US Patent 7429661 Intermediates for linezolid and related compounds

The present invention provides a novel process for preparation of 5 aminomethyl substituted oxazolidinones, key intermediates for oxazolidinone antibacterials including linezolid. Thus, the key intermediate of linezolid is prepared by a) reacting N-[3-Chloro-2-(R)-hydroxypropyl]-3-fluoro-4-morpholinyl aniline with potassium phthalimide; b) subjecting N-[3-pthalimido-2-(R)-hydroxypropyl]-3-fluoro-4-(morpholinyl) aniline produced in the above step to carbonylation; and c) reacting (S)-N-[[3-[3-Fluoro-4-[4-morpholinyl]phenyl]-2-oxo-5-oxazolidiriyl]methyl]phthalimide produced in the above step with hydrazine hydrate to produce (S)-N-[[3-[3-Fluoro-4-[4-morpholinyl]phenyl]-2-oxo-5-oxazolidinyl]methyl]amine.