2-Bromo-5-fluoropyridine → HCID 59457554, compound

Participants

Reaction Conditions

Reaction Steps

An oven dried resealable Schlenk tube was charged with 2-bromo-5-fluoropyridine (0.52 g, 2.9 mmol), hexamethylditin (0.97 g, 2.9 mmol) and toluene (15 mL). The Schlenk tube was subjected to three cycles of evacuation-backfilling with argon, and tetrakis(triphenylphosphine)palladium (0.162 g, 0.14 mmol) was added. After three new cycles of evacuation-backfilling with argon, the Schlenk tube was capped and placed in an oil bath at 80° C. After 5 hours, the mixture was cooled and N-[6-chloro-5-(3-fluoropyridin-4-yl)pyrazin-2-yl]cyclopropanecarboxamide (Preparation 10, 0.424 g, 1.45 mmol) and further tetrakis(triphenylphosphine)palladium (0.162 g, 0.14 mmol) were added. The mixture was heated to 110° C. and stirred overnight. The mixture was concentrated, ethyl acetate was added and the organic solution was washed with 4% aqueous sodium bicarbonate solution, brine, dried (MgSO4) and evaporated. The residue was purified by silica gel chromatography (CH2Cl2/MeOH 98:2). The appropriate fractions were concentrated to leave a solid which, upon washing with a mixture of hexane and ethyl acetate, gave the title compound (0.077 g, 15%) as an off-white solid.

Provenance & Evidence