ethyl 2-(4,4-difluorocyclohexylidene)acetate

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution of 4,4-difluorocyclohexan-1-one (1.0 g, 7.46 mmol, 1.00 equiv) and (carbethoxymethylene)triphenylphosphorane (3.9 g, 24.05 mmol, 1.50 equiv) in THF (20 mL) was stirred under argon overnight at 65° C. After cooling to ambient temperature, the mixture was concentrated under reduced pressure and the crude residue was purified using flash column chromatography (silica gel, EtOAc/petroleum ether (1:10)) to yield 1.5 g (97%) of a colorless oil. 1H-NMR (400 MHz, CDCl3): δ ppm 5.75 (s, 1H), 4.18 (m, 2H), 3.06 (t, J=6.8 Hz, 2H), 2.34 (t, J=6.8 Hz, 2H), 2.11-1.99 (m, 4H), 1.33-1.26 (m, 3H). the mixture was concentrated under reduced pressure the crude residue was purified