Iodopentafluoroethane → 1-(3-Bromo-4-fluoro-phenyl)-4,4,5,5,5-pentafluoro-pent-1-en-3-one

To a saturated solution of pentafluoroiodoethane (0.84 M, in diethyl ether) (37.7 mL, 32.9 mmol), was slowly added a solution of methyllithium/lithium bromide (1.5 M, in diethyl ether) (21.9 mL, 32.9 mmol) under nitrogen atmosphere at −78° C. The reaction mixture was stirred for 20 minutes and then a solution of 3-(3-bromo-4-fluoro-phenyl)-N-methoxy-N-methylacrylamide (3.2 g, 11.0 mmol, in tetrahydrofuran 10.0 mL) prepared in Step 3 was slowly added thereto at −78° C. The reaction mixture was stirred at room temperature, quenched with distilled water, acidified by a 10% potassium hydrogen sulfate solution (pH=5), and then extracted with ethyl acetate. The extract was washed with a saturated solution of sodium hydrogen carbonate, dried on anhydrous magnesium sulfate, and then concentrated under reduced pressure to give a yellow liquid residue. The resulting residue was purified by silica gel column chromatography (eluent: ethyl acetate/n-hexane=1/10) to give 2.5 g of the titled compound as a yellow liquid.

1. additionwas slowly added
2. customat −78° C
3. stirringThe reaction mixture was stirred at room temperature
4. customquenched with distilled water
5. extractionextracted with ethyl acetate
6. washThe extract was washed with a saturated solution of sodium hydrogen carbonate
7. dry with materialdried on anhydrous magnesium sulfate
8. concentrationconcentrated under reduced pressure
9. customto give a yellow liquid residue
10. customThe resulting residue was purified by silica gel column chromatography (eluent: ethyl acetate/n-hexane=1/10)

ORD record

ord-d976b836842144968c1732ee06833fc9

Source dataset

uspto-grants-2016_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09376420B2