3-Bromo-1-((6-methylpyridin-2-yl)methyl)-4-nitro-1H-indazole (10.0 g, 28.8 mmol), cyclopropylboronic acid (6.2 g, 72.0 mmol), palladium acetate (0.2 g, 0.9 mmol), triphenylphosphine (0.5 g, 1.7 mmol) and potassium carbonate (15.9 g, 115.2 mmol) were added to a mixture of H2O (50 mL) and toluene (50 mL) in a 250 mL round bottomed flask equipped with mechanical stirring, a thermal couple, a reflux condenser and a static pressure N2 line. The solution was degassed by sparging with N2 for 15 minutes and then heated with stirring under N2 at 90° C. for 18 hours. The solution was cooled to ambient temperature, treated with activated carbon, filtered through Celite®, and the filter cake was rinsed with toluene (100 mL). The filtrate was partitioned using a reparatory funnel and after extraction of the organic phase with H2O (2×50 mL) the organic layer was concentrated to dryness. The crude product was triturated with isopropyl alcohol (50 mL). The solids were collected by vacuum filtration, washed with heptane and dried under vacuum to afford 3-cyclopropyl-1-((6-methylpyridin-2-yl)methyl)-4-nitro-1H-indazole (6.9 g).

Provenance & Evidence