4-Ethynyl-1-methyl-1H-pyrazole → 2-bromo-5-((1-methyl-1H-pyrazol-4-yl)ethynyl)pyridin-4-amine

Participants

Reaction Steps

4-Amino-2-bromo-5-iodopyridine (5) (2.58 g 8.63 mmole), copper(I) iodide (164 mg 0.86 mmole) and bis(triphenylphosphine)palladium dichloride (216 mg 0.432 mmole) were weighed into a 100 mL flask and DMF (25 mL) with triethylamine (22 mL) was added. The mixture was stirred at r.t. for 15 minutes under nitrogen. 4-Ethynyl-1-methyl-1H-pyrazole (20) (945 mg at 100%, 8.91 mmole) in DMF (10 mL) and triethylamine (5 mL) was added to the flask. The reaction was stirred at r.t. for 1.75 hrs. The reaction was diluted with ethyl acetate (450 mL) and the solution was washed with water (3×240 mL), brine (120 mL), dried and evaporated. The residue was flash chromatographed (silica/ethyl acetate) to give the title compound (2.11 g, 88%). 1H-NMR (CDCl3, 500 MHz): δ 3.94 (s, 3H), 4.80 (br s, 2H), 6.79 (s, 1H), 7.59 (s, 1H), 7.66 (s, 1H), 8.15 (s, 1H).

Provenance & Evidence