Iodine → 2-Fluoro-1-phenylethan-1-one

Temperature

140 °C

A mixture of (E)-3-[2-(Tributylstannyl)-ethenyl]-4-(4-fluoro-2-methylphenyl)-2-(1-methylethyl)-6-phenylpyridine (7.18 gm, 24.7 mmol), acetylene 1 (4.500 gm, 13.7 mmol) and AIBN (0.084 gm, 5.1 mmol) were heated at 140° C. for 1.5 hours. The solution was cooled to room temperature and diluted with ether (30 ml). Iodine (7.16 gm, 27.1 mmol) was added and an unexpectedly strong exothermic reaction occurred and approximately half the solution foamed out of the flask. The flask was recapped and allowed to stir 16 hours. The solution was then quenched with 10% Na2SO2O3 in saturated NaHCO3. The solution was diluted with ether, washed with 10% Na2SO2O3 in saturated NaHCO3 (twice) and brine, then dried over Na2SO4, filtered and concentrated to a yellow oil. The oil was purified by flash chromatography on Merck silica gel in 1% EtOAc in hexane. The desired fractions were combined and concentrated to afford a white solid, which was recrystallized from hexane to give product A as hard, off-white crystals (2.830 gm, 45%).

1. temperatureThe solution was cooled to room temperature
2. customan unexpectedly strong exothermic reaction
3. customThe solution was then quenched with 10% Na2SO2O3 in saturated NaHCO3
4. additionThe solution was diluted with ether
5. washwashed with 10% Na2SO2O3 in saturated NaHCO3 (twice) and brine
6. dry with materialdried over Na2SO4
7. filtrationfiltered
8. concentrationconcentrated to a yellow oil
9. customThe oil was purified by flash chromatography on Merck silica gel in 1% EtOAc in hexane
10. concentrationconcentrated
11. customto afford a white solid, which
12. customwas recrystallized from hexane

ORD record

ord-43f9050e20e34b328dc443c283150825

Source dataset

uspto-grants-1997_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05691322