Patent ID: 9562040
Date: 2017-02-07
CPC Classifications: A61P,C07D

Claim:
1. A process for preparing rivaroxaban or a pharmaceutically acceptable salt thereof, the process comprising (a) mixing a compound of formula (A) or a salt thereof, with an acylating agent to prepare a compound of formula (B) (b) crystallizing the compound of formula (B); (c) mixing the compound of formula (B) with a compound of formula (C) to prepare a compound of formula (D) or a salt thereof; where R A is halo or a protected amino group; and R B is halo, amino or a salt thereof, or a protected amino group; and (d) crystallizing the compound of formula (D); and, the process further comprising one or more steps selected from the group consisting of (e) converting the compound of formula (D) or a salt thereof, where R or a salt thereof; (f) converting the compound of formula (D) or a salt thereof, where R by contacting the compound of formula (D) with sodium azide; (g) reducing the compound of formula (F), or a salt thereof, into a compound of formula (E), by contacting the compound of formula (F) with a reducing agent; (h) mixing the compound of formula (E), or a salt thereof, with an acylating agent to prepare rivaroxaban, or a salt thereof; and (i) crystallizing rivaroxaban or a salt thereof from an organic acid; and combinations thereof, wherein step (c) includes a halide catalyst and the halide catalyst is magnesium bromide etherate, lithium bromide, or lithium bromide in combination with a phosphine oxide, such as tri-n-butylphosphine oxide.