Acetic Acid → Oxymorphone

Participants

Reaction Conditions

Reaction Steps

HOAc (30 mL) and water (120 mL) were added to a 250 mL flask (pH=2.6, ˜150 mL). With the stirring mechanism on, oripavine (30.00 g, assayed to be 96% wt/wt, containing oripavine 97 mmol) was charged to the flask. Heat was released and the final solution reached 25° C. from 20° C., pH=3.66. The reaction mixture was cooled to 5˜10° C., and, CH3CO3H (23.4 g, containing 33% wt/wt peroxy acetic acid and 5.34% H2O2, 97 mmol peracetic acid) was added over 10 minutes. The reaction mixture was stirred for another 30 minutes after cooling bath was removed and the final temperature reached 15° C. The solution was heated to 55° C. over a 30 minute period and maintained at 55° C. for 1 hour. The reaction mixture was transferred to a pressure bearing flask (350 mL) for the reduction reaction. The flask for the oxidation was washed with the 2% HOAc (v/v; 2×7.5 mL). The washes were transferred to the reduction flask. 1.0 g of 10% Pd/C was added and the flask was pump/purged first with nitrogen and then with hydrogen each 4 times. The flask was cycled under vacuum and hydrogen 4 times. The reaction mixture was stirred under hydrogen (60 PSI) at 85° C. to 90° C. (90° C. oil bath) for 4.5 hours. The reaction mixture was cooled down to 35° C. and filtered. The recovered solid was washed with a solution of 2% HOAc/H2O (v/v, 3×15 mL). Yield of oxymorphone formed in the solution was calculated by HPLC analysis: 85%.

Provenance & Evidence