Patent ID: 7816355

Claim:
A process for the preparation of at least one of S-Rivaroxaban and R-Rivaroxaban comprising reacting, in the presence of a first base, a compound of Formula 9: with a compound of Formula 8: wherein R 4 is selected from the group consisting of: wherein G is OR 1 , NR 2 R 3 , or CX 3 ; R 1 is alkyl, substituted alkyl, aryl, substituted aryl, arylalkyl, or substituted aryl alkyl; R 2 and R 3 are either (a) two independent groups or (b) together form a single ring group with the N to which they are bonded; R 2 and R 3 , when independent groups, are independently selected from the group consisting of: H, alkyl, substituted alkyl, aryl, substituted aryl, arylalkyl and substituted arylalkyl, R 2 and R 3 , when together form a single ring group with the N to which they are bonded, are a heteroaryl ring; X is halogen; and L 2 is a halogen or sulfonyloxy group.