Losartan → Losartan potassium salt

Participants

Reaction Steps

A solution of potassium hydroxide (9.4 g) and isopropyl alcohol (200 mL) was slowly added to a suspension of losartan (60 g) in isopropyl alcohol (280mL). The reaction mixture was stirred for about 2 hours at room temperature. The mixture was filtered, heated to reflux, concentrated to about a 180 mL volume and stirred for about 12 hours at room temperature. The precipitate was filtered, washed with isopropyl alcohol, and dried under reduced pressure for about 2 hours at about 50° C. to give losartan potassium (52.2 g, 85% yield) as a white powder. Purity was determined to be 99.74% by HPLC. Losartan potassium (1.0 g) was triturated with ethyl acetate (10 mL) and recovered from the triturate in a purity of 99.775% by HPLC.

Provenance & Evidence