| abstract |
The present invention provides a method for preparing losartan, which is prepared by reacting a cyano group-containing intermediate represented by formula (I) and an azide reagent in toluene in the presence of a catalyst, wherein, after the reaction is completed, it is removed by the following process Azide ion: adding water to divide the reaction system into three layers, separating the middle layer and adding n-butanol to it for dilution, adding triphenylphosphine to the resulting dilution to remove residual azide in the dilution ion. The preparation method provided by the invention does not need to use sodium nitrite, fundamentally eliminates the formation of genotoxic impurity nitrosamine, the obtained target product has good purity, high yield, simple and convenient preparation process, mild and easy-to-control operating conditions, and good safety , suitable for large-scale industrial production, |