Method for manufacturing hydrogen sulphate clopidogrel in crystalline form I

摘要

Described is a method for manufacturing hydrogen sulphate (alpha S) of the alpha-(2-chlorophenyl)-6,7dihydro-thieno[3,2- c]pyridine-5(4H)-acetic acid methyl ester (clopidogrel hydrogen sulphate) of formula (I) in crystalline form I, wherein the compound of formula is separated out of a solution of clopidogrel in the form of the free base or salt in a solvent selected from the series of primary, secondary or tertiary C1-C5 alcohols, their esters with C1-C4 carboxylic acids, or optionally of mixtures thereof, namely by cooling down, by precipitation with sulphuric acid, or by combination of both methods.