Patent ID: 8227609

Claim:
A process for producing noroxymorphone compounds from a crude product, said crude product having been obtained from a plant extract and consisting essentially of noroxymorphone compounds of formula (II), and comprising, as impurities, at least one of the α,β-unsaturated noroxymorphone compounds of the formulae (1a) and (1b), wherein said noroxymorphone compounds correspond to the following formula (II): in which R 1 is hydrogen or methyl as may be contained in the plant extract, or R 1 is a detachable leaving group as subsequently produced synthetically from a natural source, characterized in that: (a) said crude product is treated in a reaction which converts the hydroxyl groups present in the mixture to leaving groups of the formula —OR 2 in which R 2 is the introduced radical of a leaving group, (b) these leaving groups are detached, (c) the resulting mixture is subjected to a selective hydrogenation by which a saturated bond is formed in the α,β-position of the α,β-unsaturated noroxymorphone compounds and any remaining leaving groups are each detached and then, (d) the pure noroxymorphone compound is isolated.