Potassium Carbonate → Diethyl 2-(3-ethynylphenylamino)ethylphosphonate

Participants

Reaction Steps

3-Ethynyl aniline (2.36 g, 22.1 mmol), diethyl 2-bromoethylphosphonate (5.41 g, 22.1 mmol) and potassium carbonate (3.1 gm, 22.1 mmol) were heated at 90° C. in anhydrous acetonitrile (40 mL) for 26 h. The solvent was removed under reduced pressure and the residue was partitioned between ethyl acetate and water. The organic layer was separated, washed with brine, dried over anhydrous sodium sulfate, filtered and concentrated under reduced pressure. The resulting residue was purified by flash column chromatography on silica gel, eluting with 1:1 ethyl acetate:hexanes followed by 97:3 methylene chloride:methanol to provide diethyl 2-(3-ethynylphenylamino)ethylphosphonate (450 mg) as a yellow oil. 1H NMR (CDCl3) δ 7.15 (t, 1H), 6.83 (d, 1H), 6.70 (br s, 1H), 6.60 (m, 1H), 4.10 (m, 4H), 3.41 (m, 2H), 3.00 (s, 1H), 2.10 (m, 2H), 1.35 ppm (m, 6H). MW=281 confirmed by LC-MS, tr=11.65 min (Method Y) MH+=282.

Provenance & Evidence