Ethyl formate → Diethyl [difluoro(4-formylphenyl)methyl]phosphonate

Temperature

-78 °C

To a solution of [Difluoro-(4-iodo-phenyl)-methyl]-phosphonic acid diethyl ester (1.6 g, 4.1 mmol) in anhydrous ether (40 mL) at -78° C. was added dropwise n-butyl lithium (2.5 M in hexanes, 2.5 mL, 6.1 mmol). The brown solution was stirred at -78° C. for 2 minutes. Ethyl formate (0.66 mL, 8.2 mmol) was then added, and the reaction was stirred for 10 minutes at -78° C. The mixture was then quenched with saturated ammonium chloride (10 mL) and warmed to room temperature. The reaction was then diluted with ether. The organic layers were washed with saturated sodium chloride (20 mL), dried over magnesium sulfate, filtered, and concentrated under reduced pressure to yield a yellow oil. Chromatography of the residue [3:7, ethyl acetate:hexanes] gradient to (1:1)] afforded the aldehyde (268 mg, 22%) as a clear oil. 1H NMR (400 MHz, DMSO): δ 10.28 (s, 1H), 8.25 (d, 2H), 7.97 (d, 2H), 4.42 (m, 4H), 1.40 (t, 6H).

1. stirringthe reaction was stirred for 10 minutes at -78° C
2. customThe mixture was then quenched with saturated ammonium chloride (10 mL)
3. temperaturewarmed to room temperature
4. additionThe reaction was then diluted with ether
5. washThe organic layers were washed with saturated sodium chloride (20 mL)
6. dry with materialdried over magnesium sulfate
7. filtrationfiltered
8. concentrationconcentrated under reduced pressure
9. customto yield a yellow oil

ORD record

ord-f4dfd7e963844b378aa4b19f7cbf3d57

Source dataset

uspto-grants-1999_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05922697