2-Fluoropyridine-3-boronic acid → HCID 58266636, compound

Participants

Reaction Conditions

Reaction Steps

A mixture of 6-bromo-4-iodo-pyridin-3-ylamine (10.0 g, 33.4 mmol), 2-fluoropyridine-3-boronic acid (5.2 g, 36.8 mmol) and 1,1′-[bis(diphenylphosphino)ferrocene]dichloropalladium(II) dichloromethane complex (2.73 g, 3.34 mmol) in acetonitrile (150 mL) and 1N aqueous potassium fluoride solution (150 mL) was degassed with nitrogen for 20 minutes. The reaction mixture was heated at 70° C. for 2.5 h, allowed to cool to ambient temperature and then partitioned between ethyl acetate (400 mL) and water (150 mL). The organic layer was separated, dried over anhydrous sodium sulfate, filtered and evaporated in vacuo. The resultant solid residue was triturated with dichloromethane: methanol (1:1, 100 mL), collected by filtration and washed with diethyl ether (50 mL) to furnish the title compound as a brown solid (3.5 g, 39%). The filtrate was evaporated and purified by passing the resultant residue through a pad of silica eluting with ethyl acetate:cyclohexane (1:1). Collection of the appropriate fractions and evaporation to dryness afforded a solid that was then triturated with diethyl ether to afford the title compound as a brown solid (3.7 g, 42%) (combined yield—7.22 g, 81%). 1H NMR (CDCl3, 300 MHz): 8.34 (ddd, J=4.9, 2.0, 1.2 Hz, 1H), 7.99 (s, 1H), 7.85 (ddd, J=9.4, 7.4, 2.0 Hz, 1H), 7.37 (ddd, J=7.4, 4.9, 2.0 Hz, 1H), 7.22 (s, 1H), 3.75 (s, 2H). LCMS (Method B): RT=2.78 min, M+H+=268/270.

Provenance & Evidence