Water → 3,5-Difluorobenzylphosphonic acid

Participants

Reaction Steps

Diethyl 3,5-difluorobenzylphosphonate (3.00 g, 11.4 mmol) was dissolved in dry dichloromethane (25 mL). Bromotrimethylsilane (4.9 mL, 37 mmol) was added via syringe. The reaction was capped with a greased glass stopper and allowed to stir for 6 hours. The volatiles were removed under reduced pressure to yield a yellow oil. This was dissolved in 8:1 methanol:water (25 mL) and allowed to stir overnight. After removing the solvents, recrystallization in acetonitrile yielded a white crystalline solid (1.98 g, 91% yield). 1H NMR (400.14 MHz, DMSO) δ 7.05 (dt, J=9.49, 2.09 Hz), 6.95 (d, J=8.54 Hz, 2H), 3.02 (d, J=21.57 Hz, 2H). 31P {1H} NMR (161.97 MHz, DMSO): δ 20.63. Analysis calculated (found) %: C 40.40(40.67), H 3.39 (3.39).

Provenance & Evidence