Iodopentafluoroethane → 1-(5-Bromo-pyridin-3-yl)-4,4,5,5,5-pentafluoro-pent-1-en-3-one

To a saturated solution of pentafluoroiodoethane (0.84 M, in diethyl ether) (108.0 mL, 91.0 mmol), was slowly added a solution of methyllithium/lithium bromide (1.5 M, in diethyl ether) (61.0 mL, 91.0 mmol) under nitrogen atmosphere at −78° C. The reaction mixture was stirred for 20 minutes and then a solution of 3-(5-bromo-pyridin-3-yl)-N-methoxy-N-methyl-acrylamide (8.2 g, 30.3 mmol, in diethyl ether/tetrahydrofuran 50.0 mL/150.0 mL) prepared in Step 2 was slowly added thereto at −78° C. The reaction mixture was stirred at room temperature for 2 hours, 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=1/5) to give 2.9 g of the titled compound as a yellow solid.

1. additionwas slowly added
2. customat −78° C
3. stirringThe reaction mixture was stirred at room temperature for 2 hours
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=1/5)

ORD record

ord-1f518ac270b948ea8139add0b39efaaf

Source dataset

uspto-grants-2016_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09376420B2