Phosphoric Acid → Nalbuphine

Participants

Reaction Steps

6-ketonalbuphine (40 g, 112.8 mmoles) was dissolved in a mixture of IPA (200 mls) and water (200 mls) containing orthophosphoric acid (1.56 mls). The pH of the reaction mixture was 6.49. The reaction mixture was hydrogenated at 40 psi hydrogen gas and 50° C. in the presence of 10% Platinum on carbon catalyst (2.4 g, 0.56 mmoles Pt). After 7 hours, the pH of the reaction mixture is adjusted with orthophosphoric acid (6.25 mls) and filtered. Ammonia solution (25 mls) was added to bring the pH to 8.5-9.0 and the precipitate filtered, washed with 50% aqueous IPA (60 mls), and dried to provide 39.33 g (97% theory) of Nalbuphine alkaloid of purity 95.6% by HPLC.

Provenance & Evidence