Methanol → (RS)-Clopidogrel

Participants

Reaction Conditions

Reaction Steps

1 g (0.00326 mol) (±)-(2-chlorophenyl)-(6,7-dihydro-4H-thieno[3,2-c]pyrid-5-yl)acetamide was dissolved in 20 mL methanol and refluxed at 85° C. During the reflux 10 mL polyphosphoric acid was added dropwise over a period of 1 hr and refluxing was continued for 6 hour. The excess of solvent was removed under reduced pressure. To the residue, 50 mL ethyl acetate was added at 0° C. and the reaction mixture was made basic with aq. NaHCO3, up to pH 9. Out of the two phases separated, the organic layer was isolated, dried over anhydrous Na2SO4 and concentrated. The residue obtained was purified by column chromatography using hexane:ethyl acetate (9:1) as eluent. The product obtained was stored under nitrogen atmosphere and kept in refrigerator before converting into salt. The yield of titled product was 310 mg (30%).

Provenance & Evidence