Hydrazine hydrate (1:1) → (5S)-5-(aminomethyl)-3-(3-fluorophenyl)-1,3-oxazolidin-2-one

Participants

Reaction Steps

A solution of phthalimide 98 (3.0 g, 8.82 mmol) in EtOH (30 mL) was treated with hydrazine monohydrate (2.20 g, 2.2 mL, 44.12 mmol, 5.0 equiv) at 25° C., and the resulting reaction mixture was warmed to reflux for 2 h. White precipitates formed as the reaction mixture was refluxed. When TLC and HPLC showed the reaction was complete, the reaction mixture was cooled to room temperature before being quenched with H2O (20 mL). The aqueous solution was then extracted with CH2Cl2 (3×40 mL), and the combined organic extracts were washed with H2O (2×20 mL) and saturated aqueous NaCl (20 mL), dried over MgSO4, and concentrated in vacuo. The residue was further dried in vacuo to afford the desired (5S)-5-aminomethyl-3-(3-fluoro-phenyl)-oxazolidin-2-one (amine 99, 1.79 g, 96.6% yield) as a white powder. This product was directly used in the subsequent reactions without further purification. C10H11FN2O2, LCMS (EI) m/e 211 (M++H).

Provenance & Evidence