Potassium Carbonate → 3-tert-butyl-4-methyl-1-(2-methylphenyl)-1H-pyrazol-5-amine

Participants

Reaction Conditions

Reaction Steps

To a solution of 4-bromo-3-tert-butyl-1-(2-methylphenyl)-1H-pyrazol-5-amine (Intermediate J, 800 mg, 2.60 mmol) in DMF (5 mL) was added trimethylboroxine (0.73 mL, 5.19 mmol), [1,1′-bis(diphenylphosphino)-butane]palladium (II) dichloride (157 mg, 0.26 mmol), and potassium carbonate (1.08 g, 7.79 mmol). The reaction mixture was stirred for 18 h at 155° C. After cooling, the reaction mixture was diluted with water (100 mL) and extracted with EtOAc (3×25 mL). The combined organic layers were washed with brine, dried (Na2SO4), filtered, and concentrated under reduced pressure. The residue was purified by silica gel flash chromatography using hexane/EtOAc (1:9, v/v) to afford the product (243 mg, 38%) as a white solid: 1H NMR (300 MHz, DMSO-d6) δ 1.24 (s, 9H), 1.97 (s, 3H), 2.03 (s, 3H), 4.48 (s, 2H) 7.14-7.32 (m, 4H). ES-MS m/z 244.2 (MH+); HPLC RT (min) 1.17.

Provenance & Evidence