合成路线1

The title product can be obtained in several steps: 1) (+)-2-(2-Chlorophenyl)glycine methyl ester [(+)-IV] is prepared as follows: a) Racemic 2-(2-chlorophenyl)glycine (I) is methylated with methanol - HCl to the methyl ester (II), which is resolved with (+)-tartaric acid to the active ester [(+)-IV]. b) Racemic (I) is resolved with (+)-10-camphorsulfonic acid to (+)-2-(2-chlorophenyl)glycine [(+)-III], which is then esterified as before to [(+)-IV]. 2) (+)-2-(2-Chlorophenyl)-N-[2-(2-thienyl)ethyl]glycine methyl ester [(+)-VII] is prepared as follows: a) Alkylation of [(+)-IV] with 2-[2-(phenylsulfonyloxy)ethyl]thiophene (V) or with 2-(2-bromoethyl)thiophene (VI). b) Optical resolution of racemic alkylated glycine ester (VIII) with (+)-10-camphorsulfonic acid. 3) Finally, (+)-clopidogrel is prepared as follows: a) Cyclization of active [(+)-VII] with formaldehyde - formic acid and aqueous HCl. b) Cyclization of racemic (VIII) as before, yielding racemic clopidogrel (PCR-4099), followed by optical resolution with (+)-10-camphorsulfonic acid.