Triethylamine → tert-Butyl 4-(6-bromo-1-(methylsulfonyl)-1H-pyrrolo[3,2-c]pyridin-2-yl)-1H-pyrazole-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

To a mixture of N-(2-bromo-5-iodopyridin-4-yl)methanesulfonamide (8) (419 mg, 1.11 mmol) and tert-butyl 4-ethynyl-1H-pyrazole-1-carboxylate (4) (277 mg, 1.44 mmol, 1.3 equiv) was added copper(I) iodide (7.4 mg 0.039 mmole) and DMF (4 mL), followed by triethylamine (0.69 mL, 497 mg, 4.92 mmol). The reaction was flushed twice with nitrogen. Bis(triphenylphosphine)palladium chloride (27 mg, 0.038 mmole) was added and the reaction flushed twice more with nitrogen, it was heated at 60° C. for 70 minutes. The reaction was added to water (40 mL) and extracted with ethyl acetate (3×20 mL). The combined extracts were washed with water (3×20 mL) and with brine, dried and evaporated. The residue was purified on four 2 mm 20×20 cm silica prep tlc plates, eluted with 3:1 ethyl acetate:cyclohexane. The product band was recovered with acetone giving the title compound (251 mg, 51%). 1H-NMR (CDCl3, 500 MHz): δ 1.73 (s, 9H), 3.02 (s, 3H), 6.81 (s, 1H), 7.97 (s, 1H), 8.26 (s, 1H), 8.43 (s, 1H), 8.69 (s, 1H).

Provenance & Evidence