Potassium Hydroxide → Treprostinil

Participants

Reaction Steps

2-((1R,2R,3aS,9aS)-2,3,3a,4,9,9a-hexahydro-2-hydroxy-1-((S,E)-3-hydroxyoct-1-enyl)-1H-cyclopenta[b]naphthalen-5-yloxy)acetic acid (2.5 g, 0.008 mol) in dry methanol (25 ml) was treated with potassium hydroxide (0.5 g, 0.008 mol), then with 5% Pd/C (0.5 g, 20% wt) under hydrogen overnight at room temperature. Then, the reaction mixture was filtered with celite pad. The solvent was evaporated off under vacuum. The residues was diluted with 50 nm ethyl, acetate and 50 ml saturated sodium bicarbonate aqueous. The mixture was phase separated and the organic layers was extracted with 50 ml saturated sodium bicarbonate aqueous. The aqueous layers were combined and then 3N HCl was added slowly until pH=˜2. The aqueous layer was extracted with 100 ml ethyl acetate. The organic layers were combined and dried over anhydrous magnesium sulfate. The solid was filtered off. The solvent was evaporated off under vacuum. The crude product was purified by crystallization. The titled compound was obtained in a crystalline form. Yield: 88%

Provenance & Evidence