Patent ID: 8178665

Claim:
A process for the preparation of ezetimibe of the Formula I comprising the following steps: a) converting 4-(4-fluorobenzoyl)-butyric acid of the Formula II into 4-[2-(4-fluorophenyl)-[1,3]dioxolane-2-yl]-butyric acid of the Formula IV through a non-isolated intermediate of Formula III, b) acylating a chiral compound of Formula V with the compound of Formula IV to obtain an acylated oxazolidinone derivative of the Formula VI, where the compound of Formula V is selected from the compounds of the Formulas Va, Vb, Vc, or Vd and wherein R1, R2 and R3 represent: in case of Va: R1=Ph, R2=R3=H, in case of Vb: R1=R2=R3=Ph, in case of Vc: R1=methyl, R2=Ph, R3=H and in case of Vd: R1=isopropyl, R2=R3=Ph, and where Ph represents phenyl group c) reacting the acylated oxazolidinone compound of Formula VI with a protected imine compound of Formula VII, and isolating the compound of Formula VIII, where R4 represents a silyl protecting group, cyclizing the compound of Formula VIII to obtain the protected azetidinone derivative of general Formula IX, d) hydrolizing the ketal group of the compound of Formula IX to obtain a compound of Formula X, e) reducing enantioselectively the compound of general Formula X to obtain the compound of Formula XI, f) removing the silyl protecting group of the compound of the general Formula XI to obtain the end-product ezetimibe of the Formula I