Process for the Preparation of Valsartan and its Intermediates

摘要

The present invention concerns a process for preparing valsartan of Formula I:
comprising purifying intermediate benzyl valsartan of Formula IV by crystallizing said benzyl valsartan of lower purity from a first solvent which is a ternary mixture comprising a hydrophilic solvent, a non-polar protic solvent and water; recovering benzyl valsartan from said ternary mixture followed by crystallizing benzyl valsartan from a second solvent comprising a non-polar aprotic solvent or polar aprotic solvent or their mixture; and recovering benzyl valsartan substantially free of organotin impurity; and converting said benzyl valsartan of into valsartan