2-Cyclohexen-1-one → 3-(2-Fluoropyridin-3-yl)cyclohex-2-enone

Participants

Reaction Steps

A solution of 3-bromo-2-fluoropyridine (11 g, 62.5 mmol), 2-cyclohexen-1-one (24.03 g, 250 mmol), N,N-dicyclohexylmethylamine (30.5 g, 156 mmol) and bis(tri-t-butylphosphine)palladium (o) (0.958 g, 1.875 mmol) in dioxane (80 mL) was heated to 105° C. for 6 h. The mixture was cooled to RT and the dioxane was evaporated under reduced pressure. Water (200 ml) was added and the mixture layer was extracted with EtOAc (2×200 ml). The combined organic layers were washed with brine and dried over sodium sulfate. Filtration and concentration under reduced pressure, followed by flash chromatography on silica gel (20% to 50% EtOAc in hexanes) afforded 3-(2-fluoropyridin-3-yl)cyclohex-2-enone as colorless crystals. MS (ESI, pos. ion) m/z: 191.9 (M+1).

Provenance & Evidence