Dimethylformamide → HCID 59310819, compound

Participants

Reaction Steps

To a solution of bisphosphonate 23 (2.0 g, 5.95 mmol) in DMF (6 mL) was added NaH (60% dispersion in mineral oil, 254 mg, 6.35 mmol) portionwise. The solution was stirred for 45 min at room temperature and added to a solution of O-(diphenylphophinyl)hydroxylamine (1.35 g, 5.77 mmol) in THF (40 mL), cooled in a dry ice/acetone bath. The resulting mixture was stirred for 10 min at the same temperature then 18 h at room temperature. CH2Cl2 (40 mL) was added, the solids were removed by filtration and washed with several portions of CH2Cl2. The combined filtrates were concentrated in vacuo and purified by flash chromatography on silica gel using a gradient of 0-5% MeOH/EtOAc to provide aminobisphosphonate 24 as a clear yellow oil (1.24 g, 3.53 mmol, 59%). 1H NMR (400 MHz, CDCl3) δ 1.69 (bs, 2H), 3.52 (t, J=20.8 Hz, 1H), 4.64-4.67 (m, 8H), 5.24-5.27 (m, 4H), 5.36-5.42 (m, 4H), 5.92-6.02 (m, 4H).

Provenance & Evidence