Acetic Anhydride → (S)-N-[3-(3-Fluoro-4-iodo-phenyl)-2-oxo-oxazolidin-5-ylmethyl]-acetamide

Participants

Reaction Conditions

Reaction Steps

A suspension of amine 107 (16.0 g, 47.6 mmol) in CH2Cl2 (150 mL) was treated with TEA (9.62 g, 13.2 mL, 95.2 mmol, 2.0 equiv) at 25° C., and the resulting reaction mixture was cooled to 0-5° C. before being treated with acetic anhydride (Ac2O, 7.29 g, 6.75 mL, 71.4 mmol, 1.5 equiv) and 4-N,N-dimethylaminopyridine (DMAP, 58 mg, 0.5 mmol, 0.01 equiv) at 0-5° C. under N2. The resulting reaction mixture was subsequently stirred at 0-5° C. for 2 h. When TLC and HPLC showed the reaction was complete, the reaction mixture was quenched with H2O (100 mL). The two layers were separated, and the aqueous layer was extracted with CH2Cl2 (2×50 mL). The combined organic extracts were washed with H2O (2×100 mL) and saturated aqueous NaCl (100 mL), dried over MgSO4, and concentrated in vacuo. The residue was further dried in vacuo to afford the desired (5S)—N-[3-(3-fluoro-4-iodo-phenyl)-2-oxo-oxazolidin-5-ylmethyl]-acetamide 108 (17.36 g, 96.5% yield) as a white powder. This product was directly used in subsequent reactions without further purification. 1H NMR (300 MHz, DMSO-d6) δ 1.63 (s, 3H, NHCOCH3), 3.25 (t, 2H, J=5.4 Hz), 3.56 (dd, 1H, J=6.4, 9.2 Hz), 3.95 (t, 1H, J=9.1 Hz), 4.58 (m, 1H), 5.16 (t, 1H, J=5.7 Hz, OH), 7.02 (dd, 1H, J=2.4, 8.2 Hz), 7.38 (dd, 1H, J=2.4, 10.8 Hz), 7.66 (t, 1H, J=7.5, 8.4 Hz), 8.08 (t, 1H, J=5.8 Hz, NHCOCH3). C12H12FIN2O3, LCMS (EI) m/e 379 (M++H).

Provenance & Evidence