This compound can be obtained in two related ways: 1) The reaction of codeinon (I) with ethyllithium and CuI in ether gives 4,5alpha-epoxy-8beta-ethyl-3-methoxy-17-methylmorphinan-6-one (II), which by treatment with cyanogen bromide and K2CO3 in CHCl3 is converted into 17-cyano-4,5alpha-epoxy-8beta-ethyl-3-methoxymorphinan-6-one (III). Elimination of the cyano group of (III) by treatment with refluxing aqueous 2N HCl yields 4,5alpha-epoxy-8beta-ethyl-3-methoxymorphinan-6-one (IV), which is finally alkylated with cyclopropylmethyl bromide (C) and NaHCO3 in DMF at 100 C. 2) The reaction of codeinon (I) with vinyl bromide (A), tert-butyllithium and CuI in ether gives 4,5alpha-epoxy-3-methoxy-17-methyl-8beta-vinylmorphinanone (V), which is reduced with H2, Pd/C in ethanol to yield (II).

This compound can be obtained in two related ways: 1) The reaction of codeinon (I) with ethyllithium and CuI in ether gives 4,5alpha-epoxy-8beta-ethyl-3-methoxy-17-methylmorphinan-6-one (II), which by treatment with cyanogen bromide and K2CO3 in CHCl3 is converted into 17-cyano-4,5alpha-epoxy-8beta-ethyl-3-methoxymorphinan-6-one (III). Elimination of the cyano group of (III) by treatment with refluxing aqueous 2N HCl yields 4,5alpha-epoxy-8beta-ethyl-3-methoxymorphinan-6-one (IV), which is finally alkylated with cyclopropylmethyl bromide (C) and NaHCO3 in DMF at 100 C. 2) The reaction of codeinon (I) with vinyl bromide (A), tert-butyllithium and CuI in ether gives 4,5alpha-epoxy-3-methoxy-17-methyl-8beta-vinylmorphinanone (V), which is reduced with H2, Pd/C in ethanol to yield (II).