NOVELTY - Improved process for the preparation of rivaroxaban (I) comprises: (a) reacting alkyl (4-(3-oxomorpholino)phenyl)carbamate (IV) with (S)-2-(oxiran-2-ylmethyl)isoindoline-1,3-dione (X) in presence of solvent to give (S)-2-((2-oxo-3-(4-(3-oxomorpholino)phenyl)oxazolidin-5-yl)methyl)isoindoline-1,3-dione (III); (b) deprotection of (III) with methyl amine or hydrazine hydrate to give (S)-4-(4-(5-(aminomethyl)-2-oxooxazolidin-3-yl)phenyl)morpholin-3-one (II); and (c) reacting (II) with 5-chlorothiophene-2-carboxylic acid (IX) in dichloromethane in presence of coupling reagents to give (I).    USE - The method is useful for preparing rivaroxaban (claimed), for treating thromboembolic diseases including heart attack, angina pectoris, and restenosis. No biological data given.    ADVANTAGE - The method: provides 99% pure rivaroxaban (claimed); is simple, utilizes cheap reagents and has mild reaction conditions; and is industrially feasible and environmentally friendly.    DETAILED DESCRIPTION - Improved process for the preparation of rivaroxaban of formula (I) comprises: (a) reacting alkyl (4-(3-oxomorpholino)phenyl)carbamate of formula (IV) with (S)-2-(oxiran-2-ylmethyl)isoindoline-1,3-dione of formula (X) in presence of solvent to give (S)-2-((2-oxo-3-(4-(3-oxomorpholino)phenyl)oxazolidin-5-yl)methyl)isoindoline-1,3-dione of formula (III); (b) deprotection of (III) with methyl amine or hydrazine hydrate to give (S)-4-(4-(5-(aminomethyl)-2-oxooxazolidin-3-yl)phenyl)morpholin-3-one of formula (II); and (c) reacting (II) with 5-chlorothiophene-2-carboxylic acid of formula (IX) in dichloromethane in presence of coupling reagents to give 5-chloro-N-(((5S)-2-oxo-3-(4-(3-oxo-4-morpholinyl)phenyl)-1,3-oxazolidin-5-yl)methyl)-2-thiphenecarboxamide (rivaroxaban) (I).    R = alkyl, aryl or aralkyl; and    X = H, nitro, halo (Cl, Br), amino, CN or amino protected.    INDEPENDENT CLAIMS are also included for:    (1) preparation of (III), comprising: reacting 4-(4-aminophenyl)morpholin-3-one in a solvent with compound (X) in presence of solvent to give (R)-2-(2-hydroxy-3-((4-(3-oxomorpholino)phenyl)amino)propyl)isoindoline-1,3-dione of formula (V), and carbonylation of (V) by using a carbonylating agent in an solvent to obtain (III); and    (2) (S)-2-((2-oxo-3-(4-(3-oxomorpholino)phenyl)oxazolidin-5-yl)methyl)isoindoline-1,3-dione (III).