Hydrochloric Acid → Hydrocodone

Participants

Reaction Steps

A solution of 1 g of codeinone (prepared by the method of Gavard et al., Bull. Soc. Chim. Fr., 486 (1965)) in 25 ml of 95% ethanol was adjusted to about pH 1 with concentrated hydrochloric acid and was hydrogenated on a Paar apparatus at 50 psi using 200 mg of 10% Palladium on charcoal catalyst for about 1 hour. The catalyst was then removed by filtration and the filtrate was evaporated to give a solid residue. This residue was dissolved in water and the solution adjusted to about pH 11 with concentrated ammonium hydroxide solution. The basic solution was extracted with three portions of chloroform. The combined organic extracts were washed with water, dried over MgSO4 and evaporated to leave a solid residue. The residue was crystallized from absolute ethanol to give the product, which had a melting point of 191°-194° C., in 87% yield.

Provenance & Evidence